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991.
Objective: To describe a technique used for reduction and internal fixation of sacral fractures in cattle. Study Design: Case series. Animals: Three heifers aged 19–32 months with deformation of the tail head and tail paralysis attributable to a closed fracture of S5 or S4 and S5. Methods: Fractures were reduced and repaired under general anesthesia. A narrow, 6–10‐hole, locking compression plate (LCP) was placed on the spinous processes of S5 and the first coccygeal (Co1) using 5.0 mm locking head screws. Follow‐up inquiries were made by telephone (3/3), and cows were examined clinically and radiographically 2 (1 cow) to 9 (1cow) months postoperatively. Results: No complications were encountered. The range of movement of the tail improved so that soiling of the tail during defecation was no longer a problem. In all heifers, the normal top line was restored and there was no narrowing of the pelvic canal. Unassisted calving occurred in all heifers, and follow‐up radiographs for 2 cows showed complete fracture healing. Conclusion: LCP‐osteosynthesis of the spinous processes provided sufficient stability for internal fixation of sacral fractures. Marked improvement in tail function occurred postoperatively without decompression by laminectomy.  相似文献   
992.
The alpaca is the most important fiber producer of the South American camelid species, and is an important source of income for the Andean communities. Nowadays, fiber diameter is considered the main selection objective in alpaca populations throughout the world. However, fiber diameter increases with the age of the animals, and it would be preferable to select those animals that maintain a thin fiber throughout their life span. The goal of this study was to describe the genetic relationship between fiber diameter at weaning age (6 mo) and the evolution of fiber diameter along the life span. The analysis of the evolution of fiber diameter was studied as a useful model for canalization and as a longitudinal trait by hierarchical Bayesian analysis. The results suggested that substantial genetic variation exists for fiber diameter and also for the variability and linear growth of the fiber diameter. Thus, a genetic selection program is plausible to modify the evolution of fiber diameter with time, together with a favorable correlated decrease in fiber diameter.  相似文献   
993.
OVERVIEW: Mycobacterium microti infection is infrequently described in cats in the veterinary literature. It can be one of a large number of possible differential diagnoses in a feline patient with dermal nodules and non-healing draining ulcers, and can occasionally spread to involve the lungs and/or other areas of the body. CASE SUMMARY: This report describes the clinical signs, eventual diagnosis and variable response to treatment in a cat in Switzerland with recurrent cutaneous M microti infection. Only after several diagnostic and therapeutic attempts, over more than 2 years, was the species of Mycobacterium finally identified and targeted therapy given. PRACTICAL RELEVANCE: For any cat in which there is even a low suspicion of mycobacterial infection, the authors recommend that an aggressive diagnostic approach is taken. Tissue specimens should be collected and frozen early on, and, as soon as acid-fast bacilli are detected, samples should be sent to a mycobacterial reference laboratory for definitive identification. LITERATURE REVIEW: A review of the literature relating to the aetiopathogenesis, diagnosis and management of M microti infection in cats and dogs is included. This is supplemented with clinical and therapeutic experience gained from this case and other, unpublished cases managed over the past 15 years by one of the authors (DGM).  相似文献   
994.
Hip dysplasia is a common orthopaedic developmental disorder of dogs. This paper reviews the treatment options available for management of the condition in the skeletally immature and adult dog.  相似文献   
995.
The current cervical artificial insemination (CAI) procedure, involving deposition of excessive sperm numbers, is uneconomical for pig industry. The most obvious alternative requires uterine deposition in combination with fixed-time AI, which would reduce the number of sperm required per pregnant sow, thus allowing the best use of valuable boars and, ultimately, the commercial integration of frozen-thawed and sexed sperm. This review depicts possible best ways to implement an efficient use of liquid-stored, frozen-thawed and sexed sperm by the pig industry.  相似文献   
996.
1. A physiologically-based pharmacokinetic model was developed for the purpose of describing the relationship between plasma concentration of drugs and their deposition into eggs. 2. By incorporating the physiology of egg formation into the model, the transfer of drugs into the egg albumen and yolk could be described using rate constants. 3. The model was used to describe concentrations in albumen and yolk of sulphanilamide, sulphaquinoxaline and pyrimethamine as a function of time using datasets from the literature. 4. The model could be used as a tool to obtain an insight into those properties of a drug which are responsible for the amount of residue in eggs, and could help in the design of critical studies for determining withdrawal periods for eggs.  相似文献   
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999.
Grazing management is important for sustaining the productivity and health of rangelands. However, the effects of grazing management on herbage growth and species composition in the tropical savannas of northern Australia are not well known. In this eight-year study the influences of utilization rate and resting pastures from grazing on vegetation dynamics were measured at three sites in northeast Queensland, Australia. The sites had high, medium, and low soil fertility, and there were two land condition classes (States I and II) at each site. Severe drought occurred during the first four years, but above-average rainfall was received in the second half of the study. High utilization rates reduced biomass, perennial grass basal area, and ground cover. The reduction in biomass was due to both higher consumption and decreased primary production. State I condition plots at the high and medium soil fertility sites were initially dominated by decreaser perennial grasses, but these declined at all utilization levels, particularly the high rate. They were largely replaced by exotic perennial grasses. At the low fertility site there were no exotic grasses, and the decreaser grasses increased in all treatments, with the increases greatest in plots with low utilization or medium utilization plus resting. In the State II condition plots at the high and medium fertility sites, low or moderate utilization, led to an increase in both decreaser and exotic perennial grasses; with high utilization the decreaser perennial grasses declined and were replaced largely by exotic perennial grasses. This study clearly demonstrated that either conservative stocking with year-round grazing or a grazing system that includes some wet-season resting will help maintain land in a desirable state or help facilitate the transition from a less desirable ecological state to one more desirable for pastoral production and rangeland condition.  相似文献   
1000.
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