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141.
A key element in the EU Common Agricultural Policy (CAP) will be a single farm payment system that is linked to compliance with rules on, for instance hygiene standards. However, there are no recommended methods for assessing the hygiene proficiency of pig production farms. The present study was undertaken to develop a method for this purpose. A first implementation was done on pilot scale; with a set of both conventional and organic pig farms (N = 15). Fifty hygiene-related factors were selected, especially with reference to the possible proliferation of enteric pathogens Listeria monocytogenes, Yersinia enterocolitica and Yersinia pseudotuberculosis. The factors were allocated into 8 evaluation categories: (1) general production management, (2) animal density, (3) the outdoor area for pigs, (4) pest and pet animals, (5) general hygiene in the piggery, (6) pen hygiene, (7) feed production hygiene, and (8) feeding hygiene. A farm questionnaire and a supplementary on-site observation form were devised, and one arbitrary scale of hygiene points assigned for each factor. In addition to the mailed questionnaires, one person subsequently visited all the farms, perused the questionnaire with the owners and completed the observation form. The hygiene scores of the farms in each evaluation category were compared both without weighting and with weighting based on expert opinions. The method proved to be feasible and applicable to different types of production.  相似文献   
142.
143.
In three Austrian rabbit units (two in the west, one in the east) heavy losses occurred in April/May 1989. The clinical course (deaths in adult animals, haemorrhagic diathesis) of the disease was indicative for an infection with the RHD-virus. Necropsy confirmed the suggestive clinical diagnosis as bleeding of the nostrils, hyperaemia in the respiratory tract, spleen tumor, partly decolorized livers, hyperaemia of kidneys with rare petechias could be observed. Histologic examination revealed centrolobular liver necrosis, lung bleeding and edema, tumor of spleen and atrophy of spleen follicles. Rabbits infected with organ suspensions died within 48 hours. The organ suspensions and the suspensions of the already necropsied animals showed a haemagglutination titer for above 1:100. This reaction could be inhibited with a specific RHD-antiserum. The intramuscular application of a RHD-reference strain in one hare, two wild rabbits and a rabbit did not induce clinical disease or death of the leporids during a six week observation period. The rabbit died within 48 hours post infection. However the hare and wild rabbits showed high antibody titers by ELISA at the end of the observation period. Before infection the two wild rabbits were serologically negative.  相似文献   
144.
Bilateral metacarpophalangeal radiographs of 100 Thoroughbreds were examined for visualization and location of the major nutrient foramen of the proximal phalanx. The foramina were located on the dorsal or palmar aspects of the cortex or were not visible radiographically. Of the 100 horses, 60 had the same pattern in both forefeet. In the remaining 40 horses, the left and right proximal phalangeal foramina were asymmetric. Of the 200 proximal phalangeal foramina (100 horses), 53 were on the dorsal aspect of the cortex and 101 were on the palmar aspect of the cortex; 46 were not visible radiographically. Significant effect of age or gender could not be determined.  相似文献   
145.
A yearling Arabian-type filly with a history of poor growth, erythrocytosis, hypoglycemia, and high liver enzyme activities was admitted to the hospital for evaluation. Three days after admission, the filly collapsed, deteriorated rapidly despite treatment, and was euthanatized. A metastatic hepatocellular carcinoma with capsular rupture and hemoperitoneum were found at necropsy. Primary liver tumors are rare in horses, and hepatocellular carcinoma has been reported in only 1 other horse. The systemic manifestations of the tumor in this filly included weakness, weight loss, inappetence, erythrocytosis with tumor production of erythropoietin, persistent hypoglycemia with normal serum insulin concentrations, serum alpha-fetoprotein (normally present only during fetal life), and terminal massive hemoperitoneum, all features of the syndrome in man.  相似文献   
146.
OBJECTIVE: To evaluate the use of arthroscopy as the primary method for removal of large patellar fracture fragments. DESIGN: Retrospective study. ANIMALS: 5 performance horses of various breeds with patellar fractures. PROCEDURE: Clinical signs of lameness, external evidence of injury, and radiography were used to diagnose and determine fracture orientation. Arthroscopy of the stifle joint was performed on the affected limb with the horse positioned in dorsal recumbency and under general anesthesia. Progress after surgery was determined by evaluating medical records and via telephone conversations with owners. RESULTS: 4 of 5 horses had fractures of the medial aspect of the patella and 1 horse had a fracture of the lateral aspect of the patella. There were no postoperative complications with the joint or the arthroscopic portal incisions. Recovery periods ranged from 3 to 5 months. All horses recovered completely from surgery, and performed at the same or higher level of competition as before arthroscopy. CONCLUSIONS AND CLINICAL RELEVANCE: Femoropatellar joint arthroscopy is a favorable means by which evaluation of the stifle joint and removal of large fracture fragments can be achieved with negligible postoperative complications.  相似文献   
147.
Superovulation of female rabbits was induced by subcutaneous injection(s) of porcine FSH. Zygotes were recovered 17 to 19 hr after hCG injection and were classified into two categories under a microscope equipped with Nomarski interference-contrast optics at x 200 magnification: (A) zygotes with clearly visible pronuclei, or (B) zygotes with visualized pronuclei after 10 min centrifugation at 12,000 x g. No significant difference between strains was found in the proportion of category-A zygotes (JW 72.6% vs NZW 79.3%). Pronuclei of category-A zygotes were located in the center of the cytoplasm, and the pronuclei of category-B zygotes were slightly moved by centrifugation toward the mass of cytoplasmic lipid droplets. Exogenous DNA solution (5 microg/ml of fusion gene composed of bovine alphaS1-casein promoter and human growth hormone structural gene) was microinjected into the pronucleus of the JW zygotes. The pronucleus of category-A zygotes with a mean volume of 7.4 pl swelled up to 16.6 pl (132% increase), while that of category-B zygotes with a mean volume of 6.1 pl swelled up to 15.9 pl (148% increase). Nevertheless, similar proportions of category-A and category-B zygotes developed into offspring after transfer to recipient females (11.1 and 11.2%, respectively). The efficiency to produce hGH-carrying transgenic rabbits was 0.9% (2/235) from category-A zygotes and 0.5% (1/215) from category-B zygotes (P>0.05). To date, transgenic rabbits have been produced without centrifugation of pronuclear zygotes. However approximately 25% of fertilized rabbit zygotes can be used for DNA microinjection after they have been centrifuged to visualize their pronuclei.  相似文献   
148.
1. Coir dust was evaluated as broiler litter in comparison with sawdust and rice husk using 135 commercial broilers. Forty-five broiler chicks were reared to 42 d on a 50 mm layer of each of these litters. 2. Birds reared on coir dust showed no difference in food consumption, body weight gain, food conversion efficiency production number and survivability in comparison to those reared on saw dust and rice husk. 3. It was concluded that coir dust is suitable as broiler litter when cheaply available.  相似文献   
149.
Knowledge of the frequency of direct and indirect contacts between pig herds is a requirement for understanding the potential between-herd transmission of pathogens. Our aim was to investigate the different contacts between Belgian pig herds. We obtained data by conducting a postal survey on 421 pig herds in August 2005 and by analysis of available information on livestock movements in the national identification-and-registration database (18-months period in 2004-2006). Direct contacts included transports of pigs by onto-farm, off-farm and between-farm movements. Indirect contacts included vehicles entering the herd and visitors entering the stables. The median number of direct contacts per herd made by onto-farm movements was 0.2/month (Q1: 0; Q3: 0.5). About 1.2% of herds had > or = 3 onto-farm movements/month. We used a zero-inflated negative-binomial regression model to describe differences in the number of onto-farm movements according to herd size and herd type. Piglet multipliers followed by finishing herds were predicted to have the most onto-farm movements. Farrow-to-finishing herds made less movements compared to breeding herds. A median of 3997 between-farm movements/month was made in Belgium; these mainly concerned piglets. The median number of origin herds during an 8-month period for between-farm movements was 4 (Q1: 2; Q3: 8). For a typical 1-month period, we constructed directed graphs of between-farm piglet and replacement stock movements, illustrating potential receivers and distributors of infection. Of these between-farm movements, many were made over a short distance (median straight-line distance 19 km (Q1: 8; Q3: 36)). The median number of vehicles entering a herd and visitors entering the stables was 8/month (Q1: 6; Q3: 13) and 3/month (Q1: 2; Q3: 6) respectively. The number of indirect contacts by vehicles and persons were associated with herd size (Spearman's r: 0.7 and 0.2), herd type and other factors. Skewness of both direct and indirect contacts, illustrated that there was a wide variety in contact structure between pig herds in Belgium. Infection control might benefit by accounting for this variation in contacts and by targeting 'high-risk' herds in case of animal-disease emergencies.  相似文献   
150.
Summary: The anatomy of the canine tail and its relationship to the physiological functions of the tail are described and the effect of tail docking on these is discussed. Current knowledge on the physiology and anatomy of pain is described with particular reference to cosmetic tail docking in the neonatal puppy. Recent advances in knowledge about pain and the changes in approach to pain management, refute the premise that 'puppies do not feel pain therefore tail docking is not inhumane' and also the premise that 'the pain and the effects of tail docking are insignificant.' Six criteria to test the 'necessity' to dock dogs are presented; this article shows that the reasons advanced for tail docking do not satisfy these criteria and so that docking dogs' tails cannot be justified.  相似文献   
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