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91.
从动物本身、营养及环境、饲养管理等方面分析啄羽及其成因,总结出啄羽是一种行为转向的规律。凡能引导鸡啄食的物体或环境措施都能有效降低啄羽,而营养方面只要在NRC标准内都不会额外增加鸡的啄羽(色氨酸除外)。啄羽的最终解决需要各方面专家的共同努力。  相似文献   
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Some octopamine agonists were found to suppress in vitro biosynthesis of the calling pheromone of the Indian meal moth, Plodia interpunctella. Isolated pheromone-gland preparations incorporated sodium [14C]acetate at a linear rate for 3 h when incubated with the pheromone biosynthesis activating neuropeptide (PBAN). This incorporation was dependent on the dose of PBAN (up to 0.5 microM). Thin-layer chromatography of a pheromone-gland extract revealed quantitative incorporation of radioactivity into a product exhibiting the same mobility as (Z,E)-9,12-tetradecadienyl acetate, the main component of the calling pheromone of P interpunctella. Twenty-seven octopamine agonists were initially screened using a calling behaviour bioassay of female P interpunctella. Four derivatives with activity in the nanomolar range were identified which were, in order of decreasing pheromonostatic activity: 2-(2,6-diethylphenylimino)thiazolidine > 2-(2,6-diethylphenylimino)oxazolidine > 2-(2,6-dimethylphenylimino)thiazolidine > 2-(2-ethylphenylimino)oxazolidine. These compounds also showed in vitro inhibitory activity in intracellular de novo pheromone biosynthesis. The results of the present study indicate that these derivatives could provide useful information in the characterization and differentiation of octopaminergic receptor types and subtypes.  相似文献   
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This paper presents the experimental results of 9 specimens.The mainobject of this experiment is to study the aseismatic behaiour of wide-shallowcoupling beams.Several variables that exert main influence on the behaviourare considered.Also,some aspects concerning the specific design are proposed.  相似文献   
97.
试验主要研究了仔猪不同哺乳周期的行为联系。试验分别选择6头经产的民猪、长白猪及其仔猪作为观察对象,研究哺乳期间2猪种间的仔猪交流信息随时间变化的情况及品种间差异。结果表明:随着产后日龄的增加,哺乳期间一系列行为都发生了变化,仔猪间接触的行为会逐渐增加,但哺乳的第2 ̄3周又会逐渐减弱。  相似文献   
98.
The literature on the electrical properties of the body and sensitivity to steady electric current in humans and farm animals is reviewed and the problem of stray voltage is examined. Stray voltage poses a problem to animal health and protection in cattle and pigs and possibly also in other animals. Dairy cattle can perceive alternating currents exceeding 1 mA between the mouth and all four hooves. Behavioural effects in cows usually occur above 3 mA. In practice, the major influence on dairy cows appears to be behavioural. In experimental research on sensitivity to electric current, the effects studied should be related primarily to the actual current densities or electric fields in the affected tissues rather than to the total voltages applied. Under normal conditions, herdsmen are less likely to be affected by stray voltage than their animals.  相似文献   
99.
昆明动物园圈养水鹿、梅花鹿的饲养及行为观察   总被引:4,自引:0,他引:4  
对昆明动物园圈养状态下水鹿、梅花鹿的饲养管理及行为进行了观察记录和分析研究,结果表明:①水鹿、梅花鹿的日活动具有一定的节律性,1 d中有早、晚2个明显的行为活动高峰期,梅花鹿的行为活动高峰期为早(7∶30~8∶30)、晚(14∶ 30~18∶30),水鹿1 d的活动高峰为早(7∶30~8∶30)、晚(14∶30~16∶30).但检验分析结果表明,在日活动节律上水鹿与梅花鹿之间没有显著性差异(P>0.05),且水鹿的雌、雄性在日活动节律上也没有显著差异(P>0.05).②水鹿的活动时间分配为休息45.72,取食29.72、站立17.78、移动2.99,梅花鹿活动时间分配为:休息34.0 7、取食26.93、站立24.13、移动8.42;检验分析表明:两者在活动时间分配上有极显著差异(P<0.01).在活动时间分配上水鹿雌、雄体间也存在极显著差异(P<0.0 1),这些行为差异可能与其种类、性别有关.③在饲养管理上,根据鹿的不同生物学时期在饲料的组成成份上应有所侧重.  相似文献   
100.
AIM: To determine the effect of fertility control on the rate of transmission of bovine tuberculosis (Tb), caused by Mycobacterium bovis, in brushtail possums (Trichosurus vulpecula).

METHODS: At two study sites with a history of Tb infection in the resident possum population, a sample of adult male and female possums (n=50), determined by palpation to be Tb-free, was surgically sterilised by gonadectomy. A sample of untreated Tb-free male and female possums (n=54) served as controls. Each study site was trapped every 2 months over a 3-year period, and the Tb status of the individuals in the trial assessed. At the conclusion of the trial, all remaining experimental individuals were killed, necropsied and examined for characteristic lesions typical of Tb. The rate of transmission of Tb infection was estimated using the incidence of tuberculous cases in the experimental animals and comparing it between sites, sex and sterilisation treatment.

RESULTS: Sterilisation by gonadectomy resulted in a reduction in the rate of transmission of Tb in male possums by 53%, but a corresponding increase in sterilised females for reasons that are still unclear. However, this interaction was statistically weak (p=0.10). When the sexes were combined, there was no overall effect of sterilisation on the rate of transmission of Tb (p=0.43). Sterility treatment notwithstanding, there was a highly significant difference in the rate of transmission between the sexes (p=0.01), being almost one order of magnitude higher in untreated males compared with untreated females.

CONCLUSIONS: Although lacking strong statistical support, these results suggest that fertility control that targets endocrine control of fertility may provide some additional benefits for disease control over that achieved by reductions in population density, by reducing the rate of transmission of M. bovis in male possums. However, additional studies are needed to confirm the validity of these results. The large difference in the rate of transmission of M. bovis in untreated males compared with untreated females suggests that transmission of Tb among males may be an important driver of the dynamics of Tb infection in possums.  相似文献   
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