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171.
172.
采用行为学方法研究大棚饲养条件下风扇降温和水帘降温以及舍饲、35日龄开放运动场、70日龄开放运动场对黄羽肉鸡采食、饮水、修饰、站立、运动、觅食、攻击、休息、沙浴,栖架10种行为的影响。结果表明:(1)水帘降温组鸡群采食和修饰行为的百分比极显著高于风扇降温组(P〈0.01);而饮水、站立和觅食行为的百分比则极显著低于风扇降温组(P〈0.01);沙浴行为百分比也显著低于风扇降温组(P〈0.05),其他的行为变化差异不显著(P>0.05)。(2)放养措施可以极显著增加鸡群的采食、饮水、修饰、运动、觅食、休息以及沙浴等7种行为的百分比(P〈0.01),极显著降低鸡群的栖架行为及站立行为的百分比(P〈0.01);其他的行为变化差异不显著(P>0.05)。表明不同降温措施和不同时间放养措施显著影响肉鸡采食、饮水、站立、修饰、觅食和沙浴行为百分比,上述6种行为指标可作为评价黄羽肉鸡福利养殖水平的参考指标。  相似文献   
173.
150 Hz矩形波断续音对褐菖鲉音响驯化的试验研究   总被引:1,自引:0,他引:1  
采用150 Hz矩形波断续音,对体质量为32.3~65.7 g的褐菖鲉Sebastisous marmoratus幼鱼进行了音响驯化试验。结果表明:驯化3d后,试验组褐菖鲉对声音开始产生趋向性;试验组鱼的反应时间在驯化第2~5天时,虽然明显高于对照组(P<0.05),但总体呈下降趋势,驯化第9天时与对照组接近(P>0.05),驯化第10天~第25天时总体维持在一个较低水平,与对照组无显著性差异(P>0.05),驯化第17天时反应时间达到最低值2 s;试验组鱼的聚集时间在驯化第2天~第6天时下降明显,之后随着驯化时间的延长,聚集时间下降趋势趋缓,驯化第12天时接近对照组( P>0.05),并从第14天开始低于对照组,驯化第14天~第16天、第18天~第21天、第23天~第25天时均显著低于对照组(P<0.05),驯化第19天时聚集时间降到最低值26 s;试验组鱼的聚集率总体呈上升趋势,驯化第20天时聚集率达到最高值86.7%,而对照组则时高时低,并且从第3天开始显著低于试验组( P<0.05);在试验的后5 d投放人工鱼碓后,放音时仍然能将试验组(不投放饵料)大部分褐菖鲉从鱼礁中引出,聚集率最低为75.0%,与对照组有极显著性差异(P<0.01)。研究表明,150 Hz矩形波断续音能够对褐菖鲉有很好的诱集作用,而且能明显吸引聚集在人工鱼礁中的褐菖鲉。  相似文献   
174.
随着经济社会的发展,消费问题日益突出。即使是在一些县、乡、村,也存在着农村居民的消费行为日益受到环境变化的影响问题。本文基于对吉林省农村居民消费行为实际调查研究基础上,通过对数据的分析整理,得出相应结论,并分析影响吉林省农村居民消费行为的影响因素,最后提出对策建议,为实现吉林省农村建设跨越式发展提供理论依据。  相似文献   
175.
AIM:To evaluate the effect of chronic alcohol intake on the histopathological changes of the liver and to determine the contribution of epithelial-mesenchymal transition (EMT) to hepatic fibrogenesis. METHODS:Thirty male C57BL/6 mice were randomly divided into 3 groups as following: the mice in control group was given (ig) water; the mice in low-dose alcohol group (2.0 g·kg -1·d -1) and high-dose alcohol group (4.0 g·kg -1·d -1) were given (ig) alcohol for 5 months. Alcohol-induced histopathological changes of the liver or development of hepatic fibrosis were evaluated using the histological methods with HE and Masson trichrome staining. The apoptosis of the liver was detected by TUNEL fluorometric staining (counterstained with DAPI). The activity of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) was measured by an automated biochemical analyzer. The expression of fibroblast-specific protein 1 (FSP-1), α-smooth muscle actin (α-SMA) and E-cadherin in the hepatic tissues was detected by immunofluorescence examination. The protein levels of E-cadherin, α-SMA, FSP-1, transforming growth factor β 1 (TGF-β 1) and hypoxia-inducible factor 1α (HIF-1α) were analyzed by Western blotting. RESULTS:Compared with control, the activity of serum ALT and AST, and apoptotic index of liver tissues were increased in the mice treated with alcohol for 5 months. The histopathological changes of the livers in the mice of low-dose alcohol group included steatosis and mild liver fibrosis, while severe liver fibrosis was observed in the high-dose alcohol-treated mice. Chronic alcohol consumption induced the increase in malondialdehyde (MDA) level, and the decreases in the activity of superoxide dismutase (SOD) and catalase (CAT) in the livers. It also reduced E-cadherin expression and increased α-SMA expression. FSP-1 immunostaining and albumn immunostaining positive cells were co-localized in the hepatocytes of low-dose alcohol group, but only FSP-1 positive hepatocytes were observed in high-dose alcohol group. Chronic alcohol consumption decreased E-cadherin expression and increased α-SMA, FSP-1, TGF-β 1 and HIF-1α expression in a dose-dependent manner, but the HIF-1α expression was not altered between the 2 alcohol-treated groups. CONCLUSION:Chronic alcohol intake induces the progression of hepatic fibrosis. Some fibroblasts derive from hepatocytes in liver fibrosis via EMT. The underlying mechanism is associated with the changes of the redox state, and increased TGF-β 1 generation and HIF-1α expression.  相似文献   
176.
AIM:To investigate the effects of siRNA targeting integrin-linked kinase (ILK) on the expression of glycogen synthase kinase 3β (GSK-3β) and β-catenin during epithelial-mesenchymal transition (EMT) in human kidney proximal tubular epithelial cell line HKC induced by high glucose. METHODS:HKC cells were divided into 4 groups:normal glucose (NG) group, high glucose (HG) group, HG+HK (a vector containing the non-specific siRNA designed as negative control) group and HG+ILK siRNA group. The inverted fluorescence microscope was used to examine the expression of green fluorescent protein (GFP). The expression of ILK at mRNA and protein levels was detected by RT-PCR and Western blotting. The expression of p-GSK-3β and β-catenin was observed by immunocytochemical staining. The protein expression of total GSK-3β, p-GSK-3β, nuclear β-catenin, total β-catenin, E-cadherin and α-smooth muscle actin (α-SMA) was measured by Western blotting. RESULTS:GFP was observed in HKC cells, indicating that the transfection was successful. Both the protein and mRNA of ILK were down-regulated in HG+ILK siRNA group compared with HG group and HG+HK group, but still higher than those in NG group. Silencing of ILK down-regulated the expression of p-GSK-3β and nuclear β-catenin. No difference of total GSK-3β or total β-catenin was observed among the 4 groups. CONCLUSION:These data support a functional role of ILK, GSK-3β and β-catenin in tubular EMT induced by high glucose. ILK may promote tubular EMT by regulating the activity of GSK-3β and β-catenin, the downstream effectors of the Wnt/β-catenin pathway.  相似文献   
177.
朱清澄 《水产学报》2003,27(5):499-503
尼罗罗非鱼(OreochromisniloticaL.)属热带性鱼类,为我国1978年从国外引进的优良海淡水养殖对象,具有食性杂、生长速度快、肉质鲜美、经济价值高等优点[1]。目前已在我国数个省、市开展养殖。尼罗罗非鱼性喜群游,其最适生长水温为24~32℃,水温降至14℃时,活动迟缓,停止摄食,水温降至12℃以下时便逐渐死亡[2]。因此,在我国北方地区养殖的尼罗罗非鱼,一般在严冬前开始进行捕捞。水温达到20℃以上时,雄鱼会在池边或者池底挖洞,当遇到外界刺激或拉网捕捞受惊后,便潜入洞中或软泥中。尼罗罗非鱼的这一行为习性给捕捞造成很大困难,因此各地一般…  相似文献   
178.
The present study examined daytime behavior patterns of 19 captive tigers (Panthera tigris tigris) housed in Nandankanan Zoological Park, Odisha, India. Behavioral observations of 1254 hours were analyzed for target behaviors using instantaneous sampling and 1-minute sample periods. We found that these captive tigers spent about 23% of the daytime exhibiting stereotypic behavior, that is, pacing, with a biphasic peak at 10:00 to 11:00 am and 16:00 to 17:00 pm. The incidence of stereotypic pacing behavior appears high, warranting further investigation of the cause of this stereotypic behavior and whether an effect of behavioral enrichment is required for a better understanding of welfare implications on the animals.  相似文献   
179.
In equines, calls given by foals or mothers when they are seeking contact with each other or by stallions seeking contact with other group members could be classified as affiliative or separation calls when a reunion follows the vocalizations. To investigate how domestication can affect the characteristics of vocalizations produced by equines, separation calls produced by Przewalski's (Przw) horses and Mongolian domestic horses (MDH) living in the same habitat were recorded, spectrally analyzed, and compared. Species-specific acoustic differences were found in the separation vocalizations of mares and foals. In particular, the second and third formants of the calls emitted by Przw mothers were significantly higher in frequency than those emitted by Mongolian domestic mothers, whereas the same acoustical variables were significantly lower in Przw foals than Mongolian domestic foals. Second and third formants have a significant effect on discriminating separation calls emitted by mares and foals from these different equine species. With the exception of the duration of the call, no significant species-specific differences in acoustic parameters were observed in separation calls emitted by stallions. Bioacoustic analysis can discriminate 2 different species that can be affected by their environment, evolution, and social organization.  相似文献   
180.
Calving is an intrinsically risky process that can cause welfare and economic problems. The objective of this study was to assess the effect of the nonsteroidal anti-inflammatory drug meloxicam on various physiological and behavioral measures which can be related to pain in cattle. Sixty Friesian dairy cows from first to sixth parity were studied around calving and were randomly allocated into 2 homogeneous groups relative to parity and treated with either meloxicam or a placebo after calving. Treatments were administered on average 3.4 hours after calving, within a maximum of 6 hours. Calf positions at calving and calving assistance (unassisted or easy manual pull) were recorded. Milk production, rectal temperature, and activity (calculated as the number of steps per hour) were measured on each cow. From a subsample of 20 cows, haptoglobin (Hp) and serum amyloid A (SAA) concentrations were also obtained. The following behaviors were observed on video recordings: posture, changing posture, location of cow in pen, feeding, and tail up behaviors 2 days before and after calving. Statistical analysis was carried out with the SAS software using MIXED or GENMOD procedures. Most variables showed a parity and/or time effect around calving. This study did not demonstrate any significant effect of meloxicam on milk production or on acute phase responses of Hp and SAA. However, postcalving activity was significantly increased in meloxicam-treated heifers.  相似文献   
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