为探究动物遗传育种技术的发展历程,本文依据目前动物遗传育种的发展主线,结合畜禽育种现状,从传统育种技术到现代生物技术发展趋势进行阐述,并对各类育种技术的优缺点进行了归纳和比较,以期对从事动物遗传育种的工作人员提供一些思路和借鉴.

为揭示八眉猪DRD1基因多态性对其繁殖性能及生长性能的影响,以青海八眉猪为研究对象,对DRD1基因多态性与生长性状、产仔数进行相关性分析;利用生物信息学工具分析猪及其他近缘物种DRD1蛋白结构的保守性,作为评估八眉猪DRD1基因功能的基础.结果表明:猪DRD1蛋白在一、二、三级结构上与人等哺乳动物存在大量相似性结构;在遗传进化上和牛关系较近.青海八眉猪DRD1外显子区域存在一个多态性位点,但存在2种突变类型:Type1(g.1159C＞T)和Type2(g.1159C＞G),其中Type1位点是主要突变类型,在整个检测群体中处于哈代-温伯格平衡状态,Type2型分布不平衡.Type1和Type2型突变有利于青海八眉猪产仔数提高,其中Type1型突变纯合型TT产仔数显著高于野生纯合CC和杂合CT型(P＜0.05)o Type1和Type2的多态性引起了体高、体长等生长性状变化,但未达到显著水平(P＞0.05).因此,青海八眉猪DRD1基因的此SNP位点可考虑作为其产仔性状相关分子标记的候选基因位点,为青海八眉猪的分子辅助选育工作提供基础.

通过对青海八眉猪原种、长×八、约×长×八以及对照杜×长×大等胴体性能分析,结果显示,八眉猪原种、长×八、约×长×八及杜×长×大等屠宰率和瘦肉率分别为65.35％和43.36％、66.51％和47.10％、67.34％和52.47％、70.30％和73.45％.眼肌面积也呈增长趋势,且八眉原种、长×八、约×长×八的瘦肉率显著低于杜×长×大瘦肉率(P<0.05),八眉原种、长×八、约×长×八的眼肌面积显著低于杜×长×大眼肌面积(P<0.05),八眉原种、长×八、约×长×八脂肪率分别极显著高于杜×长×大脂肪率(P<0.01),虽然杜×长×大肉骨比显著高于八眉猪原种、长×八及约×长×八(P<0.05),但背膘厚和平均背膘厚却低于其他三组,内脏指标各组间略有不同且相互间无显著差异,表明八眉猪与引进猪种杂交后呈现出较好的配合力,杂交优势明显,胴体性能得到了改善,为今后八眉猪选育、繁育和综合开发利用奠定基础.

抗生素在养猪产业中的预防和疫病的治疗、提高免疫力等方面发挥着重要的作用,导致抗生素在养殖过程中广泛应用,但由于其使用不规范导致耐药性的出现及畜产品药物残留,对养猪业及高产安全造成了很大的影响.当前,减抗养殖向无抗养殖的发展逐渐成为趋势,本文从抗生素滥用的危害、生猪无抗养殖的主要措施、生猪无抗养殖推广面临的问题三个方面进行讨论,分析无抗养殖在发展中取得的成果和存在的主要问题,为推广利用无抗养殖及畜牧养殖业效益与生态环境保护提供理论依据,从而开拓新的发展思路和途径.

日粮纤维作为饲料的重要组成成分,对猪只的生产性能和健康状况都有积极作用,日粮纤维对猪只采食量、饲料利用率及肠道健康的研究已引起国内外广泛关注.文章综述了日粮纤维对猪只生长性能、营养利用及肠道微生物的影响,为今后探究猪只对饲料中日粮纤维的利用提供参考.

The fermented feed has been identified as a potential alternative to antibiotics in feeds that markedly affects gut health and growth performance of pigs. Two recent studies performed in our laboratory investigated that the fermented corn-soybean meal (fermented feed, FF) improved the gut health of pigs. This study was conducted to determine the effect of a FF on the carcass, meat quality, muscle fatty acids profile, muscle amino acid and antioxidant ability of grower-finisher pigs. In this study, a total of 48 crossbred barrows (Duroc × Landrace × Large White) were randomly divided into 2 treatments with unfermented corn-soybean diet (Ctrl) and FF diet. Compared with control pigs fed a standard diet, the results showed that FF significantly increased the muscle colour of redness and significantly reduced muscle moisture loss rate. Furthermore, FF significantly increased the content of aromatic amino acids such as aspartic acid, glutamic acid and alanine. More importantly, FF increased monounsaturated fatty acid and polyunsaturated fatty acid content. Collectively, FF could be a promising feed strategy in improving meat quality and nutritional value in grower-finisher pig.

Fermented corn-soybean meal (fermented feed, FF) is commonly used in swine production, but the effects of FF on gut health remain unclear. In this study, serum immunity, mRNA abundances of antimicrobial peptides (AMPs) and Toll-like receptors (TLR1-9), bacterial abundance in the duodenum and colon, and colonic metabolic phenotypes were determined in crossbred barrows (Duroc × Landrace × Large White) fed FF or normal feed (unfermented feed, UF) (n = 6). When compared to the UF group, the results showed that serum levels of IgG and IgM were significantly increased in FF group pigs (P < 0.05). FF significantly decreased the abundances of Bacteroides and Verrucomicrobia in the duodenum and decreased the abundances of Bacteroides, Proteobacteria, and Verrucomicrobia in the colon while it significantly increased the abundances of Firmicutes and Actinobacteria (P < 0.05). Furthermore, a Spearman's correlation analysis showed that serum immunity and the expression of genes related to gut immunity were associated with bacterial strains at the family level. Moreover, differentially abundant colonic microbiota were associated with colonic metabolites. LC-MS data analyses identified a total of 1,351 metabolites that markedly differed between the UF and FF groups. C5-Branched dibasic acid metabolism was significantly upregulated whereas the purine metabolism was significantly downregulated (P < 0.05) in the colonic digesta of pigs in the FF meal group compared to the UF meal group. Collectively, these results indicated that FF meal could influence serum immunity and the expression of genes related to gut immunity, correlating with the gut microbiota and bacterial metabolites in grower-finisher pigs. This study may provide an alternative strategy for improving the intestinal health of grower-finisher pigs.

为研究八眉母猪背膘厚度与繁殖性能的关系,对母猪妊娠3个阶段(30,60,90 d)的背膘厚及母猪的产仔性能进行Pearson关联性分析;并对不同妊娠期和不同背膘厚度下的母猪总产仔数、产活仔数、断奶仔猪数、平均断奶窝重情况进行统计比较.结果 表明:妊娠30 d,背膘厚与产活仔数和断奶仔猪数显著正相关(P＜0.05),妊娠60和90 d背膘厚度与繁殖性能相关性不大.妊娠30 d,高背膘厚组(13.9～14.8 mm),总产仔数、断奶仔猪数及产活仔数显著高于低背膘厚组(11.9～12.8 mm)(P＜0.05);妊娠60 d,低背膘厚组的总产仔数显著高于中等及高背膘厚组(P＜0.05),平均断奶窝重显著高于高背膘厚组(P＜0.05);妊娠90 d,中等背膘厚组(12.9～13.8 mm)断奶仔猪数显著低于低背膘厚组(P＜0.05).综上所述,八眉猪妊娠前期30 d适宜背膘厚度为13.9 ～ 14.8 mm;60和90 d的适宜背膘厚度分别为11.9～12.8 mm和12.9～13.8 mm,能够获得较好的产仔性能,这为八眉猪妊娠期饲养管理和营养调控提供理论依据.

为探讨不同性别对关中黑猪生长性能、血液指标及宰前应激的影响,选取10头体重(6.34±0.14)kg的关中黑猪,公母各半,进行分栏饲养,公猪在7日龄去势.分阶段对关中黑猪的体尺进行测量,并在屠宰时采集其血液,对其血液常规指标和应激指标进行检测.结果显示,关中黑猪去势公猪体重自5月龄起显著高于母猪(P＜0.05),体长在2月龄和8月龄显著高于母猪(P＜0.05),体高和腿臀围在2月龄和6月龄显著高于母猪(P＜0.05),胸围自6月龄起显著高于母猪(P＜0.05).关中黑猪的血液生化指标在性别间无显著影响(P＞0.05).关中黑猪去势公猪血液中肌酸激酶含量显著低于母猪(P＜0.05),并且检测到血液中乳酸含量也有同样趋势.综合考虑得出,关中黑猪去势公猪的生长性能及抗应激性能优于母猪.

Fermentation has attracted increasing attention in pig industry, because of low costs and numerous benefits on pig growth and health as well as environmental improvement, although the mechanisms remain largely unknown. In the present study, fermented corn-soybean meal significantly improved average daily gain and gain:food ratio (P < 0.05). Fermented feed (FF) significantly increased insulin-like growth factor 1 (IGF1) transcription in liver (P < 0.05). Meanwhile, fermented meal significantly enhanced the binding of CCAAT/enhancer-binding protein beta (C/EBPβ) to IGF1 promoter and C/EBPβ expression in liver (both P < 0.05). FF tended to increase IGF1 proteins in liver and serum too (both 0.05 < P < 0.10). Meanwhile, FF slightly but significantly increased hepatic and circulating triglyceride and total cholesterol levels, as well as serum ratio of high-density to low-density cholesterol (all P < 0.05). Our data indicated that FF could significantly augment the binding of C/EBPβ to IGF1 promoter and promote hepatic IGF1 expression and production, thus boost pig growth.

为研究日粮中添加枸杞对公猪精液品质的影响,试验选取12头身体状况良好的成年杜洛克公猪,随机分成4组,每组3头重复.对照组饲喂基础日粮,试验组分别在基础日粮中添加1.5％,3％,4.5％枸杞果粉,试验期60d.结果表明:试验组进入采精栏开始爬台的时间均显著低于对照组;1.5％枸杞组和4.5％枸杞组公猪精液量显著升高(P＜0.05),而3.0％枸杞组精液量有增加的趋势,但差异不显著(P＞0.05);各试验组公猪精液精子活力和精液密度显著高于对照组(P＜0.05);4.5％枸杞组的精子畸形率显著低于对照组(P＜0.05),而其他两组无显著变化(P＞0.05);各试验组公猪精液超氧化物歧化酶含量均显著提高(P＜0.05);3.0％枸杞组和4.5％枸杞组公猪精液丙二醛含量显著降低(P＜0.05),而1.5％枸杞组无显著变化(P＞0.05).由此说明,日粮中添加4.5％枸杞能够改善公猪精液品质.

我国是世界第一养猪大国,猪肉产量占世界总产量的50％左右.猪肉消费在我国居民的肉类消费中占据绝对的主导地位,在畜牧业生产和改善人民生活水平中具有举足轻重的作用.随着我国居民生活水平的不断提高,在注重肉类消费数量的同时更加关注质量,肉品质量与每个人的健康息息相关.本文就猪肉品质的评价指标,肌肉感官、肌肉营养成分、肌纤维特性等影响猪肉品质评价指标的因素等进行综述,以期为进一步改善和提高猪肉质量提供参考,从而不断促进生猪产业的健康发展,为提高人们生活水平作出更大贡献.

抗生素类药物为畜牧业的发展做出了巨大贡献,但长期使用抗生素会使畜禽产生耐药性和抗药性,对畜禽的免疫功能造成影响,甚至在畜禽产品中存在药物残留,带来严重的食品安全问题,从而引起消费者的忧虑.因此,开发抗生素的替代品已经成为新形势下的必然要求.中草药添加剂有无污染、无残留并且不产生抗药性等优点,以其独特的作用效果和多样的应用功能得到人们的青睐.中草药添加剂已广泛应用于养殖业,目前主要用于提高畜禽的免疫力、促进畜禽生长发育、提高畜禽繁殖性能以及改善畜禽产品质量.中草药添加剂的应用保障了畜禽产品安全,为健康养殖带来新的希望.