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31.
Variations in parameters of liver function and plasma progesterone related to underfeeding and ketosis in a dairy herd 总被引:2,自引:0,他引:2
Twenty-eight Norwegian Red Cattle dairy cows were fed silage ad libitum and restricted amounts of concentrates. Blood samples were collected before morning feeding, once or twice weekly, from 2 weeks before to 12 weeks after calving. Parameters of liver function, carbohydrate status and fertility were recorded in order to assess their interrelationships. Eight cows were treated for clinical ketosis. Four of these had to be treated 2 or 3 times. Aspartate aminotransferase and bilirubin showed the highest within-animal coefficients of correlation with acetoacetate. Analysis of variance revealed a significant effect of carbohydrate status (indicated by plasma acetoacetate levels) on the levels of aspartate aminotransferase, glutamate dehydrogenase and sorbitol dehydrogenase, though only a small part of the total variation was explained by this factor. The estimated volume density of liver fat in the 4th week of lactation averaged 6.0 +/- 6.4% (+/- SD) ranging from 0.1-25.1%. Liver fat content at this stage of lactation was not significantly correlated with other indicators of liver function or carbohydrate status. Cows treated for clinical ketosis had significantly lower plasma progesterone values at the time of first ketosis treatment than untreated multiparous cows. The frequency of high progesterone values (greater than 3 ng/ml) being significantly lower in treated than in untreated cows during the period from 3-5 weeks post partum, though not at later stages. In conclusion, the results revealed a significant relationship between carbohydrate status and liver function, and also between clinical ketosis and luteal function. 相似文献
32.
D V Wilson 《Veterinary Clinics of North America: Small Animal Practice》1992,22(2):491-494
Any patient presenting for anesthesia and surgery who has a severe debilitating problem is at great risk for a prolonged recovery, renal failure, or hypotension. A stable hemodynamic state should be maintained. Fluid homeostasis should be ensured. Anesthetic induction techniques using narcotics and benzodiazepines are my preferred approach, with maintenance of anesthesia incorporating isoflurane, narcotics, or both or the use of regional anesthesia. 相似文献
33.
D C Lay T H Friend R D Randel C L Bowers K K Grissom O C Jenkins 《Journal of animal science》1992,70(2):330-336
Twenty-seven crossbred calves (1/2 Simmental, 1/4 Hereford, 1/4 Brahman) averaging 257 +/- 11 d of age were either hot-iron-branded (H), freeze-branded (F), or sham-branded (S). Calves were blocked for temperament, weight, and sex and were randomly assigned to day and order in which treatments were applied. To reduce stress from handling at treatment time, each calf was herded through the squeeze chute daily for 5 d before the experiment. Jugular cannulas were inserted in each calf 1 d before application of treatment. Blood samples and heart rate measures were obtained at -5, -3, 0, .5, 1, 3, 5, 10, 15, and 20 min after application of the treatments. Mean concentrations of plasma epinephrine (EPI) were higher for H calves at time .5 min than for either S or F calves (P = .10). To account for individual differences, prebranding heart rates and hormone concentrations were subtracted from subsequent samples and were also used to calculate a proportion for each subsequent sample. Analyses of subtracted values found that EPI concentrations were greater for H calves than for either S or F calves (P = .007) at .5 min postbranding. No other differences were found for the subtracted analyses. Analyses of proportion data also revealed that H calves had greater EPI than did either S or F calves (P = .027) at .5 min postbranding. Only three animals vocalized during branding, one H calf and two F calves. Despite the 5-d acclimation period, handling and restraint elevated plasma cortisol concentrations and heart rate.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
34.
The indirect fluorescent antibody test (IFAT) was compared with the enzyme-linked immunosorbent assay (ELISA) for the detection of specific antibodies to Sarcocystis sp. A set of 275 ovine blood samples was examined by both reactions. Cystozoites of Sarcocystis gigantea were used as the corpuscular antigen for the IFAT. For the diagnostics of sarcocystosis by the ELISA technique used the sandwich test of the antibody titration with a soluble antigen which was also prepared from S. gigantea macrocysts. Our studies confirmed that this antigen did not cross-react with Toxoplasma gondii. Titre 40 was determined as the limit one for the IFAT and titre 80 for the ELISA; which was confirmed by the direct detection of cysts in the muscles (Svobodová, 1989). The results of both methods are shown in Table I. 76.7% of the blood samples reacted positively in the IFAT and 83.6% in the ELISA. These methods were found to be suitable and can be utilized for the intravital routine diagnostics. 相似文献
35.
Abstract. The effect of Medicago arborea on erosion on a burnt area was studied in experimental plots near Valencia, Spain, between 1989 and 1992. Its growth and development was studied, and its effect was compared with the natural vegetation (matorral) and bare soil. Medicago decreased soil loss by 41.7% and runoff by 25.7% compared with bare soil. However, under natural vegetation soil loss was 27.5% less than under Medicago. 相似文献
36.
D E Gunson P S Sahota W O Iverson R Y Chau G M McCormick V M Traina 《Veterinary pathology》1992,29(2):145-151
Male and female Sprague-Dawley rats were given CGS 21595, a pro-drug that is almost immediately metabolized to CGS 19213, a naphthoquinone that acts as a 5-lipoxygenase inhibitor. The compound was administered by gavage to five groups of Sprague-Dawley rats (group Nos. 1, 5, n = 30; group Nos. 2-4, n = 20) at daily doses of 0, 50, 150, 500, or 1,000 mg/kg for 13 weeks. Rats in the higher dose groups had a reduced weight gain, but significant neurologic signs were not observed. A peripheral neuropathy consisting predominantly of myelin destruction in the spinal nerve roots and sciatic nerves in male rats treated with greater than or equal to 150 mg/kg CGS 21595 and in female rats treated with greater than or equal to 50 mg/kg CGS 21595 for 13 weeks. This lesion was not fully reversible after a recovery period of 4 weeks. Lesions consisted of ballooning of myelin sheaths, infiltration by macrophages, demyelination, and occasional areas of remyelination. Axons were generally preserved, and the brain and spinal cord were not affected. Male and female rats in all treatment groups had cytoplasmic hyaline droplets in the proximal renal tubules. This change was reversible after 4 weeks and was not associated with any other adverse effects on the kidney. 相似文献
37.
The results of cerebrospinal fluid (CSF) cytology of 9 dogs with brain tumors and 50 dogs with spinal cord compression are discussed. Of the 50 dogs with spinal cord compression, disc protrusion was diagnosed in 31, myelomalacia in 7, discospondylitis in 3 and spinal cord tumors in 9 dogs. In 4 of 9 dogs with brain tumors, tumor cells could be found by the sedimentation apparatus of K?lmel. Pleocytosis existed in 6 patients. In about 70% (29 of 41) of cases with disc protrusion, more than 200 cells could be evaluated in the CSF sediment, consisting mostly of transformed lymphocytes and activated monocytes. As the neurologic deficits increased, the amount of cells and especially cell complexes increased. This was especially evident in cases with myelomalacia of the spinal cord. Only in cases with discospondylitis or spinal cord neoplasia was the CSF cytology unchanged. 相似文献
38.
Abstract – Foraging juvenile fish with relatively high food demands are usually vulnerable to various aquatic and avian predators. To compromise between foraging and antipredator activity, they need exact and reliable information about current predation risk. Among direct predator-induced cues, visual and olfactory signals are considered to be most important. Food intake rates and prey-size selectivity of laboratory-reared, naive young-of-the-year (YOY) perch, Perca fluviatilis , were studied in experiments with Daphnia magna of two size classes: 2.8 and 1.3 mm as prey and northern pike, Esox lucius , as predator. Neither total intake rate nor prey-size selectivity was modified by predator kairomones alone (water from an aquarium with a pike was pumped into the test aquaria) under daylight conditions. Visual presentation of pike reduced total food intake by perch. This effect was significantly more pronounced (synergistic) when visual and olfactory cues were presented simultaneously to foraging perch. Moreover, the combination of cues caused a significant shift in prey-size selection, expressed as a reduced proportion of large prey in the diet. Our observations demonstrate that predator-induced olfactory cues alone are less important modifiers of the feeding behaviour of naive YOY perch than visual cues under daylight conditions. However, pike odour acts as a modulatory stimulus enhancing the effects of visual cues, which trigger an innate response in perch. 相似文献
39.
Definitions of the notions of soil resilience and degradation of the soil-vegetation cover are suggested. These problems are considered with respect to vulnerable tundra ecosystems. The analysis of available experimental data made it possible to obtain empirical equations characterizing the relationships between the plant productivity and the soil properties. These equations can be used to predict the degree of soil degradation under particular types of technogenic loads and the soil and vegetation potential for the natural restoration or artificial rehabilitation of the soil-vegetation cover in tundra ecosystems. The results obtained can be applied for the development of optimal nature management strategies in the areas of oil and gas fields in the north. 相似文献
40.
Validation of the accuracy of household reporting of subsistence fishing catch and effort: a Fijian case study 总被引:1,自引:0,他引:1
Abstract The accuracy of household reporting of subsistence fishing catch and effort and seafood consumption on the Fijian island of Ono-i-Lau was studied. A creel survey was carried out concurrently to validate the household survey data. Reported estimates of fishing participation, effort, and fish consumption were not significantly different to the creel survey estimates. Householder's appeared to overestimate the number of fish from the most abundant family Lethrinidae, and underestimate rarer fish. However, there was no significant difference between the reported and observed contribution of the majority of finfish families and invertebrate taxa. The reported and observed catch rate estimates were not significantly different, indicating that Ono-i-Lau villagers are relatively accurate in their estimation of the number and size of fish from recalled catches. 相似文献