乳酸型复合酸化剂饲喂效果试验

为了仔猪早期断奶,研制代乳品饲料,使仔猪正常生长,提高母猪生产能力成为畜牧生产中的关键。研究选用日龄(23~25日龄)、体重相近,公母对等,同批次断奶的杜长大三元杂交仔猪90头为研究对象,探讨乳酸型复合酸化剂饲喂效果。结果表明,在30 d的试验期,添加不同比例乳酸型复合酸化剂可极显著提高日增重15.31%(P<0.01)或27.25%(P<0.01);可显著提高日采食量6.65%(P<0.05)或8.27%(P<0.05);极显著降低耗料增重比9.24%(P<0.01)或15%(P<0.01),增重饲料成本显著降低7.07%(P<0.05)或极显著降低14.89%(P<0.01),在防病抗病和降低腹泻方面均有一定的效果。由研究结果来看乳酸型复合酸化剂具有推广价值。     

谷氨酰胺二肽调节断奶仔猪生长性能的研究进展

谷氨酰胺是一种条件性必需氨基酸,谷氨酰胺二肽是谷氨酰胺和其他氨基酸形成的二肽。因其不仅能发挥与谷氨酰胺类似的生物学功能,而且还克服了谷氨酰胺的缺点,近年来受到了动物营养学家的广泛关注,国内外许多研究者也开展了谷氨酰胺及其二肽在动物上的研究工作。主要就谷氨酰胺二肽的生物学功能及对断奶仔猪生长性能的影响进行了综述。     

酪蛋白酶解物对宫内生长迟缓新生仔猪小肠生长发育的影响

为探讨酪蛋白酶解物对宫内生长迟缓仔猪小肠生长发育的影响，选择胎儿在母体内发育迟缓（IUGR）初生仔猪15头，分为新生对照组（N）、酪蛋白组（C）和酪蛋白酶解物组（CH），以牛乳为基础日粮，C组用1．5％酪蛋白溶液取代10％（体积分数）的牛乳，CH组用1．5％酪蛋白酶解液取代10％（体积分数）的牛乳，人工饲喂3d后宰杀取样。结果表明：CH组仔猪小肠黏膜DNA含量及麦芽糖酶活性较N组显著提高（P〈0．05），而c组与N组相比未发生显著变化（P〉0．05）。此外，与N组仔猪相比，C组仔猪小肠各段绒毛高度都有不同程度降低（P〉0．05），而CH组仔猪小肠各段绒毛高度与N组仔猪接近，未有明显变化。提示：酪蛋白酶解物有刺激新生IUGR仔猪小肠黏膜上皮细胞的增殖和提高麦芽糖酶活性的趋势。     

谷氨酰胺对早期断奶仔猪小肠粘膜形态和抗氧化性能的影响

研究谷氨酰胺处理对断奶仔猪小肠粘膜形态变化和抗氧化作用的影响。试验选用40头(28±1)d断奶、体重均一的长白×约克夏仔猪,按单因素完全随机化设计随机分为2组,一组为对照组,喂基础日粮;一组为试验组,基础日粮添加1.2%的谷氨酰胺。在断奶后7d每个处理随机选取4头仔猪屠宰,取小肠组织,测定肠粘膜的形态变化和生化指标。结果表明:日粮中添加谷氨酰胺提高了小肠绒毛高度和固有层厚度,提高了GSH含量和CAT活性,降低了MDH含量,对肠粘膜起到了保护作用。     

血浆蛋白和肠粘膜蛋白对仔猪生长性能的影响

在哺乳仔猪和断奶仔猪的日粮中分别添加血浆蛋白粉和肠粘膜蛋白粉,研究其对仔猪生长性能的影响.结果证实,血浆蛋白和肠粘膜蛋白能提高断奶仔猪的体重和日增重,增加采食量,降低腹泻率,改善饲养效应.     

高剂量单宁酸对断奶仔猪血液学参数、脏器指数和组织病理学的影响

本试验通过研究高剂量单宁酸对断奶仔猪血液学参数、脏器指数和组织病理学的影响,来评估高剂量单宁酸用于断奶仔猪饲粮的安全性。选取21日龄左右的杜长大(DLY)断奶仔猪144头,按照性别和体重采用随机完全区组设计分为4组(每组6个重复,每个重复6头猪,公母各占1/2):对照组仔猪饲喂基础饲粮,试验组仔猪分别饲喂在基础饲粮中添加0.2%、1.0%和2.0%单宁酸(提取自五倍子,等量代替基础饲粮中的豆粕)的试验饲粮。预试期5 d,正试期28 d。结果显示:与对照组相比,1)饲粮添加1.0%和2.0%的单宁酸显著提高了血液中红细胞数量(P<0.05),对血红蛋白浓度和红细胞压积有提高趋势(0.05≤P<0.10);此外,血液中红细胞数量、血红蛋白浓度和红细胞压积与单宁酸添加剂量呈显著的线性正相关(P<0.05)。2)饲粮添加0.2%、1.0%和2.0%的单宁酸对血清中白蛋白浓度有提高的趋势(0.05≤P<0.10);血清中谷草转氨酶活性随着单宁酸添加剂量的增加而线性提高(P<0.05)。3)饲粮添加1.0%和2.0%的单宁酸显著降低了肝脏指数(P<0.05),且肝脏指数随着单宁酸添加剂量的增加而线性降低(P<0.05);饲粮添加0.2%的单宁酸对脾脏指数有降低趋势(0.05≤P<0.10);饲粮添加0.2%和1.0%的单宁酸对肾脏指数有降低趋势(0.05≤P<0.10),且肾脏指数随着单宁酸添加剂量的增加先降低后增高,有二次回归趋势(0.05≤P<0.10)。4)饲粮添加0.2%、1.0%和2.0%的单宁酸均未导致断奶仔猪的心脏、肝脏、脾脏、肺脏、肾脏、胃、十二指肠、空肠、回肠、直肠、胸腺和胰腺等组织发生病变;饲粮添加2.0%的单宁酸导致肠系膜淋巴结中局部淋巴小结生发中心扩张。由此可见,饲粮添加0.2%、1.0%和2.0%的单宁酸虽然降低了断奶仔猪的肝脏指数,但对断奶仔猪的血液学参数和组织病理学无明显的负面影响,表明饲粮中添加低于2.0%的单宁酸对断奶仔猪是相对安全的。     

Effects of rice feeding on growth performance and protein (amino acids) metabolism in weanling piglets

We investigated the effects of rice feeding on growth performance and protein (amino acids) metabolism of weanling piglets. In all, 16 weanling piglets with an average initial weight of 7.5 kg were divided into two groups. One group was fed a corn‐soybean meal‐based diet, and the other was fed a rice‐soybean meal diet, containing around 46% of corn or rice, respectively. A two‐week growth trial was conducted. The average daily gain (p = .025) and feed efficiency (p = .011) in rice‐fed piglets were significantly higher than those in corn‐fed piglets. Liver lysine‐ketoglutarate reductase activity tended to be lower (p = .073) in rice‐fed piglets than in corn‐fed piglets. Plasma urea nitrogen concentration in rice‐fed piglets was significantly lower than that in corn‐fed piglets. Plasma glucose and insulin concentrations were significantly higher in rice‐fed piglets than in corn‐fed piglets. Plasma‐free valine, isoleucine, and tryptophan concentrations were significantly higher in rice‐fed piglets than in corn‐fed piglets. In contrast, plasma histidine concentration was significantly lower in rice‐fed piglets than in corn‐fed piglets. Overall, these results show that rice feeding improves the growth performance and affects the protein (amino acids) metabolism in weanling piglets.     

Effects of crude protein and lactose levels in diets on growth performance,intestinal morphology,and expression of genes related to intestinal integrity and immune system in weaned piglets

To evaluate the effects of crude protein (CP) and lactose (LAC) for weaned piglets on performance, intestinal morphology, and expression of genes related to intestinal integrity and immune system, 144 piglets with initial weight 7.17 ± 0.97 kg were allotted in a randomized design, in a 2 × 3 factorial arrangement (20.0% and 24.0% CP and 8.0%, 12.0%, and 16.0% LAC) with eight replicates. Piglets fed 20.0% CP had greater weight gain and feed intake. Including 12.0% LAC in the 20.0% CP diet provided higher villous height in the duodenum than 8.0% LAC, and 12.0% or 16.0% LAC in the 24.0% CP diet resulted in higher villous height in the jejunum and ileum, and higher villi/crypt ratio in the ileum than 8.0% LAC. No effects of CP and LAC on interleukin‐1β and tumor necrosis factor‐α mRNA were observed. The 16.0% LAC diet provided higher gene expression of transforming‐β1 growth factor. Feeding 20.0% CP resulted in better performance than 24.0% CP. The 12.0% LAC diet promoted greater genetic expression of occludin and zonula occludens. Including 12.0% LAC in the diet may improve intestinal epithelial morphology and integrity, and these improvements are more evident when piglets are fed diets with 24.0% CP.     

香芹酚和百里香酚对断奶仔猪结肠微生物的影响研究

试验旨在研究日粮添加香芹酚和百里香酚对断奶仔猪结肠微生物群落结构和代谢通路的影响。选取28日龄、体重8.5 kg±1.0 kg断奶仔猪64头,随机分为4组,每组16个重复,每个重复1头猪。A组（对照组）饲喂基础日粮＋抗生素,B组饲喂基础日粮＋20 g/t香芹酚,C组饲喂基础日粮＋20 g/t百里香酚,D组饲喂基础日粮＋20 g/t香芹酚-百里香酚混合物（质量比2：1）。试验期30 d。基于Illumina HiSeq测序平台,利用双末端测序（Paired-End）的方法进行测序。通过对OTUs聚类,进行物种注释及丰度分析;进一步进行α多样性、β多样性分析及显著物种差异分析和功能基因预测分析。结果显示：①各试验组结肠微生物多样性均显著高于对照组（P<0.05）;②D组结肠中厚壁菌门（Firmicutes）相对丰度极显著高于对照组（P<0.01）,显著高于B和C组（P<0.05）,拟杆菌门（Bacteroidetes）相对丰度显著高于对照组和C组（P<0.05）,Epsilonbacteraeota、螺旋体门（Spirochaetes）、变形菌门（Proteobacteria）相对丰度极显著低于对照组（P<0.01）。D组结肠中弯曲杆菌属（Campylobacter）相对丰度极显著低于对照组（P<0.01）,D组理研菌科RC9肠道群（Rikenellaceae_RC9_gut_group）相对丰度显著高于B组（P<0.05）,D组罗斯氏菌属（Roseburia）相对丰度极显著高于对照组（P<0.01）,D组螺杆菌属（Helicobacter）相对丰度极显著低于对照组（P<0.01）;③D组结肠微生物脂质代谢水平极显著高于对照组（P<0.01）,结肠微生物碳水化合物代谢、其他次生代谢物的生物合成和其他氨基酸代谢水平显著高于对照组（P<0.05）,结肠微生物能量代谢水平极显著低于对照组（P<0.01）。综上,在本试验条件下,断奶仔猪日粮中添加20 g/t的香芹酚-百里香酚混合物,改善了断奶仔猪结肠微生物群落结构,结肠中有益菌的相对丰度提高,有害菌的相对丰度降低,促进了结肠微生物的代谢功能。     

Dietary dimethylglycine sodium salt supplementation improves growth performance,redox status,and skeletal muscle function of intrauterine growth-restricted weaned piglets

Few studies have focused on the role of dimethylglycine sodium (DMG-Na) salt in protecting the redox status of skeletal muscle, although it is reported to be beneficial in animal husbandry. This study investigated the beneficial effects of DMG-Na salt on the growth performance, longissimus dorsi muscle (LM) redox status, and mitochondrial function in weaning piglets that were intrauterine growth restricted (IUGR). Ten normal birth weight (NBW) newborn piglets (1.53 ± 0.04 kg) and 20 IUGR newborn piglets (0.76 ± 0.06 kg) from 10 sows were obtained. All piglets were weaned at 21 d of age and allocated to the three groups with 10 replicates per group: NBW weaned piglets fed a common basal diet (N); IUGR weaned piglets fed a common basal diet (I); IUGR weaned piglets fed a common basal diet supplemented with 0.1% DMG-Na (ID). They were slaughtered at 49 d of age to collect the serum and LM samples. Compared with the N group, the growth performance, LM structure, serum, and, within the LM, mitochondrial redox status, mitochondrial respiratory chain complex activity, energy metabolites, redox status-related, cell adhesion-related, and mitochondrial function-related gene expression, and protein expression deteriorated in group I (P < 0.05). The ID group showed improved growth performance, LM structure, serum, and, within the LM, mitochondrial redox status, mitochondrial respiratory chain complex activity, energy metabolites, redox status-related, cell adhesion-related, and mitochondrial function-related gene expression, and protein expression compared with those in the I group (P < 0.05). The above results indicated that the DMG-Na salt treatment could improve the LM redox status and mitochondrial function in IUGR weaned piglets via the nuclear factor erythroid 2-related factor 2/sirtuin 1/peroxisome proliferator-activated receptorγcoactivator-1α network, thus improving their growth performance.