The veterinary healthcare team plays an important role in ensuring puppies mature into well-behaved dogs. With an understanding of normal development, clinicians can be a primary source for providing appropriate guidance to owners during the 4 developmental stages of dogs to help prevent undesirable behaviors.

Behavioral development is integrated with physical maturation and development of the nervous system. Puppy development is divided into 4 stages: neonatal, transitional, socialization, and juvenile.⁴ However, these stages are not rigidly fixed; different breeds may develop at different rates,⁵ and environmental factors can affect genetic expression. Prenatal conditions (eg, diet and health of the dam) can influence puppy development. Research in other species has shown that the offspring of mothers subjected to stressful handling are more sensitive to stressors.^6,7 However, these 4 periods continue to be useful reference points for discussions of puppy development.

The neonatal stage ranges from birth to ≈2 weeks of age; eyes are not yet open, and ear canals are closed, so puppies experience the world mainly through touch and olfaction.^8,9

Despite an immature nervous system, neonates respond to their environment. In a study, puppies that received more maternal care during this period scored higher for social and physical engagement as adults than those raised by less attentive mothers.¹⁰ In another study, puppies gently handled by humans starting at 3 days of age were calmer and more confident at 8 weeks of age as compared with controls.¹¹ Foster families and breeders should be advised to introduce soft handling of puppies as early as possible.

The transitional stage lasts ≈7 days (range, ≈14-21 days of age).^8,12 Eyes and ears begin to function, and muscle coordination improves. Social communication (eg, growling) and interactions (eg, play) are first observed during this period. Puppies become more aware of their environment and are able to eliminate without maternal stimulation. Because puppies can move further from the nesting area, this is an ideal time to introduce an appropriate elimination substrate.

Socialization refers to the process of developing appropriate social behaviors toward conspecifics. In practice, “socialization” is applied more broadly to include the development of social behaviors toward any species and the process of adjustment to relevant environmental stimuli.

A sensitive period is considered a phase in which external stimuli are particularly likely to have a long-term effect on development. Preferences are acquired more readily during this period.¹³ The sensitive period of socialization in puppies begins at 3 weeks of age and lasts until 12 to 14 weeks of age.^8,9,12 Puppies that have not been socialized during this time have a tendency to react fearfully to novel humans or situations.⁴ 

Controlled exposure to humans during the socialization period is crucial. Even small amounts of handling can result in beneficial effects. In one study, puppies not handled until 7 weeks of age were more hesitant to approach humans than were puppies handled at 3 to 5 weeks of age.¹⁴ Puppies not handled until 14 weeks of age remained persistently fearful and resistant to handling.¹⁴

Negative experiences during the sensitive period can also have a profound impact on behavioral development. Abrupt weaning, particularly when paired with sudden separation from littermates, may have long-term consequences on behavior. Puppies removed from the dam and litter prior to 6 weeks of age have been shown to be more fearful and have exhibited more undesirable behaviors as adults as compared with puppies that remain with the litter through 8 weeks of age.^15,16

The juvenile stage represents the time from the end of the socialization period to sexual maturity. Sexual behavior is generally observed at ≈6 months of age, although it may be delayed in large and giant breeds.⁹ 

Dogs remain behaviorally immature even after they have reached sexual maturity. Large-breed dogs may not mature socially until they are 18 months of age or older.⁸ Because behavior problems are frequently reported during this period, adolescent behavioral well-care visits should be encouraged.

It is never too early to start socializing a puppy, and, as long as the puppy remains calm and not fearful, it is never too late to begin. The owner’s goals should be considered when customizing a socialization program, and stimuli relevant to their puppy’s future should be introduced.

Healthy puppies of any age can begin to visit new places at least twice a week. Owners should take care to avoid locations frequented by dogs of unknown health and vaccination status. The puppy should be allowed to explore at its own comfortable pace. Bringing treats and toys can make the experience more pleasant, but if the puppy becomes too frightened to play or take a snack, the session should be ended.

The puppy should be introduced to a variety of humans, beginning with quiet adults. Children that are old enough to be quiet and gentle with dogs should then be introduced. Puppies can be carefully socialized with healthy puppies and adult dogs that are known to be gentle with puppies.

For some puppies, even mild stimuli may seem overwhelming. The socialization plan for these puppies should be modified accordingly. If fear is profound or persistent, a more in-depth behavioral treatment plan should be discussed with the owner, and referral to a boarded veterinary behaviorist is never premature. Repeated exposure in the face of profound fear can lead to sensitization and may not be reversible.

Puppy socialization classes are an opportunity for puppies to learn how to behave calmly around humans and dogs. Puppies that attend socialization classes are less likely to be rehomed than puppies that do not attend similar classes.¹⁷

It is important to be aware that puppies do not complete vaccinations until they are 12 to 16 weeks of age. However, a survey-based study found that the risk for a puppy contracting canine parvovirus at a socialization class is low,¹⁸ and inadequate behavioral inoculation may result in rehoming. Evaluating enrollment requirements for local puppy classes may be beneficial in minimizing this risk. An instructor who requires initial vaccinations and veterinary health certificates is ideal. The classes should be well-run so that puppies are not overwhelmed or frightened.

A brief behavioral history should be obtained for all puppies. Owners should be asked about any concerns they are experiencing with their puppy. Handouts should be provided to pet owners to help them manage normal but undesirable behaviors (eg, mouthing, house soiling, destructive behavior, barking). Such behaviors typically do not resolve on their own and may often escalate if owners attempt inappropriate techniques based on their own research.

Puppies are usually presented for initial examinations while in their sensitive period for socialization. Positive and negative experiences have a profound impact on future behavior. Puppies that experience positive veterinary visits are more likely to become cooperative patients that can receive good healthcare for years to come.

Both physical and behavioral observations should be included in the patient’s medical record. Normal puppies will explore the room and relax during the physical examination,¹⁹ whereas fearful puppies need special attention to assure a positive experience; some may require behavioral therapy.

Clinicians should follow up with owners to ensure they remain committed to providing excellent socialization opportunities for their puppy. As puppies mature, new behavioral concerns often develop. A plan should be developed to provide behavioral check-ups every 4 to 6 months until social maturity is reached.

Clinicians are in a unique position to positively affect the social development of puppies. Early, accurate behavioral advice increases the strength of the bond between the owner and the puppy, improves the puppy’s ability to accept excellent medical care, and helps create a strong clinician–owner–patient relationship.

Hallmark clinical features of asthma include bronchoconstriction, airway edema, airway eosinophilia, and excessive mucus production. The combination of these features can result in cough, tachypnea, and/or expiratory dyspnea.^1,3 Compounding airway edema, smooth muscle bronchoconstriction, and mucus hypersecretion can result in airflow limitation, which can be at least partially reversible with bronchodilator therapy. If left untreated, chronic airway inflammation can result in irreversible airway remodeling. 

Clinical signs associated with feline asthma include cough, tachypnea, open-mouth breathing, and/or respiratory distress, typically characterized by a prolonged expiratory phase of respiration and abdominal push. Some patients may have only one of these clinical signs, whereas others may have both a chronic cough and intermittent exacerbations resulting in respiratory distress with expiratory effort.³ Accordingly, clinical signs can be episodic and vary in severity, from a mild, intermittent cough to life-threatening dyspnea (ie, status asthmaticus). Pet owners may struggle to identify a true cough and may be confused with “vomiting hairballs” without production of a hairball.

Definitive diagnosis of feline asthma can be challenging due to clinical features that overlap with various other cardiopulmonary conditions, including chronic bronchitis, heartworm-associated respiratory disease, and pulmonary parasitic disease. Diagnosis can be facilitated through a combination of consistent historical information, clinical signs (ie, cough and/or respiratory distress), physical examination, laboratory data (eg, CBC, serum chemistry profile, fecal flotation and analysis, urinalysis, heartworm antigen and antibody testing), imaging (eg, thoracic radiography, thoracic ultrasonography, CT, bronchoscopy, echocardiography), airway sampling, and additional diagnostic testing (eg, airway cytology) to rule out other causes of eosinophilic airway inflammation.

Physical examination may be normal or may reveal tachypnea, inducible cough on tracheal palpation, and/or abnormalities on thoracic auscultation (eg, increased bronchovesicular sounds, expiratory wheezes). Classic radiographic findings include a diffuse bronchial or bronchointerstitial pattern, hyperinflation due to air trapping, and/or collapse of the right middle lung lobe due to mucus plug obstruction (Figure 1).^3,4 Because ≈20% of asthmatic cats have normal thoracic radiographs, asthma should remain on the differential list for any cat with respiratory distress and normal thoracic radiographs.⁵ In addition, a bronchial or bronchointerstitial pattern is also the predominant pulmonary pattern seen in cats with chronic bronchitis and/or heartworm-associated respiratory disease, making it challenging to differentiate these conditions from asthma via only physical examination and radiography.

Bronchoscopy may be used in asthmatic cats to evaluate airway structure and collect bronchoalveolar lavage fluid (BALF) for cytology, culture and susceptibility testing, and Mycoplasma spp PCR testing. Alternatively, blind bronchoalveolar lavage may also be performed in cats that show diffuse radiographic changes. Clinicians should be cautious when interpreting BALF culture and Mycoplasma spp PCR results in combination with BALF cytology results, as airways (especially the trachea) are not sterile and the presence of bacteria or Mycoplasma spp does not equate to active infection.⁶

Bronchoscopy findings are often nonspecific in asthmatic patients and may include excessive mucus accumulation, airway hyperemia, and/or epithelial irregularities.¹ Eosinophilic airway inflammation is characteristic of but not specific to asthma (Figure 2), as parasitic disease commonly results in airway eosinophilia. Historically, eosinophilic airway inflammation has been defined as >17% eosinophils present in BALF; however, recent evidence suggests that >5% eosinophils is considered abnormal in feline BALF.^7,8 Clinicians should evaluate BALF eosinophil percentage in light of clinical signs and concurrent conditions associated with eosinophilia (eg, allergic skin disease). Most asthmatic cats typically have significant BALF eosinophilia; some can have lower eosinophil and higher neutrophil numbers, particularly in chronic asthma cases. A heartworm antigen and antibody test, fecal flotation, and Baermann test should be performed in all cases. In addition, the author commonly institutes empiric antiparasitic treatment, even if results are negative.

Management of feline asthma consists of both acute and chronic treatment strategies. Clinicians and owners should understand that asthma is not a condition that can be cured; lifelong environmental and medical management are necessary.

Cats presented in status asthmaticus require acute management consisting of supplemental oxygen, stress reduction and minimal handling, and bronchodilator therapy (eg, inhaled albuterol [via metered dose inhaler], injectable terbutaline). In the author’s clinical experience, injectable terbutaline is preferred over inhaled albuterol in the emergency setting, as cats in respiratory distress typically may not inspire deeply enough to appropriately deliver inhaled medication to the lower airways. Identifying an expiratory respiratory pattern can be suggestive of bronchoconstriction and may lead the clinician to implement early intervention with bronchodilator therapy. Expiratory respiratory patterns are characterized by an abdominal push during exhalation. If an obvious expiratory pattern is not identified, evaluation for other causes of respiratory distress (eg, pleural effusion, congestive heart failure) should be performed prior to empiric treatment with a bronchodilator. Clinicians should evaluate patients for a heart murmur or gallop rhythm and perform cage-side thoracic ultrasonography to assess for pleural effusion and/or pulmonary edema (eg, presence of B lines). If other causes of respiratory distress are not evident on initial evaluation, intervention with a bronchodilator for possible asthma may be warranted.

Management of chronic feline asthma is aimed at reducing airway inflammation and preventing or reducing airflow-limiting bronchoconstriction.¹ Reduced inflammation is best achieved by minimizing exposure to aeroallergens and environmental irritants (eg, aerosols, dust) and administration of oral glucocorticoids (eg, prednisolone). Minimizing environmental allergens is best achieved by reducing exposure to known allergens (eg, eliminating outdoor access), cleaning bedding and other surfaces in the household frequented by the cat, and using an air filter to improve air quality. Oral glucocorticoid (prednisolone) therapy should be initiated at a dose of 1-2 mg/kg/day. The dose may be tapered by 25% to 50% every 2 to 4 weeks depending on clinical response. The goal is to taper steroids to the lowest effective dose.

Some cats can be transitioned to receiving only inhaled steroid therapy (eg, fluticasone) to minimize the systemic adverse effects of oral glucocorticoids and maintained on inhaled glucocorticoids alone for long-term management.⁹ It is important to overlap the inhaled steroid with oral glucocorticoid therapy, as it is believed that inhaled glucocorticoids require ≈2 weeks to achieve full clinical effect. Although the author frequently initiates inhaled fluticasone at a dose of 110 μg every 12 hours, a study evaluating inhaled fluticasone in cats with experimentally induced asthma found that airway eosinophilia was controlled with a variety of doses, including 44 μg, 110 μg, and 220 μg, administered every 12 hours.⁹ The efficacy of lower-dose fluticasone has not been evaluated in cats with naturally occurring asthma. In cats with concurrent conditions in which systemic glucocorticoids are contraindicated (eg, congestive heart failure, diabetes mellitus), inhaled glucocorticoid therapy and/or oral cyclosporine may be considered.^9,10

Chronic bronchodilator therapy is not necessary in all cats with asthma and is only recommended in patients that have signs associated with bronchoconstriction (eg, respiratory distress, episodic tachypnea). Inhaled racemic albuterol should not be used for chronic management of bronchoconstriction due to the proinflammatory effects of the S-enantiomer; however, racemic albuterol can be used at home by owners for rescue as needed.¹¹ Oral terbutaline or theophylline may also be used for chronic bronchodilator therapy. Although many patients may need bronchodilator therapy initially, once airway inflammation is controlled with glucocorticoid therapy, many can be weaned off bronchodilators long-term and managed as needed. In addition, feline asthma should never be managed with bronchodilator therapy alone, as bronchodilators will not address airway inflammation, which is an integral component of controlling asthma.

Various other therapeutic drugs (ie, cyproheptadine, cetirizine, nebulized lidocaine, maropitant) have been investigated for management of experimentally induced asthma in cats^12-14; although some show promise in reducing airflow limitation, none have been shown to be effective as monotherapy for management of feline asthma. As a result, these other therapeutics can be considered as adjunctive treatments along with glucocorticoids. Immunotherapy and mesenchymal stem cell therapy have shown promise as future novel therapeutics and warrant further investigation both in cats that have experimental and naturally occurring asthma.^15,16

Prognosis for feline asthma is typically good with prompt diagnosis and appropriate management. Status asthmaticus, however, is a potentially life-threatening manifestation of asthma in cats, especially if not recognized and treated appropriately in the emergency setting. Prevention is challenging, as it is impossible to truly prevent the onset of an allergic condition like asthma. Prevention and/or reduction of clinical signs can be achieved through avoidance of known aeroallergens.

Follow-up evaluation is necessary for successful chronic management of cats with asthma. Clinicians should decide whether to reduce a steroid dose based on clinical signs, physical examination, thoracic radiography, and, occasionally, resolution of airway eosinophilia. Long-term management of feline asthma is aimed at lowering glucocorticoid doses to the lowest effective dose that controls clinical signs and airway inflammation. Some patients may be transitioned to inhaled glucocorticoid therapy (eg, fluticasone) using a space chamber to aid drug delivery. Patients started on bronchodilator therapy can often be tapered off once airway inflammation is controlled.

Feline asthma patients are generally responsive to treatment with a glucocorticoid ± bronchodilator. In feline respiratory patients unresponsive to standard asthma therapy, the diagnosis should be reconsidered and further diagnostics pursued.

• Drug-induced response (eg, to vincristine, epinephrine, possibly a glucocorticoid)
• Iron deficiency
• Physiologic reaction
  • To epinephrine (eg, due to trauma, exercise, or excitement)
  • Postsplenectomy
• Primary thrombocytosis
  • Acute megakaryocytic leukemia
  • Chronic myeloproliferative disease
• Chronic basophilic leukemia
• Chronic myeloid leukemia
• Essential thrombocythemia
• Other myelodysplastic/ myeloproliferative neoplasm
• Polycythemia vera
• Primary myelofibrosis
• Pseudothrombocytosis
  • RBC ghosts or fragments, fragile leukocytes, microorganisms, or lipemia
• Reactive thrombocytosis
  • Hematopoietic/nonhematopoietic neoplasia
  • Hyperadrenocorticism
  • Infection
  • Inflammation (eg, immune-mediated or hepatobiliary disease)
  • Postsplenectomy
  • Rebound from thrombocytopenia
  • Trauma

The veterinary healthcare team is in an ideal position to help kittens mature into content, comfortable, and healthy adult cats. Owners are often unaware of the important role they play in their cats’ social development and typically do not ask clinicians for guidance on preventive behavioral care; thus, clinicians should proactively offer advice regarding the behavioral needs of kittens. By discussing normal kitten development, clinicians can be a primary source of accurate information and provide guidance when kittens exhibit problematic behaviors.

Although it can be helpful to consider kitten development as progressing through stages, the timeline is not rigidly based on chronologic age. Environmental factors (eg, early handling, opportunities to observe the queen, interactions with littermates) affect both physical and behavioral development.⁴ Kittens not routinely handled until 7 weeks of age may remain tentative and less interactive with humans.⁵

During the first days after birth, kittens experience the world mainly through olfaction and touch. Within 2 weeks, eyes are open; visual recognition becomes available, and social interactions increase in complexity. Coordinated motor skills begin to develop at this time; kittens begin to use their paws to interact with objects, and by 4 weeks of age, social play can be observed. By 7 weeks of age, play focus shifts from social play to object play.^6,7

At 4 weeks of age, kittens may be introduced to solid food. Weaning also typically begins around this time, when the mother may start to bring prey to teach kittens to hunt.^6,7

Socialization refers to the process during which kittens interact with and develop appropriate social behaviors toward other members of the same species. In practice, “socialization” is used more broadly and includes learning to interact with other social species and adjusting to relevant environmental stimuli.

A sensitive period is considered to be an age range in which external stimuli are particularly likely to have a long-term effect on development^6,7; the sensitive period for socialization in kittens is thus considered to be the period during which kittens form social attachments most easily and during which experiences—both positive and negative—have a greater long-term effect. This period occurs when kittens are between 2 and 7 weeks of age,^6,7 whereas the sensitive period for socialization in dogs extends from 3 to 14 weeks of age.⁸

Although the most sensitive period for kitten socialization is coming to a close by the time many kittens are adopted (ie, at ≈7 weeks of age), this does not mean that kittens should be adopted prior to 7 weeks of age. Kittens can benefit from watching the queen and interacting with littermates. Kittens raised without littermates are typically slower to learn social skills than normally reared kittens.⁶

Socialization does not stop abruptly at 7 weeks of age. Safe, comfortable exposure to important stimuli should continue regardless of when a kitten is adopted.

Puberty in kittens begins between 5 and 6 months of age.⁷ Cats are not socially mature until they are older than 1 year. As cats mature sexually and socially, new communication patterns (eg, mounting, marking such as urine spraying) may emerge.

Until kittens are 2 years of age, behavioral check-ups should be performed every 4 to 6 months to address and recognize concerns early. These check-ins are best accomplished by visits dedicated purely to social interaction in the clinic. Another option is to preschedule routine outreach phone calls; a brief 5-minute call may be of great value to preserve the human–animal bond. 

The first veterinary visit should occur when kittens are between 6 and 16 weeks of age. During this visit, it is important to conduct a thorough physical and behavioral examination while also addressing owner expectations.

The first well-care appointment is an opportunity to start a behavioral baseline for kittens. Owners should be asked about any kitten behavioral concerns. Behavioral handouts can be used to teach owners appropriate training and management techniques.

While history is being collected, kittens should be allowed to roam the examination room. Normal kittens will explore, engage with toys, accept treats, and interact with staff.

A kitten’s response to handling should also be noted. This is a kitten’s first impression of the veterinary experience. If a kitten is too nervous to eat treats or starts to struggle, it is critical that staff step back from the kitten rather than hold it tighter; a short break can often be enough to help kittens relax.

Kittens that are shy, do not play or explore, and/or are in apparent fear even with gentle and considerate handling should receive a customized socialization program and their owners given behavioral advice. Clinicians should not hesitate to refer kittens of any age to a boarded veterinary behaviorist.

A kitten’s normal behavior should be reviewed during the examination, and expectations shared by many owners—that their kitten must eliminate only in a litter box and scratch only on a scratching post—should be discussed. Most owners would like to be able to play with and pet their kitten without being bitten or scratched.

Owners typically choose kittens based on physical traits.⁹ Once the kitten is home, the owner will discover whether the kitten is affectionate, playful, fearful, active, and/or aggressive. Personality and behavior are strongly influenced by early environment, experiences, and genetics. By 7 weeks of age, some behavioral tendencies may not be readily changed.⁶ The owner’s goals for their kitten should be determined, and whether those goals are reasonable in light of behaviors observed during the examination should be discussed.

Behaviors such as elimination, scratching, and play should be discussed during each well-care appointment. Often, behaviors are developmentally normal but undesirable. Young kittens need supervision for their safety and to prevent them from engaging in undesirable behaviors. With appropriate information, owners can understand and prevent unwanted behaviors while encouraging preferred ones.

Elimination & Scratching Behavior

Even if a newly adopted kitten has used a litter box in a prior setting, the kitten may not be committed to an exclusive elimination area. Clean boxes should be provided in several locations. Another option for litter box training is to confine the kitten to a smaller space (eg, a single bedroom) with its litter box, especially when it cannot be closely supervised. Once the kitten begins to use the box consistently, more areas of the house can be made accessible. Large homes and multipet households need more than one litter box station.

Normal kittens scratch surfaces as they explore the environment. An assortment of horizontal and vertical scratching posts should be offered to kittens in prominent social areas. Until a substrate preference has been established, posts made from a variety of materials (eg, cardboard, sisal, fabric) should be provided.

If a kitten is caught eliminating or scratching in an undesirable location, the kitten can be distracted to interrupt the behavior; a toy or treat can be used to lure the kitten from the spot. The distraction should not be aversive. For kittens that likely need to eliminate, a food lure can be used as a guide to the nearby litter box. Shouting at or otherwise frightening a kitten, even once, can permanently destroy a kitten’s relationship with the owner.

Play

Normal kittens are playful. Play can include predatory sequences directed at objects, hands, and feet. A variety of toys, including puzzle games and interactive wand toys, should be offered. Kittens should not be invited or encouraged to play with hands or feet. If a kitten playfully pounces on a person, the kitten should be directed back to a toy. It should be expressed clearly to owners that shouting and spraying the kitten with water can create fear and/or arousal and are not appropriate ways to teach proper play.

Communication & Training

Feline body language should also be reviewed during the visit.⁷ Whether a kitten is being socialized with a stranger or is playing with a family member, it is important to discontinue the interaction if the kitten shows signs of fear or emotional arousal.

Communication can be further strengthened through reward-based training. During training sessions, kittens learn safe, predictable ways to interact with humans, and owners learn to attend to their cat’s body language. Punishment should never be used when training a kitten.

Kittens should be introduced to friendly, calm dogs; healthy, friendly cats; and quiet children. Kittens should be brought to other homes where they can explore and encounter assorted scents and sounds. Treats and toys should be offered to make the experience positive. Kittens should remain calm and interested, not overwhelmed.

Manipulations that may be required for husbandry and healthcare, as well as a variety of foods with assorted textures, should be introduced. Young kittens may still have flexible eating habits. Encouraging kittens to explore foods with assorted textures and flavors may improve willingness to eat a limited ingredient or prescription diet in the future.

Group “kitten kindergarten” sessions¹⁰ can be used to educate owners and socialize kittens in the clinic. Owners can be taught to administer topical and oral medications, while kittens can learn to accept a leash and harness.

For some kittens, every stimulus may seem overwhelming. Repeated exposure in the face of profound fear must be avoided, as it can lead to sensitization, which may not be reversible. It is never too early to address fear with behavior modification and, in some cases, pharmacologic intervention.

Clinicians are in a unique position to positively affect the social development of kittens, but the window of opportunity is narrow. Early, accurate behavioral advice increases the strength of the bond between the owner and kitten, improves the kitten’s ability to accept excellent medical care, and helps create a strong clinician–owner–patient relationship.

Chronic kidney disease (CKD) occurs in 30% to 40% of cats >10 years of age,¹ with 20% to 30% of these cats experiencing UTIs of either the lower or upper urinary tract.² Amoxicillin/clavulanic acid is commonly used in these patients. In humans with CKD, alterations in serum and urine concentrations of amoxicillin as well as clavulanic acid affect dose recommendations for this drug.^3,4

The first part of this study evaluated whether cats with azotemic CKD (azCKD) experienced increased adverse effects from amoxicillin/clavulanic acid as compared with cats without azCKD. Owners of cats that had been prescribed amoxicillin/clavulanic acid for any reason were surveyed. The results of the 61 returned surveys—representing 11 cats with azCKD (9 in IRIS stage 2) and 50 cats without azCKD—showed no significant difference in the prevalence of adverse effects, including vomiting, diarrhea, and decreased appetite. However, a significantly greater number of cats with azCKD experienced >1 adverse effect; clinicians were also more likely to adjust the treatment plan (eg, discontinue the antibiotic) in these patients as a result of these adverse effects.

The second part of this study determined the serum and urine amoxicillin and clavulanic acid concentrations in 6 cats with azCKD (5 in IRIS stage 2, 1 in IRIS stage 4) and 6 without azCKD that were receiving amoxicillin/clavulanic acid. Similar to humans with CKD, cats with azCKD trended toward higher serum concentrations of amoxicillin but had significantly lower urine concentrations of amoxicillin than did cats without azCKD. No significant difference was seen in clavulanic acid concentrations in either serum or urine, although the azCKD group trended toward higher serum levels.

These results should not be overinterpreted, as the study population size was small and the severity of CKD was restricted to those showing consistent elevations in creatinine, low urine-specific gravity, and ultrasonographic changes suggestive of renal disease. Conversely, these results should not be underestimated, as there were no cats in IRIS stage 3 and only 1 in stage 4 in this study population.

Key pearls to put into practice:

The lower end of the dose range should be used for amoxicillin/clavulanic acid for CKD patients with systemic conditions.

Although urine concentrations of amoxicillin may be lower, there is sufficient amount of the drug excreted in the urine for treatment of lower urinary tract disease in cats with early stages of CKD.

Adverse reactions to amoxicillin/clavulanic acid may be more common in cats with CKD and should be anticipated.

As with any decision to prescribe an antibiotic, it is critical the drug be effective against the infecting organism. To provide effective therapy and reduce the chance of antimicrobial resistance development, culture testing should be performed. When culturing is not feasible, amoxicillin without clavulanic acid is a reasonable first choice for sporadic or recurrent bacterial cystitis, depending on geographic sensitivity patterns.⁵

Canine degenerative myelopathy is a progressive, adult-onset neurodegenerative disease characterized by pelvic limb proprioceptive ataxia that progresses to paraparesis, then paralysis of the pelvic limbs, followed by thoracic limb paralysis. Treatment is limited to palliative therapy due to the lack of effective treatment options. This retrospective study evaluated the effect of 2 photobiomodulation therapy protocols on the progression of clinical signs of degenerative myelopathy. All dogs received the same twice-weekly in-clinic rehabilitation therapy and at-home exercise program. In addition, during in-clinic therapy, dogs received either photobiomodulation therapy protocol A (PTCL-A; n = 6) or photobiomodulation therapy protocol B (PTCL-B; n = 14). Results in the PTCL-B group showed significantly longer times between signs of onset and euthanasia as well as between signs of onset and nonambulatory paresis or paralysis as compared with the PTCL-A group; Kaplan–Meier survival analysis also demonstrated significantly longer time of clinical sign onset to nonambulatory paresis in the PTCL-B group as compared with the PTCL-A group and historical data group. These results suggest there may be potential benefits of using PTCL-B in combination with an intense rehabilitation therapy plan in dogs with degenerative myelopathy. A randomized, double-blinded placebo control prospective clinical trial is underway.

Diagnosis of cranial cruciate ligament (CCL) tears is made through a combination of orthopedic examination findings (eg, positive cranial drawer, cranial tibial translation) and radiographic changes (eg, effusion, osteoarthritic change). 

This study evaluated how well preoperative findings correlated with arthroscopic assessment of CCL fiber damage in 29 dogs with complete CCL tears. Patients were assessed while awake, under sedation, and under anesthesia. Most were found to have pain on stifle hyperextension and tibial internal rotation; CCL tear was associated with a reduced stifle range of motion. No correlation was found among degree of medial buttress, periarticular fibrosis, and palpable stifle laxity, whereas stifle laxity and degree of lameness were positively correlated. Dogs with high osteoarthritis scores on radiographs had less severe cranial drawer when awake, but this difference became insignificant when patients were sedated or under anesthesia.

The degree of CCL fiber damage was most correlated with the severity of lameness and with a positive cranial tibial translation test. Medial meniscal damage was most correlated with pain on internal rotation of the stifle and severity of radiographic osteophytosis. Cranial drawer was not significantly associated with degree of fiber damage or medial buttress. No association was found between degree of fiber damage and level of synovitis, effusion, or osteoarthritic change.

Key pearls to put into practice:

The degree of lameness in a dog with a CCL tear is associated with increased CCL fiber damage.

Pain on internal rotation of the stifle should raise suspicion of meniscal injury.

Assessments of dogs both awake and sedated can provide improved clinical information.

Cranial tibial translation under tibial compression may be more informative than cranial drawer examination.

Local anesthetics prevent painful impulses from reaching the CNS and are often recommended for patients with pain amenable to being controlled via local anesthetic blockades.^1-3 In addition to intraoperative analgesia (ie, antinociception during anesthesia), local anesthetics provide postoperative pain relief³; this is critically important because effective postoperative analgesics are limited. NSAIDs (ie, the main drug class used) are effective, but pain is not always controlled by NSAIDs alone and patients are not always hospitalized for treatment such as analgesic infusions. Local anesthetics administered preoperatively can be beneficial during the immediate postoperative period; however, maximum duration averages 2 to 8 hours.³ The exception to this is with liposomal bupivacaine (ie, liposome-encapsulated bupivacaine), which is FDA approved for use in both dogs⁴ and cats⁵ for ≤72 hours of analgesia. This drug can be used for a myriad of anesthetic blocks⁶ but has been underused, likely due to cost and the label limitation to discard any unused drug within 4 hours of vial puncturing, which increases drug waste and limits the ability to share drug cost among patients.

In the present study, the authors addressed 2 key concerns regarding the ability to extend the use of a punctured vial of liposomal bupivacaine: whether sterility is maintained and whether the liposomes degrade and release free (ie, unencapsulated) bupivacaine. Vials of liposomal bupivacaine (20 mL) were stored at room temperature (75°F [24°C]) or refrigerated (41°F [5°C]) and punctured for aliquot withdrawal each day for 5 days.

No bacterial or fungal growth occurred from any sample, except for a control vial that grew Aspergillus spp, a common environmental fungal contaminant; this vial was only punctured on the last day of sampling. The liposomes gradually degraded and released free bupivacaine, but the level was only significant on day 5, which led the authors to conclude that single-use liposomal bupivacaine handled aseptically could be used extra-label in a multidose manner for ≤4 days.

Refrigeration caused more rapid liposomal degradation, but even with degradation, the free bupivacaine in both groups remained below recommended dosages. Thus, overdose under these circumstances would not occur, but free bupivacaine would not provide 72 hours of analgesia.

Key pearls to put into practice:

Local anesthetic blockades should be considered for every surgical incision and traumatic lesion. Liposomal bupivacaine can be used in any patient and is particularly useful in those in which postoperative pain is unlikely to be controlled by NSAIDs alone and those that will not be hospitalized for analgesic infusions.

Extending the duration of use of a liposomal bupivacaine vial from 4 hours to 4 days is more cost-effective, especially in hospitals with small surgical caseloads, as the cost of liposomal bupivacaine can be shared among more patients.

The bottle top should be wiped with alcohol, and a small-gauge needle should be used to withdraw the drug. Unopened vials should be refrigerated, but slower liposomal breakdown has been shown to occur when opened vials are stored at room temperature.

To more realistically evaluate the cost of liposomal bupivacaine to the patient, the drug cost can be divided by the 72 hours of analgesia. When the label dose is administered, the current cost is ≈$0.05-$0.07/kg/hour to the clinician (before mark-up).

Liposomal bupivacaine is also available in 10-mL vials, which should further decrease cost and waste.

Norovirus is a common cause of acute GI disease in humans. Numerous norovirus strains have been identified and tend to infect different host species. Canine norovirus strains have been identified with unclear clinical relevance^1-4; however, human strains can also be found in dogs, raising zoonotic and animal health risk concerns.^5-7

During an investigation into an outbreak of acute gastroenteritis in a dog kennel, 2 children living in a household located on kennel premises had developed GI disease and were hospitalized. The children were diagnosed with norovirus infection and recovered uneventfully; however, over a period beginning 9 days after the children became ill, 2 dams that had been brought from the kennel into the house developed GI disease, as did 5 out of 6 puppies from one of the dams. Norovirus was detected in the feces of all the sick dogs. Whole-genome sequencing of samples from 2 dogs and the 2 children was performed. The human and canine viruses were virtually identical and identified as the human-associated genotype GII-4.

Key pearls to put into practice:

Human norovirus is a potential but likely rare enteropathogen in dogs.

Humans with norovirus infection should follow good infection-control practices to prevent transmission to humans and animals.

The risk posed by dogs owned by humans with norovirus is unknown, as the prevalence of norovirus shedding in dogs belonging to infected humans has not been adequately investigated. Because infected dogs can shed human norovirus for ≥1 weeks, good hygiene practices, especially hand hygiene and proper fecal handling, should be emphasized around diarrheic dogs and dogs that have had contact with humans with norovirus infection.

Common injuries following blunt thoracic trauma include pulmonary contusion, pulmonary laceration, pneumothorax, hemothorax, and rib and sternal fractures and subluxations. Thoracic injuries are commonly overlooked when distracting injuries (eg, limb fracture) are present or when thoracic radiographs are acquired immediately after the injury occurs, as thoracic injuries may take more time to appear.^1,2 Approximately one-third of dogs with limb fracture (thoracic or pelvic) due to collision with a motor vehicle also have radiographic evidence of thoracic trauma.¹ Air and fluid accumulation in the pleural space may be evident within minutes or may take hours to become apparent, depending on the size and rate of the fluid or air leak. Pulmonary contusions may take ≥4 hours to appear radiographically.²

CT imaging is routinely performed in humans and is directly responsible for treatment plan alterations in 20% to 34% of trauma patients.^3-5

Because CT is not as widely available to veterinarians, this study sought to determine if parameters from arterial blood gas and acid-base status could predict the type and degree of thoracic pathology in place of a CT scan in dogs with blunt thoracic trauma.

Dogs presented with respiratory changes and/or fractures within 48 hours of being struck by a motor vehicle were eligible for study inclusion. Patients in severe respiratory distress that required intervention were excluded. In total, 31 patients were included and underwent CT scan and arterial blood gas evaluation ≥4 hours after injury and within 24 hours of presentation. Each patient was assigned a trauma triage score, and each CT scan was evaluated and scored using a novel scoring system. Arterial blood gas values and acid-base status were compared with values obtained from a control group of 15 healthy dogs.

Concordance between CT findings and blood gas/lactate values was found; however, inclusion of these values did not change diagnosis or treatment recommendations in patients with significant CT lesions. Acid-base imbalances in this study were generally found to be mild, insignificant, and variable.

Key pearls to put into practice:

Patients with blunt trauma should be evaluated for pulmonary contusions, air and fluid in the pleural space, and rib fractures or dislocations.

A combination of thoracic imaging and respiratory parameters should be evaluated, as each variable alone fails to provide a complete picture.

Patients with a combination of thoracic injuries are more likely to have worse oxygenation abnormalities as compared with patients without a combination of injuries; these abnormalities are likely to evolve and change over several hours.

Cutaneous mast cell tumors (MCTs) are common and diverse in clinical appearance and behavior and account for ≤20% of skin cancers in dogs.¹ Predicting this seemingly unpredictable behavior is challenging.

Histopathologic grade and mitotic index are the most common factors used in predicting prognosis^2-5; however, there are several shortcomings if these criteria are used alone. The 3-tier (ie, Patnaik) system is criticized for its subjective grading criteria.^6,7 The 2-tier (ie, Kiupel) system uses more objective grading criteria,⁵ but studies evaluating this system have indicated several significant limitations.⁵

Considering the limitations of these grading systems, this study hypothesized that a subset of dogs with localized Kiupel high-grade cutaneous MCTs may have a better outcome than suggested by the original literature.^2,5,8,9 In this retrospective study, the outcomes and prognostic factors for dogs with Kiupel high-grade cutaneous MCTs presented without overt metastasis were evaluated. All dogs received curative intent surgical excision of the MCTs, with or without chemotherapy.

A total of 49 dogs were evaluated. Some dogs were not completely staged, although lymph nodes were reported to be of clinically normal size in all dogs. Forty-five MCTs were histologically completely excised. Three of the 4 dogs with histologically incomplete margins underwent re-excision. Chemotherapy (with a variety of protocols) was recommended for all dogs, but only 33 dogs received this treatment.

Local tumor recurrence developed in 9 (18.4%) dogs at a median of ≈158 days postoperation. Regional lymph node metastasis was diagnosed via cytology in 6 (12.2%) dogs at a median of ≈273 days postoperation. New MCTs developed in 15 (30.1%) dogs at a median of ≈495 days postoperation.

Median survival time (MST) for all 49 dogs was 1046 days, with 1- and 2-year survival rates being 79.3% and 72.9%, respectively. Dogs with MCTs with mitotic counts <15/10 hpf had a longer MST (1645 days) as compared with dogs with MCTs with mitotic counts ≥15/10 hpf (162 days). Dogs with smaller tumors (<25 mm) had an improved MST (1645 days) as compared with dogs with larger tumors (≥25 mm; MST, 252 days). Chemotherapy did not appear to improve survival in this study.

This study suggests that the prognosis for dogs with clinical stage 1 (ie, no overt metastasis at time of initial diagnosis), Kiupel high-grade cutaneous MCTs receiving good local tumor control (ie, complete excision) is good, especially for those with low mitotic index and smaller tumor sizes.

Key pearls to put into practice:

Adequate surgical control of solitary Kiupel high-grade MCTs may provide longer survival time, especially for dogs with tumors <25 mm and mitotic counts <15/10 hpf.

Grade alone should not be used to predict outcome in these patients; clinical stage and selected treatment also contribute to the outcome.

Full clinical staging, specifically regional lymph node histopathology, is recommended for dogs with Kiupel high-grade MCT.

Sponsored by Trudell Medical 

Juvenile sterile granulomatous dermatitis and lymphadenitis (SGDL) is an uncommon idiopathic sterile inflammatory disease most commonly seen in puppies and referred to as juvenile cellulitis or puppy strangles. Classic clinical features include facial swelling and pustular dermatitis of the periocular skin, pinnae, and muzzle. Lesions can be less common elsewhere. Disease typically affects younger dogs ranging from a few weeks to a few months of age. There have been a couple reports of the disease developing in older dogs, but this is the first extensive case series examining SGDL in adult dogs.

This case series included 90 dogs with biopsy results consistent with SGDL. The median age of onset was 3.54 years, although ages ranged from 1 to 11.4 years. Clinical signs on presentation were found to be similar to those of young dogs, with lesions consisting primarily of edema, ulceration, erythema, crusting, and pustules, primarily of the periocular skin, muzzle, lips, and pinnae. Lesions were also observed on the perianal/genital area and other areas; lymphadenopathy was noted in 33.3% of cases. Systemic signs included lethargy, fever, and hyporexia. All dogs that had drug treatment records available (35/90) were treated with systemic glucocorticoids. Mean glucocorticoid dose, given as prednisone equivalent, was 1.23 mg/kg/day. Antibiotics were frequently coadministered, likely for secondary infection. Median treatment duration was 60 days (range, 20-1825 days), and median time to remission was 28 days. Remission was maintained in 19/30 dogs for which remission status was known. Relapse was noted in 11 of these 30 dogs.

Key pearls to put into practice:

Despite being known as juvenile cellulitis and puppy strangles, SGDL is not just a disease of puppies. Adult and geriatric animals can be presented with this disease; SGDL should be on the differential diagnosis list for dogs of all ages.

Immunosuppressive doses of steroids are the treatment of choice for SGDL, regardless of patient age. Once remission is achieved, steroids should be tapered and eventually discontinued. Most patients with SGDL can be successfully weaned from steroid therapy, although recrudescence is not uncommon.

Biopsy remains the best way to achieve definitive diagnosis. Although SGDL can display a classic clinical presentation, biopsy is required to rule out other diseases, which is critical in older patients, as this is a less common presentation of SGDL. Definitive diagnosis is necessary prior to initiating therapy with immunosuppressive doses of steroids.

Feline corneal sequestrum is poorly understood, can cause significant discomfort, and may lead to corneal perforation and loss of vision. Feline corneal sequestrum should be recognized quickly and, in most patients, treated surgically. There is no consensus on a gold standard surgical procedure, suggesting that a single surgical option may not suit all patients.

This study reviewed medical records of 16 cats diagnosed with corneal sequestrum and treated with lamellar keratectomy and cyanoacrylate adhesive. Following keratectomy, a single drop of cyanoacrylate was placed on the corneal surface and painted into the defect to form a continuous layer covering the entire keratectomy site. A bandage contact lens was then placed once the adhesive polymerized; median procedure time was 10 minutes. 

Patients were treated postoperatively with topical antibiotics, lubricants, and pain medication, ± antiviral medication; rechecks were performed at 1 and 3 weeks postoperation and later if necessary. Medications were discontinued once the cyanoacrylate was no longer present and the defect had completely healed; median time to cessation of topical medications was 4 weeks. Recurrence rate was 13%, similar to other reported surgical techniques for corneal sequestrum. Purebred status was the only significant factor in cats that experienced recurrence. No significant complications were seen.

Key pearls to put into practice:

In addition to traditional grafting procedures (eg, conjunctival pedicle grafting, corneoconjunctival transposition), the clinician should be aware of an alternative surgical approach using cyanoacrylate adhesive. Pet owners should be educated that this is a safe and successful adjunctive therapy to lamellar keratectomy in cats with midstromal corneal sequestra. Recurrence rates are similar to those seen with traditional grafting procedures.

Corneal sequestrum treated with keratectomy and cyanoacrylate adhesive appears to have a low complication incidence; no postoperative infection, keratomalacia, corneal perforation, or other complications were reported in this study. This procedure may be more time efficient than previously described procedures and may provide benefits of decreased anesthesia time, shorter postoperative treatment duration, and, potentially, lower procedure costs.

Proper magnification and microsurgical instruments should be used for the lamellar keratectomy that precedes application of the cyanoacrylate adhesive.

With an increased focus on healthcare-associated infections, including multidrug-resistant pathogens, there is greater emphasis on environmental transmission and a need for methods to validate cleaning and disinfection programs in human and veterinary hospitals. This study, conducted at a university small animal teaching hospital, used a fluorescent tagging method to assess environmental cleaning practices across numerous surfaces and locations. Overall total cleaning success was only 50%, with surfaces categorized as primarily animal contact having a better cleaning rate (74.9%) than did surfaces designated as primarily human contact (41.7%). This low-cost method could be employed regularly to improve veterinary hospital cleaning practices.

Companies that are more diverse and inclusive are more profitable, tend to be better able to attract top talent, demonstrate higher employee satisfaction, see better decision-making within the company, and even connect better with pet owners.^2-4

The benefits of diversity do not appear to accrue to companies with demographic diversity alone⁵; inclusion—such as the creation of an environment that allows all people to fully participate and feel valued, respected, and supported—is important. Benefits emerge not just from the presence of people with different backgrounds and perspectives but by welcoming those differences, too.

Supporting diversity and inclusion is vital for the practice of high-quality care in a healthcare setting as well.^1,6 Clinics that embrace diversity and inclusion can improve communication with owners, better understand cultural attitudes or practices that may affect patient care, and provide a more positive work environment.^1,3 Banfield Pet Hospital in particular emphasizes diversity and inclusion as core to health and well-being.

Navigating the job market to find practices that best incorporate ideals of diversity and inclusion can be difficult, but it is possible to look for hints in the interview process, mission statements and policies, employee benefits, and more.

The interview process can help determine how diverse or inclusive a clinic may be; interviews that ask questions specific to race, gender, religion, marital status, and sexual orientation should be red flags. In addition, it should be determined if a clinic has set plans and policies in place for inclusion and diversity^3,4,7; this creates structure and avoids confusion while also emphasizing and setting an example for staff on the importance of these principles.⁴ Policies can include conflict management, health and ability accommodations, and antidiscrimination tactics, among others⁴; for instance, Banfield Pet Hospital provides gender neutral signage.

Mission statements and practice values can also be a measure of how the practice promotes inclusion and diversity.^3,7 Employee benefits can be another area reflective of inclusion—not only for employees but for the employee’s spouses and family members as well.⁴ Sick time, breastfeeding availability, religious holidays, and flexible leave are all measures that encourage inclusiveness.⁴ Full-time Banfield employees have partial paid leave for illnesses, pregnancy, and other unexpected life events.

Who fills leadership roles within the practice can also be evaluated. Decision-making members of the team should ideally represent staff and clients.^2-5 Banfield Diversity Resource Groups (DRGs) create supportive, engaging environments to develop and elevate team members; these groups are one way practices can sustain additional efforts to promote diversity and inclusion. The 5 initial DRGs at Banfield include Women, Next Gen, Unidos, POWER, and Pride, with Asian and Island Pacific being a recent addition. As with the Banfield DRGs, practices can also invest staff time or focus staff positions on diversity and inclusion.

Not only should team members feel included, but a diverse client base should be acknowledged and celebrated as well. Providing brochures and clinic artwork that represent the clientele and delivering information in the language clients are most comfortable with are important; hiring and technology are 2 ways practices are addressing these challenges. Banfield has launched a service that provides clients with over-the-phone interpretation in 350+ languages.

Practices can leverage technology to improve diversity and inclusion in other ways as well. Not only can technology increase options for non-native–English speakers but also for the hearing or visually impaired. Electronic records and patient portals similarly increase accessibility. Flexible communication provides collaboration between colleagues in addition to client communication. In addition, hiring software is increasingly evaluating job ads and applications to fight nepotism or discrimination in recruiting.

Banfield has laid a foundation and future vision for an inclusive culture in which their associates can thrive. Considering the benefits to both veterinary teams and patients, it is worthwhile for veterinarians to look for key factors that signal practice values not just representing local demographics but a true culture of diversity and inclusion.

Surgical site infections remain a costly issue that increases morbidity and sometimes mortality in veterinary patients. To minimize surgical site infections, antibacterial-coated suture materials are available for use in human and veterinary patients. Triclosan-coated suture materials have been tested in human medicine and are recommended by the World Health Organization; limited testing has been performed in veterinary patients.

In this study,* triclosan-coated polydioxanone (monofilament), poliglecaprone-25 (monofilament), and polyglactin-910 (multifilament) were tested in vitro for effectiveness against clinical isolates from canine wound infections: methicillin-resistant Staphylococcus pseudintermedius, methicillin-susceptible S pseudintermedius, Escherichia coli, and AmpC β-lactamase– and extended-spectrum β-lactamase–producing E coli.

Isolates were cultured on Mueller-Hinton agar with the 3 types of triclosan-coated suture as well as with uncoated counterparts of the same suture types. Zones of inhibition were measured after overnight incubation, and sustained antimicrobial activity assays were performed with susceptible isolates. The coated monofilaments performed best against all bacterial strains, with the greatest zones of inhibition and the longest duration of antibacterial action as compared with either polyglactin-910 suture (ie, triclosan-coated and non-triclosan–coated).

Triclosan-coated suture was more effective against staphylococcal isolates than against E coli isolates, both in zones of inhibition and duration of antimicrobial effect. E coli possibly requires a higher concentration of triclosan than do staphylococcal isolates. Coated and uncoated poliglecaprone-25 and polydioxanone had the least bacterial adherence when scanned under electron microscopy as compared with braided polyglactin-910. Polydioxanone had a slight increase of adherence by E coli, possibly due to its characteristic surface ridges appreciated when scanned with electron microscopy; this suggests the surface characteristics of sutures may be as significant as an antibacterial coating in combating bacterial colonization of the suture.

Key pearls to put into practice:

Braided suture materials are more prone to bacterial colonization than monofilament materials and should be avoided in infected or contaminated surgical wounds or in wounds in which infection could be catastrophic (eg, joints, implants). The increased surface area and intertwining nature of multifilament suture provides more interstices for bacteria to harbor.

Comfort is a benefit of braided suture. Absorbable, braided material (eg, polyglactin-910) can be used safely in superficial mucosa, gingival, and periocular skin closure, as these sutures are gentler in regions where monofilament sutures might be abrasive.

Triclosan-coated suture material can be helpful in regions where infection is present or where the effects of infection would be especially deleterious. However, proper surgical technique, adherence to Halsted’s principles, and proper selection of suture based on its inherent characteristics is critical and likely more important than the use of antibacterial-coated suture.

In heavily contaminated or infected wounds, suture material that degrades rapidly after the required time for healing is highly desirable. This decreases the load of foreign material that WBCs must handle, allowing bacterial degradation and tissue healing. Shorter-acting suture material is less likely to provide a scaffold for morbidity-increasing biofilms.

There is no benefit to using a suture that is stronger than the tissue it is used in. Sutures that persist longer than necessary can increase morbidity at any surgery site.

Cat allergies affect 1 in 5 adult humans worldwide and are a major risk factor for development of asthma and rhinitis. New approaches for management are needed, as allergen avoidance can be stressful or emotionally trying for owners, and allergen immunotherapy has not been well demonstrated. This novel care pathway evaluated a feline diet with an egg-product ingredient containing anti-Fel d 1 IgY antibodies to safely neutralize Fel d 1 in cats prior to human exposure. Efficacy was demonstrated in vitro, ex vivo, and in vivo and validated by a pilot study using cat-allergic human subjects.

Ventral midline celiotomy is common in veterinary practice. Potential complications related to the celiotomy incision include seroma formation, excessive inflammation, and surgical site infection (SSI). Although complications are uncommon, they can have devastating consequences and may require prolonged antimicrobial treatment and/or revision surgery. Clinicians should be aware of any precautions to limit incision complication potential and obey Halsted’s principles.

Seroma formation has been associated with SSIs in humans.¹ The use of a quilting pattern for SC closure (ie, tacking SC tissue to the rectus fascia every third pass) has been shown to reduce the risk for seroma formation in humans and dogs, as this technique reduces the potential dead space that forms following the ventral midline surgical approach.^2,3

This single-center, randomized, blinded, controlled trial was conducted in cats undergoing ventral midline celiotomy to compare the effects of SC closure on seroma formation, postoperative pain severity, SSI incidence, incisional dehiscence, and closure time.

The researchers found that a quilting pattern reduced the incidence of seroma formation in cats undergoing ventral midline celiotomy by ≈50%, with minimal increase in surgical time. The quilting pattern was compared with a simple continuous closure pattern of SC tissue, in which no bites of the rectus fascia were taken, and compared with no closure of SC tissue (ie, an intradermal suture pattern was applied following linea alba closure). Both methods of SC closure reduced postoperative pain as compared with no SC closure; however, there was no significant difference between simple continuous appositional closure and a quilting suture pattern. There was no difference in the incidence of SSIs or incisional dehiscence between treatment groups.

Key pearls to put into practice:

A quilting suture pattern can be considered after ventral midline celiotomy in cats to reduce seroma formation and postoperative pain.

Pet owners should be aware of potential postoperative wound complications, as early diagnosis and treatment is critical.

A quilting suture pattern should not be a substitute for strict aseptic technique or the remaining Halsted’s principles.

Following are 5 of the most common causes of passive cervical flexion in cats and dogs (for additional differential diagnoses in cats, see Additional Differential Diagnoses for Passive Cervical Flexion in Cats).

Hypokalemic myopathy has been reported secondary to several disorders^1-11 (see Common Causes of Hypokalemia) and can occur in cats and dogs of any age but is more common in older animals.^3,5 Patients are often presented with stiff–stilted gait, weakness, exercise intolerance, cervical flexion (especially in cats), and muscle pain.^1-11 Cervical flexion due to hypokalemia (see Video) is common in cats but uncommon in dogs.¹ Delayed to absent postural reaction deficits and reduced patellar and withdrawal reflexes may be present depending on the severity of weakness. Muscle pain is occasionally noted.

Diagnosis in patients with compatible clinical signs of hypokalemia (<3.5 mEq/L) is relatively straightforward.^2-6 Serum creatine kinase (CK) levels are often moderately to markedly elevated.^2-6 Patients with chronic kidney disease (CKD) are likely to have elevated BUN and creatinine levels with concurrent isosthenuria, and although CKD can be a separate differential diagnosis for cervical flexion, it is often a result of potassium loss in the urine. Thoracic radiography and abdominal ultrasonography can be used to identify signs of CKD, adrenal neoplasia (eg, aldosterone-secreting tumor), and metastatic disease. Electrodiagnostic testing and nerve and muscle biopsy can be performed but are often unnecessary, except in complicated cases.

Treatment consists of potassium supplementation and correction (eg, adrenalectomy) of the underlying cause. Patients with moderate to severe hypokalemia (<3 mEq/L) should be administered potassium chloride in IV fluids—not to exceed 0.5 mEq/kg/hour except in life-threatening circumstances—and ECG should be closely monitored. Dogs and cats with mild hypokalemia or potassium levels that have been normalized with IV fluid supplementation should be administered potassium gluconate (2 mEq/4.5 kg body weight PO with food every 12 hours, adjusted as necessary).⁶ The dose should be titrated as indicated by serial potassium levels. Hypokalemia-induced cervical flexion tends to resolve quickly with potassium supplementation. Overall long-term prognosis is variable and depends on the inciting cause of hypokalemia.

Thiamine (ie, vitamin B1) is a water-soluble, heat-labile vitamin that is crucial to carbohydrate metabolism. Dogs and cats are unable to endogenously synthesize thiamine, so it must be obtained from the diet.^12-14 Although the risks for thiamine deficiency are well-known, inadequate supplementation can result from manufacturing or storage errors; during manufacturing, thiamine can be easily destroyed by high temperatures, chlorinated water, and/or being in a neutral or alkaline state. Manufacturers must compensate for this potential loss by adding high levels of thiamine to food. In addition, thiamine content declines with long-term storage because of the combined effects of heat and humidity. A recent report described 17 cats with thiamine deficiency that were fed the same commercial dry cat food.¹⁵

Thiamine deficiency can occur in dogs and cats of all ages and breeds. Thiamine deficiency is often seen in dogs with severe or end-stage liver dysfunction because the liver is a storage center for thiamine. Cats are more commonly affected than dogs due to their 3-fold higher dietary thiamine requirement (see Common Dietary Causes of  Thiamine Deficiency).¹⁶ Clinical signs in cats typically include nonspecific signs of inappetence, weight loss, vomiting, and diarrhea, as well as neurologic signs of generalized weakness, cervical flexion (Figure 2), central vestibular dysfunction, and dilated pupils.^17,18 Clinical signs in dogs include nonspecific signs of depression, inappetence, weight loss, vomiting, mental dullness, weakness, and seizures.¹³ Severe untreated thiamine deficiency can lead to coma and death in both species.

Definitive diagnosis is difficult because several forms of thiamine exist in the body and no single laboratory test measures all forms. A presumptive diagnosis is typically made based on compatible clinical signs, history of dietary changes (as described), and response to treatment. Routine laboratory test (eg, CBC, serum chemistry profile, urinalysis) results are usually normal.¹² MRI performed in patients with CNS signs may demonstrate bilaterally symmetrical T2-weighted hyperintense lesions in the lateral geniculate nucleus of the thalamus, caudal colliculi in the midbrain, and/or vestibular nuclei in the medulla.^19,20 CSF is usually normal.

Therapy should be focused on thiamine replacement and feeding a high-quality diet rich in thiamine. Limited data exist regarding an ideal dose, but ranges of 25 to 150 mg for cats and 100 to 600 mg for dogs have been described^17-23; daily IM thiamine injections for 3 to 5 days are recommended, followed by PO supplementation for 2 to 4 weeks.^17-23 Resolution of cervical flexion may take up to several weeks, but prognosis is good to excellent if the condition is diagnosed and treated early.

Hyperthyroidism is the most common endocrinopathy of middle-aged and older cats and is most often the result of excessive circulating levels of thyroxine (T₄) and triiodothyronine (T₃) produced by a thyroid adenoma or hyperplastic adenomatous thyroid tissue.^24-28 Thyroid carcinoma as a cause of hyperthyroidism is rare.²⁴

Clinical signs include weight loss (despite polyphagia), hyperactivity, polyuria/polydipsia, unkempt hair coat, GI signs (eg, vomiting, diarrhea), panting/dyspnea, lethargy or mental dullness, neuromuscular weakness, anxiety, nervousness, and/or behavior changes. Physical examination may reveal a thin cachectic cat, a palpable thyroid nodule, a heart murmur, tachycardia, arrhythmia, tachypnea, alopecia or unkempt hair coat, aggression, or mental dullness.^24-28 Cervical flexion and generalized muscle weakness occur in some cats with hyperthyroidism. Hyperthyroidism can also cause a vascular lesion in the cervical spinal cord of some cats that results in cervical flexion. In a study, concurrent hypokalemia was reported in 4 hyperthyroid cats with cervical flexion,²⁹ but the cause of hypokalemia was undetermined.

Diagnosis for most cats is made through measurement of elevated total T₄ (TT₄) by radioimmunoassay, but ≤10% of hyperthyroid cats have normal TT₄ during initial testing; these cats are in the early stage of disease and either TT₄ has not risen above the high-end normal limit or nonthyroidal illness is artificially lowering the TT₄ level.^24,25,30-33 Free T₄ should not be used as the sole screening test for hyperthyroidism because it is more sensitive and less specific than TT₄, causing more false-positive results.^31,34

Treatment options include medical management with thioureylene antithyroid drugs (eg, methimazole), low iodine diet, radioactive iodine (I-131) therapy, and thyroidectomy.³⁵ Methimazole (2.5 mg/cat PO every 12 hours) is most frequently used in the United States.³⁵ Serum TT₄ is measured 4 weeks later and the dose is gradually increased or reduced based on the results of repeated TT₄ testing.³⁵ Adverse effects include GI effects (eg, vomiting, anorexia), nonspecific signs (eg, depression, lethargy), blood dyscrasias (eg, thrombocytopenia, leukopenia, eosinophilia, lymphocytosis), pruritus and facial excoriations, and hepatopathy (rare).³⁵ It is recommended that medical management with methimazole be attempted prior to more advanced treatment in order to screen for underlying CKD, which can be masked by hyperthyroidism secondary to increased glomerular filtration rate and decreased serum creatinine concentration.³⁵

I-131 is the most effective option and the treatment of choice; it is typically safe and simple to administer but only available at specialized licensed facilities.³⁵ I-131 is concentrated in the thyroid glands, where it emits β particles and γ radiation that destroy functional hyperplastic thyroid tissue.³⁵ Thyroidectomy can be curative and may be performed when I-131 is not readily available.³⁵ Anesthesia can cause the secondary metabolic, renal, and cardiac changes to elevate the American Society of Anesthesiologists status and increase the risk for perioperative complications. Thyroidectomy is required for patients with thyroid carcinoma (rare).³⁵

Myasthenia gravis (MG) is a disorder of the neuromuscular junction and is either congenital or acquired. Congenital MG comprises a rare group of disorders characterized by failure of neuromuscular transmission due to inherited abnormalities of presynaptic, synaptic, or postsynaptic components.³⁶ Acquired MG is an autoimmune disorder caused by antibodies (most often immunoglobulin G) directed primarily against nicotinic acetylcholine receptors (AChRs) on skeletal muscle.³⁶ Functional loss of AChRs at the neuromuscular junction occurs via 3 possible mechanisms: complement-dependent lysis of the muscle membrane, cross-linking of AChRs leading to internalization of AChRs and decreased AChR half-life, and direct inhibition of AChR function by autoantibodies.³⁶ A small percentage of patients have antibodies against other muscle proteins (eg, muscle-specific receptor tyrosine kinase, titin, ryanodine receptor). Methimazole is a potential cause of drug-induced MG in cats.³⁷ Coexisting polymyositis has also been reported in cats.³⁶

Abyssinian and Somali cats have a higher incidence of MG as compared with other breeds and crossbreed cats.³⁷ Studies have found no sex predisposition. In a study, the average age of onset of clinical signs in 235 cats was 8.6 years (range, 6 months-15.4 years).³⁸ Clinical signs of MG in cats are similar to those in dogs and include generalized weakness without regurgitation or dysphagia (50%), generalized weakness with regurgitation or dysphagia (40%), and focal MG with regurgitation or dysphagia without generalized weakness (10%).³⁸ Facial weakness appears to be more common in cats.³⁸ Megaesophagus and regurgitation are less common in cats because their entire esophagus is composed of smooth muscle. Cervical flexion has been reported in 20% of cats with acquired MG.³⁹

Routine laboratory test (eg, CBC, serum chemistry profile, urinalysis) results are usually normal. Cats with MG are more likely to have a thymoma than dogs.^38,40 A study identified a cranial mediastinal mass in 52% of cats with acquired MG that underwent thoracic radiography.³⁸ A thymoma was identified in 97.7% of myasthenic cats that had a cranial mediastinal mass and underwent fine-needle aspiration.³⁸ A large study of dogs with acquired MG identified thymoma in only 3.4% of affected dogs.⁴⁰

The AChR antibody titer test, which is sensitive and specific, is considered to be the gold standard for diagnosing acquired MG.³⁶ An edrophonium challenge test can be used as a screening tool; however, it lacks sensitivity and specificity, and edrophonium is no longer produced. A neostigmine challenge (40 µg/kg IM or 20 µg/kg IV) can be performed and the patient observed for improved strength.³⁶ Electrodiagnostic testing (ie, repetitive nerve stimulation or single-fiber electromyography) or, in rare cases, immunohistochemical evaluation of junctional AChRs in whole-muscle biopsy specimens may be necessary to definitively diagnose acquired MG.³⁶

Treatment in cats involves pyridostigmine ± immunosuppressive therapy. Cats seem to be more responsive than dogs to corticosteroids, which may be the only treatment needed.³⁶ Thymectomy is recommended for cats that do not have evidence of local invasion or metastasis. Surgery may enable long-term survival and potentially be curative, but recurrence is possible.⁴¹

The prognosis for myasthenic cats appears to be worse than for dogs; 58% of cats in a study were euthanized because of the disease.³⁸ In cats, there is a negative correlation between AChR antibody titer levels and survival; thus, cats with higher titers have a worse prognosis.³⁸

Idiopathic polymyositis is a noninfectious, presumably immune-mediated, inflammatory myopathy in dogs and cats that can manifest as a generalized disorder or affect smaller muscle groups (eg, laryngeal muscles, extraocular muscles).⁴² Etiology has not been determined.

Although idiopathic polymyositis can occur in dogs and cats of all ages and breeds, predisposition has been reported in large-breed, adult, and older dogs.^42-44 Clinical signs include exercise intolerance, stiffness, short-strided gait in all 4 limbs with a tiptoe appearance (ie, walking on eggshells), and lordosis.⁴² Involvement of the laryngeal muscles may cause dysphagia, dysphonia, or stridor.⁴² Cervical flexion is uncommon and may be passive due to neuromuscular weakness or active due to muscle pain.⁴²

Although there are strict criteria for diagnosing idiopathic polymyositis in humans, these have not been defined in veterinary medicine. However, meeting at least 3 of the following criteria may strongly support a diagnosis⁴²:

• Appropriate clinical signs
• Elevated serum CK
• Abnormal electromyography with normal motor nerve conduction
• Negative infectious disease and autoimmune titers
• Inflammatory muscle biopsy

Serum chemistry profiles frequently demonstrate moderate to marked CK elevation and elevated ALT.^43,45 Thoracic radiography is recommended to screen for megaesophagus even if there is no clinical evidence of regurgitation.⁴² Electromyographs often appear abnormal (eg, fibrillations, positive sharp waves, complex repetitive discharges), especially in the proximal appendicular muscles.^42,45 Muscle biopsy of 2 muscle bellies is recommended. Histologic evaluation typically reveals mononuclear inflammation, necrotic muscle fibers with cellular infiltrates, and myofiber necrosis.⁴⁵

Treatment consists of immunosuppression, pain relief, and supportive care for megaesophagus and aspiration pneumonia, if present. Immunosuppressive doses of corticosteroids are standard (ie, prednisone [dogs]/prednisolone [cats], 2 mg/kg PO every 12 hours for 2-3 days, then 1 mg/kg PO every 12 hours for 2 weeks)⁴² and should be gradually tapered to the lowest effective dose over several months based on response to treatment. Other immunosuppressants (eg, cyclosporine, azathioprine [dogs only]) may be required if clinical signs do not resolve or if adverse effects are intolerable to the patient or owner. Prognosis is good for patients without megaesophagus. Long-term, possibly lifelong, treatment may be necessary.⁴²

Passive cervical flexion is a common abnormal body posture. The differential diagnosis list is relatively short, and diagnosis can typically be made easily. Passive cervical flexion must be differentiated from active cervical flexion because the differential diagnoses and neurologic examination findings are significantly different.