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111.

Now that group housing is replacing individual crates, so that calves can lie, stand and walk on the pen floor, the quality of the floor for group-housed calves has become the focus of attention. The reaction of two groups of four calves to a double area of floor made from two materials (wooden slats and synthetic slats with a rubber coating) was examined round the clock for 5 days. The calves were switched between pens twice, and in each case the 5 day observation period was repeated. In all three phases all calves spent significantly more time ( P <0.01) lying on the wooden floor: on average 656 min day -1 compared with 294 min day -1 on the synthetic floor. The time spent in the standing/walking position on both floors, occurrence of slip incidents and self-maintenance behaviour did not differ significantly between floors. The observations on use of the pen floor for lying and for standing/walking in combination with feeding, plus observations on fouling of the floors with excreta suggest that future pen design could be functionally divided into lying and walking/eating areas.  相似文献   
112.
The goal of advanced life support in CPR must be to restore and maintain respiratory and hemodynamic effectiveness, and to correct the underlying dysrhythmia. Optimal basic life-support techniques must be continued to meet these goals. Many drugs have been suggested in the treatment of cardiac arrest, but unfortunately, drug effects are inconsistent and resuscitation rates remain low. Epinephrine, atropine, lidocaine, bretylium, and naloxone remain important drugs for consideration in CPR in most animals with cardiac arrest. The best chance of survival remains in early recognition of animals susceptible to arrest and in treatment of the underlying cause.  相似文献   
113.
Eight female pigs (26–61 kg) provided with a simple T-cannula about 10 cm proximal to the ileo-caecal valve, were used in two experiments to investigate the effects of Ca/P ratio, P level and supplementation with phytase (500 FTU/kg) on precaecal, post-ileal and total tract disappearances of organic matter (OM), phosphorus (P) and calcium (Ca). In experiment 1, two Ca/P ratios and two P levels were tested according to a 2 × 2 factorial arrangement within a Latin square design. In experiment 2, the diets of experiment 1 were supplemented with phytase (500 FTU/kg). There was a substantial absorption of OM, P and Ca in the post-ileal tract for all diets. Precaecal and total tract disappearances of OM were reduced by phytase addition (−4.4 and −0.8%, respectively). Supplementation with phytase resulted in an improvement of total tract and post-ileal P disappearances by 10.3 and 12.1%, respectively, without affecting precaecal P disappearance. Addition of feed phosphate resulted in a higher precaecal disappearance of P (+10.8%), resulting in a higher total tract disappearance of P (+5.9%). Addition of limestone had little effect on disappearances of OM, P and Ca, but reduced activity of supplemental phytase and had a negative influence on growth performance. Precaecal, post-ileal and total tract Ca disappearances were hardly affected by the examined dietary factors. The results might indicate that P from feed phosphate is absorbed primarily prececally and that P from phytate, liberated by microbial phytases, is dominantly absorbed post-illeally.  相似文献   
114.
Papillomaviruses (PVs) are highly species- and site-specific pathogens of stratified squamous epithelium. Although PV infections in the various Felidae are rarely reported, we identified productive infections in six cat species. PV-induced proliferative skin or mucous membrane lesions were confirmed by immunohistochemical screening for papillomavirus-specific capsid antigens. Seven monoclonal antibodies, each of which reacts with an immunodominant antigenic determinant of the bovine papillomavirus L1 gene product, revealed that feline PV capsid epitopes were conserved to various degrees. This battery of monoclonal antibodies established differential expression patterns among cutaneous and oral PVs of snow leopards and domestic cats, suggesting that they represent distinct viruses. Clinically, the lesions in all species and anatomic sites were locally extensive and frequently multiple. Histologically, the areas of epidermal hyperplasia were flat with a similarity to benign tumors induced by cutaneotropic, carcinogenic PVs in immunosuppressed human patients. Limited restriction endonuclease analyses of viral genomic DNA confirmed the variability among three viral genomes recovered from available frozen tissue. Because most previous PV isolates have been species specific, these studies suggest that at least eight different cat papillomaviruses infect the oral cavity (tentative designations: Asian lion, Panthera leo, P1PV; snow leopard, Panthera uncia, PuPV-1; bobcat, Felis rufus, FrPV; Florida panther, Felis concolor, FcPV; clouded leopard, Neofelis nebulosa, NnPV; and domestic cat, Felis domesticus, FdPV-2) or skin (domestic cat, F. domesticus, FdPV-1; and snow leopard, P. uncia, PuPV-2).  相似文献   
115.
Organisms in the genus Anaplasma are obligate intracellular pathogens that multiply in both vertebrate and invertebrate hosts. The type species, Anaplasma marginale, causes bovine anaplasmosis and infects erythrocytes of the vertebrate host and undergoes a complex developmental cycle in ticks which serve as biological vectors. Infected cattle, wild ruminants and ticks can all serve as reservoirs of A. marginale. In this study, hunter killed Iberian red deer (Cervus elaphus hispanicus) from the region of Castilla-La Mancha in southwestern Spain were tested for Anaplasma infection. We found that 10% of the deer examined were seropositive for Anaplasma. Three A. marginale strains were subsequently obtained from salivary glands of Hyalomma marginatum that were removed from these deer, and the sequence of the major surface protein (msp)4 gene was determined for each strain and used for phylogenetic studies. Maximum parsimony analyses of msp4 sequences from H. marginatum ticks in comparison with New World cattle and bison isolates reported previously, suggested different origins for these Spanish A. marginale strains. The results of this study demonstrated that Iberian red deer are naturally infected with Anaplasma, and may therefore serve as a wildlife reservoir of the pathogen. Although the link between deer infection and the strains of A. marginale identified in ticks was not established, H. marginatum and Rhipicephalus bursa were identified as potential biological vectors for A. marginale in this region and may effect transmission of A. marginale between deer and cattle populations.  相似文献   
116.
Effects of extracorporeal shock wave therapy on bone   总被引:6,自引:0,他引:6  
Extracorporeal shock waves have been used for 30 years to fragment uroliths for nonsurgical treatment for urolithiasis in humans. Applied to bone, shock waves delivered at the appropriate energy and pulse number, can stimulate osteogenesis. In Europe, shock waves are routinely used to treat nonunions in humans despite poor understanding of the mechanism of action. Shock wave therapy has also been used clinically in horses. Preliminary experimental studies indicate that shock wave therapy does not damage soft tissue in the distal aspect of the equine limb and can stimulate osteogenesis throughout the depth of the near cortex of the metacarpus and metatarsus.  相似文献   
117.
Effects of genetic variation in porcine adipocyte and heart fatty acid-binding protein genes, A-FABP and H-FABP, respectively, on intramuscular fat (IMF) content and backfat thickness (BFT) were examined in F2 crossbreds of Meishan and Western pigs. The involvement of each FABP gene in IMF accretion was studied to confirm previous results for Duroc pigs. The F2 crossbred pigs were genotyped for various markers including microsatellite sequences situated within both FABP genes. Linkage analysis assigned the A-FABP and H-FABP genes to marker intervals S0001-S0217 (20 cM) on SSC4 and Sw316-S0003 (16.6 cM) on SSC6, respectively, refining previous chromosomal assignments. Next, the role of both chromosome regions/genes on genetic variation in IMF content and BFT was studied by 1) screening SSC4 and SSC6 for QTL affecting both traits by performing a line-cross analysis and 2) estimation of the effect of individual A-FABP and H-FABP alleles on both traits. In the first analysis, suggestive and chromosome-wise significant evidence for a QTL affecting IMF was detected on SSC6. The H-FABP gene is a candidate gene for this effect because it resides within the large region containing this putative QTL. The second analysis showed a considerable but nonsignificant effect of H-FABP microsatellite alleles on IMF content. Suggestive evidence for a QTL affecting BFT was found on SSC6, but H-FABP was excluded as a candidate gene. In conclusion, present and previous results support involvement of H-FABP gene polymorphisms in IMF accretion independently from BFT in pigs. Therefore, implementation of these polymorphisms in marker-assisted selection to control IMF content independently from BFT may be considered. In contrast to previous findings for Duroc pigs, no evidence was found for an effect of the A-FABP gene on IMF or BFT in this population.  相似文献   
118.
Six Belgian Blue bulls (double-muscled type) and six Friesian bulls were offered a fattening diet for 34 weeks. Plasma samples were obtained once a week and also every 20 min over a 24 h period, 7 weeks before slaughter.No differences were observed between the breeds in plasma glucose, urea and free amino nitrogen concentrations, while creatinine was significantly higher in the Belgian Blue bulls. Tri-iodothyronin, tetra-iodothyronin, insulin-like growth factor 1, insulin and testosterone concentrations were higher in the Holstein group. In contrast, the Belgian Blue bulls appeared to produce more growth hormone. The slaughter weight, carcass weight, dressing percentage and proportion of lean meat were significantly higher in the Belgian Blue group. The characteristics of muscle mass (carcass weight, dressing percentage and proportion of lean meat) were positively correlated with creatinine and with the total peak area or peak amplitude of growth hormone. The insulin concentration was positively correlated with the proportion of adipose tissue in the carcass and negatively correlated with the proportion of muscle. There were no correlations between the carcass characteristics and insulin-like growth factor 1 or testosterone. No further information was provided when the ratios of the hormones were correlated with carcass characteristics.  相似文献   
119.
The morning after participating in a dog show, a 2-year-old Pomeranian dog was found dead in a pool of bloody feces. Necropsy revealed hemorrhagic gastroenteritis of the entire gastrointestinal tract, with many Gram-positive bacilli on the surface and in the lumen and crypts of the intestine. Enterotoxin-positive type A Clostridium perfringens were isolated in large numbers. This dramatic case of fatal C. perfringens gastroenteritis highlights the need to better understand the role of this bacterium in enteric disease of dogs.  相似文献   
120.
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