Comparative studies of BHV-1 variants by in vivo--in vitro tests.

The new encephalitogenic BHV-1.3 and previously characterized BHV-1 strains were studied with reference to their immunogenic and protective potency and their antigenic relationships using "in vitro" and "in vivo" tests. The "in vitro" results obtained by neutralization kinetics showed that the Los Angeles (LA) strain (BHV-1.1) and a vaginal isolate L-114 strain (BHV-1.2) had antigenic similarities. Conversely, the behavior of the encephalitogenic strain A-663 (BHV-1.3), was significantly distinct. The "in vivo" protection test was carried out in calves using LA and A-663 strains. Post-vaccination antibodies and challenge with A-663 strain showed that the immunogenic behavior and protective capacities of both strains were similar. Neutralization kinetics differences between BHV-1.1 and BHV-1.3 did not alter the "in vivo" protection against BHV-1.3 challenge.     

Open Intestinal Anastomosis with Surgical Stapling Equipment in 24 Dogs and Cats

Surgical stapling equipment was used to perform open antiperistaltic side-to-side ("functional end-to-end") entero-anastomoses in 20 dogs and 4 cats. Twenty-one anastomoses healed uneventfully. Seven animals with severe bacterial peritonitis required open peritoneal drainage and delayed abdominal closure. There was postoperative leakage at the anastomotic site in two dogs and a localized abscess at the staple line in one cat. No long-term complications occurred in follow-up periods of 3 to 29 months.     

Dynamic properties of molecularly thin liquid films

An experimental technique is described for simultaneously measuring the static and dynamic interactions of very thin liquid films between two surfaces as they are moved normally or laterally relative to each other. Film thickness can be measured and controlled to 1 angstrom. Initial results are presented of the transition in the physical properties of liquid films only one molecular layer thick to thicker films whose properties are practically indistinguishable from the bulk. In particular, the results show that two molecularly smooth surfaces, when close together in simple liquids, slide (shear) past each other while separated by a discrete number of molecular layers, and that the frictional force is "quantized" with the number of layers.     

Les différentes bandes de contention utilisées pour la confection de prothèses externes chez les petits animaux

The various orthopedic casting tapes used for external fracture fixation in small animals.     

Retrospective evaluation of xylazine/halothane anesthesia in 125 cattle

A retrospective morbidity and mortality study was carried out on 125 case records of cattle involving xylazine/halothane anesthesia at the Ontario Veterinary College, Guelph between May 1979 and February 1983.     

Sources of variation and prospects for improvement of productive efficiency in the dairy cow: a review

In this review, "productive efficiency" in dairy cows is defined as the yield of milk obtained in ratio to the nutritional costs associated with maintenance, milk synthesis and loss of body condition during lactation. Improvements in efficiency could occur as a result of changes in digestion and nutrient absorption, maintenance requirement, utilization of metabolizable energy for production or nutrient partitioning. Digestibility can be greatly enhanced by appropriate dietary manipulation. Likewise, it may be possible to reduce maintenance requirements and improve the efficiency with which metabolizable energy is used for milk synthesis by manipulation of the pattern of nutrients presented to tissues. However, these factors apparently do not respond to selection for increased milk yield, and little variation is observed among cows. In contrast, individual cows differ substantially in feed intake and in the partitioning of nutrients among body tissues. Techniques associated with genetic engineering and the early prediction of genetic merit have the potential to improve productive efficiency by manipulation of these processes. However, changes in nutrient partitioning and feed intake during lactation are coordinated by a complex network of controls that accommodate the nutrient requirements of each tissue while maintaining homeostatic balance. Future improvements in productive efficiency will therefore depend on our ability to understand the manner in which these controls operate.