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It was demonstrated experimentally that bloodsucking dipterans (gad-flies, gnats, midges, black flies) influenced negatively weight increments of grazing heifers and that it was suitable to treat the heifers with repellents; 10% water emulsion of the repellent diethyltoluamide was used for heifer spraying in the intervals of 48 hours. Over the 66 days of the experiment, the total live weight of one heifer from the test group increased by 5.00 kg, in comparison with the controls. The coefficient of loss per untreated animal was 105.00 Kcs., the returns of investments per 1.00 Kcs of investment costs were 1.90 Kcs. Owing to worse climatic conditions in the experimental years which significantly differed from meteorological conditions in the previous four years, which ensued from mathematico-statistical evaluation, differences in weight increments over the period of study were statistically insignificant.  相似文献   
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The change of haptoglobin concentration in cattle with dystocia after torsio uteri which lead to Caesarean section is regarded in contrast to haptoglobin concentrations in cattle at parturitions with undisturbed puerperium and Caesarean section without torsio uteri intra partum. Animals with natural parturition had low haptoglobin concentrations with slight changes, for a slightly increased haptoglobin concentration was seen as physiologic. Also surgical treatment such as Caesarean section did not result in changes of haptoglobin concentration. Thus, the curve of animal patients with anomalies concerning position or with a too large fetus (relatively or absolutly) was nearly identical to the curve of animals with regular parturitions over the first four days after surgery. Not before the fifth day after surgery, a moderate increase of haptoglobin could be observed. Animals with dystocia after torsio uteri intra partum showed significantly higher haptoglobin concentrations in contrast to controls over the time of investigation. The correlation of haptoglobin concentrations in animal patients with torsio uteri bin concentration shortly after surgery an additionally significant increase of haptoglobin concentration could be observed in later fertile cattles but not in later infertile cattle with torsio uteri. In two cows with torsio uteri and ovariohysterectomy haptoglobin concentrations decreased rapidly. Haptoglobin concentration may serve as an indicator for the degree of impairment of the uterus during a parturition as well as a predictor for regenerative potential.  相似文献   
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The present study was conducted to evaluate the effect of chromium (Cr) from Cr yeast on the growth performance and total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglycerides, glucose, total protein and Cr concentration in the serum of broiler chicken. The birds were fed a control diet or a control diet supplemented with Cr at a level of 300, 500 microg/kg Cr. The supplementation of 500 mug/kg Cr increased body weight, weight gain and feed efficiency (p < 0.05). In addition, supplementation with Cr decreased the serum total cholesterol, LDL cholesterol (p < 0.05), triglycerides (p < 0.05) and glucose (p < 0.05) concentrations whereas serum HDL cholesterol increased. Serum total protein and serum Cr concentration slightly but not significantly increased in both Cr groups. The study suggest that Cr supplementation particularly at 500 microg/kg Cr from Cr yeast can influence on carbohydrate and lipid metabolism of broiler chicken and can be used as additives in animal diet but it still needs more investigations.  相似文献   
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