4种教槽料对断奶仔猪生长性能、腹泻率和皮毛指数的影响

试验选取160头体重相近的健康断奶仔猪,随机分4个处理,每个处理4个重复,每个重复10头。分别饲喂A料、B料、C料和D料,研究4种教槽料对断奶仔猪生长性能、腹泻率和皮毛指数的影响。其中A料和D料为粉料且含有血浆蛋白粉;B料和C料配方相同,均无血浆蛋白粉,只存在B料为粉料、C料为颗粒料的区别。结果表明：断奶后10d内A料组仔猪采食量和日增重均显著高于B料和C料组（P〈0.05）,与D料组差异不显著（P〉0.05）;B料和C料组采食量、日增重均差异显著（P〈0.05）。A料组仔猪料肉比与B料和c料组差异均显著（P〈0.05）,与D料相比,其料肉比降低4.76％。对于腹泻率和腹泻指数,A料和D料间差异不显著（P〉0.05）,但在B料和C料组间差异显著（P〈0.05）。除C料组皮毛指数与各组存在显著差异外（P〈0.05）,各组间均差异不显著（P〉0.05）。以上结果表明,粉料A和D生产效果相当,但均显著好于B料、C料。     

3种补铁剂对哺乳仔猪血红蛋白含量及其生长效果的影响

选用70头体重无显著差异的初生仔猪,随机分为5组,其中Ⅰ、Ⅱ、Ⅲ、Ⅳ组分别15头,第Ⅴ组10头。试验测定了不同补铁剂对Ⅰ、Ⅱ、Ⅲ组哺乳仔猪体内血红蛋白含量及仔猪生长效果的影响。结果表明,试验Ⅰ组(注射牲血素)哺乳仔猪体内血红蛋白含量较试验Ⅳ组(空白对照组)的高0.6 g/100 mL,组间差异不显著(P>0.05),而断奶重较试验Ⅳ组高0.94 kg,差异极显著(P<0.01)。试验Ⅱ组(注射牲血针)和试验Ⅲ组(注射血铁宝)的哺乳仔猪体内血红蛋白含量较试验Ⅳ组分别高1.1 g/100 mL和2.6 g/100 mL,与试验Ⅳ组相比差异极显著(P<0.01),断奶重较试验Ⅳ组分别提高了1.06 kg和1.69kg,差异极显著(P<0.01)。     

共轭亚油酸对14日龄断奶仔猪部分免疫指标的影响

为了确定共轭亚油酸(CLA)对14日龄断奶仔猪免疫功能的影响,进行了本试验。试验选用72头14 d断奶、体重为(4.04±0.04)kg的杜×(大×长)三元杂交仔猪,随机分成4个处理,每个处理3个重复,每个重复6头猪(公母各1/2)。调整各个处理的CLA和葵花籽油添加量(以CLA替代部分葵花籽油),使对照组不含CLA,试验组分别含0.5%、1.0%和1.5%CLA。饲养试验分3个阶段进行:14~28日龄为第1阶段,29~42日龄为第2阶段,43~56日龄为第3阶段。试验结果显示,试验第28天(42日龄),1.0%和1.5%CLA组血液PHA淋巴细胞转化率显著提高(P<0.05),所有试验组血清前列腺素E2(PGE2)水平显著低于对照组(P<0.05);试验第42天(56日龄),1.5%CLA组肿瘤坏死因子-α(TNF-α)水平显著高于对照组(P<0.05),1.5%CLA组仔猪血清PGE2显著降低(P<0.05);1.0%CLA组肝组织过氧化物酶体增殖物激活受体-γ(PPAR-γ)mRNA显著高于其他组(P<0.05),1.5%CLA组结肠黏膜PPAR-γmRNA显著高于其它组(P<0.05)。以上结果表明,饲粮中添加1.0%~1.5%的CLA能够有效提高超早期断奶仔猪的部分免疫指标。     

Short-chain fatty acid administration via water acidifier improves feed efficiency and modulates fecal microbiota in weaned piglets

This study examined the effect of a water acidifier containing free and buffered short-chain fatty acids (SCFA-WA) on growth performance and microbiota of weaned piglets. In total, 192 male piglets, approximately 4 wk of age, were allocated to 24 pens (12 per treatment) with 8 piglets per pen. The piglets received either regular drinking water (negative control) or drinking water with the acidifier supplied at 2 L/1,000 L. Body weight and feed intake were measured weekly on pen level. During the first 2 wk, daily visual assessment and scoring of the feces was conducted. Fecal samples of three piglets per pen were collected on days 14 and 42 for high-throughput sequencing analysis of the microbiota. Piglets offered SCFA-WA had significantly improved feed efficiency in the third week (P = 0.025) and over the whole study period (days 0 to 42, P = 0.042) compared with piglets in the negative control group, with a strong tendency observed during the first feeding phase (days 0 to 21, P = 0.055). Furthermore, the water acidifier group had a higher water intake than piglets provided with control water during the second feeding phase (days 21 to 42, P = 0.028) and over the whole study period (days 0 to 42, P = 0.043). There was no significant difference in body weight, average daily gain, or average daily feed intake (days 0 to 21, 21 to 42, 0 to 42). Furthermore, there was no overall significant difference in fecal scoring between the treatments. In terms of the fecal microbiota response, piglets offered the water acidifier showed a significantly higher relative abundance (RA) of genus Clostridium sensu stricto 1 and a lower RA of genus Streptococcus compared to the control. Furthermore, the redundancy analysis showed a positive association between improved feed efficiency and daily weight gain and RA of Butyricicoccus and Faecalibacterium. In conclusion, consumption of the water acidifier containing free and buffered SCFA modulated the microbiota and improved feed efficiency in piglets.     

载铜蒙脱石对断奶仔猪生长性能及血清免疫指标、抗氧化指标、炎症指标的影响

本试验旨在研究饲粮中添加载铜蒙脱石对断奶仔猪生长性能及血清免疫、抗氧化、炎症等生化指标的影响.选取72头(25±3)日龄、体重为(7.42±0.88)kg的健康仔猪(公母各半),按随机区组设计分为3组,每组4个重复,每个重复6头猪.3个处理分别为对照组、氧化锌+抗生素组及载铜蒙脱石组,对照组饲喂基础饲粮,氧化锌+抗生素...     

发酵豆粕对断奶仔猪生长性能、消化酶及肠道菌群结构的影响

【目的】本试验旨在探讨发酵豆粕(FSBM)对断奶仔猪生长性能、消化酶活性及肠道菌群结构的影响。【方法】试验选取48头21日龄断奶仔猪(杜×长×大,6.88 kg±0.13 kg),随机分为对照组和试验组,每组4个重复,每个重复6头猪。对照组饲粮为基础饲粮,试验饲粮用6%FSBM等量替代基础饲粮中的豆粕。试验期为20 d。试验期间记录采食量和体重。试验第21天,每个重复选取2头猪屠宰,收集回肠食糜测定消化酶活性和肠道菌群结构,并对两者进行相关性分析。【结果】(1)饲喂FSBM可显著提高断奶仔猪的终末体重和平均日增重(average daily gain, ADG),并显著降低了料重比(feed/gain, F/G)(P<0.05);(2)FSBM组断奶仔猪回肠中的胰蛋白酶和淀粉酶活性显著提高(P<0.05);(3)饲喂FSBM显著提高了断奶仔猪回肠食糜中拟杆菌门、普雷沃氏菌科NK3B31类群、厌氧弧菌属、瘤胃菌科UCG-005、普氏菌属2、巨型球菌属、副杆菌属、Solobacterium及毛螺菌科UCG-004的相对丰度,显著降低了链球菌属的相对丰度(P<0.05);(...     

Significant changes in caecal microbial composition and metabolites of weaned piglets after protein restriction and succedent realimentation

The present study aimed to investigate the effects of protein restriction and subsequent realimentation on caecal barrier function, caecal microbial composition and metabolites in weaned piglets. Thirty-six 28-day-old weaned piglets were randomly assigned to a control group and a treatment group. The piglets were fed diets containing 18.83% (normal) or 13.05% (low) of crude protein from the 1st to 14th day, after which all piglets were fed diets containing 18.83% of crude protein from the 15th to 28th day. The results showed that protein restriction increased caecal bacterial diversity and richness as well as the abundance of Ruminococcus 2, Faecalibacterium and Lachnospiraceae_uncultured, but reduced the abundance and the gene copies of Lactobacillus in the treatment group compared with the control group on day 14. Protein restriction also decreased the concentrations of isovaleric acid and total branched-chain fatty acids. During the succedent protein realimentation stage, the abundance of Ruminococcaceae UCG-014 and the concentrations of lactic acid, acetic acid, butyric acid and total short-chain fatty acids were increased in the treatment group on day 28. Furthermore, the ammonia concentration was reduced, while the gene mRNA levels of caecal barrier function were increased in the treatment group both on days 14 and 28. In conclusion, dietary protein restriction and realimentation could change caecal microbial composition and metabolites, and eventually influence caecal barrier function. The present study may provide a new insight into protein restriction and realimentation in weaned piglets.     

不同比例低蛋白氨基酸平衡日粮对断奶仔猪生长性能及氮平衡的影响

为了解不同比例低蛋白氨基酸平衡日粮对断奶仔猪生长性能及氮平衡的影响,试验将96头初始体重9.8 kg左右的杜×长×大断奶仔猪随机分成4个处理,每个处理分别饲喂含不同蛋白水平的玉米-豆粕型饲粮(20%CP、19%CP、18%CP和17%CP),通过补充合成氨基酸,使各处理组的氨基酸与要求相一致。正式试验期为28 d,测定断奶仔猪生长性能、氮平衡指标。结果表明,日粮蛋白水平降至18%时,不会影响断奶仔猪生长性能,且显著降低尿氮、粪氮和总氮排放量(P<0.01);但随着日粮蛋白水平进一步降至17%时,显著降低仔猪平均日增重(P<0.01),显著增加料重比(P<0.01);18%CP组与17%CP组总氮排放量、氮表观利用率、氮表观生物学效价差异不显著(P>0.05)。说明添加合成氨基酸满足断奶仔猪需要,将日粮蛋白水平降至18%,不仅不会影响仔猪生长性能,而且还会降低氮排放,减少环境污染。     

脂多糖刺激后不同时间断奶仔猪空肠上皮细胞铁死亡的变化规律

本试验旨在探究用脂多糖(LPS)刺激后不同时间断奶仔猪空肠上皮细胞发生铁死亡的变化规律。选取体重和遗传基础相近的21日龄杜×长×大断奶仔猪42头,饲喂基础饲粮14 d后,空腹注射LPS,按100μg/kg BW注射LPS后不同时间随机分为7个处理,分别于0、1、2、4、8、12、24 h屠宰取样,测定空肠上皮细胞铁死亡相关基因mRNA表达量以及抗氧化水平。结果表明:在LPS刺激后8 h,空肠上皮细胞铁死亡关键基因膜蛋白转铁蛋白受体1(TFR1)、热休克蛋白B1(HSPB1)、铁反应元件结合蛋白2(IREB2)和谷胱甘肽过氧化物酶4(GPX4)的mRNA表达量最高(P<0.05);在LPS刺激后2 h,胱氨酸/谷氨酸反向转运体亚基(SLC7A11)的mRNA表达量最高(P<0.05);在LPS刺激后8、12、24 h,空肠上皮细胞总抗氧化能力(T-AOC)和谷胱甘肽过氧化物酶(GSH-Px)活性均显著降低(P<0.05);在LPS刺激后8 h,谷胱甘肽(GSH)含量最低(P<0.05)。由此可见,在LPS刺激后8 h,断奶仔猪空肠上皮细胞铁死亡发生程度最为严重。     

不同来源大白猪总产仔数近交衰退评估

旨在评估两个不同来源大白猪群体经过近8个世代的选育后总产仔数（total number of piglets born，TNB）近交衰退的程度。本研究对1 937头大白猪使用GeneSeek GGP Porcine HD芯片进行分型，其中1 039头来自加系大白猪和898头来自法系大白猪，且两品系均有表型记录和系谱记录，系谱共由3 086头大白猪组成。分别使用系谱、SNP和ROH进行个体近交系数估计，并将近交系数作为协变量利用动物模型对总产仔数进行近交衰退评估。为了精准定位导致总产仔数衰退的基因组片段，又进一步对每条染色体以及显著染色体分段计算近交系数并估计其效应，检测是否能引起总产仔数发生近交衰退现象。对于加系群体，F_ROH、F_GRM和F_PED估计的近交系数均值分别为0.124、0.042和0.013，其中F_ROH和F_PED相关最高，相关系数为0.358；对于法系群体，F_ROH、F_GRM和F_PED均值分别为0.123、0.052和0.007，其中F_ROH和F_GRM相关最高，相关系数为0.371。利用3种不同计算方法所得近交系数用于估计近交衰退时，加系群体的总产仔数均检测到显著的近交衰退，而且当F_ROH、F_GRM和F_PED每增加10%时，总产仔数分别减少0.571、0.341和0.823头；但法系群体仅有F_ROH估计的总产仔数检测到显著近交衰退，F_ROH每增加10%时，总产仔数减少0.690头。为了锁定相关的染色体和基因组区段，首先利用ROH估计每条染色体近交系数并进行近交衰退分析发现，加系群体中检测到第6、7、8和13号染色体产生了显著近的总产仔数交衰退，而法系群体未检测到与近交衰退相关的染色体。然后，又将与加系总产仔数近交衰退显著相关的4条染色体平均分为2、4、6、8个片段进行近交衰退检测，其中平均分成8段后的染色片段的长度范围为15.1~25.8 Mb。在第6、7和8号染色体分别检测到1、2和3个与总产仔数相关的近交衰退染色体片段。这些区域注释到了CUL7、MAPK14和PPARD基因与胎盘发育相关，AREG和EREG基因与卵母细胞成熟有关。本研究利用3种近交系数计算方法对两个不同来源的大白猪总产仔数进行近交衰退评估，在加系大白猪中3种估计方法都能检测到近交衰退的现象，而法系群体中只有F_ROH才能检测到。而且通过ROH方法进一步确定了能引起加系大白猪总产仔数衰退的4条染色体和6个特定的染色体区段，还注释到了与繁殖相关的候选基因。这为揭示近交衰退的遗传机制提供了新的研究手段，也为基因组选种选配提供了参考依据。