高原鼢鼠繁殖期和非鳘殖期的行为比较

本文在室内饲养条件下对高原鼢鼠非繁殖期和繁殖期的行为进行了观察,定性,定量地对１６种行为进行了描述和分析。结果表明,这两个时期的行为基本没有变化,但行为发生的频次和持续时间有极大的不同。各种行为的时间分配在２４小时内及其在两个不同时期之间均有一定的差异,而每小时内动物的主要行为表现为睡眠和休息,移动,取食,挖掘,相互接触。     

笼养褐马鸡繁殖期与非繁殖期行为观察与比较

2014年4—10月,利用焦点个体取样法与连续记录法对北京市野生动物救护繁育中心饲养的褐马鸡Crossoptilon mantchuricum繁殖期以及非繁殖期的行为时间分配和活动节律进行了研究。统计了不同性别与不同季节的行为时间分配差异。在繁殖期,雌性褐马鸡的取食时间大于雄性,而雄性褐马鸡的移动、警戒行为时间大于雌性。在非繁殖期,雌雄褐马鸡行为差异变小,但雄性褐马鸡的警戒行为仍然较多。     

杂色山雀繁殖期与非繁殖期食物组成及利用

食物资源是动物赖以生存的重要物质基础和能量来源。研究鸟类不同时期的食物选择和利用对于了解该物种取食行为的可塑性和生态适应性将具有重要意义。本文于2012年4月至2013年10月,通过取食行为观察、育雏分析和投食实验来研究杂色山雀(Parus varius)繁殖期与非繁殖的食物组成及利用的差别。结果发现,杂色山雀繁殖期与非繁殖期存在显著的食物差别,繁殖期完全取食动物性食物,而非繁殖期则以植物性食物为主,兼食少量昆虫。繁殖期成鸟取食的食物主要为鳞翅目、蜘蛛目、鞘翅目、双翅目以及少量的直翅目、异翅亚目以及膜翅目动物,育雏的食物资源主要为鳞翅目幼虫(67.86%),其次为蜘蛛目、鳞翅目成虫、膜翅目以及鞘翅目幼虫和少量直翅目,但与成鸟的食物存在显著区别,特别是鳞翅目幼虫的比例极高。非繁殖期的食物主要以植物种子(48.91%)和浆果为主(51.09%),其中,浆果的比例较高,对16种潜在食物资源的取食选择也证明对浆果类食物具有较明显的偏爱。杂色山雀不同时期的食物差别和食性的可塑性可能是由于食物供给和能量需求的季节性变化造成的,但对于自然生境中各种食物资源丰富度的季节性变化,及对杂色山雀取食选择的影响还需进一步研究。     

大鵟繁殖期的行为及时间分配

2015年4～9月,采用焦点动物取样法,通过人工观察及监控设备记录,在青海省祁连县研究了2窝在人工巢中繁殖的大(鵟)(Buteo hemilasius)行为.构建了大(鵟)亲鸟及雏鸟在繁殖期的行为谱,将亲鸟繁殖期内的行为划分为12项30种,将雏鸟的行为划分为9项25种.研究发现,大(鵟)繁殖期开始于4月中下旬,持续至8月中旬结束,平均(112.0±2.0)d(n=2);将繁殖期划分为孵卵前期、孵卵期、育雏期及雏鸟成熟期.利用单因素方差分析(One-way ANOVA)比对了雌雄亲鸟之间,以及不同时期间亲鸟、雏鸟的行为时间分配.结果显示,(1)雌雄大(鵟)之间的行为时间分配在孵卵前期及孵卵期差异不显著(P＞0.05),在育雏期及雏鸟成熟期差异显著(P＜0.05).在这两个时期,雌性栖停行为所占比例显著高于雄性(P＜0.01),而捕食行为占比显著低于雄性(P＜ 0.01).(2)雌性大(鵟)行为时间分配在不同时期均变化显著(P＜ 0.05),雄性大(鵟)行为时间分配在育雏期与雏鸟成熟期间差异不显著,其余各个时期间差异显著(P＜ 0.05).(3)大(鵟)雏鸟行为时间分配在育雏期与成熟期之间差异显著(P＜0.05).     

卧龙血雉繁殖期行为特征分析

1 995年 4～ 6月在四川卧龙自然保护区五一棚地区 ,采用无线电追踪技术结合野外行为观察 ,对血雉繁殖期行为特征进行了研究。结果表明 ,繁殖前期雄鸟在警戒行为的频次及持续时间上均显著地高于雌鸟 (T test,频次 ,t=-4 73 ,P <0 0 1 ;时间 ,t=-2 80 ,P <0 0 5 ) ;孵卵期 ,雄鸟在警戒行为的总持续时间上显著地高于雌鸟 (T test,t=-4 75 ,P <0 0 1 ) ,雌鸟在取食行为的总持续时间上显著地高于雄鸟 (T test,t=3 41 ,P <0 0 5 ) ;对雌雄个体行为同时进行观察的结果表明 ,雌鸟维持行为的时间与雄鸟警戒行为的时间显著正相关 (Y =49 68+0 2 693X ,r=0 71 79,P =0 0 0 2 6)。繁殖前期和孵卵期雄鸟的警戒行为可以提高雌鸟用于取食、理羽、沙浴的时间 ,而减少用于警戒的时间     

珠颈斑鸠繁殖期占据领域鸣声特征及行为

2003年4～6月,在四川省南充市通过野外观察、录音、室内计算机处理及声谱分析对珠颈斑鸠繁殖期占据领域鸣声特征及行为做了研究。结果表明：珠颈斑鸠有一般占据和召唤配偶共同占据两类鸣声,两类鸣声雌雄不同,但均由3音节组成;其鸣唱具有应答性,且每次在各栖位点的鸣唱顺序大致相同;日鸣唱频次变化大,具3个高峰期;繁殖各时期鸣唱频次变化亦大。     

圈养普氏野马繁殖期的昼间行为时间分配

2011年4月~8月,在新疆野马繁育中心采用目标动物取样法,研究了圈养普氏野马(Equus ferus przewalskii)繁殖期昼间行为时间分配。结果表明:(1)雌雄普氏野马繁殖期采食、饮水和站立行为差异不显著(P0.05),而休息、运动、修饰和其他行为均表现出显著性差异(P0.05)。其中,雄马的休息时间、修饰时间显著低于雌马,运动时间和其他行为时间显著高于雌马。(2)雌雄个体繁殖期除运动、修饰和其他行为节律存在显著差异外(P0.05),其余行为节律则表现出一定的同步性。(3)雌雄野马繁殖期内昼间交配次数比较少,且同一家族群内雌马各自参与交配的日期基本不会重叠,同一天内,雄马与群内两匹以上雌马均有交配的现象十分罕见。     

东方白鹳繁殖期行为时间分配及日节律

2009年3—6月,采用扫描取样法对在黄河三角洲国家级自然保护区内繁殖成功的4对东方白鹳的行为活动进行了观察,同时对东方白鹳在繁殖期的行为时间分配和日节律进行了研究。结果表明:繁殖期各行为时间所占比例依次是繁殖22.17%±21.69%(其中孵化19.75%±20.71%,晾卵1.31%±2.16%,育幼1.00%±1.01%,交配0.11%±0.32%),静栖19.09%±13.94%,修巢6.40%±5.92%,警戒3.94%±4.88%,理羽3.11%±2.31%,其他行为45.27%±11.08%;在繁殖不同时期各行为差异显著(P0.01)。东方白鹳在繁殖期不同阶段行为活动存在一定节律,并且不同阶段日节律明显不同。此外,温度与晾卵(r=0.810,P0.01)、孵化(r=-0.518,P0.01)行为显著相关;车辆数与警戒(r=0.745,P0.01)、静栖(r=0.612,P0.01)行为显著相关。     

麝鼠前列腺在繁殖期和非繁殖期转录组差异分析

麝鼠(Ondatra zibethicus L.)是季节性繁殖动物。成年雄性麝鼠在尿生殖孔上方肌肉与背皮之间有一对香腺,在繁殖期能分泌麝鼠香。与其他鼠类相比,麝鼠在繁殖期时前列腺—精囊腺组织极其发达。研究发现,经腹腔注射麝鼠香后,能够明显促进雄性小鼠的前列腺—精囊腺发育,表明两者之间可能存在一定的相关性。本研究利用RNA-seq技术对麝鼠繁殖期和非繁殖期的前列腺样品进行了转录组测序,对差异表达的基因进行GO分析和KEGG通路分析。结果显示,共筛选出1629个显著差异表达基因,涉及多种信号转导和能量代谢相关基因,其中OBP2、Bcl-2家族和肿瘤坏死因子受体超家族成员的差异表达提示麝鼠前列腺发育受多种机制调控,由香腺分泌的麝鼠香可能参与了前列腺的发育调节。     

内蒙古达赉湖地区蒙原羚繁殖期及其前后昼间行为时间分配及能量平衡策略

2007年11月、12月和2008年3月,在内蒙古达赉湖地区,采用扫描取样法对雌雄蒙原羚繁殖期及其前后昼间行为时间分配进行了研究。 研究表明：（1）繁殖期前、繁殖期和繁殖期后,雌性蒙原羚采食时间,占昼间活动时间的比例分别为（44.9±3.8）%、（43.5±4.0）% 和 (46.2±3.1)%;卧息时间,占昼间活动时间的比例分别 为（32.3±4.8）%、（29.2±2.9）% 和 (28.0±4.8)%;雌性蒙原羚在繁殖期及其前后采食、移动和卧息的行为时间分配差异不显著（P>0.05）,站立、繁殖、“其他”行为时间分配差异性显著（P<0.05）。（2）繁殖期前、繁殖期和繁殖期后, 雄性蒙原羚采食时间,占昼间活动时间的比例分别为 (52.6±3.8)%、(17.5±2.8)% 和 (29.8±4.8)%;卧息时间,占昼间活动时间的比例分别为 (13.4±6.4)%、(24.2±4.1)% 和 (44.2±4.7)%。雄性蒙原羚在繁殖期及其前后采食、卧息、站立、移动、繁殖、“其他”时间分配均有显著差异（P<0.05）。动物采食卧息的行为时间分配反映动物的能量平衡策略。雌性蒙原羚的时间分配表明,雌性蒙原羚的能量平衡策略在繁殖期前、繁殖期和繁殖期后没有发生显著变化,均为能量摄入最优化策略,尽可能多的时间分配在采食上;雄性蒙原羚的时间分配表明,在繁殖期前,其能量平衡策略为能量摄入最优化策略,尽可能多的时间分配在采食上;雄性蒙原羚繁殖期及繁殖期后其能量平衡策略转变为能量支出优化策略,尽可能少的支出能量,尽可能多的时间分配在卧息上。     

Energy intake, energy expenditure, and reproductive costs of female wild golden lion tamarins (Leontopithecus rosalia)

Callitrichid females are often described as energetically constrained. We examined the energy budgets of 10 female wild golden lion tamarins (GLTs, Leontopithecus rosalia) in an effort to understand how energy intake and expenditure might influence physical condition and therefore reproductive performance. We used focal animal sampling to record behavioral data and conducted energy analyses of foods consumed by GLTs to estimate intake and expenditure. We used two-tailed Wilcoxon signed-rank tests to compare intake in the reproductive vs. nonreproductive period and expenditure in the reproductive vs. nonreproductive period. Energy intake decreased during the reproductive period compared to the nonreproductive period. While total expenditure did not vary significantly across the two periods, females spent more time and therefore expended significantly more energy engaged in energetically inexpensive behaviors (i.e., sleeping or being stationary) during the reproductive period compared to the nonreproductive period. We suggest that reproductive female GLTs may adopt a reproductive strategy that includes high intake prior to pregnancy and lactation, and energy conservation during pregnancy and lactation.     

Oocyte growth and follicular hierarchy may be locally controlled by an inhibin-like protein in the lizard Podarcis sicula.

The lizard Podarcis shows an ovarian annual cycle with three to four ovulatory waves between April and July (reproductive period). In August to September, a refractory stage occurs, followed by a nonreproductive period (October to March), during which the oocytes undergo slow growth and prepare themselves for vitellogenesis and ovulation. In the reproductive period, only a certain number of oocytes start growing, giving rise to a follicular hierarchy, which is controlled by still unknown mechanisms. In the present paper, immunoreactive inhibin was detected in previtellogenetic follicles of the reproductive period, and in particular, in the pyriform cells of the follicular epithelium. As the follicle grew and the pyriform cells disappeared, immunostaining shifted to the oocyte cytoplasm. The smaller follicles did not show any immunoreactivity. In the nonreproductive period, no follicles were labeled. We conclude that in the reproductive period, inhibin characterizes the follicles destined to ovulation and might be one of the main factors controlling follicular hierarchy.     

Caste ratios affect the reproductive output of social trematode colonies

Intraspecific phenotypic diversification in social organisms often leads to formation of physical castes which are morphologically specialized for particular tasks within the colony. The optimal caste allocation theory argues that specialized morphological castes are efficient at specific tasks, and hence different caste ratios should affect the ergonomic efficiency, hence reproductive output of the colony. However, the reproductive output of different caste ratios has been documented in few species of insects with equivocal support for the theory. This study investigated whether the ratios of nonreproductive and reproductive morphs affect the reproductive output of a recently discovered social trematode, Philophthalmus sp., in which the nonreproductive members are hypothesized to be defensive specialists. A census of natural infections and a manipulative in vitro experiment demonstrated a positive association between the reproductive output of trematode colonies and the ratio of nonreproductive to reproductive morphs in the presence of an intra‐host trematode competitor, Maritrema novaezealandensis. On the contrary, without the competitor, reproductive output was negatively associated with the proportion of nonreproductive castes in colonies. Our findings demonstrate for the first time a clear fitness benefit associated with the nonreproductive castes in the presence of a competitor while illustrating the cost of maintaining such morphs in noncompetitive situations. Although the proximate mechanisms controlling caste ratio remain unclear in this trematode system, this study supports the prediction that the fitness of colonies is influenced by the composition of specialized functional morphs in social organisms, suggesting a potential for adaptive shifts of caste ratios over evolutionary time.     

Reproductive status effects of pair-housed male pigs on natural,agonistic and sexual behaviours

Boar rearing, which avoids pain and suffering caused by surgical castration, provides better performance, a greater deposition of muscle tissue and leaner carcasses and thus has beneficial effects on both animal welfare and the product. Some countries that do not slaughter boars must consider their boar taint and aggressive and sexual behaviours. Considering that pigs are housed in large groups, which may complicate the formation of social hierarchies and increase fighting and mounting behaviours, some studies have conducted research with reduced numbers of pigs per pen, but these behaviours continued to be observed. However, a study of the reproductive status of pair-housed male pigs has yet to be reported. The aim of this study was to determine whether the reproductive status of uncastrated, immunocastrated and surgically castrated pair-housed male pigs alters their natural, agonistic and sexual behaviours. A total of 48 male pigs from Agroceres PIC™ genetics were assigned to three groups: surgically castrated (barrows), immunocastrated and uncastrated (boars). Natural, aggressive and sexual behaviours of the pigs were assessed by direct observations during four periods of 12 h each (six, five and three weeks before slaughter and the slaughter week). The pigs were housed in pairs from the growing phase until slaughter. Animal behaviour was observed from the finishing phase to slaughter. Carcass lesions were assessed according to five different classes (one: no injury; two to five: severely injured). Overall, boars spent more time lying and less time eating and drinking than barrows. In total of all the periods (48 h), boars expressed more aggressive and sexual behaviours than barrows, whereas immunocastrated pigs displayed similar behaviours to boars, before and after the second vaccine dose. No differences in carcass lesions between treatments and no prevalence of carcasses with severe injuries were observed. In conclusion, the reproductive status of pair-housed male pigs did not change the natural behaviour of boars, immunocastrated pigs or barrows. The agonistic and sexual behaviours of boars and barrows remained unchanged. When housing pigs in pairs, immunocastrated pigs presented similar agonistic and sexual behaviours to boars before and after the second immunocastration vaccine dose. The use of pair-housed uncastrated male pigs has generated welfare benefits for these animals, as the number of carcasses with injuries did not differ from barrows and immunocastrated pigs.     

Genome-wide analysis of alternative reproductive phenotypes in honeybee workers

A defining feature of social insects is the reproductive division of labour, in which workers usually forego all reproduction to help their mother queen to reproduce. However, little is known about the molecular basis of this spectacular form of altruism. Here, we compared gene expression patterns between nonreproductive, altruistic workers and reproductive, non-altruistic workers in queenless honeybee colonies using a whole-genome microarray analysis. Our results demonstrate massive differences in gene expression patterns between these two sets of workers, with a total of 1292 genes being differentially expressed. In nonreproductive workers, genes associated with energy metabolism and respiration, flight and foraging behaviour, detection of visible light, flight and heart muscle contraction and synaptic transmission were overexpressed relative to reproductive workers. This implies they probably had a higher whole-body energy metabolism and activity rate and were most likely actively foraging, whereas same-aged reproductive workers were not. This pattern is predicted from evolutionary theory, given that reproductive workers should be less willing to compromise their reproductive futures by carrying out high-risk tasks such as foraging or other energetically expensive tasks. By contrast, reproductive workers mainly overexpressed oogenesis-related genes compared to nonreproductive ones. With respect to key switches for ovary activation, several genes involved in steroid biosynthesis were upregulated in reproductive workers, as well as genes known to respond to queen and brood pheromones, genes involved in TOR and insulin signalling pathways and genes located within quantitative trait loci associated with reproductive capacity in honeybees. Overall, our results provide unique insight into the molecular mechanisms underlying alternative reproductive phenotypes in honeybee workers.     

Endocrine Correlates of Reproductive Status in Breeding and Nonbreeding Wild Female Moustached Tamarins

In callitrichid primates, reproduction is usually restricted to a single female per group. Reproductive rate is high and the occurrence of a postpartum estrus can lead to simultaneous lactation and pregnancy. In contrast, nonreproductive females often show ovarian inactivity. However, most studies on callitrichid reproductive physiology have been conducted in captivity, where conditions differ considerably from those in the wild, so that reproductive conditions may be strongly modified. Using fecal estrogen and progestogen measurements to monitor female reproductive status in 2 groups of wild moustached tamarins (Saguinus mystax), we examined 1) whether reproductive females in free-ranging groups also show postpartum estrus and 2) whether nonreproductive females demonstrate signs of ovarian activity. In both reproductive females, clear changes in the excretion pattern of progestogen and estrogen metabolites over time in combination with information on parturition dates allowed us to differentiate between pregnancy, a period of postpartum ovarian inactivity lasting for 54 and 64–82 days, and a period of ovarian activity before conception. Nonreproductive females demonstrated temporal fluctuations in hormone concentrations and absolute hormone levels that were similar to ones in the breeding females during the phase of ovarian activity. The results suggest that, in contrast to most captive female tamarins, reproductive females in wild groups of moustached tamarins do not have a postpartum estrus and that nonreproductive females show ovarian activity despite the presence of a breeding female. We therefore conclude that findings from captivity should be only carefully compared to the situation in the wild.     

Castration does not decrease nonreproductive aggression in yearling male European starlings (Sturnus vulgaris)

In the nonbreeding season, some bird species express high levels of aggression despite basal plasma testosterone (T) concentrations. Consequently, nonreproductive aggression is believed to be independent of plasma T. In the present study, we investigated the effect of castration on nonreproductive aggressive behavior in yearling male European starlings (Sturnus vulgaris). We paired castrated (Cx) with control (C) males in dyadic trials during three test periods (December, January-February, and March-April), and by using an infrared camera, we defined which male was the most aggressive one when both males were competing over access to a nest box to roost in. During each of the three periods, Cx males behaved more aggressively than C males but differences between groups did not reach significance. When analyzing the results of the three periods together, Cx males were found to be significantly more aggressive than C males. Likewise, when considering only the second and third period (when plasma T levels of C males were significantly higher than those of Cx males) the same result was obtained. Furthermore, in the third period, aggression tended to be lower than in the first and second period, although T concentrations of C males were highest in this period. Our data thus clearly show that nonreproductive aggression in yearling male starlings is independent of gonadal sex steroids and suggest it even increases by castration.     

Morphological convergence during pregnancy among predator and nonpredator populations of the livebearing fish Brachyrhaphis rhabdophora (Teleostei: Poeciliidae)

Predation can drive morphological divergence in prey populations, although examples of divergent selection are typically limited to nonreproductive individuals. In livebearing females, shape often changes drastically during pregnancy, reducing speed and mobility and enhancing susceptibility to predation. In the present study, we document morphological divergence among populations of nonreproductive female livebearing fish (Brachyrhaphis rhabdophora) in predator and nonpredator environments. We then test the hypothesis that shape differences among nonreproductive females are maintained among reproductive females between predator and nonpredator environments. Nonreproductive females in predator environments had larger caudal regions and more fusiform bodies than females in nonpredator environments; traits that are associated with burst speed in fish. Shape differences were maintained in reproductive females, although the magnitude of this difference declined relative to nonreproductive females, suggesting morphological convergence during pregnancy. Phenotypic change vector analysis revealed that females in predator environments became more similar to females in nonpredator environments in the transition from nonreproductive to reproductive. Furthermore, the level of reproductive allocation affected shape similarly between predator environments. These results suggest a life‐history constraint on morphology, in which predator‐driven morphological divergence among nonreproductive B. rhabdophora is not maintained at the same level during pregnancy. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 386–392.     

Bioenergetics of reproduction and pup development in a subterranean rodent (Ctenomys talarum)

The objective of this study was to evaluate the maternal costs of reproduction and pup development in the subterranean rodent Ctenomys talarum (Thomas 1898). Statistical differences were detected in whole-animal metabolic rates between nonreproductive and pregnant or lactating females. Whole-animal metabolic rates during pregnancy and lactation were 128% and 151% of the resting metabolic rate (RMR) observed in nonreproductive females. The total additional energy cost of reproduction (above the nonreproductive level) was similar for both the gestation and lactation periods. Mass-specific RMR revealed an upregulation of cell or tissue metabolism during lactation but not during gestation. The mass-specific metabolic rate of pups was 237% of the adults' metabolic rates. No differences were observed in body temperature among nonreproductive, pregnant, or lactating females. No differences were detected in body mass at birth among pups from litters with different numbers of nestlings. Pups increased their body temperature, reaching adult temperature at 30 d of age, when they were near weaning. Milk constituted the exclusive food for pups until they started eating solid food at 10 d old. Suckling time decreased with age of pups, and at the same time, mother chases directed toward their pups increased. These reproductive characteristics may contribute to successful existence in a subterranean habitat.