Table of Contents and Abstracts

Our objective was to provide preliminary clinical and laboratory data and the minimum effective dose for long-term (≥ 7 mo) treatment of feline allergic pruritus with oclacitinib. We studied 14 privately owned cats with pruritic allergic dermatitis controlled with oclacitinib treatment. Clinical data and results of blood testing (at the onset and at least once thereafter) during treatment were retrospectively evaluated. The median initial dosage of oclacitinib was 1.1 mg/kg q12h. In 7 animals, the maintenance dose could be reduced by ≥ 50%, usually after 15 d of treatment. The median duration of treatment was 15.5 mo. An FeLV-FIV test was conducted in 10 cats and all were negative. During treatment, 4 cats had non-dermatologic disorders that resolved without changing the oclacitinib dosing schedule. Alterations in blood tests during treatment were mild and frequently transient and included hypercholesterolemia, increased alanine aminotransferase and/or creatinine, and hyperglycemia. Limited and transitory disruptions in platelets and white cell lineage numbers were identified in some cats but none required specific treatment or discontinuation of oclacitinib. Alterations observed in the 14 cats treated with oclacitinib for a median of 15.5 mo were few and mild. No direct relationships were apparent between laboratory abnormalities or clinical signs and the dosing schedule of oclacitinib. A reduction of the daily dose to control allergic pruritus was feasible in 7/14 cats.

Key clinical message:
Based on the 14 cases included, long-term treatment with oclacitinib appeared to be well-tolerated and effective for managing feline allergic pruritus. However, close monitoring is recommended, and prospective studies with larger samples are needed to confirm these results.

Feline demodicosis is a rare parasitic skin disease. The clinical signs, which may range from mild and localized to severe and generalized, include alopecia, erythema, macules, pruritus, and hyperpigmentation. Although many studies have evaluated the safety and efficacy of different miticidal agents for canine demodicosis, there have been no controlled or conclusive studies on feline infection. Recommended medications for cats include organophosphates, lime sulfur, some macrocylic lactones, and isoxazolines, which may be administered as rinse, injection, oral or spot-on formulations. Most of these treatments are poorly tolerated by cats and have been associated with some adverse effects leading to treatment failure. Isoxazolines including sarolaner and fluralaner were introduced to veterinary medicine in 2014 and have gained remarkable popularity due to the rare occurrence of side effects with these treatments. However, literature reviews reveal only a few published reports of the effectiveness of this medication class on Demodex infestation in cats. To the authors’ knowledge, this case report documents the first successful treatment of the generalized form of demodicosis caused by D. cati in a cat achieved with 2 monthly doses of topical application of sarolaner-selamectin combination. This may be a useful reference for practitioners.

Key clinical message:
There is no consensus on an ideal treatment for feline demodicosis due to lack of published data in cats. This report provides support for sarolaner/selamectin spot-on treatment (Revolution Plus; Zoetis) as an effective, safe, and practical treatment for Demodex mange in cats.

Nasopharyngeal stenosis (NPS) is an important cause of chronic nasal discharge, stertor, and upper airway obstruction in dogs and cats. Treatment of NPS can be challenging and expensive and is associated with high recurrence and complication rates. Traditional treatment recommendations include balloon dilation of the stenotic tissue followed by placement of a covered, removable stent marketed for the treatment of NPS. However, these stents are costly, require technical expertise to place, and are available in limited sizes. This report describes a novel approach to treat NPS in 2 dogs using a piece of a silicone thoracic catheter cut to size for each dog as a removable stent. Both silicone stents were well tolerated and provided long-term resolution of clinical signs after removal. Major complications for 1 dog included movement of the stent rostrally with early restenosis after the suture securing the stent was accidentally pulled. Silicone thoracic catheters should be considered cost-effective options for the treatment of NPS in dogs.

Key clinical message:
This case report describes the successful use of a novel, removable silicone thoracic catheter to treat NPS in 2 dogs.

A 9-year-old neutered male German shepherd dog was presented because of a left pelvic-limb lameness and chronic draining tracts along the distomedial left stifle at 3 mo post-tibial plateau leveling osteotomy (TPLO) plate explantation. Tibial plateau leveling osteotomy was completed 9 mo before presentation. Bone imaging, surgical, and histopathologic evidence supported the development of a bone sequestrum at the surgical site. Culture and sensitivity assessment of the draining tracts indicated that the dog had developed a methicillin-resistant Staphylococcus pseudintermedius infection. The bone sequestrum was surgically debrided and vancomycin-impregnated calcium sulfate beads were packed into the resultant bony defect. At mid- and long-term follow-ups, the chronic infection and draining tracts had resolved. The dog recovered well with bony remodeling of the surgical site.

Key clinical message:
This case report describes the diagnosis and successful surgical management of an S. pseudintermedius-infected bone sequestrum at a TPLO site. Bone sequestrum and comprehensive antimicrobial management should be considered in the TPLO patient with chronically draining tracts post-implant removal. Increased awareness and appropriate treatment of bone sequestra and complicated infections can improve patient outcomes.

Splenic metastasis of hepatocellular carcinoma (HCC) is rare. An 11-year-old neutered male Maltese dog was presented for HCC recurrence surveillance. The dog had a history of transarterial chemoembolization and resection of HCC in the left medial liver lobe and papillary process of the caudate liver lobe. Computed tomography (CT) revealed a splenic mass with characteristics similar to those of the previous hepatic mass, including arterial tumor hypervascularity and heterogeneous enhancement in the portal venous and delayed venous phases. Splenic metastasis of HCC was confirmed via histopathological examination after splenectomy.

Key clinical message:
To our knowledge, this is the first report describing the CT findings of splenic metastasis of HCC in a dog. Splenic metastasis of HCC exhibited attenuation characteristics similar to those of the primary hepatic tumor in triple-phase CT. Therefore, comparing CT findings of previously diagnosed HCC to those of splenic masses may aid in diagnosing splenic metastasis of HCC.

A 9-month-old, intact male Siberian husky mixed-breed dog weighing 14.7 kg was referred because of right hind-limb lameness. A right femoral head ostectomy was performed. The dog was premedicated with intravenous (IV) dexmedetomidine and methadone. Anesthesia was induced with IV ketamine and propofol and maintained with isoflurane in oxygen delivered through a rebreathing circuit. Two hours after inhalant anesthesia was started, hyperthermia, hypercapnia, tachypnea, and tachycardia were observed. An acute malignant hyperthermia (MH) crisis was suspected. Isoflurane was discontinued and a propofol total IV anesthesia was started, minute ventilation was increased, active cooling was implemented, and IV dantrolene was administered. The dog remained stable overnight and was discharged on the following day. Six weeks later, the dog was anesthetized for femoral head ostectomy revision and to be neutered. A propofol total IV anesthesia protocol was implemented and O₂ was supplied using a T-piece breathing circuit connected to an O₂ tank. Anesthesia was unremarkable and the dog recovered uneventfully. In dogs, MH is a life-threatening emergency caused by an autosomal dominant mutation in the ryanodine receptor 1 gene. All dogs exposed to a triggering agent are at potential risk. An unexpected tachycardia and hypercapnia despite appropriate minute ventilation, as well as exclusion of other causes, should lead clinicians to suspect MH and initiate treatment. Discontinuing the triggering agent and administering dantrolene can help control the hypermetabolic reaction.

Key clinical message:
This report describes a case in which an acute MH crisis was suspected in a dog during inhalant anesthesia.

We describe the novel treatment of idiopathic atrial fibrillation (AF) and congestive heart failure (CHF) in a 10-year-old Nubian wether presented because of suspected hepatopathy. Physical examination findings, including irregularly irregular rhythm, tachycardia, bilateral jugular venous distention and pulsation, and ventral edema, raised concerns for primary cardiac disease. Findings of the echocardiogram, electrocardiogram, and ultrasound examinations supported the diagnosis of AF and CHF. Treatment was initially directed at rate control using β-blockers and fluid management (effusion and edema) using furosemide. Transcutaneous electrocardioversion (TCEC) was subsequently conducted under general anesthesia. Successful conversion to normal sinus rhythm was achieved with a single synchronized shock (1.25 J/kg = 100 joules). The wether remained in sinus rhythm with resolution of the CHF at a 2-month follow-up. This is the first report of successful treatment of AF and secondary CHF in a small ruminant using pharmacologic rate control, diuresis, and TCEC.

Key clinical message:
Management and successful treatment of AF and CHF is possible in small ruminants through intravenous heart rate control and TCEC. Treatment options for heart failure and cardiac disease are limited in ruminants. Further investigations to better understand the pharmacokinetics and dynamics of commonly used cardiac medications in ruminants are warranted.

Background
Surgical margin status can affect the risk for recurrence in dogs with cutaneous and subcutaneous masses. Histopathology is the current gold standard for margin assessment, despite evaluating small amounts of the surgical margin. Optical coherence tomography (OCT) has been described for surgical margin assessment following the excision of canine cutaneous and subcutaneous tumors.

Objective
To assess the rates of recurrence and metastasis following excision with an incomplete margin on OCT and confirmed with histopathology.

Animals and procedure
Seventy-one excised canine cutaneous and subcutaneous tumors underwent OCT imaging and histopathologic assessment.

Results
Of 61 tumors, 51 were malignant, including 21 soft tissue sarcomas and 21 mast cell tumors. Ten dogs experienced local tumor recurrence, with 7/10 and 8/10 having incomplete margins on OCT and histopathology, respectively. Ten dogs experienced distant metastasis, with 6/10 and 8/10 having incomplete margins on OCT and histopathology, respectively.

Conclusion and clinical relevance
Local recurrence occurred in tumors with predominately incomplete margins following advanced surgical margin assessment; however, not all tumors with incomplete margins developed local recurrence. Further prospective research is needed to assess the effect of entire surgical margin imaging on patient outcomes.

Background
Bovine foot rot (BFR) and bovine digital dermatitis (BDD) are infectious foot lesions with overlapping clinical features that complicate diagnosis.

Objective
Our objective was to differentiate BFR and BDD using quantitative and qualitative techniques. Populations of BFR- and BDD-associated bacteria were compared across sampling strategies, histopathological features described, and risk factors assessed via surveys.

Animals and procedure
Lame cattle were assessed and bacteria in punch biopsy samples (PB-samples), swabs, and subcutaneous samples (SC-samples) were quantified using quantitative real-time PCR. In addition, PB-samples were used for hematoxylin and eosin and Warthin-Faulkner staining. Feedlot records and producer surveys captured risk factors and producers’ opinions on management practices.

Results
Swabs and SC-samples had varying bacterial abundances compared to PB-samples. Histopathology and risk factors were not diagnostic for BFR versus BDD.

Conclusion and clinical relevance
Higher bacterial loads in swabs compared to PB-samples suggested careful consideration of their use as an alternative to punch biopsies in studying BFR and BDD. Furthermore, histology did not differentiate these diseases. Fusobacterium spp. population differences in dermis and SC-samples could indicate distinct, species-level roles in BFR pathogenesis. In addition, risk factors such as weight and lameness scores could not distinguish between BFR and BDD.

Objective
This study aimed to document antimicrobial resistance patterns of bacteria frequently isolated at a referral equine hospital between 2020 and 2022 and to compare these results to those of studies carried out in previous decades at the same reference center.

Procedure
Using the Kirby-Bauer method, 340 tests were completed on bacterial isolates and compared to 233, 255, and 396 tests carried out in 1986 to 1988, 1996 to 1998, and 2007 to 2013, respectively. Data were analyzed with X² tests for trends, followed by pairwise Fisher tests and Bonferroni corrections.

Results
Increasing resistance to at least 1 antibiotic was observed for 5 of the 6 bacteria studied, including increasing resistance to enrofloxacin for Escherichia coli, Pseudomonas spp., Enterobacter spp., and staphylococci, and to ceftiofur for Enterobacter spp. and staphylococci. Resistance of Actinobacillus spp. to ampicillin and penicillin decreased over time, whereas resistance of Streptococcus equi subsp. zooepidemicus to penicillin was not observed.

Conclusion and clinical relevance
Bacteria isolated from horses had increasing resistance to antibiotic classes considered critically important for human health. However, penicillin remained an appropriate 1st-line antibiotic for Actinobacillus spp. and Streptococcus equi subsp. zooepidemicus in our area.

Objective
A retrospective analysis was conducted using data from a large commercial sheep operation to determine if selection for larger litter sizes affected lamb birth weight, health, and performance.

Animals and procedure
Data on lamb health, performance, and carcass traits were collected during 2 vaccine trials conducted at a large commercial sheep operation. Data from each trial were analyzed for simple associations between ewe litter size, lamb birth weight, and lamb health, growth performance, and carcass traits.

Results
Increased litter size was associated with decreased lamb birth weight, and both were associated with higher mortality rates, including starvation and enteritis, and poorer growth performance and carcass traits.

Conclusion and clinical relevance
Increasing ewe prolificacy can reduce lamb birth weight, growth performance, and carcass traits and increase mortality losses. Veterinarians and sheep producers should consider the negative effects of selecting breeds with very large litter sizes when trying to optimize the production of lamb meat per ewe per year.

Objective
This study investigated the feasibility and effectiveness of blend electrolysis for hair removal in dogs.

Animals
We studied 3 healthy adult laboratory beagles.

Procedure
Small areas of palmar interdigital skin on the paws were treated with electrolysis using 6 procedures within 3 mo. The procedures were conducted under mild sedation and local anesthesia with lidocaine. Hair coat density was subjectively assessed by comparing pre-treatment dermoscopic images of the same areas.

Results
The average procedure time was 55 min. There were minimal complications. The procedures were well tolerated and resulted in either reduced hair density or complete alopecia. This effect persisted for at least 3 mo following the last treatment. One dog, examined 21 mo after treatment, exhibited a minimally distinguishable hypotrichotic area with slightly shorter and sparser hair.

Conclusion
Blend electrolysis is a feasible, though time-intensive, method for temporary hair removal in dogs.

Clinical relevance
Further research is required to investigate the efficacy and effort-to-result ratio of this method for permanent hair removal in dogs of different breeds and across different body areas.