Muscle strain injuries of the hindlimb in eight horses: diagnostic imaging,management and outcomes

Objective To describe the clinical presentation, ultrasound findings, management and outcome in horses with muscle tear injuries of the hindlimbs. Design Retrospective case series Procedure Medical records of eight horses were reviewed and information on signalment, history, presenting complaint, physical examination findings and further diagnostic tests were recorded. Diagnosis of muscle injury was determined by the presence of abnormal ultrasound findings, compared with the contralateral limb, and, when required, nuclear scintigraphy. Follow-up information was obtained via telephone interviews with owners, trainers and referring veterinarians. Results Muscle tears causing lameness were identified in the middle gluteal (3), semitendinosus (1), semimembranosus (2) and gracilis (2) muscles. Tears were classified by ultrasound imaging as partial (6) or complete (2). The degree of lameness did not appear to be indicative of the extent of injury or of completion of healing. Long-term follow-up was available for seven horses and the outcome was favourable in six cases. Conclusions and clinical relevance Ultrasonography is useful in the diagnosis and assessment of moderate to severe muscle strain injuries. The prognosis appears to be favourable in most cases, although recurrence of injury and lameness can delay the return to athletic activity and an inferior outcome with persistent gait abnormality may occur.     

A Histological Evaluation of Rabbit Tendons Sutured Using the Bunnell Pattern

Development of ischemia in healing tendons was assessed in 18 rabbits. One superficial digital flexor tendon in each rabbit was incised and anastomosed using a Bunnell pattern. The repair site was enclosed in a porous, woven Dacron tube before skin closure. The limb was immobilized with a cast. Rabbits were euthanized 1, 4, and 8 weeks after surgery, and tendons were harvested and examined microscopically. Regions of the tendon included in the suture pattern were ischemic and acellular at 1 week, while adjacent areas still containing patent vessels remained viable. Within 4 weeks, a well vascularized neotendon with collagen bundles organized parallel to the long axis of the tendon developed along the periphery and between the opposed tendon ends. After 8 weeks, the ischemic regions of the tendon had not revascularized or become integrated with the neotendon. Adjacent collagen bundles not originally included in the Bunnell pattern were integrated with neotendon collagen fibers.     

Duration of immunity in salmonids vaccinated by direct immersion with Yersinia ruckeri and Vibrio anguillarum bacterins

Abstract. The level of protective immunity was determined for several salmonid species following vaccination by the direct immersion method with commercial Vibrio anguillarum (two serotypes) and Yersinia ruckeri (Hagerman strain) bacterins. The duration of protective immunity varied with the bacterin concentration, size and species of fish, but the duration between the two bacterins was comparable. In fish under 1 g duration of protective immunity was longest when the most concentrated bacterin was used. Generally, immunity lasted in 1-g fish for about 120 days, in 2-g fish for about 180 days, but in 4-g fish and larger immunity lasted for a year or longer. Coho salmon ( Oncorhynchus kisutch ) and sockeye salmon ( O. nerka ) retained immunity for a longer time and pink salmon ( O. gorbuscha ) the shortest time. Chinook salmon ( O. tshawytscha ) and rainbow trout ( Salmo gairdneri ) were intermediate. Field data generally followed the laboratory tests, but the duration appeared somewhat shortened. In one test 20-g rainbow trout were vaccinated by the shower method and no loss of immunity occurred after 311 days.     

Intestinal ganglioneuroma in a kitten–a case report and review of literature

An intestinal ganglioneuroma of a 6–week–old male kitten is described. The neoplasm was well circumscribed and involved a 6–5–cm segment of the jejunum, which was dilated and had a 6–10 mm thick wall. It was characterized histologically by irregularly–arranged bundles of nerve fibres, with Schwann cells and single or groups of round or angular ganglion cells. Some of the ganglion cells had satellite cells. Vessels with prominent endothelial cells, and islands of epithelial cells forming acini, were also seen. The age of the kitten and slow nature of growth of this tumour led the authors to believe that this is a case of congenital neoplasia. This is the first report of an intestinal ganglioneuroma in a cat.     

Pharmacokinetics of florfenicol following intravenous and intramuscular doses to cattle

The disposition of florfenicol after single intravenous and intramuscular doses of 20 mg of florfenicol/kg of body weight (b.w.) to feeder calves was investigated. Serum florfenicol concentrations were determined by a sensitive high performance liquid chromatographic method with a limit of quantitation of 0.025 μg/ml. The extent of serum protein binding of florfenicol was only 13.2% at a serum florfenicol concentration of 3.0 μg/ml. Serum concentration-time data after intravenous administration were best described by a triexponential equation. Total body clearance and steady state volume of distribution were 3.75 ml/min/kg b.w. and 761 ml/kg b.w., respectively. The terminal half-life after intravenous administration was 159 min. The absolute systemic availability after intramuscular administration was 78.5% (range: 59.3–106%) and the harmonic mean of the terminal half-life was 1098 minutes, indicating slow release of the florfenicol from the formulation at the intramuscular injection site.