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11.
季节对山羊反刍行为的影响   总被引:2,自引:0,他引:2  
对16只中卫山羊母羊的青草期和枯草期反刍行为进行观察表明,山羊在青草期,每天(24hrs)有10个反刍周期,反刍持续总时间为304.2分,共反刍425.3次,每个食丸在口腔中咀嚼43.0秒,共咀嚼46.4次,在枯草期上述指标分别为11个,420.0分,472.0次,53.4秒和59.6次,季节对山羊反刍行为的影响,本质上决定于羊采食牧草的品质和数量,优质牧草(青草期)能够缩短反刍持续总时间(P〉0  相似文献   
12.
The purpose of this study was to determine the optimal time for ovulation induction and artificial insemination (AI) based on the relationship between estrous behavior and ovulation in jennies. Thirty-two jennies were teased by one jackass for 1 hour per day during 46 days and estrous behaviors were recorded, while the follicular development and ovulation was examined by ultrasound. Furthermore, another 31 jennies were teased by one jackass as the teasing group (group T), which were injected with Deslorelin at 2 and 4 days after the onset of estrus, and AI was performed at 8 hours after each injection. Moreover, Ultrasound was performed on the follicle development of 23 jennies as the ultrasonography group (group U). Injection with Deslorelin when the follicle diameter ≥ 30 mm, and AI was performed at 8 hours later. The results showed that mouth clapping was the specific estrous behavior of jennies and indicated the beginning of estrus. The mean time for jennies to develop dominant follicles (≥30 mm) after the onset of estrus was 3.5 ± 1.3 days, and the mean time between the onset of estrus and ovulation was 5.1 ± 1.5 days. Estrous behaviors ended 0.5 ± 1.2 days after ovulation. After AI, there were no significant differences in ovulation (96.8% vs. 91.3%) and conception rates (40.0% vs. 38.1%) between group T and U. The optimal breeding time of jennies can be determined by jackass teasing and hastening ovulation by Deslorelin injection.  相似文献   
13.
Reproductive phenology is an important trait subjected to natural selection. Current horses in America belong to the Palearctic original populations after being introduced by European colonizers. Photoperiod variation is the main environmental factor for the adjustment of reproductive timing in horses, but is absent in equatorial areas. Here we hypothesize that seasonality of green‐grass availability may influence breeding phenology in equatorial regions. We used data of 929 services to mares from 2006 to 2011 in a thoroughbred equine exploitation in Ecuador that experienced strong grass seasonality. Actual births could not be used to infer natural phenology because they were influenced by management decisions. Instead, we used variations in the probability of pregnancy after a service as a measure of the natural tendency of mares to show breeding phenology. We found that although managers tended to schedule pregnancies in two periods within the year, mares were more prone to become pregnant after the increase in grass greenness that takes place at the beginning of the year (February). Our finding has potential applications to improve the success of services and the welfare of animals, by providing green‐grass stimuli in the appropriate season.  相似文献   
14.
傅文源 《野生动物》2009,30(5):231-233,244
在人工围栏的自然生境中,采用扫描取样法和焦点取样法对梅花山自然保护区"中国虎园"内13只华南虎(其中雌虎7只,雄虎6只)的采食行为进行了初步研究。结果表明,华南虎对采食时间、频率等受季节、生理状态、竞争等因素影响;采食行为在人工哺乳和自然哺乳成活的个体之间差异显著。  相似文献   
15.
Survival and successful reproduction require animals to make critical decisions amidst a naturally dynamic environmental and social background (i.e. “context”). However, human activities have pervasively, and rapidly, extended contextual variation into evolutionarily novel territory, potentially rendering evolved animal decision‐making mechanisms and strategies maladaptive. We suggest that explicitly focusing on animal decision‐making (ADM), by integrating and applying findings from studies of sensory ecology, cognitive psychology, behavioral economics and eco‐evolutionary strategies, may enhance our understanding of, and our ability to predict how, human‐driven changes in the environment and population demography will influence animal populations. Fundamentally, the decisions animals make involve evolved mechanisms, and behaviors emerge from the combined action of sensory integration, cognitive mechanisms and strategic rules of thumb, and any of these processes may have a disproportionate influence on behavior. Although there is extensive literature exploring ADM, it generally reflects a canalized, discipline‐specific approach that lacks a unified conceptual framework. As a result, there has been limited application of ADM theory and research findings into predictive models that can enhance management outcomes, even though it is likely that the relative resilience of species to rapid environmental change is fundamentally a result of how ADM is linked to contextual variation. Here, we focus on how context influences ADM, and highlight ideas and results that may be most applicable to conservation biology.  相似文献   
16.
17.
This paper reflects the results of a short experiment conducted in parallel with a larger trial which aimed to test the assumption that ‘consumption of feed by broiler chickens during periods of darkness is largely negligible’. To that effect, on d 31, feeders of birds raised under intermittent lighting (IL), i.e. 1 h of light [1L]:3 h of dark (3D):1L:3D:1L:3D:1L:3D:2L:6D, were weighed at the onset and at the end of each period of darkness (or scotoperiod). Moreover, in order to compare the feeding behavior of IL birds with that of broilers raised under continuous lighting (CL, i.e. 18L:6D), their feeders were weighed in parallel and at the same time points. On d 31, feed intake of IL birds during scotoperiods represented 45% of their 24 h feed intake. Both CL and IL birds presented anticipatory feed intake prior to the long nocturnal period of darkness (6D), as well as higher feed intake right at the onset of lighting at 06:00. Feed intake of CL birds during the 6D nocturnal scotoperiod was negligible at around 2% of their total feed intake. Intermittent lighting birds exhibited excitement at the start of each hour-length scotoperiod and, within that time, ingested around 2.5 times the amount of feed ingested by CL birds. Although short, this study revealed several interesting observations which might be worth further exploring in a larger, lengthier, behavior-focused experiment. Amongst other factors, it might be interesting to understand whether the high feed intake observed during scotoperiods for IL birds in reflective of the whole flock or rather a coping mechanism developed mainly by hierarchically lower-ranking birds to achieve their daily feed intakes requirements.  相似文献   
18.
几种禾草的开花习性   总被引:5,自引:0,他引:5  
张新全  杜逸 《草业科学》1994,11(3):42-45
研究11份禾草种质料的开花习性表明:稗草,长叶雀稗及草芦的小花开放顺序,通常由顶部向基部开放,而庐山草芦及鸭茅则表现为由中上部位向上,下两端开放。单个花序开花持续时间在7-32天。除草芦外,其余各属饲草的不同草种间小花开部特点相似。3种稗草有部分不花闭颖返粉结实。庐山草芦一日开花高峰在下午14-15时,其余均在上午,多数在8-10时。  相似文献   
19.
白头鹤是长江中下游的大型越冬水鸟,安徽升金湖是其在国内主要的越冬地之一。近年来,由于生境退化,越冬种群的数量在萎缩,种群的越冬生态研究十分必要。2007年10月~2008年4月,我们在升金湖对白头鹤的主要分布地点进行了调查,并对集群情况进行了观察。升金湖白头鹤觅食地主要分布于湖区外围的稻田,夜栖于上湖核心区内。整个越冬期,白头鹤大部分以5只以上的群类型觅食,以家庭集群活动仅占越冬集群数的29.14%。随着越冬期的变化,集群大小发生改变:越冬前期,越冬鹤以家族群活动频率最高,占集群的35.64%,30~49只集群频率最低,仅为6.38%;越冬中期,家庭集群及5~9只集群频率相对于越冬前期减少,10只以上集群频率增加;越冬后期,以≥50只以上集群频率最高,占28.77%。此外,我们还观察到1对成年鹤占有一定面积的稻田并积极保护,表现领域行为。  相似文献   
20.
通过对金融生态主体:政府、金融缉织、非及金融组织的行为倾向进行分析,在心里学与利益制衡范畴解释其行为动机,和这一动态演进过程造成的结果。然后,模拟金融生态主体博弈过程,借助其在社会范围之内的相互联系、相互影响、共同作用,反过来影响和形成了短期社会规则,并影响金融生态的长期构建。  相似文献   
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