林麝“控制放牧”的探讨

我国家养林麝已二十多年了,因其独居习性较难改变,迄今仍采用单一的圈养方式。最近几年,为了推动养麝业的发展,相继进行了以提高养麝的经济效益为中心的科学试验,探讨控制放牧的目的,即在于降低饲养成本,促进养麝生产的发展。     

梅花鹿的放牧

梅花鹿是一种珍贵动物,我国始养于清朝。长期以来采用圈养的方式。这种饲养方式,由于设备条件要求高,需用人员多,饲养成本贵,鹿的运动量小,对产茸有一定的影响,疾病的防治和生产操作不便,更主要的是对鹿群的发展,受到限制。因此,改圈养为放牧这     

育幼经历对圈养成年雌性大熊猫尿液皮质醇含量的影响

为研究育幼期不同的育幼方式对圈养成年雌性大熊猫Ailuropoda melanoleuca福利状况的影响情况,了解圈养育幼模式可能引发成年雌性大熊猫的应激问题,完善育幼期大熊猫的饲养管理和兽舍参数设计,提高育幼过程中圈养大熊猫福利状况,选择成都大熊猫繁育研究基地育幼期采取不同育幼方式管理的成年雌性大熊猫为研究对象,利用...     

坚持梅花鹿全年放牧掌握分娩预兆是关键

珍贵的梅花鹿,自进入圈养后,逐渐被驯化成为怕人而又近人的状态。通过人工喂养,频繁接触,仍属于胆小易惊的动物。为了更好地驯养,按人们的需要而繁殖发展,提高鹿茸产量,保证供给,支援出口。无产阶级文化大革命中,我场在各级党委的重视下,积极学习外地经验,试行“人工哺乳驯化仔鹿”,在驯化成功的基础上,利用仔带母,母带公,插群混放的方法,于1967年底将180余只圈养鹿,全部放牧于野外。相继在八年中,调供广东、甘肃及本省九个县放牧鹿600余只。梅花鹿进入全日制放牧后,母鹿受胎,仔     

卧龙大熊猫保护及研究技术的进展

对卧龙自然保护区野生大熊猫的保护与监测进行评估,阐述了卧龙圈养大熊猫人工繁殖技术的进展,包括饲养管理、种公兽的培养、人工授精、哺育期母兽管理、人工育幼、亚成体饲养管理及疾病防治等,提出了野生大熊猫的保护、监测以及圈养大熊猫人工繁殖的研究新思路。     

圈养蟒的人工饲养训练

对成都动物园2000年以来饲养过的14条蟒进行了训练.通过观察蟒的反应,采用试探、轻触、抚摩和用温热水给蟒洗浴或用温热湿巾给蟒檫拭身体等方式,让野性较大不易接近或对新饲养环境应激反应很大的蟒尽快适应人工饲养并变得更加温顺可接近.本文获得了圈养蟒接近和保定的一些经验.     

吉林省的养鹿业

吉林省的养鹿业,已有数十年的历史。早在满清时代,猎人在山上设置陷井,捕捉野鹿,进行圈养,但规模小而发展慢。解放后,国营农场逐一建立,养鹿业有了迅速发展。1954年全省养鹿 2,800余头,比解放前增加了两倍多,至 1957年末,全省养鹿总数已达 6,000余头,并出现了饲养一千头以上的大型养鹿场,预期第二个五年计划末,全省养鹿总数将达17,000多头。     

圈舍环境对圈养大熊猫发情率的影响

发情率低是圈养大熊猫Ailuropoda melanoleuca饲养的难题之一,也是制约圈养大熊猫繁育的重要因素。近年来,随着大熊猫圈养技术的不断进步,圈养大熊猫的发情率有了大幅提高,但并未达到特别高的水平。对中国保护大熊猫研究中心2006—2012年参与繁殖计划的圈养成年雌性大熊猫种群的发情率进行统计发现,2009—2012年每年雌性大熊猫的发情率高达90%以上,较2006—2008年的发情率有显著提高。2006—2012年,该大熊猫种群的饲养和管理模式、食物结构都未变化,但从2009年起圈舍环境有明显变化。经分析,该种群发情率的变化与圈舍面积、圈舍地形、圈舍植被覆盖率和植物种类等因素变化有关。本研究为提高圈养大熊猫的发情率从改善大熊猫圈舍条件的角度提供了有效的参考。     

圈养马麝(Moschus sifanicus)发情交配节律的比较研究

在1997～2000年间,甘肃兴隆山麝场的圈养马麝发情交配的时间节律保持相对年间恒定,1996年麝场进行了大规模的圈群间动物调整,导致该年的马麝圈群进入发情较迟,发情持续时间也较其他年份长。总体上,圈养马麝的发情持续时间达3个月,而66％的的发情交配发生于1个月内（从11月21日～12月21日）,发情季节（75％的发情完成累计时间）长36天。雌性圈养马麝发情的时间格局受圈养环境的季节性因子影响。饲养人员的饲养风格及各个饲养区内雌性马麝的社会行为的调节效应,各饲养区动物的发情时间格局有显著差异。年龄可影响马麝的发情交配,5．5岁龄以上的马麝发情定时更早。上一年度的繁殖成功与否和当年动物发情迟早无显著相关。野捕圈养麝群和其F1代圈群间的发情时间格局无显著差异。有较多发情周期的个体并不比发情周期仅1～2次的个体更早进入发情。     

喂哺乳仔鹿初奶可提高成活率

我场十几年来积极发展茸鹿驯养事业。通过异地引进种鹿自群繁殖和捕捉野鹿仔哺乳培育,实行舍饲与放牧相结合使茸鹿发展较快。每年圈养鹿中有部分初产,难产助产或恶癖母     

Factors influencing the levels of fatty acid synthase complex activity in fowl

There is a notable discrepancy between the FAS (fatty acid synthase) activity of four types of fowl (egg chicken, meat chicken, egg duck, and meat duck) with distinctively different body fat levels. There is a 14.8 fold difference per unit body weight between the maximum and minimum FAS activities. The three major factors affecting this discrepancy are liver weight per unit body weight, which is 2.3 times greater in meat ducks than in egg chickens, the amount of FAS protein per gram of liver, which is 1.85 times greater in meat ducks than in egg chickens, and the FAS specific activity in meat ducks, which is 3.5 times greater in meat ducks than in egg chickens. Within the same species of egg chickens, the abdomen fat per kg of body weight at 470 days after egg production is 66 times greater than 90 days before egg production and the liver FAS activity is increased 9.6 fold. The 9.6 fold FAS activity increase resulted from an increase in the specific activity, since the liver weight per kilogram of body weight remained constant at approx. 20 grams and the FAS weight per gram of liver also remained constant at approx. 4.5 mg. This shows that the control of the basic FAS activity level which is closely related to the level of body fat does not mainly arise from genetic control. For the same kind of fowl, the control of the basic FAS activity level occurs after gene expression. It is suggested that control may be imposed in the folding phase when new peptides give rise to functional proteins.     

Effect of different dietary energy and protein sources on antioxidant status,fresh yolk fatty acid profile and microstructure of salted yolks in laying ducks

The study investigated whether different dietary energy and protein sources affect laying performance, antioxidant status, fresh yolk fatty acid profile and quality of salted yolks in laying ducks. In all, 360 19-week-old Longyan ducks were randomly assigned to four diets in a factorial arrangement (2×2). The four diets consisted of two energy sources, corn (CO) or sorghum (SO) and two protein sources, soybean meal (SM) and rapeseed meal with corn distillers dried grains with solubles (RMD), and each treatment contained six replicates of 15 birds each. The experimental diets were isocaloric (metabolizable energy, 10.84 MJ/kg) and isonitrogenous (CP, 17%). The results showed that egg production, average egg weight, egg mass and feed conversion ratio were not affected by diets (P>0.05). Plasma contents of reduced glutathione (GSH), GSH/oxidized glutathione and total antioxidant capacity were lower (P<0.05) in ducks fed the RMD diets compared with those fed SM diets with a substantial increase (P=0.006) in plasma content of malondialdehyde (MDA). Egg yolks from ducks fed SO diets had higher proportions of polyunsaturated fatty acids (PUFA) and lower saturated and monounsaturated fatty acids compared with CO diets (P<0.001). Similarly, ducks fed RMD diets had a higher content of PUFA and n-6/n-3 ratio in fresh yolks (P<0.001), and increased salted yolk MDA, carbonylated proteins content and incidence of hard salted yolks (P<0.05) compared with SM diets. Scanning electron microscopy showed that salted yolks contained rougher polyhedral granules and fewer fat droplets, and were surrounded with a layer of bunchy fibers in ducks fed SO+RMD than those fed CO+SM diet. In conclusion, the current study showed that feeding laying ducks with diets containing SO or RMD reduced antioxidant capacity and increased egg yolk concentrations of PUFA. It appeared that egg yolks from ducks fed these diets were more sensitive to lipid peroxidation and protein oxidation during salting, and reduced the quality of salted yolks.     

Egg size, first instar behaviour and the ecology of Lepidoptera

There is striking variation in egg size among Lepidoptera. Part of the explanation could be a link between egg size and larval feeding ecology.
The relationship between absolute egg size and aspects of feeding ecology for different Lepidoptera families from different temperate regions is examined. Species that overwinter in the egg stage have larger eggs. There are significant differences in egg size with respect to feeding specificity but different families show different patterns. Woody plant feeders have larger eggs than herb feeders. There is little effect of proximity of the egg to the plant part that is eaten.
Patterns in the behaviour and survival of newly hatched larvae of 42 spp. of British Lepidoptera and their relationship to egg and larval size and to food plant characteristics are examined. Patterns in egg size with respect to feeding ecology are similar to those described above. There is a strong correlation between egg size and the size of newly hatched larvae. Newly hatched larvae survived for a mean of 1–20 days without food. Survival is not correlated with larval weight. Grass feeders survive longer than herb and woody plant feeders; the species surviving the longest feeds on lichens. Newly hatched larvae moved at a mean speed of 0.7-267.8 cm h^-1. Speed is not correlated with larval weight or survival time. Grass feeders move faster than woody plant feeders which, in turn, move faster than herb feeders. Woody plant feeders tend to move upwards, grass feeders downwards and herb feeders both upwards and downwards. The proportion of larvae silking is negatively correlated with larval weight.
The strong links between egg size and larval feeding ecology and between feeding ecology and larval behaviour are discussed. It is surprising that larval body size does not appear to constrain the speed of movement, nor tolerance to starvation.     

Heterogeneity of serum, egg amylase and egg lysozyme in the interspecific hybrids of ducks

Polymorphism of serum and egg amylase by means of horizontal agarose gel electrophoresis and egg lysozyme by means of horizontal starch gel electrophoresis in Pekin, Muscovy ducks and their interspecific hybrids was studied. In the interspecific hybrids of ducks the codominant type of heredity of serum, egg yolk and egg white amylase isozymes, as well as egg white lysozyme, were found.     

Salinity as a constraint affecting food and habitat choice of mussel-feeding diving ducks

Observations of freshwater drinking in Eiders feeding primarily on mussels led us to hypothesize that the highly saline sea water enclosed in mussels could cause salt-related dehydration problems in the ducks, since they consume entire mussels. The proportion of sea water increases with increasing mussel size. Smaller duck species are more sensitive to the higher salt content of larger mussels than are larger ducks; however, salt stress may be avoided by feeding in habitats with lower salinity, by feeding on less salty food items, by utilizing smaller mussels, by drinking fresh water, or by employing low energy foraging techniques. A possible evolutionary strategy for solving the salt problem might be to increase body mass, enabling ducks to utilize larger mussels without passing an upper salt consumption limit. At the same time, foraging on larger mussels is more economical. Although large size facilitates the utilization of brackish and marine environments, it may be selected against in ducks breeding in fresh water, where fish competition may reduce optimal food item size. In conclusion, salinity is an important habitat barrier in both breeding and overwintering diving ducks, but there are various ways of crossing this barrier. To understand better how ducks utilize their habitats, however, it is necessary to measure habitat salinity levels and the size of both ducks and their preferred and less-preferred food types.     

Transmission dynamics of the recently-identified BYD virus causing duck egg-drop syndrome

Baiyangdian (BYD) virus is a recently-identified mosquito-borne flavivirus that causes severe disease in ducks, with extremely rapid transmission, up to 15% mortality within 10 days and 90% reduction in egg production on duck farms within 5 days of infection. Because of the zoonotic nature of flaviviruses, the characterization of BYD virus and its epidemiology are important public health concerns. Here, we develop a mathematical model for the transmission dynamics of this novel virus. We validate the model against BYD outbreak data collected from duck farms in Southeast China, as well as experimental data obtained from an animal facility. Based on our model, the basic reproductive number of BYD virus is high (R(0) = 21) indicating that this virus is highly transmissible, consistent with the dramatic epidemiology observed in BYDV-affected duck farms. Our results indicate that younger ducks are more vulnerable to BYD disease and that ducks infected with BYD virus reduce egg production (to about 33% on average) for about 3 days post-infection; after 3 days infected ducks are no longer able to produce eggs. Using our model, we predict that control measures which reduce contact between mosquitoes and ducks such as mosquito nets are more effective than insecticides.     

Factors affecting reproductive performance in captive Mallard ducks

Propagation of wild-strain Mallards (Anas platyrhynchos) in captivity is hindered by low egg fertility. Therefore, we studied the effects of captivity, age, mate choice and isolation on reproductive parameters of Mallards. Captive drakes had smaller immature testes than free-flying Mallard drakes. Captive yearling ducks weighed less than adult ducks at the beginning of the breeding season, but no differences were found between their initial clutch size, egg volume or number of clutches laid. Yearling pairs had lower egg fertility (7%) than adult pairs (80%). Egg fertility was higher (51 vs 21%) in self-chosen pairs than in randomly assigned pairs. Isolation of ducks, however did not influence egg production.     

Comparative liver transcriptome analysis of duck reveals potential genes associated with egg production

Molecular Biology Reports - Molecular studies on egg production in ducks were mostly focused on brain and ovaries as they are directly involved in egg production. Liver plays a vital role in...