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《African Zoology》2013,48(3):249-257
Understanding fish movement patterns and migrations is important for fisheries management as well as the identification and conservation of critical habitats. Data collected by the Oceanographic Research Institute's Cooperative Fish Tagging Project (ORI-CFTP) were used to describe the large-scale movement patterns of Lichia amia along the South African coastline. A total of 10 762 L. amia were tagged between 1984 and 2012, of which 744 (7%) were recaptured. Most tagging effort, mainly on juvenile and subadult individuals, took place along the south-eastern (i.e. Eastern Cape) and south-western (i.e. Western Cape) regions of the country during summer. Conversely, more L. amia were tagged and recaptured (mostly adults) during winter and spring (July to November) along the north-east coast (i.e. KwaZulu-Natal). Movements (dispersal distance in kilometres) by juveniles were restricted and largely confined to estuaries within the south-eastern and south-western regions of the country. There was a significant effect of fish size on distance moved (ANOVA: p<0.001), with evidence of a distinct seasonal (winter) longshore migration by adults to KwaZulu-Natal. The consequences of juvenile residency in estuarine habitats and high recapture rate of adults during a directed, seasonal spawning migration are discussed in light of improving current fisheries management. 相似文献
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对240头牦母牛进行为期一年的体况评分监测,发现牦母牛体况变化与草地饲草的供给状况相一致,牦母牛体况变化基本规律为暖季表现为快速上膘,冷季呈现逐步消耗。体况评分最低的时期为5~6月份,最高在10月和11月份。体况消长变化呈现两年一周期的模式。 相似文献
106.
电子商务的蓬勃发展给企业管理带来巨大冲击,财务管理作为企业管理链条上的重要一环,其管理模式也因此而发生了重大变革。文中首先介绍了网络财务管理产生的背景及其概念,讨论了网络财务管理的优势所在,明确了网络财务管理产生和发展的技术基础,重点对网络财务管理的开发与实施展开了探讨。 相似文献
107.
断奶日龄对仔猪Et玫瑰花环形成率和T淋巴细胞转化率的影响 总被引:7,自引:0,他引:7
选取15窝杜洛克×长白×约克夏三元杂交初生仔猪 ,按14、21、28、35日龄断奶和不断奶随机分为5组(14E、21E、28E、35E、C) ,每组3窝 ,研究断奶及不同断奶日龄对仔猪外周血Et玫瑰花环形成率和T淋巴细胞转化率的影响。结果表明 :哺乳仔猪外周血Et玫瑰花环形成率、淋巴细胞转化率LTT(PHA、LPS刺激原)随日龄增长呈线性加大的趋势(P<0.05) ;断奶应激均使Et、LTT(PHA)、LTT(LPS)降低(P<0.05)。断奶越早 ,断奶后血液LTT(PHA/LPS)下降的幅度越大 ,恢复与哺乳猪相同水平的时间越长 ,其中14日龄断奶后1~3周 ,21、28日龄断奶后1周LTT(PHA)显著低于对照组(P<0.05) ;14日龄断奶后1~4周 ,21日龄断奶后1~3周 ,28日龄断奶后1~2周 ,35日龄断奶后1周LTT(LPS)显著低于对照组(P<0.05)。 相似文献
108.
2004年8月,江西省开始启动林业产权制度改革,用近一年的时间基本完成了试点工作,目前改革工作已在全省全面铺开.通过林改,明晰林业产权,减免税费,逐渐放活经营,规范流转,林业生产关系更加适应社会主义市场经济发展需要,提高了木材生产收益、群众造林护林积极性及山地租赁价格.但是,在新的林业生产关系下,许多配套管理措施还没有完善,森林保护管理工作出现一些新情况新问题不可避免.为保护好、管理好森林资源,需要对这些新变化、新情况、新问题进行研究,找出规范管理的新途径. 相似文献
109.
Increases in labour productivity are essential factors, as well as technical effectiveness, for the competitiveness of pig farming. However, the preferences of farmers for controlled (i.e. limited) daily working hours or available days for vacation also increase. The objective of this study was to explore how these preferences about work might be associated to specific combinations of practices or affect performance. The study was carried out by direct investigation of the stockbreeders. Data analysis used factorial analysis to identify relationships between practices, labour productivity, sow productivity and work load distribution. Results showed independence between sow productivity and labour productivity. Three independent types of preferences about work load distribution were identified: the limitation of density of daily work, the avoidance of insemination activities during the weekend and the avoidance of farrowing supervision during the weekend. These preferences about work load distribution were mainly related to weaning, oestrus detection and insemination techniques. A relationship was also seen between farrowing and cross-fostering techniques, and labour and sow productivity. Results suggest that preferences about work load distribution influence the choice of reproduction practices without influencing performance. Finally, concerning the labour productivity, it was linked with some specific techniques at farrowing but the results also indicated that it was mainly related to the size of farrowing batches. 相似文献
110.
Ellen Kaye Gehrke Ann Baldwin Patric M. Schiltz 《Journal of Equine Veterinary Science》2011,31(2):78-84
Although there has been a recent surge in using horses to treat mental and emotional human health issues, the consequences of horse-assisted interventions on the stress response of horses have not been well documented. Assessment of the autonomic nervous system and its regulation of cardiovascular function has been used as an indicator of acute and chronic stress in human beings and horses. Heart rate variability (HRV) is a noninvasive measurement that has been used to assess autonomic nervous system regulation of cardiovascular function. There is evidence to suggest that several factors including the genotype, behavior, environment, temperament, and nutritional status of the horse play a key role in the large inter-individual variations in basal HRV. The present study determined whether 24-hour HRV recordings in horses currently working in equine-assisted therapy (EAT) differ from those previously shown in Thoroughbred horses. Findings from the present study found that in contrast to previous studies in Thoroughbred horses, diurnal and nocturnal low frequency and high frequency powers were not significantly different in horses that are currently engaged in EAT. Future studies are needed to determine the short- and long-term consequences of horses participating in EAT programs. Findings from this study will provide the basis for the development of a physiological/behavioral assessment criteria to determine the consequences of EAT on the well-being of horses as well as to help EAT Centers to improve the beneficial effects of EAT in human beings. 相似文献