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81.
An experiment was conducted to investigate the effect of dietary betaine supplementation on carcass characteristics, hormones, growth factor and lipid metabolism in finishing pigs. Forty-eight crossbred barrows and gilts (Seghers × Seghers × Duroc) weighing about 55 kg were divided into two groups, each with three replicates of eight pigs (four barrows and four gilts) per replicate, and fed corn–soybean meal basal diets supplemented with 0 and 0.125% betaine for 42 days. At trial termination, two pigs (one barrow and one gilt) weighing about 90 kg were selected from each replicate and slaughtered for analyses. The results showed that betaine increased carcass lean percentage and longissimus muscle area by 5.19% (P < 0.01) and 17.85% (P < 0.01), respectively, and decreased carcass fat percentage and average backfat thickness by 13.07% (P < 0.01) and 10.30% (P < 0.05), respectively. Serum growth hormone, insulin-like growth factor I, free triiodothyronine, free thyroxine and insulin levels in pigs fed betaine were elevated by 45.61% (P < 0.01), 55.50% (P < 0.01), 57.95% (P < 0.01), 51.80% (P < 0.01) and 42.34% (P < 0.05), respectively. Fatty acid synthase activity in the 10th rib subcutaneous adipose tissue was decreased by 24.35% (P < 0.05) with betaine supplementation, whereas hormone-sensitive lipase activity was significantly increased (P < 0.05). Meanwhile, serum free fatty acids concentration in betaine-fed pigs was 25.75% higher compared to controls (P < 0.01). The study suggested that betaine could induce changes in hormones and growth factor in finishing pigs, and therefore could inhibit fat synthesis through reducing lipogenic enzymes activities and promote fat degradation by increasing hormone-sensitive lipase activity, with a resultant decrease in adipose tissue mass and improvement in carcass characteristics.  相似文献   
82.
将48头杜×长×大三元杂交生长猪随机分为两组,分别饲喂正常磷水平日粮和无磷酸氢钙日粮,结果表明:与正常磷水平日粮相比,无磷酸氢钙日粮可显著提高磷的表观消化率(P<0.05),增加猪场的纯收入,减少粪中磷的排放以保护猪场周边的生态环境。  相似文献   
83.
The effect of different types of fibre on the intestinal digesta and microbial diversity was evaluated in growing pigs. The animals were fed during forty-two days with one of four experimental diets including a control group, a diet enriched with resistant starch type I, by coarse ground corn, and other two diets containing sugar beet pulp (8%) and wheat bran (10%) (as sources of soluble and insoluble non-starch polysaccharides respectively). Body weight (BW) and average daily feed intake (ADFI) were assessed at day 7, 21 and 42. Luminal samples of digesta from proximal colon were collected to analyse water retention capacity (WRC), concentration of short-chain fatty acids (SCFA) and the microbial diversity. Overall, animals fed with higher amounts of non-digestible carbohydrates had lower ADFI and BW. Sugar beet pulp provoked an increase of WRC, a higher concentration of SCFA, and a more stable microbial diversity throughout the experimental period. On the other hand, animals fed with wheat bran presented a lower bacterial diversity.  相似文献   
84.
In order to identify the molecular markers related to alive litter size of Bama Xiang pigs,the genome-wide association study (GWAS) was used to map and screen the candidate genes affecting the alive litter size trait.Ear tissue samples of 297 Bama Xiang pigs with multiple parity records were collected,and DNA was extracted and genotyped by porcine 50K SNP beadchip.After quality control and genotype imputation,the alive litter size of Bama Xiang pigs were GWAS by Tassel.The results showed that the average number born alive per litter of Bama Xiang pigs increased gradually with the increasing of parity in the range of 1-9 parities.A total of 32 816 SNPs were obtained after quality control and filtration.8 SNPs related to alive litter size of Bama Xiang pigs were screened by genome-wide association analysis,which were significant at genome or chromosome level.Based on the enrichment analysis of the coding genes in the region between 500 kb upstream and downstream of the associated significant SNP loci,and the QTL regions and gene functions related to porcine reproductive traits,4 genes (CAPZB,MSH3,CITED2 and HSD17B7) were finally identified to be candidate genes related to alive litter size of Bama Xiang pigs.  相似文献   
85.
选用平均体重29.6kg的三元杂(杜×大×长)生长猪144头,按随机区组设计分为6个处理。饲粮中分别添加0、100、200mg/kg硫酸铜、200mg/kg碱式氯化铜、100mg/kg小肽铜、100mg/kg复合氨基酸螯合铜(以铜含量计)。结果表明:100mg/kg小肽铜和100mg/kg复合氨基酸螯合铜均能有效提高生长猪日增重和日采食量,其促生长效果与200mg/kg硫酸铜无显著(P〉0.05)差异,而粪中铜含量分别下降了36.8%和48.4%(P〈0.05)。  相似文献   
86.
96头始重(24.14±1.12)kg的杜长大三元杂交猪,随机分为4组。第1组为对照组,饲喂基础日粮(含氟量37.39mg/kg),第2、3、4组分别饲喂含氟(以NaF形式添加)量为100、150、200mg/kg的日粮,研究日粮中不同氟水平对猪生长性能和血清某些生化指标的影响,并探讨了氟在肝、肾和肌肉中的沉积,饲料氟和粪氟、血清氟、尿氟之间的相关关系。结果表明,第3、4组猪增重与对照组相比分别降低8.86%(P<0.05)和9.81%(P<0.05),料重比分别升高7.36%(P<0.05)和8.07%(P<0.05)。第4组血清钙、镁、白蛋白含量和碱性磷酸酶的活力与对照组相比分别降低了17.33%(P<0.01)、29.91%(P<0.01)、10.75%(P<0.05)和33.71%(P<0.01)。第3、4组肝、肾和肌肉氟含量与对照组相比显著增加(P<0.05)。各试验组粪氟、血清氟、尿氟含量随饲料中氟含量的增加而升高,且各组间差异极显著(P<0.001),饲料氟与粪氟、血清氟、尿氟含量相关系数分别为0.943(P<0.01)、0.911(P<0.01)和0.959(P<0.01)。  相似文献   
87.
膨化与加酶玉米对断奶仔猪生长性能和肠黏膜形态的影响   总被引:1,自引:0,他引:1  
通过2个饲养试验,研究了膨化及加酶处理玉米对断奶仔猪的生长性能和肠黏膜形态的影响。试验一分别用普通玉米、膨化玉米、普通玉米加酶及膨化玉米加酶为主要能量原料的饲料饲喂仔猪做4种处理,每个处理6个重复,定时记录体质量和耗料量.计算日增重、日采食量和料肉比。结果表明,膨化和加酶玉米均可提高日增重,降低料肉比。试验二分别用普通玉米、膨化玉米、普通玉米加酶及膨化玉米加酶为主要能量原料的饲料饲喂仔猪做4种处理,每个处理6个重复,分别在断奶后第14天和第28天各屠宰1头公猪。取十二指肠、空肠前、中、后段以及回肠做组织切片,观察其黏膜厚度、绒毛高度、隐窝深度和绒毛宽度。结果表明,断奶后14d,与普通玉米组相比,膨化玉米组和加酶玉米组都显著提高了十二指肠的绒毛高度,二者共同处理组使十二指肠的绒毛高度极显著提高;2种处理组都显著降低了空肠中段的隐窝深度;显著增加了十二指肠、空肠前段、后段和回肠的黏膜厚度。断奶后28d,2种处理组都显著增加了十二指肠的黏膜厚度。  相似文献   
88.
对猪体细胞克隆技术中关键步骤之一的去核方法作了较深入的研究。结果表明,由本实验室改进的Willadsen去核法——二步挤压去核法,无论在去核操作成功率(73.9%)上还是在去核效率(81.2%)上都明显好于McGrath-Solter去核法(42.5%、67.4%,P〈0.05);同时,本试验还发现,卵母细胞成熟培养36h后去核组去核效率(89.1%)显著地高于成熟培养44h后去核组(55.8%,P〈0.05),而核移植重构胚的发育率2个组间无显著差异。  相似文献   
89.
The objective of this study was to determine if selection response for increased litter size in pigs could be partially attributed to three type 1 marker loci coding for genes known to affect litter size: oestrogen receptor (ESR), retinol‐binding protein 4 (RBP4) and follistatin (FS). In the high litter size line (LS), pigs from the largest litters, based on number of pigs born alive (NBA), were retained to parent the next generation. A randomly selected control line (LC) was maintained. Gilts were reared in litters of 10 pigs or less to minimize maternal effects. Pigs were measured at generations 10–12. Additional traits scored were number of fully formed pigs (NFF) and number of mummified fetuses (MUM). Breeding values for NFF and NBA were greater (p < 0.05) in LS than LC in generations 11 and 12, but no significant line differences were found for MUM. The A allele of the ESR locus was fixed in both lines. After adjustment for effects of genetic drift, frequency of the two alleles segregating for the FS and RBP4 loci did not differ significantly between lines. No significant additive or dominance effects of the FS markers were detected for NFF, NBA and MUM in either LS or LC. Response to selection for increased litter size could not be attributed to effects at the ESR, RBP4 or FS loci.  相似文献   
90.
优质猪杂交繁育体系的构建与优化   总被引:2,自引:0,他引:2  
选用杜洛克、长白、大白3个国外引进品种,冀合白猪专门化母系B1个国内培育品系,以及1个地方品种太湖猪,模拟杂交繁育体系的生物经济学过程,构建了优质猪的杂交繁育体系,并以每头后备母猪平均每年的利润、每头标准化商品猪的利润、每1000头标准商品猪相对应的母猪头数和商品代出栏猪肌内脂肪含量(肉质指标)4个评价指标对杂交繁育体系进行了优化选择,结果在4种杂交配套组合中,杜洛克×(大白×冀合白猪专门化母系B)经济效率和商品代猪肉质最优。  相似文献   
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