大熊猫分娩活动的观察

本文报道了对6只大熊猫(Ailuropoda melanoleuca)14次分娩活动的观察结果。大熊猫分娩前48小时至24小时即出现将分娩的征兆,其总产程约14至22小时左右。分娩时为纵向胎向;多数为胎上位,个别为胎侧位;胎势为前肢和头颈靠紧并伸直,尾、后肢并紧且自然伸直;多数胎儿为头、前足先露出,即前躯前置;少数为尾、后足、臂先露出,即后躯前置。     

胎仔数与父本缺失对棕色田鼠幼仔体重发育的影响

室内饲养条件下,测量了出生后不同发育阶段棕色田鼠Microtus mandarinus的体重,并探讨了胎仔数(分别为1只、2只、3只和4只)及父本缺失(母鼠单独抚育)对幼仔体重发育的影响.结果表明,棕色田鼠出生后第一周体重的瞬时生长率最高,此后逐步下降;出生后28～35 d,体重增益最大(P<0.05).出生后7 d,不同胎仔数的体重没有明显差异,但至断乳时(出生后21 d),胎仔数为2只的幼仔平均体重明显高于其它胎仔数的平均体重(P<0.05).与双亲抚育相比,母鼠单独抚育的幼仔在断乳时的体重明显下降(P<0.05).这些结果说明,哺乳期内棕色田鼠幼仔的体重发育与胎仔数有关.由于棕色田鼠是单配制,双亲育幼,父本雄鼠的缺失减少了亲本投资,影响了幼仔的身体发育.     

野化培训大熊猫幼仔第一阶段的活动变化研究

2011年8月—2014年8月,利用红外视频监控系统结合现场观察,在中国保护大熊猫研究中心卧龙核桃坪野化基地对野化培训第一阶段的7只大熊猫Ailuropoda melanoleuca幼仔的活动变化进行研究,采用瞬时扫描取样法收集了母幼距离、幼仔活动空间位置和行为等数据。研究结果发现:(1)母幼距离随着幼仔月龄的增长而增加,到幼仔爬树时母幼距离达到最高点,11~12月龄后出现下降的趋势。(2)野化幼仔随着月龄增长在母兽怀中的时间呈递减趋势;幼仔在地面的时间表现为未能独立活动时递增,5~9月龄时递减,其后14~15月龄时递增的变化规律;幼仔在树上的时间呈现5~10月龄时递增,接着稳定在一个较高的值,到14月龄时递减的波动;幼仔在母兽怀中(n=2,P0.05)和在地面的时间(n=5,P0.01)均与其在树上的时间呈负相关。(3)在活动时间分配上,幼仔平均用于休息的时间为所有行为时间的90.1%±4.1%,平均用于活动的时间为9.3%±3.9%,平均用于觅食的时间为0.6%±0.4%。     

甘肃莲花山暗绿柳莺的孵卵行为

2001年5～7月,在甘肃省莲花山自然保护区对暗绿柳莺Phylloscopus trochiloides的孵卵行为进行了初步研究.结果 表明,孵化期内雌鸟日活动期长度平均为(848.5±14.8) min (n=17),每天离巢(16.0±3.0)次(n=15),每次离巢时间为(12.3±5.0) min (n=251),每次在巢时间为(43.6±21.9) min (n=236),在巢率为(78.8±2.4)%.雌鸟在巢时卵温平均为(31.3±3.5)℃ (n=10646),离巢时卵温平均为(26.6±4.8)℃ (n=2876);夜晚的平均卵温为(30.6±3.5)℃ (n=9239).孵卵温度在孵卵期有逐渐上升的趋势.     

甘肃莲花山淡眉柳莺的繁殖记录及其孵卵行为

2001年6～7月,在甘肃省莲花山自然保护区记录了淡眉柳莺(Phylloscopus humei)繁殖,研究了其孵卵行为。结果表明,窝卵数为(4.3±0.5)枚(4～5,n=4),卵的大小为(14.0±0.4)mm×(11.2±0.4)mm(n=17)。育雏期为(13.8±0.5)d(13～14,n=4)。孵化期内雌鸟日活动期的平均长度为(833.2±40.0)min,平均每天离巢(46.6±12.2)次(n=27),每次离巢时间为(5.3±2.8)min(n=1435),每次在巢时间为(12.7±7.5)min(n=1409),在巢率为72.4%±11.6%(n=21)。雨天在巢和离巢的时间与晴天有显著差异,晴天在巢率为71.5%±12.1%(n=13),雨天在巢率为75.1%±9.0%(n=8)。在整个孵卵期间所有记录到的卵温平均为31.2℃(49066min内连续记录58879次)。雌鸟每次离巢,卵温平均下降(9.4±3.4)℃(n=1450)。     

英国惠普斯耐德獐的育幼行为(英)

1993年5～8月在英国惠普斯耐德野生动物园半自然条件下研究了獐（Hydropotesinermis）的单亲育幼行为。描述了母幼獐建立关系，母獐的探访和育幼行为，授乳行为，舔犊行为以及母幼间距离等。研究结果表明，母獐昼夜间仅探访幼兽4～5次。初生獐寻找乳头时往往寻错位置，找向母獐的前胸和颈区。在幼獐出生后的早期，哺乳行为的启动是由母獐启动的，但幼獐一周龄后即为启动者。平均哺乳时段为48．2±10．2s。母獐的舔犊行为常与哺乳同时发生，舔犊的位置最常见于幼獐的头部（62．7％），其次是肛殖区（13．9％），再是背部（8．4％）、胁部（7．2％）、胸部（5．6％）和颈部（2．1％）。此外，还讨论了母兽对不同性别的幼獐的投资的差异及其生物学意义。     

布氏田鼠种群繁殖特征研究

越冬田鼠每年可繁殖3胎,第1胎幼仔生于4月下旬到6月上旬,第2胎幼仔生于5月中旬到7月上旬,第3胎幼仔生于6月中旬到7月下旬。种群上升年份(1987)各胎幼仔出生高峰比1988年的提前10天左右。1987年越冬鼠第1胎集中,如4月下半月,1987年怀孕率为100%,而1988年只有44.44%。6月上半月以前越冬鼠为种群繁殖的主体,而后被当年生鼠所取代。从4月下半月到9月上半月共出生4批同龄群。K₁和K₂组生长发育旺盛,当年就参加种群繁殖,可怀孕1—3胎。K₃组生长发育较慢,当年并不性成熟,越冬后性成熟成为种群越冬鼠的主体。K₄出生晚,数量少,很少能度过漫长寒冷的冬季而成为种群的无用或潜在的繁殖力量。本文还发现越冬鼠的平均胎仔数显著高于当年鼠：种群上升年份越冬鼠平均胎仔数高于种群下降年份,而当年生鼠的平均胎仔数年度间则没有显著性差异。     

圈养大熊猫同时哺育双胞胎行为观察

2003 年,圈养大熊猫“梅梅”首例哺育成活一胎二仔,通过对其近半年的育幼行为观察,结果发现:1) 母兽主要以同时衔2 仔、同时衔和抱2 仔二种方式将幼仔抱入怀中哺育;60 d 内, 育幼姿势以坐位为主,倦卧其次, 其它姿势更少, 其中坐位随日龄增加逐渐减少, 倦卧变化不大。2) 母兽活动时间在产仔当天最多, 之后显著下降并维持在35.2 ± 0.6% 的低水平, 47 d 后再缓慢上升到108 d 后的54.8 ± 0.9% 。3) 双胞胎幼仔间哺乳的日均次数和时间无显著差异。4) 7 d 内2 幼仔“仔在母身上” 的时间占100%, 21 ～ 23 d 后显著减少, 而“母体盖仔”、“仔在母身边”和“母仔自然分离”的时间显著增加, 但“母体盖仔” 的时间在32 d 左右后又显著减少;双胞胎分别在与母兽的此四种位置变化的时间上无显著差异。5) 母兽的活动、幼仔哺乳日均次数、“母仔自然分离”在全天的日均时间分布有峰、谷变化。6) 随幼仔活动能力的逐渐增强,幼仔离“育幼窝”的距离也逐渐增加,双胞胎幼仔离“育幼窝”的远近也有差别。7)母兽分别与其雄性双胞胎幼仔玩耍的时间有显著差异,而两幼仔自玩的时间无差异,此两双胞胎自玩和一起玩耍所用时间远大于分别与母兽玩耍的时间。该研究丰富了大熊猫育幼行为内容,并为以后的大熊猫双胞胎育幼提供了可供参考的行为资料。     

驯养林麝(Moschus berezovskii)的繁殖节律:分娩定时及同步化

于2013年3—10月在四川马尔康麝场开展,记录了178例驯养林麝(Moschus berezovskii)的分娩,分析了其分娩定时、同步化及关键影响因素。结果表明,马尔康麝场的驯养林麝分娩发生于5—7月间,分娩期长达66d,平均分娩时间为5月25日(17.60±0.98,n=178),分娩季节(75%的分娩完成时间)长22d(即5月7日至5月28日间)。马尔康林麝分娩的强季节性是对当地季节性水热条件和食物资源的适应。驯养林麝的分娩时间与其年龄的相关不显著(r=-0.121,P=0.1060.05),虽亚成体雌麝(2—3岁)的分娩时间(5月26日,18.81±1.47,n=75)有迟于成体麝((4—9岁)(5月24日,16.97±1.41,n=95)和老龄雌麝(≥10岁)(5月21日,13.63±2.24,n=8)的趋势,但差异未达显著水平(P0.05)。此外,麝场各饲养区内的雌麝分娩时间格局无显著差异(P0.05),泥地基底的改装圈舍内的雌麝分娩(5月22日,15.31±1.48,n=62)略早于砖地基底的原装圈舍雌麝分娩(5月26日,18.82±1.27,n=116),差异未达显著水平(P0.05)。     

姜黄素预处理对沙漠干热环境猪腹部枪弹伤模型生存时间的影响

目的:探讨姜黄素预处理对沙漠干热环境腹部枪弹伤动物模型生存时间的影响。方法:将24头长白仔猪随机分为2组(n=12):姜黄素预处理组和对照组。姜黄素预处理组给予长白仔猪姜黄素100 mg/kg拌料饲养,每天1次,连续7天,对照组给予常规饲料喂养。第8天,将两组猪放入西北特殊环境人工实验舱内,设置环境温度(40.5±0.5)℃,相对湿度(10±2)%,禁食水,放置3小时后建立腹部枪弹伤模型,模型成功后继续放在沙漠干热环境中,每10分钟检测体温变化,并计算长白仔猪的存活时间。结果:姜黄素预处理组平均存活时间为(85.27±2.39)min,对照组的动物模型平均生存时间为(60.10±3.25)min,姜黄素预处理组的生存时间平均比对照组延长约25 min,两组的Kaplan-Meier生存曲线经Log Rank检验具有显著性差异(P0.01)。建立腹部枪弹伤模型后,在相应时间点,姜黄素预处理组的体温明显低于未处理组(P0.01),姜黄素预处理组70 min时的体温与对照组50 min体温比较差异无统计学意义(P0.05)。结论:姜黄素预处理可明显提高干热环境下猪腹部枪弹伤模型的生存时间,体温升高可能是反映干热环境腹部枪弹伤后病程进展的重要指标。     

Dermatoglyphic variation and weight and length at birth

Relationships between dermatoglyphic variables, including finger ridge counts and finger, palmar, and plantar pattern intensities, and weight and length at birth, were tested in a sample of 184 boys and 202 girls from Warsaw schools. No convincing evidence for such relationships has been obtained from the results of correlations and one-way analysis of variance, although there are indications that some palmar traits may be related to length at birth in females. The data agree with the common belief that birth weight and birth length are mainly determined by influences operating in later stages of pregnancy, that is, after the 20th gestational week.     

一类个体寿命有限的纯生过程

讨论了一类个体的寿命有限且一生分为若干个阶段的纯生过程 （ｐｕｒｅ ｂｉｒｔｈ ｐｒｏ－ｃｅｓｓ），其中每个阶段的存活率，繁殖率，其繁殖符合 Ｐｏｉｓｓｏｎ过程．证明了其小群体的繁衍分布服从分布；ｉ和ｊ两个不同阶段繁殖的时间间隔之比的密度函数为Ｆｉｂｏｎａｃｃｉ过程［４］中总体的期望数和寿命与指数分布有关等性质．     

Pelvic sexual dimorphism and relative neonatal brain size really are related

Primate species in which the neonatal brain size is large relative to the birth canal tend to have more sexually dimorphic pelves: this is a classic comparative relation, discovered by Schultz and Leutenegger. The original work did not correct for phylogenetic nonindependence of the data points; it only partly corrected for body size; it used ratios in both variables, and the size of the female pubis featured in both x- and y-variables. A recent publication by Tague placed a question mark over the validity of the relation. I therefore retested it, correcting for all four statistical defects. A strongly significant statistical relation exists. © 1995 Wiley-Liss, Inc.     

Variation in size at birth and cigarette smoking during pregnancy

The influence of cigarette smoking during pregnancy and other familial factors on size at birth and gestation length is investigated among 458 births to 227 mothers living in a suburban community in the U.S. In this sample, 56% of the births were to mothers who reported not smoking during the pregnancy and 35% were to mothers who reported smoking 20 cigarettes or less. Multiple stepwise regression analysis was employed to examine the influence of cigarette smoking after statistical adjustment for such social and biological characteristics of the family as parents' sizes, education, income, and aspects of mother's reproductive history. After correction for significant social and biological characteristics, smoking status was a significant contributor to birth weight variation. In fact, cigarette smoking had the next-largest partial correlation coefficient (r = -0.26) second to gestation length. Birth length is also negatively associated with cigarette smoking, though not so strongly as is birth weight. The reduction in birth lengths can be attributed to the reduction in birth weights. Gestation length was not associated with cigarette smoking in this sample. The analysis of collinearity between smoking status and the other independent variables indicates that the effect of smoking appears to be independent of interrelationships among the independent variables.     

The relationship between maternal characteristics, birth weight and pre-term delivery: evidence from Germany at the end of the 20th century

Using data from a sample of German women, this paper analyzes the relationship between maternal characteristics and infants' birth weight and pre-term delivery. Besides typical epidemiological factors that influence the weight of infants, such as the gestational age and maternal BMI at the beginning of the pregnancy, we find a West--East gradient. Within West Germany, there is a small North-South gradient in birth weight, with larger birth weights in the north. Better educated mothers give birth to heavier babies and have a somewhat decreased risk of pre-term delivery. Income plays a minor role, while occupational status is not associated with the weight of infants at all.     

Selenium in placenta predicts birth weight in normal but not intrauterine growth restriction pregnancy

Placental selenium, lead and cadmium concentrations were determined in a group of pregnancies with birth weight appropriate for gestational age and in a group of intrauterine growth restriction cases. Following adjustment for a number of confounding variables, selenium was found to be a significant predictor of newborn weight only in the group of pregnancies with birth weights appropriate for gestational age. Placental lead and cadmium levels were not associated with birth weight in either group.     

α-氯代醇对雄性大仓鼠的不育效果观察

α－氯代醇对雄性大仓鼠的不育效果观察ＴＨＥＳＴＥＲＩＬＥＥＦＦＥＣＴＯＦＡＬＰＨＡ┐ＣＨＬＯＲＯＨＹＤＲＩＮＯＮＣＲＩＣＥＴＵＬＵＳＴＲＩＴＯＮ大仓鼠（Ｃｒｉｃｅｔｕｌｕｓｔｒｉｔｏｎ）是我国华北平原、关中平原及东北平原重要农田害鼠。由于它对抗凝血...     

Study of placenta of children born with congenital malformations

The malformations in this study were observed in a series of 279,642 consecutive births of known outcome registered in our Registry of congenital anomalies. For each case, more than 50 factors included in the registration forms were studied. One of the factors studied was the placenta. For each malformed child, a control was chosen. Cases with maternal known factors impairing placenta function, i.e. vasculopathy and diabetes, were excluded. In each category of malformations studied, the malformed children were divided into isolated and non-isolated (multiple malformed) cases. The weight of placenta of isolated cases was not lower than the weight of placenta of the controls. In contrast, the weight of placenta of the cases with non-isolated malformations was lower than the weight of placenta of the controls and of the isolated cases, for all categories of malformations but gastroschisis and omphalocele. The mean weights at birth of the cases with multiple malformations were also lower than those of the controls. The human placenta discounts a principal functional part, the maternal blood in the intervillous space. Congenital malformations may interact with this function.     

Demography of Propithecus verreauxi at Beza Mahafaly,Madagascar: Sex ratio,survival, and fertility, 1984–1988

Eighty-five sifakas (Propithecus verreauxi) have been captured, marked, released, and monitored between September 1984 and August 1988 at the Beza Mahafaly Special Reserve in southwest Madagascar. Estimates are presented of the age and sex structure of this population and of age-specific fertility and survival. Using data from this and other studies, it is shown that sifaka tertiary sex ratios do not depart significantly from 50:50, but that they do differ significantly from those of haplorhine primates, which have strongly female-biased tertiary sex ratios. Two demographic mechanisms that could give rise to this distinction are considered: 1) intermittently male-biased birth cohorts among sifakas and 2) different patterns of survivorship in haplorhines and sifakas.     

Human sex ratio at birth in South West Nigeria

BACKGROUND:

Human sex ratio at birth differs from one population to the other. This variation has been attributed to cultural practices, seasonal variation, small-family size policy and sex selective technology. Information on secondary sex ratio in Nigeria is limited.

AIMS AND OBJECTIVE:

To analyzed human sex ratio at birth for samples of the Nigerian population in 4 urban settings in Southwest Nigeria, in order to know the trend and to compare the findings with those of previous reports.

MATERIALS AND METHODS:

Data were collected from Obafemi Awolowo University (OAU) teaching hospital at Ile Ife and Wesley Guild hospital at Ilesa, Osun state; General hospital at Ogbomoso, Oyo state and Ekiti state specialist hospital at Ado-Ekiti, Ekiti state. The data consisted of 35 209 live single births recorded between 1995 and 2004. Each set of data was analyzed to determine the sex ratio by year, month and quarterly values. Chi-square analysis was used to determine the deviation of the sex ratios for the years from the average value.

RESULTS:

The annual average ratios of 104.7:100, 102.8:100, 98.9:100 and 100.8:100 were recorded for OAU teaching hospital, Wesley Guild Hospital, General Hospital and Ekiti State specialist hospital, respectively. When pooled together, the average ratio was 102.7:100. This shows some bias for male births. Data also indicates more male birth in the rainy season, suggesting a seasonal variation of sex ratio.

CONCLUSION:

These findings are representative of the populations in southwest Nigeria and are comparable to values obtained for other regions in Nigeria and other populations of African origin.