中华山蝠繁殖生态的研究

借助了Mini-2型超声波接收器,采用标志重捕法,结合录音、录像、拍照等方法,对四川师范学院校舍的中华山蝠繁殖生态进行了研究。结果表明：中华山蝠集群繁殖,产仔育幼期雌蝠与雄蝠分离,形成母子群,4月中下旬开始受乳孕,5月下旬到6月下旬产仔多是一胎两仔,极个别一胎一仔。初生仔性比为1.1:1(♀/♂）,幼蝠不选择母体,母蝠则只哺育自己的幼仔,幼蝠5周龄后开始飞翔,独立生活前辈的成活率约为72.20%,3个半月性成熟。当年仔参与交配,幼仔独立生活后,逐渐与母蝠分离,9月中旬到10月上旬交配,交配后绝大部分迁移。     

毛腿鼠耳蝠、亚洲长翼蝠和栗鼠耳蝠斑驳白化现象

斑驳白化是一种先天性颜色失调表型,在翼手目中较为罕见。2016年5月至8月期间,分别在3个省份共发现3种存在斑驳白化现象蝙蝠。在河南省内乡县七里坪乡北湾村,发现1只怀孕雌性斑驳白化毛腿鼠耳蝠(Myotis fimbriatus),斑驳区域包括背部左侧区域及腹部左侧边缘一带。在陕西省柞水县下梁镇,发现1只怀孕雌性斑驳白化亚洲长翼蝠(Miniopterus fuliginosus),斑驳部位包括背部下端、腹部底端股骨边缘、左右股骨、尾骨及小部分尾膜区域。在云南省晋宁县双河乡法古甸村,发现2只斑驳白化雄性栗鼠耳蝠(Myotis badius),斑驳区域分别为背部左下侧和背颈部一侧,区域面积较小。其中,毛腿鼠耳蝠和栗鼠耳蝠的斑驳白化现象为国内首次报道。此外,通过测量蝙蝠体重、前臂长等体型参数,并与同种正常个体进行比较,发现斑驳白化亚洲长翼蝠体重偏大,1只斑驳白化栗鼠耳蝠前臂长偏大,其余斑驳白化蝙蝠体型数据均在正常范围内,表明斑驳白化现象对蝙蝠的正常生存与繁殖未造成严重影响。这为将来斑驳白化蝙蝠的生理生态研究提供科学依据。     

基于核基因RAG1部分序列探讨菊头蝠科和蹄蝠科的系统发育关系

应用核基因重组激活基因1(Recombination activating gene,RAG1)部分序列对贵州9种菊头蝠和5种蹄蝠的系统发育关系进行了研究,运用贝叶斯法(Bayesian inference,BI)、最大似然法(Maximum likelihood,ML)和邻接法(Neighbor-joining,NJ)构建了系统进化树。研究结果表明:1.菊头蝠科和蹄蝠科形成两个平行的分支,支持它们是两个平行科的结论。2.马铁菊头蝠是菊头蝠科中第一个独立出来的亚分支,与其余8种菊头蝠的亲缘关系最远;Rhinolophus sp.与大菊头蝠聚合为一支,推测Rhinolophus sp.可能是大菊头蝠,或者是大菊头蝠的近缘种,它们是继马铁菊头蝠之后分离出来的第二亚分支;中华菊头蝠、栗黄菊头蝠、中菊头蝠聚合为第三亚分支,贵州菊头蝠、大耳菊头蝠、菲菊头蝠聚合为第四亚分支,此两分支形成姊妹群。3.在蹄蝠科的亚分支中,三叶蹄蝠、小蹄蝠、普氏蹄蝠依次分离出来,最后分出的是大蹄蝠和中蹄蝠。     

基于核基因RAG2部分序列探索菊头蝠总科、蝙蝠科和鞘尾蝠科物种的系统发育关系

采用PCR技术获得了翼手目(菊头蝠总科、蝙蝠科以及鞘尾蝠科)16种19个个体的核基因重组激活基因2(Recombination activating gene,RAG2)部分序列,长度为730～760 bp.结合从Genbank中提取的翼手目3科14个体的RAG2序列,通过构建贝叶斯(Bayesian inference,BI)和最大似然树对翼手目种属间的系统进化关系进行研究.研究表明:在菊头蝠总科中,菊头蝠科和蹄蝠科是两个独立的科,且在蹄蝠科中,大蹄蝠、中蹄蝠、普氏蹄蝠3种之间的亲缘关系非常近;蝙蝠科中的南蝠属与棕蝠属是姊妹群;长翼蝠亚科应提升为长翼蝠科.此外,鞘尾蝠科与犬吻蝠科形成姊妹群关系.     

安徽的蹄蝠和鼠耳蝠

蹄蝠(Hipposideros)已知有47种(Honacki1982),主要分布于非洲、南亚、澳洲北部等热带及亚热带地区。非洲的H.commersoni是小蝙蝠亚目中最大的种类(重180克、前臂长达110毫米)。马来半岛和新加坡的H.ridleyi,1978年被IUCN列为濒危蝠种。我国有4种蹄蝠,安徽省已知两种,多见于沿江及皖南地区。一、大蹄蝠H.armiger swinhoei Peters(5月,泾县、东至)9♂♂,10♀♀。常数十或数百只群居。同栖者有普氏蹄蝠、中菊头蝠、皮氏菊头蝠、鲁氏菊头蝠、中华鼠耳蝠、毛腿鼠耳蝠、绒鼠耳蝠和折翼蝠等。雄蝠阴茎长约10毫米,冬季睾丸约7×4-8×5毫米。5月…     

海南和广西中蹄蝠形态及Cyt b 基因序列的比较

中蹄蝠亚种的划分、分布及有效性尚不清楚,国内学者的观点不一致。为了探讨中国不同地区中蹄蝠的形态差异和亚种分化,运用软件SPSS 13. 0 对广西和海南中蹄蝠的17 项外部形态和25 项头骨指标进行主成分分析和判别分析,并用Mega 5 软件比较了它们的线粒体Cyt b 基因序列的差异,结果表明广西和海南的中蹄蝠在外形及头骨形态上均有明显差异,两地中蹄蝠外形6 项指标、头骨10 项指标有明显差异的个体数超过75% ,两地样本的Cyt b 基因序列分歧度为3. 7% - 4.4%,外形、头骨及Cyt b 基因序列的差异均已达到亚种分类水平,海南和广西的中蹄蝠应为不同的亚种。     

普氏蹄蝠栖息地选择的研究

为了解普氏蹄蝠(Hipposideros pratti)栖息地的特征、微环境条件及影响该物种栖息地选择的因素,2016年6月至2019年9月,在我国中、南部的10个省或直辖市,对83个洞穴进行测量,记录洞穴微环境,评估洞穴内普氏蹄蝠的受干扰程度,对普氏蹄蝠生态习性进行初步观察.运用独立样本t检验和卡方检验评估普氏蹄蝠的...     

广东7 种蝙蝠的核型研究

对采集于广东的4 科7 种蝙蝠进行了核型分析,它们的核型分别是:犬蝠(Cynopterus sphinx)2n =34,FN= 58;印度假吸血蝠(Megaderma lyra)2n = 54,FN = 104;大耳双色蹄蝠(Hipposideros pomona)2n = 32,FN =60;中蹄蝠(H. larvatus)2n = 32,FN = 60;大卫鼠耳蝠(Myotis davidii)2n = 46,FN = 52;大黄蝠(Scotophilus heathi)2n = 36,FN = 54;南长翼蝠(Miniopterus australis)2n =46,FN = 50。其中大耳双色蹄蝠和大卫鼠耳蝠的核型为首次报道,犬蝠、印度假吸血蝠、中蹄蝠、大黄蝠和南长翼蝠的核型为中国第一次报道。     

澳门翼手类物种多样性调查

2009 ～2012 年,对澳门翼手目(蝙蝠)物种多样性进行了调查。结果共捕捉到10 个物种,属5 科8 属,其中包括澳门原来记载的2 个物种,即蹄蝠科的大蹄蝠(Hipposideros armiger)和蝙蝠科的东亚伏翼(Pipistrellus abramus);本研究新增加8 个物种,即狐蝠科的犬蝠(Cynopterus sphinx) 和棕果蝠(Rousettus leschenaulti),鞘尾蝠科的黑髯墓蝠(Taphozous melanopogon),菊头蝠科的菲菊头蝠(Rhinolophus pusillus),以及蝙蝠科的大足鼠耳蝠(Myotis ricketti)、普通伏翼(P. pipistrellus)、普通长翼蝠(Miniopterus schreibersi) 和南长翼蝠(M. pusillus)。另外,通过野外录音和分析,并与已发表物种声音特征比较核对,发现菊头蝠科和蹄蝠科各一种,前者可能是泰国菊头蝠(R. siamensis)或者中菊头蝠(R. affinis),后者可能是果树蹄蝠(H. pomona) 或者三叶蹄蝠(Aselliscus stoliczkanus)。本文对已捕捉10 种蝙蝠的分布、形态特征和回声定位叫声特征进行报道,同时对其种群数量和保护现状进行了讨论。保护蝙蝠栖息生境(洞穴、古老建筑和蒲葵树等) 对保护澳门蝙蝠物种多样性至关重要。     

贵州省果树蹄蝠的分类记述

2008年10月在贵州省荔波县进行翼手目动物多样性调查中,于该县永康乡采集到2号蹄蝠标本,经与国内外记载过的蹄蝠科bicolor族群的标本进行比较,这2号标本的体型较小,前臂长分别为44.26mm、42.48mm,耳大而圆,耳长22.02mm、22.58mm;鼻叶简单,前鼻叶外侧没有小附叶,中鼻叶不发达;后鼻叶稍宽于前鼻叶和中鼻叶,被3纵隔分为4个部分,P2弱小,但未消失,位于齿列线外侧,这些特征与中国和泰国记载的果树蹄蝠Hipposideros pomona一致。另对贵州早期文献中记载的双色蹄蝠H.bicolor标本进行了查阅,认为其应归为果树蹄蝠。     

Influence of colony size on pup fitness and survival in South American sea lions

Increased terrestrial pup mortality in small colonies due to harassment by subadult males has been proposed as a mechanism to explain the stagnation of South American sea lion populations after sealing ended. To test this hypothesis, pup survival rate was assessed in five northern Patagonia colonies with different sizes. Female diet quality as well as pup growth rate and immune status from the largest and smallest of these colonies were also assessed. Results indicated that the pup survival rate increased with colony size and pup‐to‐subadult male ratio. Furthermore, pups grew faster in the smallest colony, although female diet composition and pup immune status did not differ between the two colonies. Inverse relationship between pup growth rate and survival rate indicated that mortality was independent of food supply. In absence of terrestrial predators, infanticide by subadult males is the only mortality source other than starvation and illness and the relationship between pup survival rate and pup‐to‐subadult male ratio approached a type II functional response curve. Thus, infanticide stands as the most likely reason for the observed positive relationship between colony size and pup survival rate, supporting the hypothesis that post‐sealing population stasis was caused by inverse density dependence.     

Parthenogenesis in a whitetip reef shark Triaenodon obesus involves a reduction in ploidy

Genetic analysis of a female whitetip reef shark Triaenodon obesus and her stillborn pup, assumed to be of parthenogenetic origin, revealed that the pup was homozygous at all 24 nuclear‐encoded microsatellites assayed, consistent with the idea that diploidy in the pup had been restored via terminal fusion. Flow cytometric analysis, however, indicated that the genome size of the pup was no more than half that of the mother, and microscopy revealed that nuclear volume was c. 1·73 times larger in the mother than in the pup. Together these data suggest that the pup was genetically haploid, developing directly from an unfertilized egg; as far as is known, this is the first observation of a spontaneously produced haploid vertebrate.     

Pup mortality in southern elephant seals at Marion Island

Pre- and early post-weaning pup mortality of southern elephant seals (Mirounga leonina) at Marion Island from 1990 through 1999 ranged from 1.6% to 7.3% and averaged 3.8%. Mortality of pups after weaning before their first trip to sea accounted for only 12% of the total mortality. We found no relationship between population size and percentage pup mortality, indicating that pup survival is independent of seal density, at least at the densities of breeding seals that prevailed. Indeed, pup mortality was greatest in the smallest harems, apparently owing to a greater number of younger, less experienced mothers. Small harems were generally also found on less suitable beaches than larger harems and this could have contributed to pup injury as a cause of pup mortality on these beaches. Mother-pup separation and injury caused by beachmasters is likely to be responsible for pup mortality in the larger harems. The low rates of pup mortality observed in this study obviate it being a major population regulating agent at Marion Island.     

Offspring food allocation by parents and helpers in a cooperative mammal

In cooperatively breeding species, helpers and parents commonlyface two decisions when they find a food item: first, whetherto feed the item to a young group member or to eat it themselves;and second, which offspring to feed. Little is known aboutthe factors that influence these decisions in cooperative mammals,though optimal foraging theory provides a basis for a rangeof predictions. In this article we describe pup feeding behaviorby helpers and parents in a cooperative mongoose, the meerkat(Suricata suricatta). When meerkat pups begin accompanyingthe group, they beg food from older group members, who digup dispersed prey items. As predicted, the probability of aprey item being fed to a pup shows a positive relationship with prey size and a negative relationship with pup distance.Meerkats apparently follow a "feed the nearest pup rule" andare more likely to feed the nearest pup if it is hungry. Hungrierpups beg more and follow older group members more closely.Across all age categories, females feed pups more frequentlythan males, both in terms of the relative frequency of feeds,and the proportion of prey biomass found by each individualthat is fed to pups. Females also feed female pups significantlymore than male pups, while males feed pups of both sexes equally.These sex biases in feeding contributions may result from femalegroup members benefiting more than males from higher pup survival,and in particular higher female pup survival, because femalesare the philopatric sex.     

Inter-sexual differences in Antarctic fur seal pup growth rates: evidence of environmental regulation?

We investigated the variation of Antarctic fur seal (Arctocephalus gazella) pup growth rates in response to sex, breeding season and duration of both maternal foraging trip and attendance bouts. Data were collected during five consecutive rearing seasons at Cape Shirreff, the most important breeding colony in the South Shetland Islands, Antarctica. Our results showed significant interannual and sexual variations in pup growth rates. Male pups grew significantly faster than female pups during 2000, 2001, 2002 and 2004 seasons, whilst during 2003 no difference was found. The interannual variation in pup growth rates was correlated with the interannual fluctuation in maternal foraging trip and attendance bouts. There was a significant effect of pup sex and maternal foraging trip duration on pup growth rates, which varied between years having foraging trip duration a major effect during 2003, when females spent more time at sea and interestingly on that year there were no sexual differences in pup growth rates. The effect of attendance bout on pup growth rates was not significant. Diet analysis showed that Antarctic krill (Euphausia superba) was the most frequent prey item during the study period. Analysis of krill size distribution showed a significant difference in krill length, during 2003, when A. gazella preyed upon the smallest sizes of krill. In this study, sex was the most important factor on pup growth rates, but when prey availability seemed more limited, there are longer foraging trips and shorter attendance bouts the sex factor became less significant.     

No infanticide in the hystricognath rodent, Octodon degus: does ecology play a role?

The behavior of male and female Octodon degus (Hystricognathi; Octodontidae) was studied in captivity to examine the occurrence of non-parental infanticide, which involves the killing of immature infants by adult conspecifics other than the genetic parents. Sexually inexperienced male and female, and lactating female degus were tested for their behavior toward genetically unrelated, and socially unfamiliar, degu pups in a neutral arena. No male or female degu showed any sign of aggression toward the pups. Lactating females tended to exhibit the shortest latency to first behavioral interaction with the pup and the highest rate of social interactions with the pup, and they spent a relatively high proportion of their time in proximity with the pup. In contrast, males tended to show the longest latency to first pup contact and a reduced rate of interactions with the pup, and they spent a relatively small fraction of their time with the pup. The behavior of non-breeding females seemed intermediate between that of males and lactating females. Given that social and ecological conditions posed to promote non-parental infanticide in other rodents seemed not particularly different from what is known of degu biology, ecology, and social behavior, lack of degu infanticide may reflect phylogenetic inertia instead of an absence of conditions favoring infanticide. Received: 8 January 2000 / Received in revised form: 16 June 2000 / Accepted: 20 June 2000     

Lactating Females Do Not Discriminate Between Their Own Young and Unrelated Pups in the Communally Breeding Rodent, Octodon degus

Females in numerous rodent species engage in communal nesting and breeding, in which they share one or more nests to rear their young. A potential cost of communal nesting and breeding is that mothers divert resources to unrelated offspring. One way mothers could avoid this cost is to recognize and favour their own young over unrelated offspring when allocating maternal effort. We assessed whether female degus (Octodon degus), a communally nesting and breeding caviomorph rodent, discriminate between their own and unrelated offspring during lactation. Female degus previously have been shown to distinguish between their own and unrelated pups when exposed to odours from both. We measured pup discrimination based on differences in the retrieval behaviour of females that were in early or intermediate lactation directed towards their own and unrelated offspring; offspring presented were of similar or different age. Before any event of pup retrieval, lactating females spent similar amounts of time and interacted to a similar extent with their own and unrelated pups. During pup retrieval, all lactating females transported both pups to the nest. Neither relatedness to pups, nor pup‐age differences, influenced the order in which pups were retrieved to the nest. Dams waited similar amounts of time before retrieving the first pup when the first transported young was their own or unrelated. Likewise, females waited similar amounts of time before retrieving the second pup when the pup transported first was their own or unrelated. The time between first and second pup transport events was longer when dams were in early when compared with intermediate lactation, but only when pups were of similar age. All experimental subjects nursed unrelated pups after they were retrieved. Collectively, our results do not support the hypothesis that communally breeding female degus use their recognition ability to discriminate against unrelated offspring in favour of their own young.     

Offspring kidnapping with subsequent shared nursing in Antarctic fur seals

Non-offspring maternal care should be common in phocids, but their occurrence would be uncommon among otariids due to the high costs of raising offspring, particularly lactation, and an efficient recognition system that allow for accurate recognition during the frequent mother–pup re-associations. However, non-offspring maternal care has been documented in some otariid species. While the phenomenon in general is not novel among the colonially breeding seals, the exclusive care to a single pup by two lactating females for an extended time is a behavior scarcely documented in natural population. In an extension of this allonursing care, we document the first case of the kidnapping of a pup with subsequent shared nursing in Antarctic fur seal including data on the effect of this interaction on the pup’s growth. While all other lactating females nursed exclusively their own pups, the shared nursing was advantageous for the pup because he grew noticeably larger (in weight and axillary girth) than other of his cohort, particularly after 50 days. This advantage would have been influenced by the asynchrony of the foraging cycle of the biological and foster mother, which resulted in a higher attendance on shore than any other male pups. Although several explanations have been hypothesized for allolactation in mammals, our observations suggest a misguided parental care, associated with recognition errors by the foster mother whose pup was stillborn.     

Male germ line stem cells have an altered potential to proliferate and differentiate during postnatal development in mice

Spermatogonial stem cells (SSCs) continuously support spermatogenesis after puberty. However, accumulating evidence suggests that SSCs differ functionally during postnatal development. For example, mutant mice exist in which SSCs support spermatogenesis in the first wave after birth but cease to do so thereafter, resulting in infertility in adults. Studies using a retroviral vector have shown that the vector transduces pup SSCs more efficiently than adult SSCs, which suggests that pup SSCs divide more frequently. Thus, it is hypothesized that the SSCs in pup and adult testes have different characteristics. As an approach to testing this hypothesis in the present study, we investigated the proliferation kinetics of pup SSCs (6-9 days old) and their self-renewal/differentiation patterns for the first 2 mo after transplantation, and compared them to those of adult SSCs. Using serial transplantation, we found that the number of pup SSCs declined over the first week after transplantation. Thereafter, it increased ~4-fold by 1 mo and ~9-fold by 2 mo after transplantation, which indicates that pup SSCs continuously proliferate from 1 wk to 2 mo after transplantation. Compared to the proliferation of SSCs derived from adult intact testes, that of pup SSCs was lower at 1 mo but similar at 2 mo, indicating the delayed proliferation of pup SSCs. However, the pup SSCs regenerated spermatogenic colonies at 1 mo that were similar in length to those of SSCs from adult intact testes. Therefore, these results suggest that some functional differences exist in SSCs during postnatal development, and that these differences may affect the abilities of SSCs to self-renew and differentiate.