猪杂交配套系杂种优势利用分析

比较了杜长大杂交繁育体系与斯格配套系各纯系和杂交组合的生产性能,结果显示,斯格祖代猪与父母代猪产仔数、产活仔数、断奶仔数、断奶窝重的差异均达到极显著水平,父母代猪与祖代猪的初生窝重差异显著;斯格父母代猪的产仔数、产活仔数、断奶仔数和断奶窝重与长大母猪的差异均达到极显著水平,斯格父母代猪与长大母猪的初生窝重差异显著。繁殖性状的杂优率处于小到较高水平,斯格配套系父母代与商品代各时期平均日增重的差异均达到极显著水平,杜长大杂交体系父母代与商品代各时期平均日增重的差异均达到显著水平,斯格配套系父母代和商品代与杜长大杂交体系父母代和商品代日增重的差异均达到极显著水平,日增重具有中等杂优率。     

榆林猪繁殖性状研究

本文通过研究母猪乳头数、总产仔数、产活仔数、初生个体重、初生窝重、母猪泌乳力、断奶活仔数、断奶个体重和断奶窝重等繁殖性状的特点,发现榆林猪的繁殖性状主要表现在母猪有效乳头较多,7～8对乳头的母猪占61％以上。初生个体整齐度高,总产仔数、产活仔数、初生窝重、母猪泌乳力、断奶窝重等主要繁殖力性状个体间变异较大．有充分选择改良提升的空间。繁殖力性状的遗传力值较低,在0．11-0．20之间。     

皖南花猪不同头型母猪繁殖性能比较研究

皖南花猪按头型可分为狮子头型、马脸型和桩头型,为研究皖南花猪母猪不同头型母猪间的繁殖性能差异,研究通过整理安徽省皖南花猪保种场以往数据,现场记录等方法,统计皖南花猪不同头型经产母猪(370窝)的窝产仔数、窝产活仔数、初生窝重、35日龄窝断奶仔猪数和35日龄断奶窝重等繁殖性能指标,并进行比较分析。结果如下:皖南花猪马脸型母猪窝产仔数、窝产活仔数、仔猪初生窝重、35日龄断奶仔猪数、35日龄断奶窝重均显著高于狮子头型及桩头型母猪(P0.05);皖南花猪桩头型母猪在窝产仔数、窝产活仔数、仔猪初生窝重等繁殖性能上优于狮子头型母猪,但在35日龄断奶窝重这一指标中低于狮子头型母猪。研究表明皖南花猪马脸型母猪繁殖性能与狮子头型、桩头型母猪相比更为优异,为皖南花猪种质资源保护与开发利用提供了一定的参考依据。     

胎次对丹系大白猪繁殖性能的影响分析

对江苏省某国家生猪核心育种场丹系大白母猪各胎次的产仔数、产活仔数、断奶仔猪数及初生窝重、断奶窝重等繁殖性状进行了比较和相关性分析,旨在进一步了解丹系大白猪的繁殖性能,为后备母猪的选种选育提供参考。结果表明,丹系大白母猪第1、2胎产仔数较少,至第3胎达到最高为10.39头,后趋于稳定。不同胎次对产活仔数与断奶仔猪数的影响与产仔数的变化趋势基本一致。不同胎次的仔猪初生窝重基本持平,并以第3胎最高为14.81 kg。各胎次断奶窝重基本稳定。相关性分析表明,丹系大白母猪第3胎与第4胎产仔数、产活仔数、初生窝重呈显著正相关,第2胎与第5胎的产仔数、产活仔数、初生窝重间均呈显著负相关。第4胎与第5胎断奶仔猪数有显著负相关。第4胎和第5胎的断奶窝重有显著正相关。第3胎繁殖性能相对稳定,可以反映母猪繁殖性能,因此丹系大白母猪第3胎次的繁殖性能可作为选育后备母猪的重要依据。     

深县母猪乳头数对其繁殖性能的影响研究

为研究深县猪母猪乳头数与繁殖性能之间的关系,收集河北正农牧业有限公司2013年1月-2016年3月的深县猪的母猪正常分娩记录,随机选取83头深县母猪。结果表明:母猪乳头数达到18个时其窝产仔数和窝产活仔数达到最高,且显著高于乳头数为15个的母猪;乳头数与其每窝产仔数和窝产活仔数呈现正相关;母猪乳头数为16个和18个时极显著高于母猪乳头数为15个和17个的仔猪初生个体重(P0.01),且显著高其断奶个体重(P0.05);母猪乳头数为16个其仔猪初生窝重和断奶窝重极显著高于母猪乳头数为15个的母猪(P0.01);即母猪乳头的对称性对仔猪的初生个体重、初生窝重、断奶个体重和断奶窝重有一定的影响。说明适当增加母猪的乳头数有可能使母猪的繁殖性状得到相应的提高。。     

大约克母猪的几个主要繁殖性状表型相关分析

有关大约克母猪主要繁殖性状间的表型相关系数报道甚少，本文详细报导了33头大约克母猪的产仔数、产活仔数、初生窝重、泌乳力、断阴头数和断奶窝重及育成率等7项指标。经相关分析。产仔数与产活仔数，活仔数与初生窝重，继奶头数与继奶窝重属强正相关；产仔数与断奶头数，初生窝重与继奶窝重，泌乳力与断奶窝重属于等正相关；活仔数与泌乳力属弱正相关。     

胎次和配种季节对长白、大白母猪繁殖性能的影响

为了分析不同胎次、配种季节对母猪繁殖性能的影响,笔者对江西省赣州市某猪场2015年长白母猪、大白母猪的繁殖记录进行统计分析,并按胎次及配种季节进行分组,分析其在不同胎次、配种季节条件下的繁殖性能差异。结果表明:长白母猪和大白母猪3~5胎繁殖性能较好,第1胎的初生均重、断奶均重最低;长白母猪第3胎窝产活仔数最高,显著高于1,2,6,7,8胎(P0.05);大白母猪第4胎窝产活仔数最高,显著高于第1,2胎(P0.05);长白母猪夏季配种窝产仔数、窝产活仔数最高,初生均重、断奶均重春季配种最高;大白母猪不同季节配种窝产仔数差异不显著(P0.05),夏季、秋季配种产活仔数显著高于冬季(P0.05)。说明不同胎次、配种季节对长白、大白母猪繁殖性能有较大影响。     

妊娠期背膘厚对母猪产程及繁殖性能的影响

为优化母猪繁殖效率,探究妊娠期不同背膘厚对母猪繁殖性能和分娩产程的影响,本研究以广西某公司2 969头大白母猪和1 787头长白母猪为试验群体,收集2017年1月至2017年10月妊娠期3个阶段(妊娠30、80和107 d)背膘厚与分娩接产记录数据,分析背膘厚与分娩产程、总产仔数、产活仔数和初生窝重等性状的关系。研究结果表明,大白母猪分娩产程时间显著短于长白母猪(P<0.05),大白母猪总产仔数、产活仔数和初生窝重显著优于长白母猪(P<0.05)。在妊娠30 d时,背膘厚在18～20 mm组的大白母猪总产仔数和产活仔数最高,且初生窝重最大;背膘厚在18～20 mm组的长白母猪总产仔数和产活仔数最高。在妊娠80 d时,背膘厚≥20 mm组的大白母猪总产仔数和产活仔数最高,且初生窝重最大、产程最短;背膘厚在16～18 mm组的长白母猪总产仔数和产活仔数最高,且初生窝重较高、母猪产程较短。在妊娠107 d时,背膘厚在14～16 mm组的大白母猪总产仔数和产活仔数最高,且初生窝重最大,但母猪产程与其他组差异不显著(P>0.05);背膘厚≥20 mm组的长白母猪总产仔数和产活仔数最高,且初生窝重较大。妊娠期背膘厚减少1～2 mm的大白母猪,其总产仔数和产活仔数最高,初生窝重较小,产程较长。而背膘厚减少>2 mm的长白母猪,其总产仔数和产活仔数最高,初生窝重较大,产程较短。上述试验结果说明,在母猪妊娠期间,合适的背膘厚可有效提高母猪繁殖性能和母猪分娩期间的福利水平。养殖场可以根据营养配方和猪群品种建立背膘数据库,通过精准饲喂将母猪背膘厚调整至最佳范围,同时合理控制妊娠期背膘变化。     

杜洛克猪繁殖性状遗传参数估计及非遗传因素影响分析

为了对杜洛克猪繁殖性状进行遗传参数估计，并分析非遗传因素分娩季节及胎次对繁殖性状的影响，试验整理了陕西省某核心育种场2009—2020年杜洛克母猪繁殖性状数据，利用DMU软件估计各繁殖性状的遗传参数，结合R软件中aov函数对非遗传因素季节和胎次进行方差分析，研究遗传参数和非遗传因素对繁殖性状的影响。结果表明：杜洛克猪除妊娠周期为中等遗传力性状外，其余繁殖性状遗传力均在0.01～0.05之间，且总产仔数与产活仔数、健仔数、弱仔数、初生窝重之间为遗传正相关，妊娠周期与总产仔数、产活仔数、健仔数、死仔数、弱仔数、初生窝重之间呈遗传负相关。分娩胎次对杜洛克猪的总产仔数、产活仔数、健仔数、初生窝重、妊娠周期的影响达到极显著水平(P<0.01);而季节仅对死胎数、死仔数、妊娠周期3个性状具有极显著影响(P<0.01)。冬季损失的仔猪数最少，死仔数和死胎数显著低于春季、夏季、秋季(P<0.05),春季总产仔数、产活仔数、健仔数和初生窝重显著高于夏季、秋季、冬季(P<0.05),冬季妊娠周期显著长于春季、夏季、秋季(P<0.05)。分娩胎次为2胎次时的死胎数、死仔数、弱仔...     

大型约克母猪主要繁殖性状表型相关分析

以３３窝仔猪为试样,对３３头约克母猪的繁殖性状进行了表型相关分析,结果表明,产仔数与产活仔数、产活仔数与初生窝重呈强正相关;初生窝重与断奶窝重呈中等正相关;活仔数与泌乳力及断奶窝重呈弱正相关。     

猪配套系生长性状基因效应与杂种优势的分析

测定杜长大三元杂交体系和斯格配套系各杂交组合的生长性能,计算出生长性状的杂种优势率;选用5个与生长性状紧密连锁的微卫星标记对测定个体进行基因型检测,利用混合效应线性模型计算出生长性状各位点的基因效应。结果显示:斯格配套系父母代与商品代各时期的平均日增重的差异均达到极显著水平(P<0.01),杜长大杂交体系父母代与商品代各时期的平均日增重的差异均达到显著水平(P<0.05),斯格配套系父母代和商品代与杜长大杂交体系的父母代和商品代的差异达到极显著水平(P<0.01),前期的的杂优率处于较高水平,后期及全程的杂优率不高。基因效应分析显示早期日增重的基因效应既有加性效应又有显性效应,后期日增重和全程日增重的加性效应明显,因而加性效应是日增重杂种优势的主要遗传学基础。     

Heterosis and recombination effects in Hampshire and Landrace swine: I. Maternal traits.

Hampshire and Landrace sows and crossbreds of the two breeds were used to determine heterosis and recombination effects for milk production, milk composition, and litter traits at birth and d 21. Twelve mating types were represented in this study: two purebred, two F1, two F2, two F3, and four backcross. Information was gathered on a total of 358 litters over four farrowing seasons. Milk production was measured at d 10 and 20 of litter age according to the weigh-suckle-weigh procedure. Milk samples were collected at d 10 and 20 of litter age and evaluated for percentages of fat (PCFA), protein (PCPR), lactose (PCLA), and solids-not-fat (PCSN). The model used to evaluate litter traits at birth included main effects of mating type, parity, and farrowing season. The model used for milk production and milk composition traits included these main effects and number of pigs nursed as a covariate. Estimates of maternal genetic effects showed that Landrace females were superior to Hampshire females for number born (NB), number born alive (NBA), litter birth weight (LBW), adjusted 21-d litter weight (ALW), and milk production at d 10 of litter age (WT10). Hampshires were superior to Landrace for PCPR at d 10 of litter age and PCSN at d 10 and 20 of litter age. Heterosis effects were significant (P less than .05) for NBA (.97) and LBW (1.46 kg). Maternal heterosis effects were significant for LBW (3.94 kg; P less than .01). Epistatic recombination losses in the offspring were significant for LBW (6.80 kg; P less than .05). Differences in maternal performance of reciprocal F1 dams were generally not significant. Heterosis and recombination effects were not significant for milk production or milk composition.     

胎次对杜洛克、长白和大白母猪繁殖性能的影响

为了研究胎次对杜洛克、长白和大白母猪繁殖性能的影响,根据江苏省某国家级生猪核心育种场2009-2011年出生的繁殖母猪资料,分别选取128头杜洛克、681头长白和610头大白母猪共7280窝生产数据,统计分析不同胎次母猪的总产仔数、产活仔数、断奶仔猪数、初生窝重及校正21日龄窝重。此外,依据胎次将母猪分为3个繁殖阶段（1～2胎、3～6胎及7～8胎）来探究品种差异对母猪繁殖性能的影响。结果表明：胎次对母猪繁殖性能有显著影响（P<0.05）,母猪1～4胎的总产仔数、产活仔数、断奶仔猪数及初生窝重随胎次呈增加趋势,第4胎达到高峰,且显著高于其他胎次（P<0.05）;3～6胎繁殖性能较好,7胎之后出现迅速下降趋势;除在第4胎略有下降外,其他胎次的校正21日龄窝重随胎次递增。品种对母猪繁殖性能的影响显著（P<0.05）,长白和大白母猪的繁殖性能均极显著高于杜洛克母猪（P<0.01）;长白母猪的产活仔数和校正21日龄窝重显著高于大白母猪（P<0.05）,2个品种其他繁殖性能无显著差异（P＞0.05）。综上所述,杜洛克、长白和大白母猪的最佳繁殖胎次为3～6胎,长白猪的繁殖性能总体上优于大白猪,就本试验所在的育种场而言,长白猪可能更适合作为二元母猪生产中的母本。     

猪PRLR和FSHβ基因多态性检测及其与繁殖性状的关联分析

试验旨在研究催乳素受体（prolactin receptor,PRLR）和卵泡刺激素β（follicle-stimulating hormone β,FSHβ）基因的多态性及其与母猪繁殖性状的关联分析。采用PCR-RFLP方法对大白猪、杜洛克猪和长白猪3个猪种共487头母猪进行了PRLR和FSHβ基因多态性检验,并采用单因子方差分析、LSD法分析不同基因型与母猪总产仔数、产活仔数、断奶窝重和断奶窝仔数等繁殖性状的相关性。结果表明,PRLR基因在大白猪和长白猪中B等位基因均为优势基因,基因频率分别为0.717和0.548,大白猪BB基因型总产仔数显著高于AA基因型（P<0.05）,长白猪BB基因型断奶窝重显著高于AB基因型（P<0.05）;FSHβ基因在大白猪、杜洛克猪和长白猪3个猪种中B等位基因均为优势基因,基因频率分别为0.804、0.760和0.789,长白猪BB基因型总产仔数和产活仔数均显著高于AB基因型（P<0.05）,呈现BB>AA>AB趋势。因此,PRLR和FSHβ基因对荣昌猪场母猪繁殖性能有一定影响,可作为母猪繁殖性能分子选育的候选参考基因。     

Correlated responses in reproductive and carcass traits to selection for 70-day weight in Landrace swine.

Correlated responses in reproductive and carcass traits were studied in 181 litters and 218 pigs from a line of Landrace pigs selected six generations for increased weight at 70 d of age and a contemporaneous, randomly selected control line. The reproductive and maternal traits studied included litter sizes born, born alive, and alive at 21 d and litter weight at birth and at 21 d. Carcass traits studied were carcass length, longissimus muscle area, average backfat thickness, 10th-rib backfat thickness, specific gravity, weights of closely trimmed ham, loin, and shoulder, belly weight, subjective scoring of the longissimus muscle for color and marbling, estimated percentage of muscle, and lean gain per day. Total weighted cumulative selection differential for 70-d weight was 30.2 kg. The realized heritability for 70-d weight was .13 +/- .06, and the change in 70-d weight was .65 +/- .29 kg per generation. The regression coefficient of litter size at 21 d on generation was .24 +/- .10 (P less than .10) pigs per generation. None of the other regression coefficients for the reproductive traits differed from zero. Carcass length, specific gravity, and ham weight decreased (P less than .10) -.075 +/- .036 cm, -.00054 +/- .00027, and -.102 +/- .048 kg, respectively, per generation. Color score and lean gain per day increased .046 +/- .021 points and .0032 +/- .0013 kg/d, respectively, each generation in response to the selection.(ABSTRACT TRUNCATED AT 250 WORDS)     

4个主效基因与英系长白猪繁殖性能的相关性分析

为寻找有效的分子标记用于英系长白猪辅助育种进而提高其繁殖性能,在英系长白猪群（169头）中采用PCR-RFLP技术,进行雌激素受体（estrogen receptor,ESR）、视黄醛结合蛋白（retinol binding protein 4,RBP4）、瘦素（leptin,LEP）和促卵泡素亚基β（follicle-stimulating hormone β,FSHβ） 4种与繁殖性状相关基因的基因型频率检测,利用SPSS 19.0统计软件,采用最小二乘法将各基因不同基因型与总产仔数、产活仔数、断奶窝重、断奶头数进行了相关分析。结果显示,ESR、RBP4、LEP基因均以A为优势等位基因,FSHβ基因以B为优势等位基因,其中LEP、FSHβ基因多态位点符合Hardy-Weinberg平衡定律（P>0.05）,而ESR、RBP4基因多态位点处于Hardy-Weinberg不平衡状态（P<0.01）;LEP基因在长白猪母猪中表现为BB基因型为有利基因型,其总产仔数、产活仔数、断奶头数分别比AB基因型高1.3219、1.6855、1.1710头（P<0.05）;FSHβ基因中AA基因型为不利基因型,BB基因型断奶窝重比AA基因型高5.1129 kg（P<0.05）;ESR、RBP4基因对长白母猪繁殖性能均无显著影响（P>0.05）,而LEP、FSHβ基因可能作为有价值的候选基因应用于英系长白猪的分子标记辅助选择。     

The Association Analysis Between 4 Major Genes and Reproductive Traits in British Landrace Pigs

The purpose of this study was to identify candidate genes associated with reproduction traits and explore the available molecular marker in British Landrace pig breed. The PCR-RFLP technique was applied to analyze the distribution of estrogen receptor (ESR), retinol binding protein 4 (RBP4), leptin (LEP) and follicle-stimulating hormone β (FSHβ) genes in British Landrace pigs. The genetic effects of ESR, RBP4, LEP and FSHβ on the reproductive traits included total number born, number born alive, weaning weight of litter, weaning piglet, which were analyzed by using least square method of SPSS 19.0 software. This results demonstrated that A was dominant allele in ESR, RBP4, LEP genes, and B was dominant allele in FSHβ gene. The result of χ² test showed that the polymorphic sites of LEP, FSHβ genes were fit with Hardy-Weinberg equilibrium (P>0.05), while this site of ESR and RBP4 were not fit with Hardy-Weinberg equilibrium (P<0.01). In addition, the statistical analysis indicated that the total number born, number born alive and number of alive weaning litter with BB genotype of LEP were higher than AA genotype, which were significantly increased by 1.3219, 1.6855 and 1.1710 (P<0.05), respectively;The FSHβ loci had a remarkable effect on reproductive performance, the average weaning weight with BB genotype was significantly higher than AA genotype, which was significantly increased by 5.1129 kg (P<0.05). The ESR and RBP4 loci had no significant effect on reproductive traits (P>0.05), while the LEP and FSHβ genes were valuable candidates for possible marker-assisted selection in British Landrace pigs population.     

OVULATION RATE AT FIRST MATING AND REPRODUCTIVE PERFORMANCE OF GILTS

SUMMARY Laparoscopy was used to estimate ovulation rate at first mating in 460 Large White/Landrace gilts. For 385 gilts which farrowed litter size was recorded and the relationships between age and mating, maternal litter size, ovulation rate and reproductive performance were examined. The mean ovulation rate of the gilts which farrowed was 10.9 ± 0.14 corpora lutea and the mean first litter size was 8.0 ± 0.12 piglets born with 7.5 ≥.± 0.13 born alive. Ovulation rate was related to first litter size (r = 0.29, P < 0.001) but embryo loss was the major factor determining litter size, accounting for about 58% of the variation. None of the variable examined at the time of mating was sufficiently correlated with litter size to be useful as selection criteria for improving reproductive performance.     

长大、PIC、混血母猪繁殖性状研究

对红河州某猪场长大母猪311窝、PIC母猪138窝及当地农村饲养混血母猪753窝的繁殖性状进行测定,探讨品种、胎次和分娩季节对母猪繁殖性状的影响。结果表明,品种因素对母猪产仔性能有显著影响,长大母猪和混血母猪的总产仔数、产活仔数、初生窝重、28 d校正断奶窝重均极显著高于PIC母猪（P〈0.01）,长大母猪和混血母猪间除初生窝重、初生个体重和28 d校正断奶成活率有极显著差异（P〈0.01）外,其它指标差异均不显著（P〉0.05）。胎次因素对母猪产仔性能产生显著影响,经产母猪显著高于初产母猪（P〈0.05）,长大、PIC母猪2~8胎、混血母猪3胎以上产仔性能较好,其中长大、PIC母猪以第4胎最佳。分娩季节对PIC、混血母猪的繁殖性状无显著影响（P〉0.05）,而对长大母猪的产活仔数有显著影响（P〈0.05）。     

苏太猪SLA-DQA基因SNP检测及其对部分经济性状的遗传效应分析

实验对苏太猪SLA-DQA基因的第4外显子进行多态性分析,并初步探讨DQA基因作为影响苏太猪经济性状候选基因的可能性。PCR-SSCP分析共检测到CC、CD和DD 3种基因型;在第4外显子检测到G5233A突变,导致了氨基酸Thr到Ala的改变。结果表明:苏太猪3种基因型个体的初生重、35日龄断奶体重、4月龄体重、6月龄体重以及60 kg体尺和背膘厚等生长发育指标差异不显著(P0.05);DD基因型第3胎次总产仔数、产活仔数、初生窝重均高于CC和CD基因型的个体,尤其是断奶仔猪数和断奶窝重显著高于CC和CD基因型的个体(P0.05),但CC和CD基因型个体间繁殖性能差异不显著(P0.05)。