绥阳母猪与苏本杂母猪繁殖性能体尺及体重的比较

绥阳县自1960年引进苏白公猪进行经济杂交以来,当地群众盲目选用苏本杂交母猪运用于生产,导致苏本杂交母猪逐渐增加,据统计,到1990年为止,苏本杂母猪的数量已达母猪总数的50%,而且还在继续上升。照此下去,绥阳本地母猪有可被能苏本杂母猪取而代之。为了弄清杂交母猪的生产性能情     

繁殖母猪的体重变化对连产性能和繁殖成绩的影响

繁殖母猪的体重变化对连产性能和繁殖成绩的影响堀北哲也渡边一夫山本辉次等在我们所辖区内的Ａ养猪场，根据其日常繁殖管理记录，对繁殖母猪３５２头（计２７２３产次）的体重（分娩前体重、断奶时体重）、繁殖成绩、淘汰产次等之间的关系进行了分析和总结。结果发现，前...     

提高母猪产奶量和减少体重损失的饲喂策略

很多养猪场一味地追求增加母猪窝产仔猪数,这使得很多母猪出现负能量平衡的体质。一旦形成负能量平衡,会使得母猪的体质急剧下降,从而影响繁殖能力。最明显的表现就是母猪奶水不够,影响乳猪发育。因此,对妊娠期和泌乳期的母猪补充充足的营养,确保其健康的体质显得尤为重要,在后备母猪阶段就应该着手增加营养的准备工作（图1）。     

母猪开配体重对其头胎繁殖性能的影响

目的:研究母猪开配体重对其头胎繁殖性能的影响,找出适宜的开配体重。方法:数据采自福建省某种猪场2012~2013年补充的995头后备母猪生产记录,按母猪开配体重分为110~120kg、120~130kg、130~140kg、140~150kg、150~160kg和160~170kg组,并对其头胎产总仔数、头胎产健仔数和头胎产死仔数进行统计分析。结果:母猪在130~140kg体重开配,其头胎产总仔数和头胎产健仔数最高,分别为12.10头和11.53头,与其它开配组相比差异显著(P0.05);母猪在110~120kg体重开配,其头胎产总仔数和头胎产健仔数最低,分别为10.56头和9.35头;母猪在110~120kg体重开配,其头胎产死仔数最高,为0.47头,与其它开配体重组相比差异显著(P0.05)。结论:后备猪的开配体重对母猪头胎繁殖性能有一定影响,在适宜的日龄下,母猪在130~140kg体重下开配有利于其头胎繁殖性能的充分发挥。     

母猪的营养与繁殖

由于畜牧学相关学科的进展,母猪的繁殖性能已经有了显著的改善。这些改善在一定程度上归因于对繁殖母猪的营养需要有了更多的了解。本文旨在介绍最近有关高产母猪营养需要方面取得的一些进展,以及可满足这些营养需要的一种日粮配合方法。 妊娠期 母猪繁殖周期的各个阶段是相互联系的。繁殖周期中一个阶段的营养水平会影响下一个阶     

母猪无乳综合症的防治

母猪分娩后及在泌乳期,由于多种原因,引起乳腺机能紊乱,产乳量显著减少甚至完全无乳,此病多发于初产母猪和老龄母猪,在我镇山区广大农户中常有发生,给仔猪生产造成了严重的损失.     

农户养地方猪种母猪初配体重对繁殖力的影响试验

山区农户养地方种6月龄母猪按体重不同分为两组,每组各8头,对照组母猪初配体重为28.5±3.04千克,试验组母猪初配体重为37.5±3.45千克。在农村常规条件下,结果表明:(1)对照组母猪体重始终低于试验组,且没有快速生长而赶上的势头,试验组在第三胎仔猪断奶时体重为92±5.32千克,比对照组75±5.71千克仍有17千克的差距。(2)试验组在第一情期受胎率高达83.33％,比对照组62.5％高出20.83％(P<0.01)。(3)试验组三胎平均总产仔数、活产仔数、60日龄活仔数分别高于对照组14.9％(P<0.05)、10.8％(P<0.05)、13.3％(P<0.05)。(4)试验组初生窝重、60日龄窝重同对照组间均有明显差别(P<0.05)。(5)对照组母猪断奶至发情天数为9.4±14.2天,试验组只有6.47±2.5天,缩短2.93天。     

对哺乳母猪营养的研究热点

泌乳期营养负平衡会导致母猪(特别是初产母猪)泌乳量降低并影响下个繁殖周期的生产性能。哺乳母猪泌乳量和乳中的组成成分取决于采食饲料的数量和质量,而泌乳量和乳的质量又直接影响仔猪断奶体重和存活率,母猪的低泌乳能力可直接导致乳猪营养缺乏、生长滞缓、死亡率增加,影响仔猪断奶体重,加剧仔猪断奶应激并影响其     

防止母猪二胎繁殖性能下降的措施

约50%母猪的二胎仔猪出生窝重低于头胎仔猪出生窝重,而且最近研究发现:二胎仔猪出生窝重大小与以后胎次仔猪出生窝重大小及母猪分娩率有很大关系。然而,养猪生产者可以通过改变猪场管理和母猪营养来逆转这一趋势,从而提高母猪二胎及以上胎次的繁殖性能。     

给青年母猪提供更多赖氨酸

根据新信息，有些形成已久的培育繁殖青年母猪的营养策略也许要修改。尤其受到挑战的是这一概念：为增加青年母猪繁殖生涯开始时体脂的贮备，高能量、低蛋白的日粮对青年母猪是最适合的。根据这一概念，母猪体脂不足会影响随后的繁殖功能和繁殖性能。产第1窝仔猪的母猪，     

Genetic, phenotypic and environmental relationships between sow body weight and sow productivity traits

Yorkshire and Duroc litter records were used to estimate genetic, phenotypic and environmental relationships between sow body weight and sow productivity traits. Two data sets with two subsets each were used to complete this study; 663 and 460 records included litter traits only, while 522 and 359 records also contained sow body weight for Yorkshires and Durocs, respectively. Heritability estimates for number born (NB), number born alive (NBA), total birth weight of live pigs (BWLIT), litter weight at 3 wk (WT3WK), sow weight at parturition (WTDAMPAR) and sow weight at weaning (WTDAMWN) were .24 +/- .14, .21 +/- .14, .42 +/- .16, .19 +/- .14, .72 +/- .21 and .42 +/- .18, respectively, for Yorkshires and .05 +/- .10, .04 +/- .10, .21 +/- .14, .25 +/- .15, .85 +/- .25 and .87 +/- .26, respectively, for the Durocs. Repeatability estimates for NB, NBA, BWLIT, WT3WK, WTDAMPAR and WTDAMWN were .13 +/- .06, .17 +/- .06, .27 +/- .06, .13 +/- .06, .64 +/- .05 and .54 +/- .05, respectively, for Yorkshires and .17 +/- .06, .21 +/- .06, .14 +/- .06, .17 +/- .06, .28 +/- .07 and .39 +/- .07, respectively, for Durocs. Genetic correlations among litter traits were high and positive in the Yorkshire data. Genetic correlations between NBA and WTDAMPAR, NBA and WTDAMWN, WT3WK and WTDAMPAR, and WT3WK and WTDAMWN were .37 +/- .25, .18 +/- .34, .60 +/- .29 and .29 +/- .45, respectively, in the Yorkshire data. Genetic correlations among litter traits in the Duroc analysis had large standard errors but were generally similar to the estimates obtained from the Yorkshire data. The genetic correlation between WTDAMPAR and WTDAMWN was .93 +/- .09 for Yorkshire sows. The primary conclusion from this study is that as selection increases sow productivity traits, there will be a positive correlated response in sow body weight.     

Effects of salinomycin on sow weight change during lactation and on sow reproductive performance

Forty-five gravid cross-bred sows (mean parity 3.3 +/- .3) were randomly allotted to two dietary treatments: corn-soybean mean (CS) or CS plus 60 mg salinomycin per kilogram of diet (CSS). Sows were fed their respective diets through two successive parities with dietary treatment initiated at 100 d postcoitum and continued until weaning of the second successive litter. Therefore, sows fed CSS received salinomycin for 14 d before the first parturition and for approximately 153 d before the second parturition. Daily feed intake was restricted to 2 kg.hd-1.d-1 during gestation and to 3 kg.hd-1.d-1 from weaning to breeding. All sows. had ad libitum access to feed during lactation. Sows were weighed 7 d prior to parturition, at weaning and at breeding. Weaning-to-estrus interval and farrowing interval were recorded for all sows. Litters were weighed at birth and weaning. There were no differences (P greater than .05) between dietary treatments in sow weights before parturition, at weaning or at breeding for either first or second farrowing. The CSS-fed sows lost more weight from weaning to breeding after the first (P less than .03) and second (P less than .05) lactation periods than CS-fed sows. The CSS-fed sows tended to gain more (P = .06) weight during lactation than CS-fed sows. There were no differences (P greater than .05) between treatments in lactation feed intake, weaning-to-estrus interval, farrowing interval, litter size born or weaned, litter weights at birth or at weaning, or in sow culling rate.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of sow parity and weight at service on target maternal weight and energy for gain in gestation

The objective of this study was to evaluate targeted maternal weight gains in sows by parity group during gestation. Weight and backfat gains during gestation by parity, weight, and backfat groups also were analyzed. The data evaluated were a subset (374 sows) of a larger experiment that compared three methods of feeding sows during gestation on weight and backfat gains and subsequent reproductive performance. Feed allowances were based on modeled calculations of energy and nutrient requirements to achieve target sow maternal weight and backfat gains. Actual backfat gain for gilts and sows was regressed on maternal weight gain and estimated energy available for gain. The regression equations were then used to predict maternal weight gains for target backfat gains for three parity groups (gilts, Parity 1 and 2 sows, and Parity 3 and older sows). For gilts and Parity 1 and 2 sows, much greater target maternal weight gains are required to achieve 6 and 9 mm of backfat gain, whereas Parity 3 and older sows require maternal weight gains similar to those targeted to achieve the desired backfat gain. Given similar energy intake levels above maintenance, gilts gained more weight than multiparous sows, as gain was based more on protein and less on fat and thus was more efficient. Gilts required more maternal weight gain than sows to achieve similar backfat gains due to the higher protein and low fat contents of gain in younger, lighter sows compared with older parity sows. Low-backfat sows that needed to gain large amounts of backfat failed to achieve these large gains. We speculate this failure may be due to lower tissue insulation levels with the low backfat levels and higher activity levels of these sows compared with high-backfat sows. It seems that both parity and weight are individually important factors that influence energy and nutrient requirements for gestation in the modern sow.     

影响母猪产仔数和仔猪初生重的因素

繁殖率是反映母猪繁殖力和猪场生产管理水平的重要经济参数。通常衡量母猪群生产性能的指标是每头母猪每年提供的断奶仔猪数,主要有两部分组成,即年母猪产仔窝数和母猪每窝的断奶仔猪数。据生产实践,有许多因素影响着母猪的生产性能,包括遗传因素、环境因素、饲养管理因素等。饲养母猪,只有年产仔窝数多,     

种蛋非线性失水的好处

箱体式孵化的一个主要的好处在于可以应用种蛋的非线性失重系统,该系统要求孵化前9 d孵化箱的通风可以减弱而在后9 d逐渐增加。     

母猪妊娠期营养对窝产仔猪初生重整齐度的影响

母猪窝产仔猪初生重整齐度差导致生猪生产效率降低,研究母猪妊娠期间营养需求满足母猪和胎儿营养需要对提高生猪生产效率和增加窝产仔猪初生重的整齐度具有重要意义。然而,母猪妊娠期间营养水平对仔猪初生重整齐度影响的报道很少。本文分析影响仔猪初生重差异的因素及其机制,旨在为寻找提高窝产仔猪整齐度的营养战略提供帮助。     

Genetic determination of individual birth weight and its association with sow productivity traits using Bayesian analyses

Genetic association between individual birth weight (IBW) and litter birth weight (LBW) was analyzed on records of 14,950 individual pigs born alive between 1988 and 1994 at the pig breeding farm of the University of Kiel. Dams were from three purebred lines (German Landrace, German Edelschwein, and Large White) and their crosses. Phenotypically, preweaning mortality of pigs decreased substantially from 40% for pigs with < or = 1 kg weight to less than 7% for pigs with > 1.6 kg. For these low to high birth weight categories, preweaning growth (d 21 of age) and early postweaning growth (weaning to 25 kg) increased by more than 28 and 8% per day, respectively. Bayesian analysis was performed based on direct-maternal effects models for IBW and multiple-trait direct effects models for number of pigs born in total (NOBT) and alive (NOBA) and LBW. Bayesian posterior means for direct and maternal heritability and litter proportion of variance in IBW were .09, .26, and .18, respectively. After adjustment for NOBT, these changed to .08, .22, and .09, respectively. Adjustment for NOBT reduced the direct and maternal genetic correlation from -.41 to -.22. For these direct-maternal correlations, the 95% highest posterior density intervals were -.75 to -.07, and -.58 to .17 before and after adjustment for NOBT. Adjustment for NOBT was found to be necessary to obtain unbiased estimates of genetic effects for IBW. The relationship between IBW and NOBT, and thus the adjustment, was linear with a decrease in IBW of 44 g per additionally born pig. For litter traits, direct heritabilities were .10, .08, and .08 for NOBT, NOBA, and LBW, respectively. After adjustment of LBW for NOBA the heritability changed to .43. Expected variance components for LBW derived from estimates of IBW revealed that genetic and environmental covariances between full-sibs and variation in litter size resulted in the large deviation of maternal heritability for IBW and its equivalent estimate for LBW. These covariances among full-sibs could not be estimated if only LBW were recorded. Therefore, selection for increased IBW is recommended, with the opportunity to improve both direct and maternal genetic effects of birth weight of pigs and, thus, their vitality and pre- and postnatal growth.