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1. Seventeen 32-week-old White Leghorn laying hens were induced to become deficient in calciferol or in calcium (laying thin or soft shelled eggs) by withdrawing either cholecalciferol (27.5 micrograms/kg diet) or calcium (31 g/kg diet) supplements from the control diet. 2. The metabolic fate and metabolic clearance rate (MCR) of intravenously injected 3H-oestradiol-17 beta were then monitored for 40 min. 3. In both the calciferol and calcium-deficient groups a major oestrogen sulphate pathway was particularly affected, resulting in a decreased conversion of oestradiol-17 beta-3-sulphate to oestradiol-17 alpha-3-sulphate, with a concomitant reduced MCR of oestradiol-17 beta from plasma. 4. The metabolic defect was corrected by feeding the control diet. 5. Because the metabolic defect observed in calciferol deficiency occurred in Ca deficiency in a more severe form, we conclude that the more immediate cause was calcium rather than calciferol deficiency. To our knowledge, this is the first observation of a calcium-deficient effect on oestrogen sulphate metabolism in vivo. 相似文献
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SUMMARY Weaned lambs were infected with Haemonchus contortus 35,28,21,14 and 7 days after treatment with moxidectin at 0.2 mg/kg and 35 and 14 days after treatment with ivermectin at the same dose rate. Worm counts 14 days after infection showed that moxidectin prevented the establishment of over 99% of infective larvae for 28 days and reduced the establishment rate at 35 days by 96%, relative to ivermectin. There was no difference in the protective efficacy of ivermectin at 14 or 35 days. The persistence of moxidectin is likely to provide advantages in nematode control, particularly when used as a strategic early summer treatment or as a pre-lambing treatment to ewes. Implications of the persistent activity of moxidectin for the development of resistance during the decay phase are discussed. 相似文献
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de Almeida Daniel Mageste Marcondes Marcos Inácio Rennó Luciana Navajas Pereira Silva Luiz Henrique Martins Leandro Soares Marquez David Esteban Contreras Castaño Villadiego Faider Alberto Velez Saldarriaga Felipe Franco Julian David Castaño Moreno Deilen Paff Sotelo de Moura Felipe Henrique Paulino Mário Fonseca 《Tropical animal health and production》2019,51(1):79-87
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of strategic supplementation in the dry period and dry/rainy transition period on the performance and... 相似文献
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The Importance of Wild Canids in the Epidemiology of Rabies in Northeast Brazil: A Retrospective Study 下载免费PDF全文
R. de A. Cordeiro N. F. H. Duarte B. N. Rolim F. A. Soares Júnior I. C. F. Franco L. L. Ferrer C. P. Almeida B. H. Duarte D. B. de Araújo M. F. G. Rocha R. S. N. Brilhante S. R. Favoretto J. J. C. Sidrim 《Zoonoses and public health》2016,63(6):486-493
Rabies is an endemic disease in Brazil, where it is considered a serious public health problem. Although the number of human and dog‐transmitted cases has declined in recent decades, rabies in wildlife has emerged considerably. Among the sylvatic animals, wild canids have been considered important hosts of the rabies virus. We performed a retrospective study of reported cases of rabies in wild canids and human victims in Ceará state (Northeast Brazil) during 2003 to 2013. Information was provided by governmental laboratories involved in rabies detection and by the Ministry of Health. From January 2003 to December 2013, a total of 11 931 animal samples were examined for rabies. Positivity were detected in 438 samples (3.67%), of which 229 (52.28%) were domestic animals, 105 (23.97%) wild canids and 104 (23.74%) other wild animals (bats, marmosets and raccoons). Approximately 33% of wild canids surveyed (n = 317) were positive for rabies. During the studied period, a total of 1923 attacks on humans by wild canids were registered. Males (n = 1405) were more affected than females (n = 520; 72.98% versus 27.01%), and the median age of all cases was 36.5 years. Injuries to individuals up to 19 years old corresponded to approximately 30% (n = 565) of all cases. Most of the victims lived in rural areas (72.46%; n = 1395), and the majority showed bites (81.13%; n = 1677) or scratches (12.23%; n = 253). Injuries were considered profound (52.1%; n = 1003), superficial (40.91; n = 788) or multiple with severe laceration (6.98%; n = 134). Only 1300 (67.53%) victims were enrolled for the complete rabies post‐exposure prophylaxis scheme. Data from the present study confirm that wild canids are important hosts of rabies virus in northeastern Brazil and jeopardize rabies control in this area. Local authorities should focus their efforts in education of health professionals. In addition, strategies should be formulated to preserve wildlife. 相似文献
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