搜索结果: 106-120 共查到“知识库 动物生长发育学”相关记录444条 . 查询时间(0.907 秒)
Estimation of Weaning Age Effects on Growth Performance in Berkshire Pigs
Average Daily Gain, Empirical Relationship, Weaning Age, Random Effects
2016/5/9
Analysis for back fat thickness (BFAT) and daily body weight gains from birth to the end of a performance test were conducted to find an optimal method for estimation of weaning age effects and to asc...
Regulation of S100G Expression in the Uterine Endometrium during Early Pregnancy in Pigs
Pig, Uterus, S100G, SCNT, Calcium
2016/5/9
Calcium ions play an important role in the establishment and maintenance of pregnancy, but molecular and cellular regulatory mechanisms of calcium ion action in the uterine endometrium are not fully u...
本实验选取40 份不同胎龄的牦牛肺脏样本,通过组织学和组织化学的方法对牦牛肺发育过程进行研究,旨在为发育生物学提供形态学资料。结果表明,牦牛胚胎肺发育可分为5 个时期:(1)胚胎期(30 ～ 50 d),胚胎出现肺芽,其分支形成主支气管,进一步分出叶支气管,上皮均为假复层柱状上皮; (2) 假腺期(50 ～120 d),支气管树发育明显,末端终蕾结构似腺体,为假复层柱状上皮;(3)小管期(120 ...
草兔线粒体基因组全序列及其系统发育关系分析
线粒体基因组 系统发育分析 草兔
2016/7/19
草兔(Lepus capensis)在我国数量多,分布广,但人们对草兔的系统地理学、草兔与其他兔类的系统发育关系了解不多,其亚种水平的分类也长期存在争议。本研究通过LA-PCR 技术对草兔线粒体基因组全序列进行PCR 扩增、序列测定和分析,并基于线粒体基因组12 个蛋白质编码基因10 776 bp的核苷酸序列,采用贝叶斯法(BI)和最大似然法(ML)构建哺乳纲(Mammalia) 灵长总目(Eua...
珠江口棘头梅童鱼耳石的生长特性
棘头梅童鱼 耳石生长 生长关系
2012/3/22
研究了棘头梅童鱼(Collichthys lucidus)耳石的形态参数、生长特性及其与鱼体生长的关系,选用左矢耳石为研究对象,用直线、对数、多项式、幂函数和指数函数拟合矢耳石各参数的生长关系式,依据耳石日轮鉴定了日龄。结果表明,体长范围为29.8～104.0 mm的棘头梅童鱼矢耳石的长直径随鱼体生长而增大,但短直径与长直径的比值以及长直径方向上的短半径与长半径的比值则基本稳定。矢耳石的长、宽和重...
环境因子对养殖条件下出蛰的东北林蛙存活和生长的影响
东北林蛙 出蛰 环境因子 成活率
2012/3/22
实验通过在设施环境下和控制条件下,研究出蛰温度、湿度及风速3种环境因素对林蛙生长和存活的影响,目的在于探索东北林蛙(Rana dybowskii)适宜的出蛰环境。结果表明:温度是影响东北林蛙出蛰存活和生长的重要因素,当出蛰温度低于16℃,东北林蛙有较高的成活率,而出蛰温度高于20℃,则会引起70%以上的东北林蛙死亡,出蛰期间温度缓慢提高有利于东北林蛙生长和存活。东北林蛙出蛰期间适宜的湿度在80%以...
耳螺的研究现状与展望
耳螺 软体动物 进化 研究进展
2012/3/23
耳螺(Ellobiid)是一类特殊的原始有肺类软体动物,大多嗜盐,主要分布于海陆过渡区的高潮带和潮上带。耳螺在软体动物进化史上具有特殊地位,并且因其对环境变迁和人为干扰十分敏感,可作为环境评估的重要指标种。过去2个多世纪,众多学者已经对耳螺的形态学、解剖学、分类学和生态学等开展了系统的研究。本文概述了耳螺研究的3个阶段:起步阶段(18世纪末至20世纪30年代初)、发展阶段(20世纪30年代初至70...
近年鲟鱼人工繁殖技术促进了鲟鱼养殖业的发展,但在选育初期未对后备亲鱼进行遗传背景分析,为了抑制种质资源退化和防止近交衰退,繁育场需要对现有后备亲鱼进行遗传背景分析。本文利用线粒体控制区(D-loop)部分序列对4种养殖鲟鱼后备亲鱼群体(共120个样本)的遗传多样性进行了分析。研究发现不同种鲟鱼D-loop部分序列长度不同(451～469 bp),种间存在1～18 bp的插入/缺失,种内无插入/缺失...
2011年8月PNAS刊登了李枢强研究员领导的无脊椎动物学研究组与斯洛文尼亚合作团队的研究结果“Eocene habitat shift from saline to freshwater promoted Tethyan amphipod diversification”(August 15, 2011；http://www.pnas.org/content/early/2011/08/11/1...
Melatonin Induced Changes in Specific Growth Rate, Gonadal Maturity, Lipid and Protein Production in Nile Tilapia Oreochromis niloticus (Linnaeus 1758)
Melatonin, Gonad Structure, GSI, Condition Factor, SGR%, Biochemical Changes, Oreochromis niloticus
2016/5/9
We have investigated the effect of melatonin (MLT) on specific growth rate (SGR% day−1), condition factor (k), gonado-somatic-index (GSI), histological structures of gonads, serum as well as gon...
Effects of Squid Ink on Growth Performance, Antioxidant Functions and Immunity in Growing Broiler Chickens
Squid Ink Antioxidant Ability Immune Function Growth Performance Broilers
2016/5/9
This study was conducted to explore the effects of squid ink on growth performance, immune functions and antioxidant ability of broiler chickens during a period of six weeks. Either sex Arbor Acres br...
Growth Performance, Carcass Traits and Meat Quality in Broilers, Fed Flaxseed Meal
Flaxseed Meal Broiler Growth Performance Alpha-linolenic Acid
2016/5/9
The effect of flaxseed meal on broiler performance, carcass characteristics, alpha-linolenic acid contents, and organoleptic characteristics of chicken meat was studied during a 42 day experiment. Bro...
Global pork markets are becoming more competitive, riding the wind of the bilateral free trade agreement. China is the world’s largest pork producer with nearly 50% of the world’s total production. Ch...
Early Growth Response of Broilers to Dietary Lysine at Fixed Ratio to Crude Protein and Essential Amino Acids
Lysine Crude Protein Essential Amino Acid Early Growth Response Broilers
2016/5/9
The effects of dietary lysine (Lys) at a fixed ratio to crude protein (CP) and essential amino acids (EAA) on early growth response of broilers were studied. Four diets were formulated to contain simi...
Effect of MEM Vitamins Supplementation of In vitro Maturation Medium and In vitro Culture Medium on the Development of Porcine Embryos
Porcine Embryo Development Blastocyst Vitamins
2016/5/9
This study was carried out to examine the influence of minimum essential medium (MEM) vitamins supplementation to in vitro maturation medium and in vitro culture medium on the development of porcine e...