Influence of Postpartum Cloprostenol Treatment in Sows on Subsequent Reproductive Performance under Field Conditions

During the previous decade several studies focused on postpartum treatment with prostaglandin for improvement of reproductive performance in sows. The aim of the study was to investigate the effect of administration of a prostaglandin F_{2 α} (PGF_{2 α} ) analogue in sows within 24–48 h after farrowing on sow and litter performance. In five commercial farms, the sows were randomly assigned to either treatment A (2 ml cloprostenol, Planate^IM) or treatment B (2 ml physiological saline solution, i.m.). Fifteen per cent of all sows were at random selected for progesterone analysis. Litter performance was assessed by measuring pre-weaning mortality and average daily weight gain (ADG). Sow performance was assessed by measuring weaning-to-oestrus interval (WOI), the percentage of sows returning to oestrus and litter size during subsequent farrowing. Administration of a PGF_{2 α} analogue within 24–48 h postpartum had no effect on the rate of progesterone decline measured over 24 h compared with that of the controls. Litter performance and WOI were not affected by treatment. The subsequent litter size in sows of parity seven and more showed a significant difference of 1.98 piglets (p < 0.01) between both groups, to the benefit of the cloprostenol group. In conclusion, administration of a synthetic PGF_{2 α} analogue, cloprostenol, within 24–48 h after farrowing improved litter size at next farrowing in older (≥7 parity) sows.     

定时输精对经产母猪繁殖性能及生殖激素的影响

试验旨在建立高效的经产母猪定时输精（timed artificial insemination,TAI）技术,研究了定时输精对经产母猪繁殖性能、断奶-分娩间隔、不同胎次母猪产仔性能及断奶后7 d内血清生殖激素水平的影响。选取309头2~8胎次二元（长×大）经产母猪,随机分为对照组和试验组,对照组母猪进行常规人工授精（artificial insemination,AI）,试验组母猪进行断奶后24 h注射PMSG 1 000 IU,间隔72 h注射GnRH 100 μg,在注射GnRH后24和40 h各输精1次的定时输精技术。通过统计两组母猪的断奶1周内发情率、受胎率、分娩率、窝均产仔数等,判断定时输精对经产母猪繁殖性能的影响;通过对断奶时间和分娩时间的统计,检测定时输精对经产母猪断奶-分娩间隔的影响;用放射免疫（RIA）方法检测2~4胎次母猪断奶1周内血清E₂、LH、FSH和P₄的含量,研究定时输精对母猪生殖激素的影响。结果显示,试验组母猪发情率显著高于对照组（P<0.05）,但两组间受胎率、分娩率差异不显著（P>0.05）,窝均产仔数、窝均合格仔数和繁殖效率有增加的趋势,但差异不显著（P>0.05）;定时输精显著缩短了母猪的断奶-分娩间隔（P<0.05）。在胎次方面,3~4胎母猪使用定时输精的效果较好,其发情率、受胎率和分娩率均显著高于对照组（P<0.05）。在生殖激素方面,试验组E₂水平在注射PMSG后迅速上升,且在定时输精处理后66~96 h内持续高于对照组（P<0.05）,试验组P₄水平在断奶后至配种前显著低于对照组（P<0.05）,但配种后快速升高,并高于对照组;LH和FSH的含量在两组间无显著差异。综上,定时输精可有效提高经产母猪的断奶发情率,并减少其非生产天数,可显著提高3~4胎母猪的繁殖性能。     

影响母猪产仔数和初生重的因素分析

随着现代养猪业的发展,养猪规模越来越大,其繁殖效率也就越容易受到影响而下降,进而影响生产效益,然而提高生产效益的两个关健因素就是精液品质和母猪繁殖力。为了探讨精液品质对母猪繁殖力的影响,本试验统计了河南省驻马店诸美种猪场2006~2013年母猪配种、产仔记录,分析了猪精液质量(精子活率和精子密度)与母猪繁殖力(窝产仔数和初生窝重)的相关性。结果表明:(1)产仔性能最好的是长白猪,大白猪次之,杜洛克猪最差,三个品种的平均窝产仔数分别是10.52头、9.96头、9.05头;第3胎达到最大值,其产仔数分别为11.25头、10.23头、9.57头。(2)精子活率与杜洛克、长白、大白种猪的窝产总仔数、初生窝重呈极显著相关(P0.01)。(3)精子密度与杜洛克、大白种猪窝产总仔数和初生窝重呈极显著相关(P0.01),与长白种猪的没有显著相关(P0.05),表明影响母猪繁殖成绩的关键因素是精子活率。     

铬对母猪繁殖性能的影响及其作用机制

铬是动物机体所必需的微量元素之一。研究发现,铬能够通过调节胰岛素来改善糖类和脂类代谢、提高动物的免疫力和抗应激能力,进而对母猪的生长性能和繁殖性能产生影响。本文综述了铬对母猪繁殖性能的影响及其作用机制,为铬在母猪上的合理应用提供参考。     

脯氨酸对母猪繁殖性能影响的研究进展

脯氨酸为环状的α-亚氨基酸,同时也是哺乳动物的功能性氨基酸,在蛋白合成、机体新陈代谢、伤口愈合、抗氧化反应和免疫反应中发挥着重要作用。研究发现,添加适量的外源性脯氨酸,可以促进胎儿与仔猪的生长发育、预防胎儿宫内生长迟缓,同时对胚胎、乳腺及胎盘生长发育具有重要的意义。作者阐述了脯氨酸的结构特征、理化性质、合成和分解代谢,重点介绍了脯氨酸对母猪繁殖性能的影响及其潜在的机制,为进一步研究脯氨酸对母猪繁育的影响提供参考。     

Some Factors Influencing Pregnancy Rate and Subsequent Litter Size in Primiparous Sows

The pregnancy rate and the subsequent litter size were studied in 332 Swedish Yorkshire primiparous sows, fed according to a commercial Swedish feeding regime during lactation. The sows were weighed and backfat depth was recorded at the first farrowing, at weaning, and at mating. Oestrous detection was performed once daily after weaning, and the interval from weaning to first oestrus (IWO) was recorded. Blood samples for determination of plasma progesterone were drawn regularly after the first weaning. Statistical analyses were only performed on sows with an IWO of 3-8 days. Of these 206 sows were mated on their first (OE1 sows) and 87 sows on their second (87 OE2 sows) oestrus after weaning.The pregnancy rate was 85.4% for OE1 sows and 75.9% for OE2 sows (p=0.048). There was no significant difference in pregnancy rate between OE1 sows with an IWO of 3-5 days and OE1 sows with an interval of 6-8 days. OE2 sows with an IWO of 6-8 days, on the other hand, had a significantly lower pregnancy rate compared with OE2 sows with an interval of 3-5 days. The pregnancy rate in sows that lost more than 30 kg during the first lactation period did not differ from that of sows losing less than 30 kg. In sows with a first litter size of more than 9 piglets alive at birth, the pregnancy rate decreases significantly if mating is delayed until the second oestrus after weaning.OE2 sows had a significantly larger second litter size at birth than OE1 sows (+ 2.0). The litter size at six weeks did not, on the other hand, differ significantly (+ 0.4). There was a positive correlation between the IWO and 2nd litter size, although significant only for OE1 sows between the IWO and litter size alive at birth. In the OE1 group, sows losing 20 kg or less during lactation had significantly larger second litters at birth than the sows losing 21-30 kg, but not significantly larger than the sows losing more than 30 kg. One piglet more, at birth, in the first litter resulted in 0.25 piglet more in the second litter. For sows with a large first litter there was a low probability of also having a large second litter.     

环境温湿度对母猪繁殖性能的影响

浙江中白母猪繁殖成绩与地面温湿气象资料相结合进行统计分析的结果表明,母猪在60天哺乳期饲养制度下,产后发情并配种受孕平均需66.57天。其中离仔后配种占75.41％,就这部分母猪而言,离仔次旬平均日最高气温超过30℃或RH78％以上或THI值大于75,离猪后7天内的受孕率显著降低;配种时和配种后20天内受高温剌激,胎几发育数减少,平均气温25℃以上时的窝仔数(11.73头、11.83头)较20—25℃条件下少0.68头和0.37头;产前当旬处于高温的,产仔成活率较高;20日龄仔猪存活率以出生后次旬环境温度在20℃以上或THI值大于65时为高,而35—45日龄时的环境温湿度对20—60日龄仔猪存活率影响不明显。     

Research Progress on Effects of Proline on Reproductive Performance of Sows

Proline is a cyclic α-imino acids,meanwhile it also can be considered as a functional amino acid for mammals and plays an important role in protein synthesis,organism metabolism,wound healing,anti-oxidant and immune reactions. The studys have found that extra dietary supplementation of moderated proline has great significance in improving the growth and development of conceptus,piglets, embryo,mammary gland and placenta of sows,at the same time it also can prevent intrauterine growth restriction. The author reviewed structure characters and physicochemical properties,anabolism and catabolism of proline,and especially focused on its effects on the reproductive performance of pregnancy sows and potential regulation mechanism aiming to provide some help for the researchers in the field of sows.     

日粮添加鱼油对母猪繁殖性能的影响

每头母猪每年提供的健康的断奶活仔猪数决定了养猪生产的效益,母猪妊娠和泌乳期日粮中添加鱼油能够改变母体繁殖组织或者胚胎/胎儿组织中的脂肪酸组成,提高窝产仔猪数,促进哺乳期仔猪生长性能,提高母体和后代的健康状况.因此在妊娠和泌乳母猪日粮中添加1%～2%的鱼油能够提高母猪的繁殖性能.     

The Effect of Intravaginal Applied GnRH-agonist on the Time of Ovulation and Subsequent Reproductive Performance of Weaned Multiparous Sows

In order to prove the effect of 'fixed time insemination' and insemination at standing oestrus after post-weaning application of GnRH, in a Croatian large breeding unit, 502 sows were assigned to three groups and were artificially inseminated (AI) at their first post-weaning oestrus as many times as they stand, in 24-h intervals. The groups were treated as follows: group 1 (control, n = 160) were AI during their standing reflex; group 2 ['GnRH-fixed time insemination' (GnRH-FT-AI), n = 175] were AI, independent of detection of oestrus and following administration of GnRH-agonist at 96 h post-weaning; group 3 [GnRH insemination at standing oestrus (GnRH-OE-AI), n = 167] the animals were GnRH-agonist treated as group 2 and were AI at their standing reflex. Pre-trial daily average lactational feed intake, average daily feed intake from weaning to oestrus, oestrus within 6 days post-weaning (%), ovulation within 6 days post-weaning (%), weaning-to-oestrus interval (h), duration of oestrus (h), follicle size (mm), interval from oestrus to ovulation (h), subsequent day 24 pregnancy rate (%), farrowing rate (%) and total pigs born were evaluated. Pre-trial average daily lactational voluntary feed intake was 7.1 +/- 0.08 kg in group 1, 7.0 +/- 0.07 kg in group 2 and 7.1 +/- 0.17 kg in group 3 (p > 0.05). Average voluntary daily feed intake from weaning to oestrus was 5.1 +/- 0.3 kg in group 1, 5.2 +/- 0.5 kg in group 2 and 5.2 +/- 0.19 kg in group 3 (p > 0.05). Oestrus was detected within 6 days post-weaning in 134 (83.8%) in control, 164 (93.7%) in GnRH-FT-AI and 155 (92.8%) animals in GnRH-OE-AI groups (p = 0.05). Follicle size did not differ (p > 0.05) among the groups. In control 82.8%, in GnRH-FT-AI 91.5% and in GnRH-OE-AI 91.0% of the sows ovulated within 6 days post-weaning (p = 0.04), and had 80.6, 90.9 and 89.7% 24-day pregnancy rates (p = 0.16), respectively. In GnRH-FT-AI group 90.2%, in GnRH-OE-AI sows 89.7%, in control animals 79.9% farrowing rates were recorded (p = 0.17). Weaning to oestrus interval was 113.1 h in control, 114.1 h in GnRH-FT-AI and 112.6 h GnRH-OE-AI (p > 0.05). Duration of oestrus was significantly shorter in GnRH-FT-AI (44.9 h) and GnRH-OE-AI (48.1 h) animals, compared with the control (62.9 h) sows (p = 0.001). Similarly, the interval from oestrus to ovulation revealed significant (p = 0.004) differences between the groups (control 44.1 h, GnRH-OE-AI 34.1 h and GnRH-FT-AI 32.9 h). GnRH-FT-AI (12.5) and GnRH-OE-AI (12.6) sows had significantly higher (p = 0.01) number of total pigs born (n = 10.4) compared with control sows. GnRH-agonist-gel treatment to the sow shortens duration of oestrus, the interval from oestrus to ovulation, and may eliminate the need for oestrus detection in the hands of skilled personnel.     

日粮中添加天蚕素抗菌肽对母猪繁殖性能的影响

为探讨日粮中添加天蚕素抗菌肽对母猪生产性能的影响,试验选取32头二胎经产母猪,采用单因子完全随机设计,分为试验组和对照组,试验组从母猪分娩前30 d到产后21 d添加400 kg/mg天蚕素抗菌肽,对照组按猪场正常药物保健程序进行（母猪产前产后在饲料中添加阿莫西林400 kg/mg和支原净300 kg/mg）。结果表明,对照组的活仔率、健仔率均极显著低于试验组（P＜0.01）;试验组初生重、21 d体重、日增重和成活率均高于对照组,但差异不显著（P＞0.05）;试验组的腹泻率显著低于对照组（P＜0.05）。     

饲粮中添加发酵苜蓿对母猪繁殖性能和母猪、仔猪抗氧化能力的影响

本试验旨在研究饲粮中添加发酵苜蓿对母猪繁殖性能和母猪、仔猪抗氧化能力的影响。选用80头体况和预产期接近的“长×大”妊娠初产母猪,随机分为4组(对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组),分别饲喂添加0、5%、10%和15%发酵苜蓿的饲粮,每组5个重复,每个重复4头。试验从母猪妊娠开始到哺乳期结束。结果表明：1)与对照组相比,试验Ⅱ组的成活率、健仔数和健仔率显著升高(P<0.05),死胎数、弱仔数和产程显著降低(P<0.05);各试验组的宫内发育迟缓(IUGR)发生率显著降低(P<0.05)。2)与对照组相比,试验Ⅰ组母猪哺乳期平均日采食量显著升高(P<0.05),试验Ⅱ组有升高趋势(P=0.064);试验Ⅱ组、试验Ⅲ组妊娠30 d、妊娠60 d和产前背膘厚显著降低(P<0.05)。3)与对照组相比,试验Ⅱ组、试验Ⅲ组的初生窝重、第7天窝重及个体重、第14天窝重及个体重和断奶个体重显著升高(P<0.05);试验Ⅱ组的断奶窝重、窝平均日增重和初生个体重显著升高(P<0.05)。4)与对照组相比,试验Ⅱ组的初生窝重均匀度显著提高(P<0.05);试...     

妊娠母猪膘情对繁殖性能的影响

为研究妊娠母猪膘情与繁殖性能的关系,试验随机选用32头妊娠母猪,用B超活体测定其产前3 d倒数3、4肋骨间、胸腰椎结合处、腰荐椎结合处偏离背中线5~8 cm处背膘厚,并与其窝产仔数、产活仔数、死胎数、、仔猪初生重、初生窝重、18日龄断奶重、断奶窝重及断奶后发情天数等指标进行比较。结果显示,背膘厚度较薄组各项繁殖指标普遍优于背膘厚组,说明保持适当膘情对妊娠母猪繁殖性能的提高具有促进作用。     

基础日粮添加蜂胶对母猪生产性能的影响

为了研究蜂胶对母猪生产性能的影响,选择16头配种时间、胎次基本一致的长大妊娠母猪为材料,随机分成对照组和试验组。对照组只饲喂基础日粮,试验组则在基础日粮中添加蜂胶。试验从母猪妊娠81d进产房开始,到仔猪21日龄断奶后7d结束。研究结果表明,与对照组相比,试验组仔猪断奶重平均提高0.62kg,差异极显著(P<0.01);成活率提高4.51%,差异显著(P<0.05);在哺乳和断奶前7d,试验组仔猪腹泻率分别比对照组低1.37%(P<0.05)、2.96%(P<0.01)。因此,蜂胶对提高母猪生产性能有较大促进作用。     

饲粮中添加苹果渣对妊娠母猪粪便及繁殖性能的影响

本试验旨在研究饲粮中添加苹果渣对妊娠母猪粪便和繁殖性能的影响。选用胎次、体况相近,健康状况良好的妊娠母猪(长白×大约克)80头,随机分为2组(对照组和试验组),每组40个重复,每个重复1头母猪。对照组和试验组母猪在妊娠第1~89天分别饲喂妊娠母猪饲粮A(不含苹果渣)和妊娠母猪饲粮B(含10%苹果渣),在妊娠第90天至分娩当天分别饲喂哺乳母猪饲粮A(不含苹果渣)和哺乳母猪饲粮B(含5%苹果渣)。试验自妊娠开始,试验期为1个妊娠周期。结果表明：1)饲粮中添加苹果渣后,母猪排便通畅,粪量增加,粪色深黑,粪形呈筒状,可堆积成形,这说明苹果渣的添加缓解了妊娠母猪便秘的发生;2)饲粮中添加苹果渣对产仔数、产活仔数、初生窝重、初生个体均重的影响不显著( P>0.05),但极显著降低了母猪的便秘发生率( P<0.01),试验组比对照组降低35%。由此可见,饲粮中添加苹果渣可极显著降低妊娠母猪的便秘发生率,但对其繁殖性能没有显著影响。     

维生素A对母猪繁殖性能的影响

在概述VA的来源、代谢及对母猪繁殖性能的作用机理的基础上,阐明了VA缺乏对繁殖母猪生产性能的影响.着重指出VA在提高繁殖母猪生产性能中起着积极作用,是不可缺少的营养素之一.     

深部输精对母猪繁殖性能的影响

 试验以78头经产大白母猪为试验材料,采用深部输精技术,以探明深部输精对母猪繁殖性能的影响。试验分三个处理组：第Ⅰ组采用常规输精方法,输精次数3次;第Ⅱ组采用深部输精方法,输精次数3次;第Ⅲ组采用深部输精方法,输精次数为2次。试验结果：常规输精组（第Ⅰ组）和深部输精组（第Ⅱ组）比较,窝均产仔数、窝均产活仔数和窝平均产健仔数分别为11.39头、11.84头、10.52头,和12.40头、11.07头、10.43头,窝均产仔数深度输精高于常规输精,经分析二者达到显著水平（P＜0.05）,而窝均产活仔数和窝均产健仔数差异不显著（P＞0.05）;健仔率比较,常规输精组为91.54%,深部输精组为84.84%,二者差异达到显著水平（P＜0.05）;深度输精三次（第Ⅱ组）和深度输精两次（第Ⅲ组）相比母猪繁殖性状指标间差异均不显著（P＞0.05）。试验结果表明：深部输精可以提高母猪的窝均产仔数,但不能提高窝均产活仔数和健仔数,同时深部输精降低健仔率。     

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。     

玉米赤霉烯酮对母猪繁殖性能和胎盘免疫相关基因表达量的影响

本试验旨在研究饲粮中添加玉米赤霉烯酮(ZEN)对母猪繁殖性能和胎盘免疫相关基因表达量的影响。选择胎次相近、体重200 kg、妊娠第30天的长×大二元杂交母猪40头,随机分为2组,每组20个重复,每个重复1头。对照组饲喂基础饲粮,试验组饲粮在基础饲粮中添加1.5 mg/kg的ZEN。试验期74 d。结果表明,与对照组相比:1)饲粮中添加ZEN显著提高了妊娠期母猪死胎数和弱仔猪数(P0.05),显著降低了母猪总产仔数(P0.05);2)饲粮中添加ZEN显著提高了妊娠期母猪血清孕酮含量(P0.05);3)饲粮中添加ZEN显著提高了妊娠期母猪胎盘中Toll样受体-2(TLR-2)和孕酮受体(PGR)基因表达量(P0.05)。由此可见,母猪妊娠期饲粮中添加1.5 mg/kg ZEN可显著降低母猪总产仔数,并显著提高死胎数和弱仔猪数。饲粮中低水平的ZEN对母猪繁殖性能仍产生不利影响。