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1.
选用半舍饲的周岁龄青海细毛羊５６只，分为三组，试验１、２组各２０只，对照组１６只。在同等饲养管理条件下，试验１、２组每只羊每日分别添加０．２ｇ和０．１ｇＲＣＦ－３稀土添加剂，进行６０ｄ饲养试验。结果：试验１、２组绵羊平均日增重分别比对照组提高３０．６％（Ｐ＜０．０１）和１２．６％（Ｐ＞０．０５）；平均羊毛长度分别比对照组提高２２．１％（Ｐ＜０．０１）和５．５％（Ｐ＞０．０５）；经济效益分别比对照组提高２５．２％（Ｐ＜０．０１）和８．７％（Ｐ＞０．０５％）。试验１组平均日增重，羊毛长度和经济效益分别比２组提高１５．９％（Ｐ＜０．０５）、１５．７％（Ｐ＜０．０５）和１５．２％（Ｐ＜０．０５）以试验１组的效果为佳。 相似文献
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对虾饵料中氨基酸的含量与比例对中国对虾生长的影响 总被引：3，自引：1，他引：2
本试验采用了五种饵料配方养殖中国对虾，结果是以虾体氨基酸含量与比例为标准配合的对虾饵料（配方１和配方４）和与蛤仔氨基酸含量与比例为标准配合的对虾饵料（配方２）相比，差异显著（Ｐ＜０．０５），与市场出售的饵料（对照１）相比差异极显著（Ｐ＜０．０１）。添加人工合成的蛋氨酸求得对虾饵料氨基酸平衡，并用ＰＶＡ－缩醛包裹（配方４），可明显提高养殖效果，与氨基酸的含量及比例虽然相同，但不用ＰＶＡ－缩醛包裹的配方３和配方５相比，差异显著（Ｐ＜０．０５）。与饲喂鲜活的蛤仔（对照２）相比，差异不显著（Ｐ＞０．０５）。与配方１相比，差异不显著（Ｐ＞０．０５），但配方４因添加人工合成氨基酸而减少动物性蛋白的用量，降低了成本，经济效益高。 相似文献
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人红细胞生成素转基因小鼠乳腺生物反应器的建立 总被引：3，自引：1，他引：2
将 ２．４ ｋｂ 的人红细胞生成素（ｈ Ｅ Ｐ Ｏ）基因组基因（ｇ Ｄ Ｎ Ａ）ｍ ｉｎｉｇｅｎｅ 克隆于 ０．９７７ ｋｂ 大鼠乳清酸蛋白（ Ｗ Ａ Ｐ）５′调控序列下游和 ０．８５ ｋｂ Ｗ Ａ Ｐ３′侧翼序列上游,构建了 ｈ Ｅ Ｐ Ｏ 乳腺定位表达载体 ｐ Ｗ Ａ Ｐ Ｅ Ｐ Ｏ Ｗ Ａ Ｐ３′ Ｕ Ｔ Ｒ（ｐ Ｗ Ｅ３′）。载体经 Ｓａｃ Ｉ Ｉ酶切、回收并纯化后作为目的基因,通过显微注射方法导入小鼠受精卵的雄原核,共注射 ５００ 枚卵,移植 ３００ 枚卵至 ２９ 只假孕母鼠输卵管内,获得仔鼠 ５５ 只。采取鼠尾,提取基因组。经 Ｐ Ｃ Ｒ 检测,阳性鼠 ２２ 只; Ｓｏｕｔｈｅｒｎ ｂｌｏｔｔｉｎｇ 检测,阳性鼠 １６ 只,其中 ９ 只母鼠,７ 只公鼠。将 １６ 只首建者小鼠分别与非转基因鼠交配,共获得 Ｆ１ 代仔鼠 １５７ 只。应用 Ｐ Ｃ Ｒ 方法对 Ｆ１ 代小鼠进行检测,结果首建者１ 号母鼠所生的 ６ 只仔鼠中有 ３ 只为阳性。与此同时,于 ９ 只雌性首建者分娩后第 １０ 天采奶,应用 Ｅ Ｌ Ｉ Ｓ Ａ 方法对乳汁中的 Ｅ Ｐ Ｏ 进行检测,结果 ６ 只母鼠获得表达,表达量为 ０．１２～１．５９ μｇ／ Ｌ。 相似文献
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设（年初头数＋年末头数）÷２×３６５为理论饲养头日，ａ、ｂ分别为补充率和更新率，ｃ_２、ｄ_１分别为下半年补充比和上半年更新比，实际饲养头日（Ｇ）与理论饲养头日（Ｎ）的差距［Ｓ＝（Ｇ－Ｎ）÷Ｎ］可按以下公式计算：当ａ＝ｂ、ｃ_２＝ｄ_１时，Ｓ＝０．５_ａ－２ｃ_２＝０．５ｂ－ｂｄ_１；当ａ≠ｂ、ｃ_２≠ｄ_１时，Ｓ＝［０．５（ａ＋ｂ）－ａｃｗ－ａｃ_２－ｂｄ_１］÷（２－ａ－ｂ）。实际饲养头日可按以下公式计算：Ｇ＝Ｎ±ＳＮ。 相似文献
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日粮中添加蜂花粉的试验组，与未添加的对照组，两组产蛋率分别为８７－７％ 和８０－２％ ，两组差异显著（Ｐ＜ ０－０５） ；平均蛋重分别为６２－５５±１－２２ｇ 和６２－５４ ±１－３１ｇ ，两组差异不显著（Ｐ＞ ０－０５） ；料蛋比分别为２－３５：１ 和２－５１：１，两组差异显著（Ｐ＜ ０－０５） ；试验组比对照组提高经济效益１５－７％ 。 相似文献
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用１６４只１周龄ＡＡ肉用仔鸡进行的两次试验结果显示，在含铜８—１４ｍｇ／ｋｇ的玉米—豆饼日粮中，添加１２５ｍｇ／ｋｇ铜（ＣｕＳＯ４５Ｈ２Ｏ），提高４—７周龄平均增重７．１－１０．８％（Ｐ＜０．０５或０．０１），提高１—３周龄平均增重２．１－２．５％（Ｐ＞０．０５，试验Ⅱ）或６．２％（Ｐ＜０．０１，试验Ⅰ），降低１—３周龄饲料／增重６．３－１５．３％，添加１２５ｍｇ／ｋｇ铜，对胸肌含水量无影响（Ｐ＞０．０５），明显提高了肝铜含量（Ｐ＜０．０５），但幅度不太大，由对照组的１３．８ｍｇ／ｋｇ提高到２３．８ｍｇ／ｋｇ（风干基础），而正常鸡肝含铜量低，因此对食品卫生无不利影响。大量铜由粪中排出体外，试验组粪铜浓度比对照组提高９倍。 相似文献
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通过５次６０４４只蛋鸡产蛋全程试验结果表明，无鱼粉全价饲料完全可以代替有鱼粉全饲料。平均产蛋率，平均蛋重试验组与对照组差异不显著（Ｐ＞０．０５），但试验组呈较好趋势，分别比对照组提高０．８－２．１和１．８－２．２个百分点之间；平均料蛋比试验组极显著地好于对照组（Ｐ＜０．０１）。 相似文献
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高纬度地区毛丝鼠繁殖规律的研究 总被引：1，自引：0，他引：1
本文对我国高纬度地区饲养的毛丝鼠进行了繁殖规律观察研究。结果表明，毛线鼠全年都可繁殖，相对集中在３￣１１月份；胎平均产仔１．９２只；年产２胎母鼠占４８．４６％；１￣４岁龄母鼠在繁殖上没有显著差异（Ｐ〉０．０５）；血配母鼠的繁殖率３３．７９％；仔鼠断奶活率９２．３％，育成率８１．３％。 相似文献
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L G Sheffield 《Journal of animal science》1991,69(3):1128-1132
Mice were administered caffeine (500 mg/liter of drinking water) from d 1 until d 18 of pregnancy. Before and after receiving caffeine, mice were given distilled water for drinking, as were controls. Litter size, birth weight, and offspring survival were not affected by caffeine, but litter weight on d 15 of lactation was increased by caffeine 84.0 +/- 3.1 g (n = 8) in controls vs 98.3 +/- 3.7 g (n = 7) in caffeine-treated mice (P less than .05). Mammary gland cell number, measured by the DNA content of mammae, was increased by giving caffeine during pregnancy (P less than .05). On d 18 of pregnancy, mammary DNA was .47 +/- .07 mg (n = 6) in controls vs .71 +/- .11 mg (n = 6) in caffeine-treated mice. On d 15 of lactation, mammary DNA was .96 +/- .12 mg (n = 8) in control vs 1.26 +/- .11 mg (n = 7) in caffeine-treated mice. RNA increased (P less than .05) parallel to DNA. In additional experiments, litters were cross-fostered and standardized to eight pups per litter. Mice were bred and caffeine was administered as described previously. At birth, eight pups from mice treated with caffeine or as controls during the preceding pregnancy were fostered to a control or caffeine-treated mother. In these experiments, litter weight on d 15 of lactation was 82 g for control litters nursing control mothers, 84 g for caffeine litters nursing control mothers, 96 g for control litters nursing caffeine mothers, and 99 g for caffeine litters nursing caffeine mothers (n = 7 per groups, pooled SE = +/- 3.4 g).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Comparison of rabbit breed types for postweaning litter growth, feed efficiency, and survival performance traits 总被引：1，自引：0，他引：1
Postweaning data on 643 rabbits from 122 litters representing four breed types, New Zealand White (NZW) and Californian (CAL) purebreds, CAL X NZW (CXN), and Flemish Giant (FG) crossbreds (the latter group was a collection of FG X CAL, FG X Champagne D'Argent [CHA], and 1/2 FG X 1/4 CAL X 1/4 CHA), were gathered over five seasons and compared for growth, feed efficiency, and survival-related performance traits. Evaluation criteria included litter size and weight at weaning (28 d); 28- to 70-d litter feed intake, weight gain, feed efficiency, and mortality rate; and litter and average market weight (70 d). The least squares model included main effects of breed type, season of birth of the litter and parity of dam, litter size at weaning as a linear covariate, and the random error. Breed-type differences were not detected for litter size and weight at weaning and feed efficiency. Purebred NZW and CAL litter trait performances were comparable (P greater than .05). Purebred NZW litters consumed less feed than CXN and FG crosses, gained weight less rapidly than FG crosses, and weighed less per fryer at 70 d than CXN and FG crosses (P less than .05). Feed intake was lower and average market weight was lighter for CAL purebred litters than for CXN and FG crossbred litters (P less than .05). The CXN and FG crossbreds only differed (P less than .05) for average market weight (2,078 vs 2,192 g). Mortality rate was lower (P less than .05) in CXN crossbred litters than in CAL purebred litters.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Characterization of straightbred and crossbred rabbits for milk production and associative traits 总被引：1，自引：0，他引：1
Two hundred twenty-five lactation and litter performance records from 82 does representing four genetic groups and two diets were analyzed to quantify breed, heterosis, reciprocal F1 cross and diet effects for milk production and associative traits. Doe genetic groups were New Zealand White (NN) and Californian (CC) straightbred and Californian X New Zealand White (CN) and New Zealand White X Californian (NC) reciprocal crossbreds. Pelleted diets fed to does and litters were either a commercial control or a 74% alfalfa diet. Three sire breeds of litters included NN, CC and Flemish Giant (FG) straightbreds. Doe genetic group and diet were important sources of variation (P less than .05) for all traits examined except for litter milk efficiency (litter gain/milk intake) and doe feed efficiency (milk yield/feed intake). The sire breed of litter effect did not influence (P greater than .05) lactational performance of does nor associative preweaning traits. Straightbred NN does were heavier at kindling, yielded more milk, reared a heavier litter by 21 d and were more efficient in converting feed into milk than were straightbred CC does (P less than .01). Significant heterosis was detected for milk production and for litter size and weight at 21 d. Reciprocal differences between crossbred doe groups were observed (P less than .05) for litter milk efficiency and doe feed intake. The 74% alfalfa diet was superior to the commercial control diet for effects on milk production and litter size and weight at 21 d, although doe feed intake was increased.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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波尔山羊繁殖性状遗传参数的估计 总被引：14，自引：0，他引：14
对 2 4 8窝波尔山羊的胎产羔数、羔羊初生重和 2月龄体重的资料进行了遗传分析。结果表明 :公羊和胎次均对母羊产羔数具有显著的影响(P <0 0 5)。不同产羔季节对羔羊初生重和 2月龄体重也具有显著影响。产羔数的遗传力为 0 1 52 ,属低遗传力 ,而羔羊初生重和 2月龄体重 2个性状 (0 433 ,0 347)有中等或较高的遗传力。波尔母羊胎产羔数与羔羊初生重、 2月龄体重之间存在显著或极显著的表型相关 ,但是它们之间却存在显著或极显著的负遗传相关 (P <0 0 5或 P<0 0 1 )。羔羊的初生重和 2月龄体重间 ,无论是表型相关还是遗传相关 ,都呈极显著的正相关(P <0 0 1 )。 相似文献
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试验旨在研究哺乳期补饲代乳品对仔猪生长性能、营养物质消化率及血清生化指标的影响,并探讨代乳品对缩短仔猪断奶日龄的可行性。选用120头（12窝）5日龄、平均体重（3.12±0.63）kg的仔猪,随机分为两组,每组60头（6窝,每窝为1个重复）。对照组补饲教槽料至28日龄断奶;试验组补饲代乳品和教槽料（代乳品：教槽料=1：1）至21日龄断奶,断奶后继续饲喂代乳品和教槽料至28日龄;28日龄后试验组和对照组饲喂相同日粮至70日龄。结果显示：①整个试验期,两组仔猪在5、21、28和70日龄时体重差异均不显著（P>0.05）;在5~21、22~28和5~28日龄阶段,试验组仔猪平均日采食量（ADFI）和料重比（F/G）均极显著或显著高于对照组（P < 0.01;P < 0.05）;而在22~28日龄阶段,试验组平均日增重（ADG）极显著低于对照组（P<0.01）。②试验组仔猪保育期的日粮总能（GE）、干物质（DM）、有机物（OM）和粗脂肪（EE）的消化率均显著高于对照组（P<0.05）。③在70日龄时,两组仔猪各项血清生化指标均无显著差异（P>0.05）。结果提示,补饲代乳品可显著增加哺乳期仔猪的采食量,同时促进保育期仔猪对日粮中营养物质的消化吸收。从保育期末体重来看,哺乳期补饲代乳品的仔猪提前至21日龄断奶是可行的。 相似文献
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Genetic differences in performance of dams were estimated by linear contrasts using means of two selected lines of mice and reciprocal F1's, F2's and backcrosses. The lines were selected for increased 6-wk body weight (W) or increased litter size (L). Genetic differences estimated were direct average (gD), direct heterosis (hD), maternal average (gM), progeny average (gP), and progeny heterosis (hP). For dam weight and feed consumption from 12 to 21 d postpartum (pp), gD was the largest genetic difference and favored line W. For litter size, litter weight at birth, litter efficiency (litter weight gain/dam feed consumption) from birth to 12 d pp and within litter mortality from 1 to 21 d pp, gD favored L and, except for hD in litter efficiency, was the most important genetic difference for these traits. Direct heterosis was the only significant difference for litter weight at 21 d pp, litter efficiency from 12 to 21 d pp and within litter mortality at parturition. The gM were larger in W than in L for dam weight and feed consumption, and for litter size and weight at birth, but they were usually of smaller magnitude than gD. The gP were significant only in litter traits measured before 12 d pp and favored W. For no trait measured was hP of consequence. Line differences in dam and litter weight accounted for genetic differences in dam feed consumption. Genetic differences in litter size at birth were not due to line differences in dam weight. The lower mortality within litters nursed by crossbred dams was responsible for hD on litter weight and litter efficiency. Within but not among lines, higher mortality rates were associated with larger litters. 相似文献
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Our objective was to estimate responses in reproductive traits in the Nebraska Index line (I) after 19 generations of selection for increased litter size. Responses were estimated in dams producing pure line, F1, and three-way cross litters. A total of 850 litters were produced over six year-seasons, including 224 pure line litters, 393 F1 litters produced from I and C females mated with Danbred NA Landrace (L) or Duroc-Hampshire (T) boars, and 233 litters by F1 L x I and L x C females mated with T boars. Contrasts of means were used to estimate the genetic difference between I and C and interactions of line differences with mating type. Farrowing rates of lines I (u = 91.0%) and C (u = 92.8%) did not differ. Averaged across all genetic groups, mean number born alive per litter was 10.1 pigs, and number and weight of pigs weaned per litter, both adjusted for number nursed and weaning age of 12 d, were 9.7 pigs and 34.4 kg, respectively. Averaged across mating types, direct genetic effects of I were greater than C (P < 0.05) for total born (3.53 pigs), number born alive (2.53 pigs), number of mummified pigs (0.22 pig), and litter birth weight (2.14 kg). The direct genetic effect of line I was less than C (P < 0.05) for litter weaning weight (-1.88 kg). Interactions of line effects with crossing system were significant (P < 0.05) for total number born, number of stillborn pigs, number weaned, and litter weaning weight. In pure line litters, I exceeded C by 4.18 total pigs and 1.76 stillborn pigs per litter, whereas the estimate of I-C in F1 litters was 2.74 total pigs and 0.78 stillborn pig per litter. The contrast between I and C for number weaned and litter weaning weight in pure litters was 0.32 pig and -0.28 kg, respectively, compared with 0.25 pig and -2.14 kg in F1 litters. Crossbreeding is an effective way to use the enhanced reproductive efficiency of the Index line. 相似文献
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选用高原瘦肉型母系猪白系哺乳仔猪25窝261头,随机按窝分为两组。试验组13窝139头仔猪2日龄,采用深部肌肉注射的方法,头均补给右旋糖苷铁1ml（含铁100mg）,对照组12窝122头不注射,在相同条件下哺乳至35日龄断奶。结果表明,试验组窝均成活8．6头,比对照组（7．8头）多0．8头,差异显著（P〈0．05）;断奶个体重分别为7．2kg和7．0kg差异不显著（P〉0．05）;窝均收入试验组比对照组提高13．3％,效益明显。 相似文献
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本试验将９～１０月龄新西兰繁殖母兔５０只和公兔６只，随机分为两组，试验组用塑膜暖棚饲养，对照组用普通兔舍饲养。试验结果表明，受胎率差异不显著（Ｐ＞００５）；窝产仔数、总产仔数、初生窝重差异显著（Ｐ＜００５）；４０日龄断奶窝重、仔兔成活率、经济效益差异极显著（Ｐ＜００１）。 相似文献