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991.
Schlerka G Tataruch F Högler S Url A Krametter R Kössler D Schmidt P 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(1-2):52-56
In a dairy herd of 21 cows which were on pasture during the day at the end of May 2002, four eight years old cows were suddenly inappetent and showed severe diarrhoea consisting of black discolorate feces. A few days after the onset of the disease, three affected cows exhibited neurological disorders. These cows were admitted to the IInd Medical Clinic of the University for Veterinary Medicine in Vienna. Following clinical signs were observed: circulatory weakness, anorexia, atony of the rumen, diarrhoea and in accordance with acute lead poisoning typical signs of the central nervous system. One cow died and the other two animals were euthanized. Results of blood testing were anaemia, basophil spotting of erythrocytes, increase of liver enzymes and CK, hypocalcaemia, decrease of potassium and phosphate. The cerebrospinal fluid of two cows showed increased CK-, LDH- and AST-values. The lead contents of whole blood samples were between 0.486 and 0.928 mg/kg, of liver samples 13.3 to 114.4 mg/kg, of kidney samples 172.2 to 448 mg/kg and of rumen content 59 mg/kg fresh matter. At necropsy, enteritis, liver fluke disease and severe interstitial and alveolar pulmonary emphysema were found. Pathohistologically typical ischaemic necrosis of neurons predominantly at the tips of the gyri, disseminated petechial hemorrhages and moderate diffuse neovascularisation, but no acid-fast intranucleolar inclusion bodies in the renal tubules were observed. As causative agent of the acute lead poisoning a residue on combustion, taken up by the cows on the pasture, was confirmed. The ash residue was formed by combustion of three tires which contained 450 g heavy weights of 96.5% lead for wheel balance. The lead content of the ash residue was between 2.9 and 28 g/kg dry matter. 相似文献
992.
The hCG induced ovulation in sows was studied by use of ultrasonography, and an investigation of the development and diversity of the zygotes/embryos was performed at 24 h after ovulation. Crossbred sows (N = 48) were weaned (day 0) and checked for heat twice daily from day 3 onwards. From day 4, the ovaries were transrectally scanned twice daily. On day 4, the sows were given an injection of 750 iu hCG i.m. and inseminated 27 +/- 2 h (X +/- SD) and 38 +/- 1 h later. From 38 to 48 h after the hCG injection, the ovaries were scanned at 60 to 90 min intervals. At 24 h after ovulation the oviducts were surgically flushed in 18 sows. Out of the 48 sows, 34 showed heat at 12-36 h after the hCG-treatment and 14 showed heat before the hCG treatment. In the former group of sows, 20 (59%) ovulated within the interval of 38 to 48 h after the hCG treatment, and the follicular size immediately before ovulation was 7.8 +/- 0.6 mm. Among the sows which showed heat before hCG treatment only 7 (50%) ovulated within the above interval and the preovulatory follicle size was larger (8.3 +/- 0.5, p < 0.05) than in the former group of sows, which showed heat after the hCG treatment. The flushing of 18 sows yielded a total of 243 ova, 70 (29%) 1-cell stages, 160 (66%) 2-cell stages and 13 (5%) 4-cell stages. A pronounced difference in the degree of variation in embryonic development was seen between sows: 4 animals yielded 1- to 4-cell stages, one exclusively 2-cell stage. In conclusion, the control of ovulation in sows by hCG treatment will affect the follicular growth and the exact timing of ovulation can not always be relied on. It is strongly recommended to use ultrasonography to monitor the time of ovulation if this parameter is important. Ova recovered at 24 +/- 1 h after the median time of ovulation revealed a pronounced diversity (1- to 4-cell stage) within sows. No obvious relation with this embryonic diversity and the follicular size at ovulation was seen in these data. 相似文献
993.
Ty B Schmidt K C Olson 《Veterinary Clinics of North America: Food Animal Practice》2007,23(1):151-163
The ultimate goal of feeding beef cattle is to develop a meat product that satisfies consumer needs. Nutritional management plays a significant role in determining carcass merit of beef cattle. Certain management procedures (eg, metabolic modifiers, early weaning), general animal health (eg, history of respiratory disease), and certain feed ingredients (eg, trace minerals, antioxidants) can have positive and negative effects on the overall quality of beef that is supplied to the consuming public. 相似文献
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Immunization of foxes with inactivated-virus rabies vaccine 总被引:1,自引:0,他引:1
997.
O C Schmidt 《Berliner und Münchener tier?rztliche Wochenschrift》1970,83(20):396-397
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The use of plant protection products requires precise forecasting of the susceptible larval stages of the grape berry moths Lobesia botrana and Eupoecilia ambiguella as these dynamics vary with the weather pattern of a particular year. The objective of this research has been to partition the relative influence of specific climatic factors on the dynamics of these insects. Data taken from 7 years of continuous monitoring of the flight occurrence of male adults, and of the following development stages (i.e. eggs and larvae), was analysed by a generalized Leslie process. The model type reduces the population to three probabilities: development, survival and fertility. Each probability can be modelled as a function of the associated weather factors, while the functional relationships and the model parameters are established. The analysis started with the simplest approach and, in a step‐by‐step procedure, model complexity was added until a sufficient fit to the overall data set was achieved. Within the magnitude of the model, development rates were controlled solely by temperature, but the duration of single stages (i.e. survival) was found to be affected by a combination of temperature and relative humidity. The model represents a combination of mechanisms within a season with empirical components. 相似文献