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41.
Adkin A England T Hall S Coburn H Marooney CJ Seaman M Cooper J Hartnett E 《The Veterinary record》2008,163(8):235-240
A quantitative risk assessment model was developed to estimate the frequency with which meat waste from ships or aircraft might expose British livestock to infection with foot-and-mouth disease (fmd), and investigate the factors that might contribute to the risk. In the model, the total weight of waste introduced that was contaminated with fmd was estimated to be 26 kg per year, with 90 per cent certainty that it would be between 10 and 53 kg. As a result, it was estimated that there would be a mean of 1429 years between outbreaks of fmd due to ship and aircraft waste, with a 90 per cent certainty that the interval would be between 500 and 10,000 years. These estimates were affected by three principal uncertainties: first, the prevalence of fmd; secondly, the probability of the waste being removed and fed to pigs; and thirdly, the probability that overboard dumping of contaminated waste might expose livestock to fmd. The effect of these uncertainties on the model was investigated in a sensitivity analysis. 相似文献
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Histological examination of the reproductive tract of the male dog failed to identify glandular tissue other than the prostate gland and its disseminated portion. A biochemical study of the three fractions of the ejaculate demonstrates similarities between the first and the third fractions. The composition of three ejaculates collected over 12 hours indicated that storage of prostatic secretion was a possible explanation for the biochemical differences observed. It is suggested that both the first and third fractions originate from the prostate gland. 相似文献
44.
Cryptosporidiosis in immunodeficient Arabian foals 总被引:9,自引:0,他引:9
Five of six immunodeficient Arabian foals that died of adenoviral infection were found to be infected with an intestinal coccidian of the genus Cryptosporidium. Various developmental stages of the organism were found in the microvillous border of the intestinal mucosa. The foals had diarrhea but it was not possible to separate the effects of the cryptosporidial infection from those of the concomitant adenoviral enteritis. 相似文献
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KC Silva‐Santos GMG Santos C Koetz Júnior F Morotti LS Siloto TN Marcantonio MR Urbano RL Oliveira DCM Lima MM Seneda 《Reproduction in domestic animals》2014,49(2):228-232
Interest in indicus–taurus cattle has been increasing, as these animals are likely to present the best characteristics of Zebu and European bovine breeds. The aim of this study was to compare the embryo production of indicus–taurus donors with high vs low antral follicle counts obtained by ovum pickup/in vitro production (OPU/IVP) and superovulation (SOV)/embryo collection. Braford females at weaning age (3/8 Nelore × 5/8 Hereford, n = 137, 9 ± 1 month old) were subjected to six serial ovarian ultrasonographs and were assigned to two groups according to the number of antral follicles ≥3 mm as follows: G‐High antral follicular count (AFC, n = 20, mean ≥40 follicles) and G‐Low AFC (n = 20, mean ≤10 follicles). When the females (n = 40) reached 24 months of age, they were subjected to both OPU/IVP and SOV/embryo collection. The average number of follicles remained highly stable throughout all of the ultrasound evaluations (range 0.90–0.92). The mean number of COCs recovered (36.90 ± 13.68 vs 5.80 ± 3.40) was higher (p < 0.05) for females with high AFC, resulting in higher (p < 0.05) numbers of total embryos among females with high vs low AFC (6.10 ± 4.51 vs 0.55 ± 0.83). The mean number of embryos per collection was also higher (p < 0.05) for G‐High vs G‐Low (6.95 ± 5.34 vs 1.9 ± 2.13). We conclude that a single ultrasound performed at pre‐pubertal ages to count antral follicles can be used as a predictor of embryo production following IVP and SOV/embryo collection in indicus–taurus females. 相似文献
49.
Alteration of the Allende meteorite caused shifts in oxygen isotope ratios along a single mass fractionation line. If alteration was caused by aqueous fluid, the pattern of oxygen isotope fractionation can be explained only by flow of reactive water down a temperature gradient. Down-temperature flow of aqueous fluid within planetesimals is sufficient to explain the mineralogical and oxygen isotopic diversity among CV, CM, and CI carbonaceous chondrites and displacement of the terrestrial planets from the primordial slope 1. 00 line on the oxygen three-isotope plot. 相似文献
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African origins of the domestic donkey 总被引:1,自引:0,他引:1