圈养小熊猫繁殖行为变化及繁殖行为对策

In order to investigate the change of reproductive behaviors and understand reproductive strategies of both male and female red pandas, one-year behavioral observation was conducted through the focal sampling method in the Chengdu Research Base of Giant Panda Breeding from December 1999 to November 2000. Our results indicated that reproductive behaviors showed significant differences between the estrous and non-estrous seasons. Frequencies of the rubbing anogenital, sniffing and licking marking were much higher in estrus than in non-estrus. Bleating only appeared in the estrus and can be regarded as an estrous indicator.The result also demonstrated that both male and females applied different reproductive behavioral strategies. Frequencies of activity, rubbing anogenital, licking and sniffing marking, and bleat were much higher in the male than in the female. However, those of resting and investigating were much lower in the male than in the female. This indicated that the male was more active than the female during the estrus and might imply that the male acts mainly as an estrous message sender, and the female as a message receiver in the estrous season.     

Predating strategy of rodents on acorns of Quercusaliena var. acuteserrata under different predating risks and fate of acorns

The effects of rodents on forest regeneration have been highlighted in many ecological studies. In 2002 and 2003, the acorns of Quercus aliena var. acuteserrata were subjected to 12 different treatments. The daily dynamics and the amount of acorns that were finally left intact, predated in situ, or removed off were examined and documented. The ratios of acorns that were infested by bugs before and after predation by rodents were carefully documented. It was found that: (1) the ratios of acorns infested by bugs before and after predation by rodents showed significant difference (P > 0.05), suggesting that rodents would not prey on acorns during the predating process if acorns had been already infested by bugs. (2) When compared with the controls, the fate of acorns could be roughly classified into four types: acorns that were simply buried or placed on black paper showed no significant differences with the controls in their response to rodents, suggesting that rodents have no sensitivity to the little change of odor resulting from burying and may be more adapted to black background. Acorns attached with strings, dyed with black ink, cut into halves, or placed on white/green/red paper were predated in situ with much lower predation rates and lasted the same duration. Compared with the controls, the acorns were removed away by rodents with the same first day rate and the removal lasted longer. The final removal rate of the acorns by rodents was increased, whereas that of predation in situ was decreased, and none were left in the spot. This may suggest that rodents in this case increased their predation risk expectation and adopted a strategy of “less predation proportion in situ”. Acorns that were burnt were not predated in situ as well as removed in the first day, but the rates were raised to the maximum in the forth and fifth day and then declined to zero. Consequently, the final ratios of predation in situ and removal considerably decreased with many acorns, nearly 50%, being left intact. It can be hypothesized that the rodents responded to the change in odor of acorns by using the strategies of “less predation proportion in situ” and “less predating activities”, thereby resulting in larger number of acorns remained intact. Acorns that were enwrapped were barely predated in situ, removed in the first day with a normal predation rate, which declined to nearly zero in the second day and then increased till it declined again from the fourth day to the final day. The final rate of predation in situ was lower than 5% without acorns remained intact, and the rate of removal of acorns showed a considerable relative increase. This suggests that when there was a change in both odor and status of acorns, rodents also adopted the “spying” and “less predation proportion in situ” strategy, Because the predation risk is critical, the sense of sight would play an important role in rodent's living. (3) Definite amounts of acorns were predated in situ, discarded, removed away, predated ex situ, lost and hoarded separately.     

Predating strategy of rodents on acorns of Quercusaliena var. acuteserrata under different predating risks and fate of acorns

The effects of rodents on forest regeneration have been highlighted in many ecological studies. In 2002 and 2003, the acorns of Quercus aliena var. acuteserrata were subjected to 12 different treatments. The daily dynamics and the amount of acorns that were finally left intact, predated in situ, or removed off were examined and documented. The ratios of acorns that were infested by bugs before and after predation by rodents were carefully documented. It was found that: (1) the ratios of acorns infested by bugs before and after predation by rodents showed significant difference (P > 0.05), suggesting that rodents would not prey on acorns during the predating process if acorns had been already infested by bugs. (2) When compared with the controls, the fate of acorns could be roughly classified into four types: acorns that were simply buried or placed on black paper showed no significant differences with the controls in their response to rodents, suggesting that rodents have no sensitivity to the little change of odor resulting from burying and may be more adapted to black background. Acorns attached with strings, dyed with black ink, cut into halves, or placed on white/green/red paper were predated in situ with much lower predation rates and lasted the same duration. Compared with the controls, the acorns were removed away by rodents with the same first day rate and the removal lasted longer. The final removal rate of the acorns by rodents was increased, whereas that of predation in situ was decreased, and none were left in the spot. This may suggest that rodents in this case increased their predation risk expectation and adopted a strategy of “less predation proportion in situ”. Acorns that were burnt were not predated in situ as well as removed in the first day, but the rates were raised to the maximum in the forth and fifth day and then declined to zero. Consequently, the final ratios of predation in situ and removal considerably decreased with many acorns, nearly 50%, being left intact. It can be hypothesized that the rodents responded to the change in odor of acorns by using the strategies of “less predation proportion in situ” and “less predating activities”, thereby resulting in larger number of acorns remained intact. Acorns that were enwrapped were barely predated in situ, removed in the first day with a normal predation rate, which declined to nearly zero in the second day and then increased till it declined again from the fourth day to the final day. The final rate of predation in situ was lower than 5% without acorns remained intact, and the rate of removal of acorns showed a considerable relative increase. This suggests that when there was a change in both odor and status of acorns, rodents also adopted the “spying” and “less predation proportion in situ” strategy, Because the predation risk is critical, the sense of sight would play an important role in rodent's living. (3) Definite amounts of acorns were predated in situ, discarded, removed away, predated ex situ, lost and hoarded separately.     

Pedigree investigation of severe hemolytic disease of the newborn caused by rare anti-Jk3

The study was designed to evaluate the molecular and serological features of a newborn with severe hemolytic disease of the newborn (HDN) caused by anti-Jk3, and to further rich our understanding of Kidd subgroup genetics using pedigree analysis which is the first analysis of a Jk null phenotype in China and the first report of severe HDN caused by anti-Jk3. A female baby presented with hyperbilirubinemia (36 μmol/L) on the day of birth. Antibody screening tests using blood samples from the patient and her family indicated that the mother’s plasma contained alloantibodies against high frequency antigens and the results of direct Coombs test were all negative. Kidd phenotypes were Jk(a-b-), Jk(a-b+), and Jk(a-b+) in the mother, father, and baby, respectively. Kidd genotype was determined by PCR amplification of a single nucleotide polymorphism (838) and all family members were Jk(a-b+). Kidd gene exons 4 to 11 were sequenced to identify potential mutations.Sequencing analysis revealed that c.838 G>A and intron c.3 -78 G>A homozygosity occurred in all family members along with homozygosity and heterozygosity for c.IVS5-1G>A in the mother and newborn, respectively. In conclusion, serological and genetic analyses confirmed that the Jk(a-b-) phenotype was caused by homozygous IVS5-1G>A mutation of the Kidd gene. This result is consistent with that of a previous report and presents a useful diagnostic tool to identify HDN caused by anti-Jk3. A further study is required to identify the effect of intron 3 -78 G>A mutation on phenotype.     

Kinetics of thymocyte developmental process in fetal and neonatal mice

Kinetics of thymocyte development in vivo during embryogenesis was pursued. The early development of thymocytes in the fetal and neonatal BALB/c mice was discontinuous, with four waves of cell proliferation occurring at fetal day (Fd) 14 to 17, Fd 18 to day (D) 1 after birth, D 2 to D 5 and D6 thereafter. The first three proliferation waves coincided with the generation of CD4^hiCD8^hi (DP), TCR CD4^hiCD8^-/^loCD8^int/hi(CD4 SP), and TCR CD4^-/^loCD8^int/hi (CD8 SP) thymocytes, respectively. The transition from DN to DP cells was further investigated and it was found out that there were two differential pathways via im-mature single positive (ISP) cells in the BALB/c mice, each functioning at different fetal ages. One is via TCR^-CD4^-CD8^ cells, occurring between Fd 15 and Fd 17 and the other is via TCR^-CD4^ CD86-cells,occurring from Fd 17 until birth. In contrast, the TCR^-CD4^-CD8^ pathway dominated overwhelminglyin the C57BL/6 mice. These findings shed new light on the hypothesis that the differential pathway pref-erence varies with mouse strains. With respect to the shift in the intensity of CD4 and CD8 expression onthymocytes from fetal to adult mice, the TCR CD4^hiCD8^-/^lo, and TCR^ CD4^-/^loCD8^int/hi subsets might be equivalent to the medullary type TCR^ CD4/CD8 SP cells.     

Response of land use/coverage change to hydrological dynamics at watershed scale in the Loess Plateau of China

In this study Qiaozidong and Qiaozixi watersheds in Loess Plateau were selected as the case to investigate the effects of land use/coverage change on hydrological dynamics. The results showed that the runoff coefficient of controlled watershed reduced by about 50%, 85%, 90%, respectively, in wet, normal and dry years in comparison with that of uncontrolled watershed. The average runoff coefficient reduced by 73.6% during the period of 1995–2004 compared with that in the previous period of 1986–1994 for land use in controlled watershed. And the impacts of land use and vegetation changes on runoff were strengthened in response to the increasing rainfall. Additionally, the impacts of land use/coverage change on runoff yield are characterized by seasonal fluctuation. The maximum monthly runoff reduction in the both watersheds occurred in May, which was consistent with the period of the maximum land coverage appeared. Finally, when the rainfall intensity reached a certain threshold, the variance of flood peak in two watersheds reduced, which showed that the effects of forest on flood weakened. The flood peak discharge frequencies indicated that peak discharge would respond to the land use and vegetation change obviously on condition that there were the same frequencies of rainfall intensity in the earlier and later periods.     

Different maternal investment strategies for male and female calves in a polygynous mammal

Mater nal effects occur whe n the phe no type of the mother in flue nces that of the young to the detriment of her survival, growth or fitn ess. The in vestment of the mother can be affected by mater nal body condition and/or experience. Trivers-Willard Hypothesis (TWH) and Local Resource Competition Hypothesis (LRCH) are the main hypotheses used to explain bias in birth sex-ratios in mammals, as well as for sex-biased maternal investment. Both hypotheses suggest that a different amount of investment must be expected according to the sex of the young. However, recent studies suggest that these differences are not in quantity but in the strategies: mechanisms and objectives may differ for each sex. We studied how maternal characteristics (age, body mass, body condition, and domi nance status) influence re leva nt aspects of the birth and early growth of the calf (birth date, birth body mass, body mass at weaning, and body condition at weaning) separately for each sex;and how that investment is mediated by milk production and composition (lactose, fat, and protein). One hundred eighty-eight newborns from 75 captive red deer hinds aged from 2 to 19 years were analyzed. The main differential investment observed was related to birth date: when producing a female, hinds give birth earlier in the season only if they have a good body condition;however, when gestating a male it is the older hinds those which deliver earlier. Subsequently, milk production and composition are correlated with birth body mass in female calves, but to weaning body mass in males. Thus, only hind body mass affects the weaning body mass of female calves, compared with age and hind body mass in males. These results suggest that while TWH fits the maternal investment strategy found for male calves, it is LRCH which correlates with the maternal investment patterns observed for females.     

山西五台山地区褐马鸡的再引入

Brown eared-pheasant Crossoptilon mantchuricum is endemic to China, and mainly occurs in Luliang Mountains of Shanxi, Xiaowntai of Hebei and Huanglong of Shaanxi. Reintroduction of Brown eared pheasant was carried out from April to December in 2000. According to the criterions of release site selection in Guidelines for Reintroductions of IUCN, and habitat selection of Brown eared pheasant, Kuantan forestry in Wutaishan Mountains of Shanxi Province was selected as the release site. Of the 8 released individuals, 5 wild individuals were captured in winter in Luyashan Nature Reserve of Shanxi Province, and 3 were offsprings of captive-reared individuals. Transmitters were attached when the 8 individuals were released. Overall, 6 individuals survived for at least 1 month, and the longest time for survival was 155 days, except that one was confirmed as having been killed by a raptor on the second day and one was lost on the eighth day after release. All moved away from the release site after release and established stable home ranges in different sites after 10 days, respectively. In early May, the individuals again dispersed to establish new home ranges. The wandering distance and days of the captive individuals were longer and the home range size were larger than that of the wild birds,which resulted from the weak adaptability to new habitat for the captive individuals, such as recognizing and fetching food. For wild individuals, the second wandering distance was longer than the first. We believe the difference was related to looking for partners. After wandering, individuals established stable home ranges in different sites [Acta Zoologica Sinica 50 (1): 126-132, 2004].     

笼养红斑羚生态生物学的初步观察

This study presents the results of a demographic analysis of 20 years of birth and death records of red gorals kept at the Shanghai Zoo.The age of the first successful breeding,sex ratio at birth,seasonality of reproduction and mortality rate are presented.The females or males of red goral born in captivity can give their first birth at the age of 2 or 3 separately.The births mainly occurred from May to July and peaked in June.Ratio of females to males at birth was 2.36:1.1 The mortality rate for infants and adults were 23.1% and 11.8%,respectively while there was no sub-adult death recorded during the 20 years period.There was a definite relation between mortality rate and seasons and mainly in July.     

Relationship between leaf photosynthetic function at grain filling stage and yield in super high-yielding hybrid rice (Oryza sativa. L)

The characteristics of dry matter production before and after heading and the relationships between photosynthesis of flag leaves and dry matter accumulation in panicles were investigated on super high-yielding rice cv. Xieyou 9308 (the yield of up to 12 t/ha) with rice cv. Xieyou 63 as a control. The results showed that (i) the capacity of dry matter production before and after heading in Xieyou 9308, i.e. biomass and daily dry matter production, was remarkably higher than that in Xieyou 63, especially after heading; (ii) CO2 assimilation capacity in flag leaves in Xieyou 9308, namely Leaf Source Capacity (LSC), was also significantly higher than that in Xieyou 63, and the supply of photosynthate in leaves and the demand of grain filling were completely synchronous in Xieyou 9308, but photosynthetic function in flag leaves in Xieyou 63 declined sharply 20 days after heading and it was not enough to meet the demand of grain filling. These results confirmed that high efficient photosynthetic function in     

Observation of a birth among wild toque macaques (Macaca sinica)

Most toque macaques give birth to their infants during the night when resting arboreally. Here we report on a birth that occurred in daytime (at 0916 hr) and on the ground. The mother was 7.6 years old; the birth was her second. Prepartum behaviors included lordosis, arching of the back, stretching, squatting, rolling on the ground, and anogenital self-examination. During the birth the female was isolated about 100 m from the rest of her group. The mother stood bipedally during parturition and assisted delivery with her hands. The infant was born within 2 min after first appearing at the vulva. It immediately clung to the mother’s leg and vocalized. The mother licked the infant and oriented it toward her ventrum. She resumed foraging behavior within 20 min after parturition. The infant nursed for the first time 2.25 hr after being born. The mother ate part of the placenta, but the alpha female of the group usurped and also ate a portion of it. Curious group members sniffed and looked at the infant but did not touch it.     

圈养金钱豹产仔及育幼行为初步观察

2005年3月至2006年3月,对成都动物园圈养金钱豹Panthera pardu的自然分娩及1月龄育幼期内的行为采取瞬时取样法进行观察,旨在了解圈养金钱豹的育幼情况.结果 显示:圈养金钱豹母性较强,金钱豹育幼期的主要行为为休息,占所有行为的47.12%～55.8%,其次为观望(18.92%～22.43%)和舔仔(10.1%～13.33%),运动行为较平时减少.在整个育幼期,运动行为呈上升趋势,舔仔行为呈下降趋势.     

Behavioral development of a polar bear cub (Ursus maritimus) in captivity

The difficulty of observing polar bears (Ursus maritimus) in the wild has prohibited the gathering of behavioral data necessary to develop a baseline set of milestones for monitoring cub development. This study describes and quantifies previously undocumented trends in behavior observed in a captive cub–information that will be useful both in future comparative studies and in the implementation of husbandry improvements. Nearly 400 hr of behavioral data were collected, 100 hr of which were video recordings from the maternity den during the first 3 months of life. Den videos were scored to determine activity budgets and levels of maternal contact. For the remainder of the first year, mother and cub were observed in the outdoor enclosure. The onset and relative frequency of 40 discrete cub behaviors were tracked, as were patterns of mother–cub contact, including nursing and weaning. This study revealed that environmental conditions, habitat enrichment, and conditioning procedures influenced the patterns of developmental behavior exhibited by a polar bear cub. Both climatic and developmental factors had significant effects on the time the bears spent swimming. Management practices, such as environmental enrichment, and a conditioning procedure involving separation of mother and cub caused transient changes in several tracked behaviors. As the cub aged, the longest time between consecutive maternal contacts increased. Nursing bouts recorded per hour of observation decreased, and the duration of individual nursing bouts and pre‐nurse begging periods increased. Zoo Biol 22:507–514, 2003. © 2003 Wiley‐Liss, Inc.     

大熊猫超轻初生幼仔的成功哺育

大熊猫初生幼仔体重较轻,仅为正常母体体重的千分之一,平均144.9±40.59 g(张志和和魏辅文,2006).初生体重在70 g以下的幼仔,常被称之为超轻体重幼仔,初生体重超轻、身体瘦弱活动无力,产后无叫声或叫声小是其主要特点.对于体重超轻初生幼仔的育幼,目前有1993年对一例初生体重为61 g的幼仔,在产后两周内采用胃导管喂母初乳、之后采取人工与母兽交替哺育的方法养育存活以及2000年对一只58 g幼仔进行全人工育幼存活7 d的报道(钟顺龙和何光昕,1997,侯蓉等,2000).2006年成都大熊猫繁育研究基地的一只雌性大熊猫产下一对双胞胎,其中一仔初生体重仅51 g,经人工辅助哺育存活,该幼仔是圈养条件下育成的初生体重最轻的大熊猫.现将该例的育幼情况报道于后,以供参考.     

Behavioral development in okapis and giraffes

Observations on the behavioral development of two okapi calves and one giraffe calf were made at Brookfield Zoo. The following behaviors were monitored for 4 to 6 mo after birth; nursing duration and nursing attempts, mother-infant distance, bunting the mother's udder, lying, moving, maternal grooming, mother and infant autogrooming, object licking, tail chewing, and contact by others in the herd. Behaviors in both species showed oscillating patterns with high levels of mother-infant contact behaviors at 3–4 wk, 9–11 wk, and 14–15 wk in okapis. Giraffe infants showed similar oscillations with high periods of contact about 2–5 wk later than those in okapis. Other behaviors oscillated in concert with these, with specific correlations occurring between nursing behaviors and grooming behaviors. A main difference between okapi and giraffe development centered around maternal motivation during the high contact (regressive) periods. In okapis, after 10–12 wk there was a low rate of nursing success, whereas in giraffes the percentage of success in nursing rose with later behavioral oscillations. The regressive periods became conflict periods in okapis, whereas in the giraffe, the mother initiated the periods. This difference was in accordance with the unique strategy of infant rearing in wild giraffes in which there is an extended “hider” period when older calves are left together in shaded areas with an adult sentry. Field studies also indicated probable oscillations of mother-infant contact and a prolonged period of the mother initiating contact with her calf.     

Behavioral budgets of captive sea otter mother–pup pairs during pup development

Instantaneous sampling of eight behavior categories for a captive mother sea otter (Enhydra lutris) and her four pups was conducted continuously during the first three months following each pup's birth. Initially, pup-grooming and rest occupied the largest proportion of the mother's time. Despite a steady decline in the amount of time the mother spent pup-grooming, the mother continued to groom the pup a substantial amount of time three months after the pup's birth. The proportion of time the mother spent resting, self-grooming, or swimming did not change significantly over the study period, suggesting that these behaviors are important to the mother's self-maintenance. The newborn pups' behaviors were initially limited to rest, active, and nursing, with large proportions of time spent resting and nursing. A significant increase in self-grooming occurred regularly by week 2, followed by increases in swimming (week 3), diving (week 6), and feeding (week 7). Three months after birth, the pups' behavior budgets were similar to their mother, with the exception that pups self-groomed substantially less than their mother self-groomed. The lower proportion of pup self-grooming may be due to the continued close proximity to their mother in captivity, which afforded extended association, and allowed the mother to continue to perform this complex behavior for the pup. © 1993 Wiley-Liss, Inc.     

Impaired Maternal Behavior in Usp46 Mutant Mice: A Model for Trans-Generational Transmission of Maternal Care

Usp46 mutant mice (congenic strain on a B6 genetic background; MT mice) have a low weaning rate and display poor maternal behavior compared to C57BL/6J mice (B6 mice). Based on these observations, we examined how maternal behavior is shaped by cross-fostering and in-fostering MT and B6 mice. The experiments consisted of six groups: B6 mice fostered by their biological mother (B6-CO); MT mice fostered by their biological mother (MT-CO); B6 mice fostered by a different B6 mother (B6-IF); MT mice fostered by a different MT mother (MT-IF); B6 mice fostered by an MT mother (B6-CF); and MT mice fostered by a B6 mother (MT-CF). Maternal behavior was assessed using the pup-retrieval test in adult female offspring, and four parameters, time nursing pups in the nest, time sniffing or licking pups, rearing behavior, and latency to retrieve pups, were measured. Cross-fostering significantly reduced time spent nursing and sniffing/licking pup, and increased the number of instances of rearing in the B6-CF group, and improved three parameters of maternal behaviors (nursing, rearing and latency) in the MT-CF group. These results indicate that the level of maternal care is transmitted to their pups and proper maternal behaviors can be shaped if adequate postpartum maternal care is given, even in genetically vulnerable mice. However, the offspring’s genotype may also influence the development of maternal behaviors in adulthood. Thus, MT mice may prove useful as a model for trans-generational transmission of maternal care, and these findings may provide insight into the mechanisms of maltreating behaviors in human child abuse.     

雄性大熊猫对化学信息行为反应的年龄差异

化学通讯对哺乳动物的生存和繁殖起着重要作用。研究了雄性大熊猫(Ailuropoda melanoleuca)对同伴个体尿液气味行为反应的发育模式。结果显示,在成年雌性个体的尿液气味刺激下,雄性个体表现显著多的嗅闻行为和嗅闻/舔舐环境行为,但是嘶咬气味刺激物的行为明显减少。在雌性个体的尿液气味刺激下,不同年龄段的雄性个体行为表现不同,成年雄性个体表现较亚成年和幼年个体显著多的舔舐行为。此外,成年个体和亚成年个体均表现较多的嗅闻/舔舐环境行为,而幼年个体则无该行为表现。幼年个体较成年和亚成年个体表现显著多的气味涂抹行为,而且嘶咬气味刺激物的时间较亚成年个体显著多。幼年个体和亚成年个体对雌性和雄性个体尿液气味刺激的行为反应不存在显著差异。研究结果表明,雄性大熊猫对同种个体尿液中化学信息的行为反应呈现出年龄差异。     

半散放东北虎产仔行为的初步观察

1999年4月至2003年6月,采用随机取样法、扫描取样法和目标取样法对黑龙江东北虎林园半散放条件12只成年雌性东北虎的产仔行为进行观察。结果表明,半散放雌性东北虎的产仔行为可分为9种:站立、行走、躺卧、嗅闻、努责、梳理、生产、亲仔和舔食。雌性东北虎的躺卧和亲仔行为时间最长,分别为42.9% 和34.5% ;躺卧、努责和亲仔行为发生频率较高,分别为21.1%、16. 9% 和24.6%。单因素方差分析表明,不同雌性东北虎个体间躺卧、亲仔等行为有显著差异;不同年份雌性成年东北虎的站立、躺卧、梳理等产仔行为也具有显著差异。相关分析显示,躺卧行为与亲子行为(r_s= 0.602, P<0.05)、梳理行为(r_s=0.589,P<0.05)均呈负相关。