繁育小知识

凡是生物都能把本身的形态和性质传给它的后代，这就叫做遗传。选择优良的品种和采用科学的育种方法，是获得优良仔犬的关键。     

Basic hematologic values in gilts of the Large White breed and their crosses with the Landrace breed

The basic haematological parameters (erythrocytes, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, leucocytes, leucocyte type) were determined in 83 clinically relatively healthy gilts of the Large White breed and 85 gilts--crossbreds with the Landrace breed, at the age of five to seven months. The results were subjected to statistical processing. The erythrocyte counts are significantly higher in the crossbreds than in the gilts of the LW breed. The basic erythrocyte values, dependent on the number of erythrocytes, are significantly higher in the gilts of the Large White breed. The leucocyte counts correlate with those of the gilts of the same age; however, they are higher than in the adult sows. As a result of the evaluation of the leucocyte type, the gilts at the age of five to seven months were found to have a white blood picture of lymphocytic type. Further, a shift towards younger forms of cells of the granulocytic series was observed even in clinically relatively healthy animals.     

Development of the Polypay breed of sheep

Development of the Polypay breed was undertaken to combine into a composite breed the potential for greatly increased reproductive capacity along with desirable growth rate and carcass quality. Four breeds were selected for the foundation of the new breed--the Rambouillet and the Targhee for hardiness, large body size, long breeding season, herding instinct and fleece characteristics; the Dorset for carcass quality, milking ability and long breeding season and the Finnsheep for early puberty, early postpartum fertility and high lambing rate. Dorset X Targhee and Finnsheep X Rambouillet matings were first made in 1968, and reciprocal Dorset-Targhee X Finn-Rambouillet matings were initiated in 1969. Beginning in 1970, the respective two-breed crosses and the four-breed cross (Polypay) were each mated inter se and selected, along with straightbred Rambouillets and Targhees, for lamb production when given two opportunities to lamb/year. Initial comparisons among straightbreds and inter se mated groups showed few important differences in meat-type body conformation, body condition or growth rate, but superior annual reproductive performance by Polypays. Fertility of Polypays at 1 yr of age was high and comparable to that of the Finn-Rambouillets. Response of Polypays to twice-a-year lambing was superior to responses of Rambouillets. Targhees, Dorset-Targhees or Finn-Rambouillets. The 1974 to 1975 annual production of young Polypays was about 13% more lambs weaned than from Finn-Rambouillets and 18% more weight of lamb weaned than from Dorset-Targhees, the best of the other groups for these traits. The current (1979 to 1981) reproductive performance of Polypay ewes selected for high once-a-year lambing rate under typical range management conditions is very competitive with that of 1/2 Finn crossbreds. Annual production of mature Polypays on the twice-a-year lambing schedule was 1.78 lambs weaned and 58.6 kg of lamb weaned/ewe put into fall breeding.     

Population structure of the Japanese Brown breed

SUMMARY: The population structure of the Japanese Brown in Kumamoto Prefecture was investigated with pedigree analysis. Two hundred heifers were randomly sampled, in 1960, 1970, 1980, and 1990. Population genetic parameters, i.e. F-statistics, index of subdivision, generation interval, effective population size, and effective number of sires, were estimated. The effective number of sires decreased, most dramatically, from 1970 to 1980. The average inbreeding coefficient (F(IT) ) increased, from 0.64% in 1960 to 5.43% in 1990. F(ST) increased in parallel with F(IT) , while F(IS) remained low. From 1960 to 1980, the index of diversity showed a decreasing trend, but this improved a little, with the index at 1.1 in 1990. The generation interval tended to be longer year by year, and was 5.52 during 1980-90. On the other hand, N(e) decreased, from 724.6 before 1960 to 40.1 at the present. The population structure of the Japanese Brown is not problematical at present, when considering F(IT) , but the irreversible inbreeding coefficient (F(ST) ) increases constantly. ZUSAMMENFASSUNG: Untersuchungen der Populationsstruktur der japanischen braunen Rasse Die Populationsstruktur in der Kumamotopr?fektur wurde an Hand einer Pedigreeanalyse untersucht. Zweihundert Kalbinnen wurden in den Jahren 1960, 1970, 1980 und 1990 zuf?llig ausgew?hlt und populationsgenetische Parameter F-Werte, Index der Unter-teilung und genetisch wirksame Zahl von Stieren gesch?tzt. Die wirksame Zahl von Vatertieren hat abgenommen, wobei das am st?rksten zwischen 1970 und 1980 vor sich gegangen ist. Der durchschnittliche Inzuchtkoeffizient (F(IT) ) zeigte Zunahme von 0, 64% im Jahr 1960 auf 5, 43% im Jahr 1990. F(ST) nahm parallel mit F(IT) zu, w?hrend F(IS) nieder geblieben ist. Von 1960 bis 1980 zeigte der Diversit?tsindex eine abnehmende Tendenz, hat aber sp?ter etwas zugenommen, wobei der Index im Jahr 1990 1, 1 erreicht hat. Die Populationsstruktur des japanischen Braunviehs ist derzeit keinen alarmierenden Status, aber F(ST) steigt kontinuierlich an.     

水牛品种改良的成果与发展思路

广西壮族自治区是全国开展水牛品种改良工作最早的省区之一。广西家畜人工授精站（现为广西壮族自治区畜禽品种改良站）于1954年成立，1958年起就开展了水牛的品种改良工作。50多年来，经过几代科研人员的不断研究和试验，由液态精液人工授精向冷冻精液人工授精技术转变的纵深发展，在关键核心技术上获得了重大突破，使科研与实际生产密切结合的水牛品种改良工作取得了举世瞩目的成就。     

T-cell-derived malignant lymphoma in the boxer breed

The boxer breed of dog is at high risk for a variety of neoplasms including lymphoma. In this observational study, tissue sections from boxer dogs with lymphoma were immunostained for T and B lymphocyte distinction, and the results compared with similar studies carried out on lymphoma tissues from temporally selected cohorts of golden retriever and rottweiler dogs. The frequency of T‐cell lymphomas was significantly (P < 0.001 for all comparisons) higher in the boxers than in the rottweilers or golden retrievers. We are unaware of other reports linking immunotype of canine lymphoma with breed; whether other brachycephalic breeds of dogs have a similar preponderance of T‐cell lymphoma awaits further study.     

高繁殖力绵羊品种简介

作者介绍了中外一些高繁殖力的绵羊品种的起源、繁殖性状、体型外貌等重要特征，旨在正确认识和了解国内外的高繁殖力绵羊品种，为引种和培育做参考，以促进我国养羊业的发展。     

《詹森育种原理》助我培育自己的品种——培育从一羽雄鸽开始

2008年《科学养鸽》第4期上刊登了笔者“《詹森育种原理》助我培育自己的品系”一文，原文标题本是“《詹森育种原理》助我培育自己的品味”，但编辑部考虑到“品系”一词比“品种”优雅，     

种鹌鹑的选种技术

近年来,鹌鹑养殖业正在不断扩大,但鹌鹑品种质量却有不同程度退化,我国目前大多种鹌鹑场对种鹌鹑的选种、选育工作并未引起重视,甚至一些所谓的种鹌鹑场将商品鹌鹑所产的的蛋当做种鹌鹑蛋来孵化,使鹌鹑的产蛋率和存活率大幅度下降,降低了养殖者的经济效益。本文主要从种鹌鹑的选种标准、时间、外貌选择、表型选择、蛋选、苗选、生产力鉴定、系谱鉴定、后裔鉴定、综合鉴定等方面进行阐述,以期使种鹌鹑场管理人员能在生产中重视鹌鹑的选种工作。     

关于荷兰牧羊犬品种的探究

公安部沈阳警犬基地于2002年8月引进荷兰牧羊犬5头,经过几年时间的饲养管理,以及查阅国内外有关荷兰牧羊犬的资料,对荷兰牧羊犬的起源、适应性、繁育、训练等方面有了一定的认识,现简要介绍如下,以助于大家对该犬种的了解。     

兰坪绒毛鸡品种特征及保护利用

兰坪绒毛鸡因全身羽毛呈丝状而得名,原产地为云南省兰坪白族普米族自治县（以下简称兰坪县）,中心产区为云南省兰坪县河西乡。2009年9月,国家畜禽遗传委员会家禽专业组对该畜禽遗传资源进行了现场鉴定,专家组对该遗传资源的品种特征、保护和开发利用进行了充分的肯定,     

Predicting breed composition using breed frequencies of 50,000 markers from the US Meat Animal Research Center 2,000 Bull Project

Knowledge of breed composition can be useful in multiple aspects of cattle production, and can be critical for analyzing the results of whole genome-wide association studies currently being conducted around the world. We examine the feasibility and accuracy of using genotype data from the most prevalent bovine genome-wide association studies platform, the Illumina BovineSNP50 array (Illumina Inc., San Diego, CA), to estimate breed composition for individual breeds of cattle. First, allele frequencies (of Illumina-defined allele B) of SNP on the array for each of 16 beef cattle breeds were defined by genotyping a large set of more than 2,000 bulls selected in cooperation with the respective breed associations to be representative of their breed. With these breed-specific allele frequencies, the breed compositions of approximately 2,000 two-, three-, and four-way cross (of 8 breeds) cattle produced at the US Meat Animal Research Center were predicted by using a simple multiple regression technique or Mendel (http://www.genetics.ucla.edu/software/mendel) and their genotypes from the Illumina BovineSNP50 array, and were then compared with pedigree-based estimates of breed composition. The accuracy of marker-based breed composition estimates was 89% when using either estimation method for all breeds except Angus and Red Angus (averaged 79%), based on comparing estimates with pedigree-based average breed composition. Accuracy increased to approximately 88% when these 2 breeds were combined into an aggregate Angus group. Additionally, we used a subset of these markers, approximately 3,000 that populate the Illumina Bovine3K (Illumina Inc.), to see whether breed composition could be estimated with similar accuracy when using this reduced panel of SNP makers. When breed composition was estimated using only SNP in common with the Bovine 3K array, accuracy was slightly reduced to 83%. These results suggest that SNP data from these arrays could be used to estimate breed composition in most US beef cattle in situations where pedigree is not known (e.g., multiple-sire natural service matings, non-source-verified animals in feedlots or at slaughter). This approach can aid analyses that depend on knowledge of breed composition, including identification and adjustment of breed-based population stratification, when performing genome-wide association studies on populations with incomplete pedigrees. In addition, SNP-based breed composition estimates may facilitate fitting cow germplasm to the environment, managing cattle in the feedlot, and tracing disease cases back to the geographic region or farm of origin.     

浅谈养好仔猪的技术要点

早喂初乳。初乳是母猪分娩后5～7天内分泌的淡黄色乳汁，和正常乳的化学成分不同，对初生仔猪有特别的生理作用。因为初乳中蛋白质含量最高，维生素丰富，并含有大量的免疫球蛋白，又有镁盐，有轻泻作用。可促使胎粪排出，而且初乳酸度较高，有利于消化道蠕动。初乳的各种营养物质，在小肠内几乎全部被吸收，有利于仔猪增长体力和产热，使仔猪从母乳中摄取免疫抗体不可取代的营养物质。因此，在仔猪出生后半小时内尽早吃到初乳，以增加免疫抗体，恢复体温，补给水分。     

影响种狐繁殖性能的营养因素

综述蛋白质、能量、维生素和微量元素等营养因素对种狐繁殖性能的影响，指出现存营养问题，旨在从营养学角度为提高种狐繁殖性能提供理论基础，增强毛皮生产者对种兽饲料营养的认识。