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Fourteen racing huskies were matched into pairs then assigned to two diets, a commercial stress diet and an experimental diet. Proportions of protein: fat:carbohydrate on an available energy basis were 23:57:20 in a commercial stress diet and 28:69:3 in an experimental diet. The team participated in the 1979 Iditarod Trail race and was overtaken by an episode of diarrhea. Clinical signs were suggestive of parvovirus infection; high serum titers of parvo antibodies were found after the race. Blood examination showed normal levels of metabolites, electrolytes and enzymes after the race. Erythrocyte counts were depressed significantly during the race, by 15% in dogs fed an experimental diet and by 27% in those fed a commercial stress diet. Erythrocyte parameters have also become depressed during the racing season in middle distance sled dogs fed 28% protein (energy basis) but not 32 or 39%. Depressed red blood cell production has been demonstrated previously in dogs subjected to stress induced experimentally in several ways, and its restoration has been affected by dietary protein. Erythrocyte parameters may be useful indicies of the degree of stress in a dog as well as the adequacy of its protein intake during stress.  相似文献   
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The main objective of the present work was to study the effect of cryopreservation of European eel sperm both on the sperm viability and the spermatozoa head morphology. Spermatozoa morphology was evaluated with computer-assisted morphology analysis after collection in fresh samples, after adding the freezing medium containing dimethyl sulfoxide as cryoprotectant and, finally, after the cryopreservation process and thawing. Cell viability was assessed, in both fresh and thawed samples, by Hoechst 33258 staining. Computer-assisted sperm analysis (CASA) was used to determine the percentage of motile cells and to measure motility parameters in sperm samples. A significant decrease of head perimeter (12.56%) and area (17.90%) was detected from spermatozoa in fresh to thawed samples, indicating that cells do not recover the original size after the cryopreservation process. CASA was used to measure the percentage of motile cells (51.9%) and spermatozoa motility parameters such as curvilinear, straight line and angular path velocities, as well as beating cross frequency. This technique was employed in the fresh sperm samples but proteins present at the freezing medium (L-alpha-phosphatidylcholine) made impossible to use this last technique in thawed samples. When sperm viability was assessed by Hoechst staining, a significant decrease of approximately 15% (73.10 vs 58.26%) of alive spermatozoa was registered from fresh to thawed samples. The percentage of motile cells measured by CASA in fresh samples (51.9%) was lower than the percentage of alive cells determined by Hoechst stainning, suggesting the existence of different batches of spermatozoa in different stages of development, even during the eight to tenth weeks of treatment, when the highest sperm quality was found.  相似文献   
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Plasma concentrations of glucose and insulin following a meal were compared in twelve Thoroughbred mares fed a pelleted concentrate (PC), a traditional sweet feed high in sugar and starch (SS), or a feed high in fat and fiber (FF). The feeds had similar DE and CP but differed in fat (19, 32, and 166 g/kg DM, respectively), NDF (199, 185, and 369 g/kg DM, respectively) and nonstructural carbohydrates (574, 645, and 247 g/kg, respectively). Mares were randomly assigned to two groups balanced for foaling date and weight. All mares received PC in late gestation; then, after foaling, one group was fed SS and the other FF for trials in early and late lactation. Mares were placed in stalls and deprived of feed overnight. A series of blood samples was collected via a jugular catheter from 0 (baseline) to 390 min after consumption of 1.82 kg of feed. Plasma was analyzed for glucose and insulin. Baseline values, peak values, and areas under curves (AUC) were compared by ANOVA. Baseline values were 74.7 +/- 10.9 mg/dL for glucose and 5.86 +/- 1.80 mIU/L for insulin for all diets and stages. Responses to PC did not differ between the two groups (P > 0.34), indicating the groups were metabolically similar. Peak plasma glucose and insulin concentrations were higher (P < 0.001) in the SS group than in the FF group during early and late lactation. Similarly, glucose and insulin AUC were larger (P < 0.003) in SS than in FF during early and late lactation. These results indicate that metabolic fluctuations are moderated by the replacement of sugar and starch with fat and fiber. This replacement may reduce the risk of certain digestive and metabolic disorders that have been linked to feeding meals of grain-based concentrates to pregnant or lactating mares.  相似文献   
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Groups of four pregnant ewes were allocated to the following feeding and intravenous endotoxin treatments: fed, Escherichia coli endotoxin (50 micrograms/kg X 75), fed, saline, fasted, E. coli endotoxin (50 micrograms/kg X 75) and fasted, saline. Endotoxin administration resulted in depression, fever, hypoglycemia, hypocalcemia and a reduction in nonesterified fatty acid and ketone body concentrations. Depression correlated best with body temperature (r = 0.76), fasted sheep showed smaller increases in body temperature and were less depressed following endotoxin. Three of eight endotoxin treated sheep died, mortality was not related to rectal temperature but was associated with lactic acidosis. Hypoglycemia was not associated with either death or depression. Fed sheep that were unable to stand had lower serum calcium concentrations than standing sheep.  相似文献   
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SUMMARY The need for dietary management of renal senescence and the beginning of chronic renal failure should be evaluated in all middle-aged dogs. One survey found that 35% were overweight and 10% underweight; another that 25% were mildly azotaemic, with 5% showing slight clinical signs of chronic renal failure. Dogs in prime condition or overweight are candidates for a diet low in energy (for example 3.0–3.3 kcal/g dry matter, DM), but thin dogs need a higher caloric density (such as 4.0–4.5 kcal/g DM). Healthy older dogs need higher dietary protein than the minimum for maintenance (about 20% on a metabolisable energy basis, ME) of young mature dogs. Thin older dogs showing signs of renal insufficiency may benefit from moderate protein and near-minimal phosphorus in the diet. In dogs with chronic renal failure, clinical, haematological and biochemical responses to the combination of low protein (13–16% ME) and low phosphorus (0.4% DM) were positive in one clinical trial but not in three others. Only beneficial responses, such as less proteinuria, less renal impairment and lower mortality, have been reported for diets containing low phosphorus and moderate protein (20–31% ME). Individual dietary goals for energy, protein and phosphorus should be chosen for each middle-aged or older dog; these goals may be met by a single product or mixtures of products.  相似文献   
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