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1.
统计分析了2001年引进的新美系杜洛克种猪及繁殖后代在6月龄、12月龄、24月龄和36月龄四个阶段的体尺、体重数据,结合品种特征、体型外貌总结研究出杜洛克种猪的百分制评分及等级标准。  相似文献   
2.
为研究不同品系杜洛克作为终端父本对其后代商品猪胴体性状的影响,选取214和108头分别由美系和加系杜洛克公猪配种、出生时间相近(±2 d)和体重相近(35±5 kg)的后代三元商品猪进行育肥饲养,结束饲养后开展屠宰试验,测定背膘厚度、眼肌厚度、瘦肉率和肋骨数。结果显示:加系杜洛克商品后代的背膘厚度、眼肌厚度显著(P<0.05)高于美系杜洛克后代商品猪;加系杜洛克后代商品猪的瘦肉率、肋骨数显著(P<0.05)低于美系杜洛克。同一品系不同性别间背膘厚度、眼肌厚度、瘦肉率均不显著(P>0.05),加系商品公猪肋骨数极显著低于母猪肋骨数(P<0.01)。结论:美系杜洛克后代商品猪的胴体性状优于加系杜洛克后代商品猪。  相似文献   
3.
This study investigated the effects of amino acids (AA) supplementation in low crude protein (CP) diets on growth performance and carcass characteristics in finishing gilts. One hundred and eighty gilts (59.1 ± 5.1 kg) were randomly allotted to one of five diets which consisted of a high CP (15.6%) diet or four low CP (11.6%) diets for 50 days. The low CP diets were supplemented with lysine + threonine + methionine (LCM), LCM + tryptophan (LCT), LCT + valine (LCV) or LCV + isoleucine (LCI), respectively. Gilts were housed at six pigs per pen with six pens per treatment. At the end of the 50‐day experiment, 30 gilts (one pig per pen) with average body weight (BW) of 98 kg were killed to evaluate carcass traits. The pigs fed the diet supplemented with LCV obtained the highest average daily gain (ADG), which was higher than those of pigs fed the diet supplemented with LCM (P < 0.05). Dietary supplementation with tryptophan, valine and isoleucine in low CP diets increased ADG (linear and quadratic effect, P < 0.05), serum levels of valine (quadratic effect, P < 0.05) and isoleucine (linear and quadratic effect, P < 0.05) and immunoglobulin G (IgG) and IgA (linear and quadratic effect, P < 0.05) in finishing gilts. © 2016 Japanese Society of Animal Science  相似文献   
4.
We estimated heritabilities of semen production traits and their genetic correlations with litter traits and pork production traits in purebred Duroc pigs. Semen production traits were semen volume, sperm concentration, proportion of morphologically normal sperms, total number of sperm, and total number of morphologically normal sperm. Litter traits at farrowing were total number born, number born alive, number stillborn, total litter weight at birth, mean litter weight at birth, and piglet survival rate at birth. Litter traits at weaning were litter size at weaning, total litter weight at weaning, mean litter weight at weaning, and piglet survival rate from birth to weaning. Pork production traits were average daily gain, backfat thickness, and loin muscle area. We analyzed 45,913 semen collection records of 896 boars, 6,950 farrowing performance records of 1,400 sows, 2,237 weaning performance records of 586 sows, and individual growth performance records of 9,550 animals measured at approximately 5 mo of age. Heritabilities were estimated using a single-trait animal model. Genetic correlations were estimated using a 2-trait animal model. Estimated heritabilities of semen production traits ranged from 0.20 for sperm concentration to 0.29 for semen volume and were equal to or higher than those of litter traits, ranging from 0.06 for number stillborn and piglet survival rate at birth to 0.25 for mean litter weight at birth, but lower than those of pork production traits, ranging from 0.50 for average daily gain to 0.63 for backfat thickness. In many cases, the absolute values of estimated genetic correlations between semen production traits and other traits were smaller than 0.3. These estimated genetic parameters provide useful information for establishing a comprehensive pig breeding scheme.  相似文献   
5.
选择日龄、体况较一致的二元杂(长白×约克)后备母猪27头,采用L9(34)正交表安排试验,共9个试验组,每组3个重复。饲粮锌、硒和维生素E均设置3个水平,分别为:锌(45.0mg/kg,85.0mg/kg,125mg/kg);硒(0.10mg/kg,0.25mg/kg,0.40mg/kg);维生素E(15IU/kg,30IU/kg,45IU/kg),目的是研究饲粮微量元素锌、硒和维生素E对后备母猪生长发育和血清生殖激素参数的影响规律。结果表明在喂给含锌量85mg/kg,含硒量0.25mg/kg,含维生素E量45IU/kg饲粮时:(1)后备母猪的初次发情时间最早,分别为(187.4±6.6)d,(185.9±8.4)d,(189.1±7.3)d(P<0.05);(2)血清雌激素及孕激素浓度在不同日龄情况下均显示最高水平(P<0.05或P<0.10)。综合所考察的参数,后备母猪饲粮中含锌85mg/kg,含硒0.25mg/kg,含维生素E45IU/kg是适当的组合用量。  相似文献   
6.
采用15N-甘氨酸单剂量终产物法研究了妊娠和非妊娠母猪在不同阶段整体蛋白质代谢的周转速率以及氨基酸利用效率的差异。结果表明:刚配种时,妊娠母猪与非妊娠母猪蛋白质代谢参数差异不显著(P>0.05);妊娠30d时,妊娠母猪蛋白质合成速率,降解速率、周转速率显著低于非妊娠母猪(P<0.05),但沉积速率提高了25%(P<0.05);妊娠后期,妊娠母猪氨基酸代谢库氮流量、周转速率以及蛋白质合成速率和降解速率显著(P<0.01)提高,蛋白质的沉积速率增加了71.1%(P<0.01)。  相似文献   
7.
以苏姜猪为试验素材,对初生及15、30、45、60、75日龄小母猪消化器官生长发育与血液胃肠激素水平变化的相关性进行研究。结果表明:苏姜小母猪早期激素水平变化呈明显的规律性,初生时生长抑素含量较高,随后呈下降趋势,而生长激素和胃泌素)在75日龄内呈规律性变化。生长激素对消化器官的生长有促进作用,而生长抑素则抑制消化器官的生长。  相似文献   
8.
MUC13是控制仔猪大肠杆菌 F4ac易感或抗性的主效基因。该研究利用分子育种与常规育种技术、闭锁继代与开放选育相结合的综合方法,对250头杜洛克育种核心群实施连续3个世代的基因检测和性能测定,筛选出 MUC13抗性纯合基因型种群。经测试,在相同饲养管理条件下,哺乳期的同胎次20窝育种群母猪与20窝扩繁群母猪相比,断奶前仔猪腹泻发生率分别为8.7%和18.4%(P<0.01),但断奶成活率两组间差异未达到显著水平(P>0.05);对育种群3个世代的测定选育结果分析发现,第1和第3世代间达100 kg体质量日龄差异不显著( P>0.05)、但活体背膘厚相比减少1.46 mm(P<0.05),同时还发现,3个世代中 MUC13不同基因型个体间生长速度和活体背膘差异均不显著( P>0.05)。综上说明,MUC13基因抗性纯合有利于防止仔猪腹泻的发生并能有效降低活体背膘,但对生长发育没有明显影响。  相似文献   
9.
10.
The effect upon the reproduction of total resection of the oviductal isthmus, including the uterotubal and ampullary-isthmus junctions followed by end-to-end ampullo-cornual anastomosis was studied in pigs. Normal cycling gifts of proved fertility were submitted to bilateral isthmus deletion (Group I). Other gilts were submitted only to unilateral isthmic resection, while their contralateral medial isthmus was transversally cut and reanastomosed (Group II). A significantly lower nidation index was obtained after bilateral isthmic resection. The gilts in Group I which did not become pregnant and those in Group II were successfully mated during forthcoming standing oestruses, and were in association to that slaughtered on days 3, 4, or 5 of the cycle, and the characteristics and location of ova were determined. Spermatozoa fertilized the ova, and those cleaved normally in the isthmic-resected tube as well as in the sham-operated oviducts. The isthmic-resected oviduct, however, did not transport cleaved ova into the uterus at the time expected as normal. The findings suggest that the fertilized pig ova cannot reach the uterus at the normal expected time in case of total absence of the isthmic part of the oviduct, resulting in impaired fertility.  相似文献   
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