地方黄牛遗传改良方案调查分析

正我国黄牛资源丰富,地方品种多达5 2个,具有耐粗饲、抗逆性强、肉质细嫩等优点,是全国各地肉牛生产的主体,但与国外引进肉牛品种相比还存在一些缺陷。加快黄牛肉用遗传改良,是发展我国现代肉牛产业的基础。地方黄牛的改良方案应该依据牛品种类型、遗传改良现状和主产区气候条件情况,     

全国肉牛遗传改良计划(2021—2035年)

肉牛产业是畜牧业的重要组成部分.良种是肉牛产业健康持续发展的物质基础.《全国肉牛遗传改良计划(2011—2025年)》实施以来,构建了肉牛遗传改良体系基本框架,肉牛生产性能持续提高.为全面提高我国肉牛种业创新水平和国际竞争力,支撑和引领肉牛产业高质量发展,在前期肉牛遗传改良工作基础上,制修订本计划.     

浅析肉牛遗传育种与繁殖技术

对肉牛的遗传育种和繁殖技术进行了简要介绍,以期推动肉牛遗传育种和繁殖技术的发展。     

科技

肉牛胴体性状的遗传机制被揭示近日,牛遗传育种创新团队基于全基因组重测序数据,整合选择信号、单性状关联分析以及多性状关联分析,发现了与胴体性状相关的选择信号及候选基因,揭示了肉牛胴体性状的遗传机制,为肉牛胴体性状的选育奠定了理论基础。相关成果发表在《Genomics(基因组学)》。胴体性状作为肉牛重要经济性状之一,直接决定了牛肉的产量和质量,是肉牛育种中的关键目标。解析肉牛胴体性状的遗传机制与机理并挖掘相关的候选标记与基因,不仅可以为肉牛胴体性状的选育提供相关理论基础,还可以推动肉牛育种进展,切实地提高我国牛肉产量。目前,国内外已大量开展了对肉牛胴体性状遗传基础解析工作,捕获到NCAPG、LCORL等重要候选基因,但利用全基因组重测序数据对胴体性状遗传机制解析的分析方法仍需创新。     

利用管理方法提高牛胴体质量

本文对如何从牛场管理手段提高肉牛胴体质量进行了阐述。遗传和管理方法均会提升牛肉胴体的质量,虽然遗传手段可快速提高肉牛胴体质量,但即使不改变肉牛遗传,科学的肉牛管理方法仍会提升肉牛的胴体。反过来说,即使某一肉牛品种肉用性状较好,但忽视饲养管理,其胴体还是不能达到相应标准。管理方法中,育肥天数、分群、补饲、微量元素的使用等是主要的提高肉牛胴体的方式。     

2021年中国肉用及乳肉兼用种公牛遗传评估概要

肉牛业是畜牧业重要产业,良种是肉牛业发展物质基础.为贯彻落实《全国肉牛遗传改良计划(2021—2035年)》,宣传和推介优秀种公牛,促进和推动牛群遗传改良,定期公布种公牛遗传评估结果十分必要.     

山东省肉牛遗传改良现状分析及对策建议

山东省是全国开展肉牛改良工作较早的省份之一,先后引进多个肉牛专用品种,形成肉牛生产3大片区,推动了全省肉牛生产水平的不断提高,但是随着改良工作的深入,也出现了诸多问题及困扰。文章分析了山东省肉牛的遗传改良现状,指出肉牛遗传改良过程中存在的问题,并从6个方面提出了肉牛遗传改良的对策建议。     

新疆地区夏洛莱肉牛遗传育种与繁殖技术发展趋势探讨

夏洛莱肉牛作为一种肉质优良、生长迅速的品种,在新疆地区得到广泛的应用。近年,新疆地区的夏洛莱肉牛育种计划取得了一定的成功,但夏洛莱肉牛种质资源发展存在也存在遗传性状退化、父本品种混乱等问题。为提高其经济效益、适应性以及养殖环境的挑战,新疆地区夏洛莱肉牛的遗传育种与繁殖技术发展日益受到关注。该文简单介绍新疆地区夏洛来肉牛的遗传育种概况,在传统肉牛遗传育种与繁殖技术的基础上,探讨新疆地区夏洛莱肉牛在遗传育种与繁殖技术方面的发展趋势,为推动该地区肉牛产业的升级与发展提供有益的参考。     

肉牛的遗传育种与繁殖技术

最近几年,我国肉牛产业的发展十分迅速,肉牛的遗传育种技术以及繁殖技术都得到了很好的推广与应用,为肉牛养殖者带来了较好的效益。本文着重分析肉牛的遗传育种技术与繁殖技术。     

肉牛群体RAPD变异及其与杂种优势关系的分析

利用RAPD技术计算肉牛杂交亲本群体之间的分子遗传距离,重点研究了6个肉牛群体的遗传差异与杂交后代生产性能表现及其与杂种优势率的关系,对以后内蒙古自治区肉牛杂交改良与培育适合当地的肉牛品种提供基础资料.     

茸鹿茸重和体重性状与年龄相关的统计分析

近20年来,在开展农业部"中国鹿类资源调查"、"鹿系列标准化"等多项畜牧业重点科研课题研究,以及梅花鹿和其它种类的茸鹿品种品系选育工作中,对13种茸鹿的茸重性状和8种茸鹿的体重性状观测至今,已积累了10几年的观测数据,现将它们与年龄之间相关性的统计结果汇总报道如下.     

Effect of Gender,Body Weight and Temperature on Goose Fatty Liver Weight

The present study was designed to analyse the factors influencing fatty liver weight.Taking the overfeeding results in 2014 and the local temperature together,effects of gender,temperature and body weight on fatty liver weight were studied and the results would provide reference information for improving fatty liver production and breeding work.Totally 415 geese at 10 weeks old were overfed for 28 days.Body weight before and after overfeeding,fatty liver weights,abdominal adipose weights were measured.Blood samples of geese were collected for DNA extraction to determine the gender.The results showed that body weight before and after overfeeding and gain weight during overfeeding period were all associated with liver weight extremely significantly and the correlation coefficient were 0.40,0.62 and 0.46,respectively (P < 0.01).The body weight after overfeeding showed extremely significant effect on fatty liver weight (P < 0.01).Gender showed no significant effect on liver weight when the body weight were similar between female and male geese (P > 0.05).Effect of temperature on liver weight was extremely significant (P < 0.01).Overfeeding work should be conducted between 13.6 to 25.2 ℃ and the optimal temperature was 20.3 ℃.Higher temperature would result in reduction of fatty liver weight.In summary,temperature was a fundamental guarantee for fatty liver production and body weight was an indirect selecting index when cultivate a breed specific for fatty liver.Further,gender showed no significant effects on fatty liver weight.     

朝鲜鹌鹑体重与胸肌重的相关及回归分析

为了解朝鲜鹌鹑体重与胸肌重之间的相关性,利用SAS 9.0统计分析软件对300只38日龄朝鲜鹌鹑的胸肌重和不同日龄体重进行了相关分析和通径分析,并建立了估测胸肌重(Y)的最优回归方程。结果表明,朝鲜鹌鹑10日龄体重(X10)、17日龄体重(X17)、24日龄体重(X24)、31日龄体重(X31)、38日龄体重(X38)与胸肌重之间存在不同程度的正相关,且相关的密切程度有一定的性别差异;除母鹌鹑的10日龄体重(X10)外,公、母鹌鹑的各日龄体重与胸肌重均呈显著或极显著的正相关,提示可以通过各日龄体重的选择改进鹌鹑的胸肌重;母鹌鹑31日龄体重、公鹌鹑38日龄体重对胸肌重的直接影响最大;通过逐步回归分析建立的估测朝鲜鹌鹑胸肌重的最优回归方程为,母鹌鹑:Y=6.779+0.15X31,公鹌鹑:Y=4.524+0.14X31,2个方程的回归系数均达到极显著水平,对胸肌重的预测具有一定的应用价值。     

性别、体重及气温对鹅肥肝重的影响

本研究通过填饲试验研究体重、性别对鹅肥肝重的影响,同时结合2014年全年肥肝生产记录及当地气温资料研究气温对鹅肥肝重的影响,以期为肥肝鹅的生产和育种工作提供参考资料。选择415只10周龄健康朗德鹅,开展为期28 d的填饲试验,测定填饲前、填饲后体重,屠宰后测定肝脏重和腹脂重,采集血样,提取DNA后用于鉴定填饲鹅性别,同时收集2014年全年7 007只肥肝鹅肝脏重数据,结合每月的平均气温数据,分析气温对鹅肥肝生产的影响。结果表明,家鹅填饲前后体重及填饲期增重与肝脏重呈显著正相关,相关系数分别为0.40、0.62和0.46,均为极显著正相关（P < 0.01）,其中,填饲后体重极显著影响肥肝重（P < 0.01）;公、母鹅体重相近时性别对肥肝重无显著差异（P > 0.05）;气温对填饲效果具有极显著影响（P < 0.01）,填饲工作宜在13.6~25.2 ℃的温度下开展,20.3 ℃为最适宜填饲气温,气温越高肥肝重越小。综上所述,温度是保证填饲成功的最基本条件;可通过体重间接选育肝用型鹅品种;性别对肝脏重无显著影响。     

半胱胺对藏绵羊羔羊初生重及断奶重的影响

试验研究了半胱胺（Cs）对藏绵羊羔羊初生重及断奶重的影响。将20只妊娠（125±5）d的母羊随机分为2组（试验组和对照组）,在试验组日粮精料中添加300 mg/（kg·BW）的Cs,隔日添加1次,试验期90 d。于分娩后及时将初生羔羊称重,哺乳2个月强制断奶并称重。试验结果表明,试验组精料中添加Cs使藏绵羊羔羊初生重提高8.33%,2月龄断奶重提高13.73%。     

广西蓖麻蚕品种间全茧量，茧层量遗传分析

通过对我所保育的蓖麻品种全茧量、茧层量这两个主要经济性状进行分析,结果表明,我所保育的21个蓖麻蚕品种仍然保持基因型和表现型的多样性,仍是一个有效的品种资源。各品种对环境的抗性有差异。     

仔猪出生顺序、出生重、性别对乳头序列确定及增重的影响

主要研究仔猪出生顺序、出生重、性别等因素对乳头序列确定以及一周龄仔猪增重的影响。试验发现仔猪乳头序列的固定时间在不同窝之间存在很大差异,乳头固定受诸多因素的影响。固定过程中仔猪可能会改变偏好乳头,仔猪越频繁的更换乳头就越难固定乳头。出生重较大的仔猪初次确定偏好乳头的时间和乳头序列最终固定的时间都较短,并且增重明显较多。出生顺序、性别对乳头序列影响不显著,对仔猪增重的影响也不明显。     

Effect of Weight Gain and Subsequent Weight Loss on Glucose Tolerance and Insulin Response in Healthy Cats

The effects of weight gain and subsequent weight loss on glucose tolerance and insulin response were evaluated in 12 healthy cats. Intravenous glucose tolerance tests (IVGTT) were performed at entry into the study, after a significant gain of body weight induced by feeding palatable commercial cat food ad libitum, after a significant loss of body weight induced by feeding a poorly palatable purified diet to discourage eating and promote fasting, and after recovery from fasting when body weight had returned to pre-study values and cats were eating commercial foods. A complete physical examination with measurement of body weight was performed weekly, a CBC and serum biochemistry panel were evaluated at the time of each IVGTT, and a liver biopsy specimen obtained 2 to 4 days after each IVGTT was evaluated histologically for each cat. Mean serum glucose and insulin concentrations after glucose infusion and total amount of insulin secreted during the second 60 minutes and entire 120 minutes after glucose infusion were significantly (P > .05) increased after weight gain, as compared with baseline. At the end of weight loss, cats had hepatic lipidosis and serum biochemical abnormalities consistent with feline hepatic lipidosis. There was a significant (P > .05) increase in mean serum glucose concentration and t_1/2, and a significant (P > .05) decrease in mean serum insulin concentration and the glucose disappearance coefficient (K) after glucose infusion for measurements obtained after weight loss, compared with those obtained after weight gain and at baseline. Insulin peak response, insulino-genic index, and total amount of insulin secreted during the initial 10 minutes, 20 minutes, and 60 minutes after glucose infusion were decreased markedly (P > .05), compared with measurements obtained after weight gain and at baseline. In addition, the total amount of insulin secreted for 120 minutes after glucose infusion was decreased markedly (P > .05) in measurements obtained after weight loss, compared with those obtained after weight gain. At the end of recovery, all cats were voluntarily consuming food, serum biochemical abnormalities identified after weight loss had resolved, the number and size of lipid vacuoles in hepatocytes had decreased, and results of IVGTT were similar to those obtained at baseline. These findings confirmed the reversibility of obesity-induced insulin resistance in cats, and documented initial deterioration in glucose tolerance and insulin response to glucose infusion when weight loss was caused by severe restriction of caloric intake.     

仔猪出生顺序、出生重、性别对乳头序列确定及增重的影响

主要研究仔猪出生顺序、出生重、性别等因素对乳头序列确定以及一周龄仔猪增重的影响。试验发现仔猪乳头序列的固定时间在不同窝之间存在很大差异,乳头固定受诸多因素的影响。固定过程中仔猪可能会改变偏好乳头,仔猪越频繁的更换乳头就越难固定乳头。出生重较大的仔猪初次确定偏好轧头的时间和乳头序列最终固定的时间都较短,并且增重明显较多。出生顺序、性别对乳头序列影响不显著,对仔猪增重的影响也不明显。     

马鹿仔鹿哺乳期补饲日粮适宜蛋白质水平研究

选用 32头马鹿仔鹿随机分成 4组 ,分别饲喂 4种不同蛋白质水平日粮 (平均粗蛋白质水平分别为10 94 % ,12 85 % ,14 6 1%和 16 2 2 % )进行饲养试验及消化试验。结果表明 ,哺乳期马鹿仔鹿适宜精饲料蛋白质水平为 2 0 12 % ,适宜的日粮蛋白质水平为 14 6 1%。