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21.
Sows of differing parities and genetics were used at different locations to determine the effects of feeding added L-carnitine during lactation on sow and litter performance. In Exp. 1, sows (n = 50 PIC C15) were fed a lactation diet (1.0% total lysine, .9% Ca, and .8% P) with or without 50 ppm of added L-carnitine from d 108 of gestation until weaning (d 21). No differences in litter weaning weight, survivability, sow ADFI, or sow weight and last rib fat depth change were observed. Number of pigs born alive in the subsequent farrowing were not different (P>.10). In Exp. 2, parity-three and -four sows (n = 115 Large White cross) were used to determine the effect of feeding 0, 50, 100, or 200 ppm of added L-carnitine during lactation (diet containing .9% total lysine, 1.0% Ca, and .8% P) on sow and litter performance. No improvements in the number of pigs or litter weights at weaning were observed (P>.10). Sows fed added L-carnitine had increased weight loss (linear; P<.04), but no differences (P>.10) were observed in last rib fat depth change or subsequent reproductive performance. In Exp. 3, first-parity sows (n = 107 PIC C15) were fed a diet with or without 50 ppm of added L-carnitine during lactation (diet containing 1.0% total lysine). Sows fed added L-carnitine tended (P<.10) to have fewer stillborn and mummified pigs than controls (.42 vs .81 pigs). No differences were observed for litter weaning weight, survivability, or subsequent farrowing performance. Feeding 50 to 200 ppm of added L-carnitine during lactation had little effect on sow and litter performance.  相似文献   
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Tularemia in range sheep is an occasional cause of severe economic loss from mortality and unthriftiness as well as a hazard to persons in contact with the animals. Epizootics are unpredictable and explosive, therefore, prophylaxis is more practical than therapy. Live vaccine of proven value in man and in beavers was inoculated into mature ewes and elicited antibodies without harm to the sheep. However, challenge of immunity was not possible because virulent Francisella tularensis in large doses did not cause significant mortality in healthy, well managed, unimmunized sheep. Evidence suggests that a complex of stresses such as inclement weather, lambing and concomitant ectoparasitism render sheep more susceptible to tularemia.  相似文献   
25.
A series of in vitro studies was conducted to determine the effects of adding a commercial enzyme product on the hydrolysis and fermentation of cellulose, xylan, and a mixture (1:1 wt/wt) of both. The enzyme product (Liquicell 2500, Specialty Enzymes and Biochemicals, Fresno, CA) was derived from Trichoderma reesei and contained mainly xylanase and cellulase activities. Addition of enzyme (0.5, 2.55 and 5.1 microL/g of DM) in the absence of ruminal fluid increased (P < 0.001) the release of reducing sugars from xylan and the mixture after 20 h of incubation at 20 degrees C. Incubations with ruminal fluid showed that enzyme (0.5 and 2.55 microL/g of DM) increased (P < 0.05) the initial (up to 6 h) xylanase, endoglucanase, and beta-D-glucosidase activities in the liquid fraction by an average of 85%. Xylanase and endoglucanase activities in the solid fraction also were increased (P < 0.05) by enzyme addition, indicating an increase in fibrolytic activity due to ruminal microbes. Gas production over 96 h of incubation was determined using a gas pressure measurement technique. Incremental levels of enzyme increased (P < 0.05) the rate of gas production of all substrates, suggesting that fermentation of cellulose and xylan was enzyme-limited. However, adding the enzyme at levels higher than 2.55 microL/g of DM failed to further increase the rate of gas production, indicating that the maximal level of stimulation was already achieved at lower enzyme concentrations. It was concluded that enzymes enhanced the fermentation of cellulose and xylan by a combination of pre- and postincubation effects (i.e., an increase in the release of reducing sugars during the pretreatment phase and an increase in the hydrolytic activity of the liquid and solid fractions of the ruminal fluid), which was reflected in a higher rate of fermentation.  相似文献   
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Between 1977 and 1992, 15 adult dogs were presented to the Universities of Bristol, Glasgow, Liverpool and London with fractures of the radial carpal bone which had occurred without a known episode of violent trauma. Eleven of the dogs were boxers and the other breeds affected were a Pharaoh hound, rottweiler, springer spaniel and a greyhound. The condition was bilateral in three cases. Eleven dogs were treated surgically by cast immobilisation (four cases), fragment removal (one case), lag screw fixation (three cases), pan-carpal arthrodesis (one case) and lag screw reduction followed by pan-carpal arthrodesis (two cases). The remaining four dogs were treated conservatively with rest and tactical use of non-steroidal anti-inflammatory drugs. Follow-up periods ranged from two months to 11 years. Varying degrees of lameness, which tended to be exacerbated by exercise, persisted in all cases. The radial carpal bone appears to have at least three separate centres of ossification which eventually fuse; their planes of fusion correspond approximately to the two main fracture lines. These areas of fusion could be weak points within the radial carpal bone.  相似文献   
27.
Seventeen cats with injuries involving the distal tibia, talocrural joints, tarsus and metatarsus were treated with contoured connecting bar transhock external fixators as either primary or secondary fixation. The assemblies stabilised all the injuries successfully. Fracture union was achieved in 11 out of 12 cases. Excellent results were achieved in eight cats and the outcome was satisfactory in a further five. Those cats with injuries involving talocrural joint luxation with displacement and significant periarticular soft tissue disruption had poorer long-term results. Complications occurred in seven cases.  相似文献   
28.
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   
29.
Abstract. The effect of drought between summer 1995 and 1997 on stream and river nitrate concentrations was investigated using sites close to the long-running meteorological station in Oxford, UK. Nitrate concentrations in the River Windrush were relatively low during the drought, but after it had ended reached the highest level since records began in 1973. The low concentrations during the drought probably reflect a reduced contribution from agricultural runoff. High nitrate concentrations were found in a field drain at Wytham Environmental Change Network site during and after the drought, but discharge was greatly reduced. A woodland stream at Wytham had much lower nitrate concentrations than the field drain but these similarly increased during and after the drought. There was evidence that both a concentrating effect of low water volumes and enhanced soil nitrogen mineralization and nitrification rates were causing concentrations to rise. The effects of mineralization and nitrification were more important in woodland than agricultural land. Nitrate load over the course of a year was determined largely by discharge, but steeper gradients for the relationship between cumulative load and cumulative discharge were seen during and after the drought than before, reflecting the higher concentrations.  相似文献   
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