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51.
Masahiro Osada Hitomi Iwabuchi Toru Aoki Kika Sasaki Hitoshi Ushijima Takeyuki Ozawa 《Animal Science Journal》2019,90(4):597-603
Artificial insemination using sex‐sorted semen is employed to efficiently increase the number of female dairy calves born. Previous studies have determined that using sex‐sorted semen is beneficial to improve the management, but the mechanism by which it increases cattle numbers through objective indices of breeding remains unclear. This study focused on a Brown Swiss cattle herd in which frozen female sex‐sorted semen was systematically employed to increase the number of cattle. We analyzed the correlation between the increase in the number of cattle and the screening accuracy of sex‐sorted semen, measuring indices such as pregnancy rate and birth rate of female calves. Study revealed that: (1) production cost for female calves is influenced by the pregnancy rate, rate of female calves, and using sex‐sorted semen is less expensive than using nonsorted semen; (2) improvements in screening accuracy nearly doubled the number of cows and tripled the number of heifers in 5 years; and (3) use of sex‐sorted semen improved milk quality. The pregnancy rate was lower when sex‐sorted semen was used, but the birth rate of heifers was improved. Results suggest that artificial insemination using sex‐sorted semen is beneficial because it economically produces offspring to increase the herd. 相似文献
52.
Hamid Reza Taheri Hadi Nasiri Rasoul Ahmadkhani 《Journal of animal physiology and animal nutrition》2019,103(4):1090-1098
This study investigated effect of increasing level of dietary sodium using sodium bicarbonate or sodium chloride on growth performance, mortality, characteristics of carcass, organs and tibia, calcium and phosphorus of serum in broilers reared in a high‐altitude area (1,700 m above sea level). A total of 588 Ross 308 male broiler chicks were used in seven treatments, six replicates per treatment of 14 birds per each from 1 to 38 d of age. Seven dietary treatments consisted of a basal diet (with 0.16% sodium and 0.23% chloride), top‐dressed for six diets to give three supplementary levels of sodium (0.07%, 0.14% and 0.21%) from sodium bicarbonate (respectively by 0.26%, 0.52% and 0.78%) or sodium chloride (respectively by 0.18%, 0.36% and 0.54%), resulting in seven diets with total sodium and chloride levels of 0.16% and 0.23%, 0.23% and 0.23%, 0.30% and 0.23%, 0.37% and 0.23%, 0.23% and 0.33%, 0.30% and 0.44%, 0.37% and 0.55% respectively. Increasing sodium level improved feed conversion ratio (FCR) linearly and quadratically. However, when FCR was calculated without adjusting for feed intake of mortalities, the enhanced sodium level did not improve this parameter. Increasing sodium level via sodium chloride enhanced ascites mortality, total mortality, relative weight of heart and right ventricle linearly. Increasing sodium level reduced serum calcium and enhanced serum phosphorus linearly; however, there was a linear tendency to increase tibia ash when sodium level was enhanced by sodium bicarbonate (p = 0.08) or sodium chloride (p = 0.07). Increasing sodium level via sodium bicarbonate tended (p = 0.08) to reduce tibia strength linearly. In conclusion, a diet with 0.16% sodium and 0.23% chloride is enough for broiler chicken reared in a high‐altitude area, and increasing dietary sodium level via sodium chloride has detrimental effect on survivability of broiler in such condition. 相似文献
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开展生物多样性动态长期监测,了解生态系统结构与功能变化,探明生物多样性变化过程及影响因素是制定有效保护措施的重要基础。本研究在内蒙古赛罕乌拉国家级自然保护区开展10年野生动物多样性动态监测,新发现保护区分布哺乳动物7种、鸟类98种,内蒙古鸟类新纪录2种,内蒙古蛇类新纪录1种。但也未发现一些以往有记录的物种,需要进一步强化野生动物多样性监测,探明物种变化的原因。后续监测工作引入了非损伤采集动物粪样提取DNA技术,从而深入了解保护区野生动物种群长期稳定的遗传学和空间分布特征,为有效管理自然保护区珍稀野生动物提供科技支撑。 相似文献
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Keisuke SASAKI Hideo AIZAKI Michiyo MOTOYAMA Hideyuki OHMORI Tomoyuki KAWASHIMA 《Animal Science Journal》2011,82(1):175-180
Impressions and purchasing intentions of Japanese consumers regarding pork produced by ‘Ecofeed’, a trademark of food‐waste or co‐product animal feeds certified by the Japanese government, were investigated by a questionnaire on the Internet. ‘Ecofeed’ did not elicit specific impressions as compared to domestic, imported, Kurobuta (in Japan), and specific pathogen‐free (SPF) pork. Purchasing intent for ‘Ecofeed’ pork was the second lowest of the five pork products. Knowledge and purchasing experience regarding ‘Ecofeed’ pork was the lowest of the five pork products. Respondents were classified into four categories according to their impressions of ‘Ecofeed’ pork. The largest category of respondents did not have any specific impression of ‘Ecofeed’ pork and had little knowledge of pork farming. A category that had a positive impression for ‘Ecofeed’ pork had high knowledge of the pork farming system. In order to establish ‘Ecofeed’ pork in Japan, our results suggest that information disclosure and education about ‘Ecofeed’, its certification system, environmental benefits and the current self‐efficiency ratio of animal feed, are needed. 相似文献
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58.
- 1. Wetlands are declining worldwide, and there is a great need for their restoration and creation. One natural agent of wetland engineering is beavers, Castor spp., which have returned or are returning to many parts of their former range.
- 2. We initially studied the facilitative effect of the beaver Castor canadensis on a waterbird community consisting of three waders and four ducks in boreal wetlands in southern Finland. Both waterbird species diversity and abundance increased when beavers impounded a pond. Common teal Anas crecca and green sandpiper Tringa ochropus were the species showing the most positive numerical response, but the other five species also increased upon flooding.
- 3. This article evaluates how the results of the study have been used in management, both in theory and practice. The whole‐community facilitation concept has been taken up in numerous articles considering the restorative effects of beavers. It has also been used as ecological background when planning and executing man‐made wetland projects in Finland within both the public and the private sectors.
- 4. Our study and its publication in Aquatic Conservation: Marine and Freshwater Ecosystems have set a foundation for further evidence‐based management of waterbird communities. As the results show, having beavers as wetland managers is a feasible tool for creating and restoring wetlands for waterbirds and other biota. Moreover, wetland restoration projects are becoming more popular endeavours, owing to an understanding of the diverse benefits of wetlands. Flooding by beavers is used as a model for managers when creating man‐made wetlands; for example, in urban areas where it is difficult to maintain beavers.
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60.
Bröker M 《Zoonoses and public health》2012,59(3):176-180
In Central Europe and large parts of Asia, tick-borne-encephalitis (TBE) and Lyme borreliosis caused by the spirochetal bacterium of the genus Borrelia are among the most common diseases transmitted by the bite of a tick. When in regions with overlapping TBE virus and Borrelia endemicity, a tick bite causes the victim to become ill, it is important that appropriate serological and other laboratory investigations form part of the differential diagnosis. Account must always be taken of the fact that a tick bite may be followed by a double infection with the TBE virus and Borrelia. For this reason, a comprehensive diagnostic work-up aimed at detecting co-infection by both pathogens, even when the tick bite occurs in an endemic region for both pathogens but the initial clinical symptoms suggest an infection with only one of the two pathogens. The present article discusses a number of published cases of a co-infection with TBE virus and Borrelia and other potential multiple infections. 相似文献