Surgical Management of Fractures and Tendons.

Long bone fractures and disorders of tendons and ligaments represent a significant proportion of surgical orthopedic cases presented to ruminant veterinarians. The presentation of these patients, their diagnostic work-up, surgical treatment, and expected outcome will be discussed. The outcome of these cases depends largely on the presenting problem; however, accurate diagnosis and prompt surgical intervention can greatly improve the outcome of many of these cases.

Indications for and factors relating to outcome after rumenotomy or rumenostomy in cattle: 95 cases (1999-2011).

OBJECTIVE: To evaluate indications for and factors relating to outcome after rumenotomy or rumenostomy in cattle. DESIGN: Retrospective case series. ANIMALS: 95 cattle that underwent rumenotomy or rumenostomy. PROCEDURES: Medical records for 95 cattle that underwent either rumenostomy or rumenotomy at 2 veterinary teaching hospitals in 1999 through 2011 were analyzed. Reasons for the procedures were noted. Long-term outcome was determined during telephone interviews with owners. RESULTS: 42 (44%) bovids underwent rumenostomy and 53 (56%) bovids underwent rumenotomy. Among the 42 animals undergoing rumenostomy, 18 (43%) had rumen cannulas placed during elective procedures. Other indications for rumenostomy included ruminal tympany (bloat [n = 20]), esophageal obstruction (choke [1]), grain overload (1), and provision of access for administration of enteral nutrition (2). Indications for rumenotomy included traumatic reticuloperitonitis (n = 31), bloat (9), foreign body (6), choke (5), and other (2). Long-term follow-up data were available for 31 of 42 (74%) bovids that underwent rumenostomy. Of those 31 animals, 17 (55%) were still in the herd, 4 (13%) had been culled, and 10 (32%) had died or were euthanized. Long-term follow-up data were available for 38 of 53 (72%) bovids that underwent rumenotomy. Of those 38 animals, 13 (34%) were still in the herd, 14 (37%) had been culled, and 11 (29%) had died or been euthanized. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that rumenotomy and rumenostomy can be effective in treating or relieving complications secondary to forestomach disorders in cattle. Bovids undergoing rumen surgery had a favorable prognosis for survival and a fair prognosis for potential return to production.

Absorption and disposition of florfenicol after intravenous, intramuscular and subcutaneous dosing in alpacas.

The objectives of this study were to define disposition and systemic availability of florfenicol in alpacas. Administration of 20 mg/kg doses to 8 male alpacas by i.v., i.m. and s.c. routes was performed by randomized, 3-way crossover design. Clearance and steady state volumes (Vdss) after i.v. injection were 5 ml/min/kg and 775 ml/kg respectively. Mean residence time (MRT) and terminal phase half-life (T1/2λz) were 2.8 h and 2 h respectively. Maximum serum concentrations (Cmax) after i.m. were higher than s.c. administration (p = 0.034). After s.c. dosing, T1/2λz and MRT were greater than after i.m. injection (p < 0.001; p = 0.006 respectively). Mean absorption time (MAT) after s.c. dosing was also prolonged (p = 0.006). Fractional absorption of florfenicol after i.m. and s.c. was not different (p > 0.05). Serum florfenicol concentrations remained >1.0 µg/ml for 20 h after i.m. dosing. Differences in rate and extent of florfenicol absorption after extravascular dosing could influence therapeutic outcomes.

Stifle disorders: cranial cruciate ligament, meniscus, upward fixation of the patella.

Stifle injury in cattle can be a debilitating condition. Stifle injuries often present as nonspecific lameness with subtle clinical signs. Physical examination with manipulation of the stifle joint, radiographs, and analysis of the joint fluid can help to make a diagnosis. Cranial cruciate and collateral ligament injuries are among the most common traumatic injuries of the stifle joint. Although the prognosis is guarded, better success and less degenerative change are expected with early diagnosis and treatment. Meniscal injuries and upward fixation of the patella are less commonly diagnosed, but their clinical signs, treatment, and prognosis are discussed in this article.

Pharmacokinetics of florfenicol after intravenous and intramuscular dosing in llamas.

Florfenicol, is a broad spectrum antimicrobial agent with wide tissue distribution commonly used to treat camelids. To address the lack of drug disposition data for florfenicol in llamas, we evaluated the pharmacokinetics after 20mg/kg intravenous (i.v.) and intramuscular (i.m.) dosing. Serum concentrations were determined using a HPLC-UV assay and pharmacokinetic analysis was conducted using non-compartmental analysis. Following i.v. injection, systemic clearance and Vdss in llamas were 4.6 mL/min/kg and 737 mL/kg, respectively. Mean residence time after i.v. dosing was 3h. After i.m. injection, florfenicol was rapidly absorbed, with Cmax concentrations being 3.2 µg/mL at 0.5h, mean residence time was 15 h, mean absorption time was 12h and absolute bioavailability of florfenicol after i.m. injection was 63%. The prolonged absorption of florfenicol after i.m. administration suggests the apparent HL_λz reflects the absorption process rather than elimination of the drug. Florfenicol administration was not associated with adverse reactions after dosing by either route. Serum florfenicol concentrations remained >1.0 µg/mL for 12h after i.m. administration. For susceptible pathogens, once daily dosing of 20mg/kg body weight appears appropriate.

Arthroscopic approach and intraarticular anatomy of the stifle in South American camelids.

OBJECTIVE: To describe a cranial arthroscopic approach to the stifle of South American camelids and to report our clinical experience with camelid stifle arthroscopy. STUDY DESIGN: Experimental study and retrospective case series. ANIMALS: (1) Cadaveric alpaca hindlimbs (n = 18; 9 alpacas); (2) 1 alpaca and 1 llama METHODS: Polymethylmethacrylate joint casts (n = 2) were made to define stifle joint dimensions. Cadaveric stifle joints (n = 16) were evaluated arthroscopically to determine arthroscopic portal locations, describe the intraarticular anatomy, and report potential complications. An alpaca and a llama with stifle joint disease had diagnostic arthroscopy. RESULTS: Successful entry into the stifle joint was achieved in 16 cadaver limbs. Observed structures were: the suprapatellar pouch, articular surface of the patella, femoral trochlear ridges and groove, cranial aspect of the femoral condyles (n = 16); distal aspect of the cranial and proximal aspect of the caudal cruciate ligaments (14); and cranial aspects of the medial and lateral menisci (11), and cranial meniscotibial and intermeniscal ligaments (8). Stifle arthroscopy allowed for joint evaluation and removal of osteochondral fragments in 1 alpaca and 1 llama with naturally occurring stifle disease. Complications of cadaver or live procedures included minor cartilage scoring (3 stifles) and subcutaneous periarticular fluid accumulation (8 stifles). CONCLUSIONS: Arthroscopy provides a safe approach for diagnosis and treatment of stifle lesions in South American camelids.

Mast cell tumors in a llama (Lama glama).

A 9-year-old female llama (Lama glama) that served as a blood donor at The Ohio State University Veterinary Teaching Hospital developed multiple small, raised, firm, non-haired cutaneous masses on the right hip, left cheek, and right and left shoulders. Cytological evaluation of fine-needle aspirates from the cutaneous mass from the left shoulder and right hip comprised many well-differentiated, highly granulated mast cells with moderate numbers of eosinophils. Occasional mast cells exhibited erythrophagocytosis and contained a small amount of hemosiderin or several variably sized vacuoles. A cytologic diagnosis of mast cell tumor with evidence of prior hemorrhage was made, and the masses were surgically removed. Microscopically, each mass consisted of sheets of neoplastic round cells that formed nonencapsulated nodules in the dermis and infiltrated into the adjacent dermal collagen. Eosinophils were scattered among the mast cells at the periphery of the nodules. Neoplastic mast cells, but not eosinophils, exhibited positive membrane KIT expression and cytoplasmic vimentin staining. A final diagnosis of mast cell tumor was made based on cytology, histology, and immunohistochemistry.