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61.
To study the effect of weaning stress on dairy buffalo calves,5 healthy calves were chosen and weaned,and the blood samples were collected at 1 day before weaning,and 1,14 and 21 days after weaning to analysis blood physiology and biochemistry indexes and immune function.The results showed that the count of white blood cell,lymphocyte,erythrocyte,monocytes and hematocrit,aspartate aminotransferase activity,blood glucose,cortisol and immunoglobulin G contents of dairy buffalo calves were no significant difference between before and after weaning treatments (P > 0.05).The count of neutrophils at 21 d after weaning were significantly lower than that of 1 d before weaning of dairy buffalo calves (P < 0.05).However,lactate dehydrogenase and alanine aminotransferase activity in weaned treatments were significantly higher than those of animals in the treatment before weaning (P < 0.05).The serum urea nitrogen of dairy buffalo calves at 21 d after weaning was significantly higher than that of 1 d before weaning (P < 0.05) and hemoglobin content at 21 d after weaning was significantly lower than that at 1 day before weaning (P < 0.05).It indicated that the physiological and immunity function of dairy buffalo calves were challenged under weaning stress.  相似文献   
62.
Arginine is one of the most important amino acids for animals,and participates in the synthesis and metabolism of many nutrients,plays a role in the development and function of the gastrointestinal tract.Intestinal barrier function is one of the most functions for intestine.The article will summarize the effect of arginine on intestinal barrier.It was explicated the influence on inteseinal immunity of Toll-like receptor.This research provided some references for further study of arginine regulation on animal production.  相似文献   
63.
The changes of cortisol, red blood cells (RBC), hemoglobin (Hb), hematocrit (Hct), heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were evaluated after a reining training session in eight Quarter Horses. All parameters were measured before exercise (T0), immediately after exercise (T1), 1 h after exercise (T2), 2 h after exercise (T3) and 24 h after exercise (T4). One‐way analysis of variance (ANOVA) for repeated measures, followed Bonferroni's post hoc test, showed a significant effect of the reining training session (P < 0.0001) on cortisol, RBC, Hb, Hct, HR, RR and RT. Simple linear regression analysis showed the positive correlation (P < 0.05) between cortisol changes and variations of studied parameters in T1, T3 and T4. Exercise‐induced cortisol concentrations reflect the physiological response of reining training, suggesting that the changes observed are useful to assess the performance in reining horses and their reining training adaptability.  相似文献   
64.
Rhinoceros populations in Africa are under severe threat as a result of surging poaching rates and risk-mitigation strategies are continuously adapted in an attempt to ensure the survival of the species. This study compared faecal glucocorticoid metabolite (fGCM) levels of two age classes of limited free-ranging female white rhinos with fGCM levels of adult free-ranging female white rhinos. Subsequently, fGCM alterations in the limited free-ranging animals were monitored following routine dehorning as a measure of the animals’ short-term physiological stress response. Baseline fGCM levels differed significantly between tested groups, with both free-ranging and limited free-ranging adult animals showing significantly higher fGCM levels compared with limited free-ranging juvenile females. In contrast, baseline fGCM levels did not differ significantly between limited free-ranging and free-ranging adult individuals. Routine dehorning procedures resulted in a short-term stress response expressed by a significant increase in fGCM levels 48 h post-dehorning, with stress steroid levels returning to pre-dehorning concentrations 72 h after the procedure.  相似文献   
65.
66.
According to the investigations of urban barrier free facilities, there have been lots of progresses in constructions of barrier free in cities recently. But there are no systematic barrier free facilities in these cities, which would restrict the function and effect of urban barrier free facilities for the handicapped and the elder. This paper puts forward that there should be a development from the urban barrier free facilities to the urban barrier free environment. There are two parts in the barrier free environment,that is the hardy environment and soft environment. Finally,an in-series connection two-core model of barrier free environment has been designed and discussed.  相似文献   
67.
This paper analyses the thermal moist characteristics of the hull layer beside an air layer at lower temperature in an envelope for a cold storage and presents a new method of waterproof by air layer. With test data from engineering practice, the theory on the barrier of self moisture proof at the surface sublayer of the hull layer in an attic on a cold storage is proven. The dried zone about three phase point is confirmed. It is a new knowledge for thermophysics on thermal design of a cold storage with an optimum thermal performance.  相似文献   
68.
棉花调亏灌溉的生态生理效应   总被引:6,自引:1,他引:6  
在人工控制试验条件下 ,采用子母盆栽土培法 ,以棉花为试验材料进行了调亏灌溉试验研究。结果表明 ,棉花调亏灌溉是可行的 ,可以实现节水、高产和高效的目标。适时适度的水分调亏显著抑制蒸腾速率 ,而光合速率下降不明显 ,复水后光合速率又具有超补偿效应 ,光合产物具有超补偿积累 ,且有利于向棉铃运转与分配 ;抑制营养生长 ,促进生殖生长。棉花调亏灌溉的适宜指标是 :苗期轻、中度调亏 ,0~ 40 cm土层湿度控制下限为田间持水量的6 0 %或 5 0 %;蕾期轻度调亏 ,0~ 40 cm土层湿度控制下限为 6 0 %;花铃期不宜调亏 ,应保证充足供水 ,0~ 40 cm土层湿度应不低于 75 %;吐絮期可中度调亏 ,0~ 40 cm土层湿度可控制在 5 0 %~ 5 5 %。  相似文献   
69.
大型泵站拦污清污方案选择   总被引:1,自引:1,他引:1  
介绍了泵站常用的拦污、清污方式。结合谏壁抽水站的具体情况,给出了斜式拦污栅的结构设计、布置方式;对抓斗式、回转式两种形式清污装置的方案进行了比较,结论是:抓斗式清污机造价低、施工容易、维修方便、可靠性好、具有较高综合利用价值,更适合污物较多的泵站。  相似文献   
70.
添加纳米粒子的塑料包装材料在杨梅保鲜中的作用   总被引:3,自引:0,他引:3  
纳米技术应用在杨梅保鲜包装上是一个新的尝试,它采用了交互性实验设计方案,将银纳米材料添加进塑料制成包装材料,可观测其保鲜效果.结果表明,纳米塑料包装材料和纳米奇冰石在提高杨梅好果率和延长货架期方面有正面效果;同时,在抑制VC分解方面具有一定的作用.  相似文献   
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