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821.
水冷式猪床冬季保温措施对妊娠母猪小群饲养的影响 总被引:2,自引:2,他引:0
为探讨在冬季低温条件下水冷式猪床保温措施对妊娠母猪小群饲养的影响,试验选用16头配种4周左右的母猪,随机分为对照组和试验组,每组各2圈栏,每圈栏4头。在试验组猪床单元两端设有门帘来提高猪床内环境温度,测试各组环境温度及观察母猪行为。结果表明:单个猪床单元内1头猪躺卧时,试验组单元内温度比对照组和舍内温度平均分别高3.2和6.9℃,当试验组和对照组舍内温度分别高于11和12℃,均未出现2头猪挤在1个单元内躺卧。试验组与对照组相比,母猪每天平均躺卧时间(18.6和17.8h)和饮水次数(18.5和23.3)差异显著(P<0.05),咬链次数(14.0和19.0)差异极显著(P<0.01)。对照组在猪床单元内排便和排尿分别占总次数的1.8%和12.1%,而试验组分别为0和3.2%。研究结果表明,猪床门帘可提高母猪躺卧区的局部温度和减少母猪的刻板行为。 相似文献
822.
823.
刘占郇 《湖南农业大学学报(自然科学版)》1990,(1)
本文通过对畜禽骨骼标本的取材、脱脂、安装造型等工艺的研究,提出了一套制作骨骼标本的新工艺,在骨骼脱脂、标本安装造型方法上作了较大的改进,实践证明新工艺是可行的。 相似文献
824.
1990的3-8月,对胡陈港水库浮游生物的种类和数量进行了调查。结果表明,胡陈港水库的浮游植物共52属。其中,蓝藻门7属,绿藻门19属,硅藻门17属,裸藻门3属,甲藻门4属,金藻门1属,黄藻门1属。其年平均数为130.39×14^4个/L,最高峰出现在7月份,为162.86×10^4个/L。浮游动物30属。其中,原生动物7属,轮虫12属,枝角类2属,桡足类9属。其年平均数5440个/L,以轮虫占绝 相似文献
825.
826.
827.
Risk factors for nuisance barking in dogs 总被引:1,自引:1,他引:0
Objective To determine the key variables related to the environment, animal and owner that influence nuisance barking by dogs in a city with a subtropical climate.
Design and Population A case–control survey of dog owners in Brisbane, Queensland, was conducted using a questionnaire investigating key variables connected to nuisance barking. Owners of dogs exhibiting nuisance barking were obtained from a list of dogs being treated in a Brisbane behaviour clinic, and those of control dogs were selected from a telephone directory.
Results Univariate analysis showed that animal, owner and environmental factors all potentially influence the occurrence of nuisance barking. Multivariate analysis identified the following factors, with the relevant odds ratios (OR) as significant: age of the dog (young dog vs old dog, OR 11.2); multiple dogs in the household vs single (OR 5.6); origin of the dog (home bred vs obtained from breeder or friend, OR 4.0); type of dog, (herding vs other types, OR 3.2) and dog with access to the home vs dog without access (OR 2.5).
Conclusion The greatest risk for nuisance barking occurs with a young dog of the herding type that is home bred and with access to the house in a multiple dog household. 相似文献
Design and Population A case–control survey of dog owners in Brisbane, Queensland, was conducted using a questionnaire investigating key variables connected to nuisance barking. Owners of dogs exhibiting nuisance barking were obtained from a list of dogs being treated in a Brisbane behaviour clinic, and those of control dogs were selected from a telephone directory.
Results Univariate analysis showed that animal, owner and environmental factors all potentially influence the occurrence of nuisance barking. Multivariate analysis identified the following factors, with the relevant odds ratios (OR) as significant: age of the dog (young dog vs old dog, OR 11.2); multiple dogs in the household vs single (OR 5.6); origin of the dog (home bred vs obtained from breeder or friend, OR 4.0); type of dog, (herding vs other types, OR 3.2) and dog with access to the home vs dog without access (OR 2.5).
Conclusion The greatest risk for nuisance barking occurs with a young dog of the herding type that is home bred and with access to the house in a multiple dog household. 相似文献
828.
Kasamatsu M Kawauchi R Tsunokawa M Ueda K Uchida E Oikawa S Higuchi H Kawajiri T Uchida S Nagahata H 《Research in veterinary science》2009,86(2):216-222
Concentrations of serum lipid components, lipid peroxide (LPO) and α-tocopherol and electrophoretic patterns of lipoproteins in serum samples obtained from captive marine mammals and terrestrial mammals were compared. Serum concentrations of total cholesterol, free fatty acid, and phospholipid in fish-eating animals were significantly higher than those in manatees and cows. Serum LPO and α-tocopherol concentrations in the fish-eating animals were also significantly higher than those in manatees, cows and dogs. Different patterns of densitometric scans of low density lipoprotein (LDL) and a significantly lower percentage of LDL were demonstrated in the dolphins compared with the seals, cow and dogs. The concentration of LPO was significantly correlated with triglyceride and phospholipid concentrations in serum from the dolphins. These results suggest that triglyceride and phospholipid are susceptible to oxidative reaction in fish-eating animals. Evaluation of serum lipids, LPO and α-tocopherol concentrations is needed for nutritional husbandry for fish-eating animals. 相似文献
829.
The aminoglycoside apramycin has been used widely in animal production in China since 1999. This study was aimed to investigate the resistance pattern of apramycin-resistant Escherichia coli isolated from farm animals and farm workers in northeastern of China during 2004–2007 and to determine whether resistance to apramycin was mediated by plasmid containing the aac(3)-IV gene and the mode for the transfer of genetic information between bacteria of farm animals and farm workers. Thirty six E. coli isolates of swine, chicken, and human origins, chosen randomly from 318 apramycin-resistant E. coli isolates of six farms in northeastern of China during 2004–2007, were multi-resistant and carried the aac(3)-IV gene encoding resistance to apramycin. Conjugation experiments demonstrated that in all 36 cases, the gene encoding resistance to apramycin was borne on a mobilisable plasmid. Homology analysis of the cloned aac(3)-IV gene with the sequence (accession no. X01385) in GenBank showed 99.3% identity at a nucleotide level, but only with a deletion of guanosine in position 813 of the gene in all 36 cases. The results indicted that resistance to apramycin in these isolates was closely related to aac(3)-IV gene. Therefore, the multi-resistance of E. coli could complicate therapeutic practices for enteric infections in both farm animals and human. 相似文献
830.