三价铬对肥育猪生长激素分泌及垂体mRNA表达的影响

将96头体质量约65 kg的杜长大三元杂交猪,按体质量相近、公母各半的原则随机分成4组,每组3个重复.试验猪1组设为对照,饲喂基础饲粮,其余3组为试验组,分别饲喂在基础饲粮基础上添加来源于氯化铬、吡啶羧酸铬,纳米铬的含200 μg/kg铬试验饲粮.试验猪充分饲喂,自由饮水,试验为期40 d.饲养试验结束前1 d,从每组中选择6头猪,间隔15 min颈静脉采血1次,连续3 h,制备血清用于生长激素动态分泌模式研究.饲养试验结束后,按体质量相近原则从每组中选择8头猪进行屠宰,测定背膘厚和背最长肌面积;并各采取3头猪的脑垂体,RT-PCR法测定生长激素mRNA水平.结果表明,饲粮中添加200μg/kg三价纳米铬使肥育猪日增重提高了6.31%(P<0.05),料重比降低了4.61%(P<0.05),背膘厚降低了24.32%(P<0.05),背最长肌面积提高了20.22%(P<0.05).生长激素动态模式分析结果显示,纳米铬组试验猪生长激素总体水平、最低值、峰值和峰持续时间分别提高了42.62%(P<0.05)、87.94%(P<0.05)、26.60%(P<0.05)和17.19%(P<0.05),吡啶羧酸铬组试验猪生长激素总体水平、峰值分别提高了36.58%(P<0.05)和27.18%(P<0.05).垂体生长激素基因RT-PCR分析结果显示,纳米铬组试验猪垂体生长激素mRNA水平提高了27.63%(P<0.05).研究结果提示,三价纳米铬可提高肥育猪垂体生长激素mRNA水平,促进机体生长激素分泌,从而促进生长和改善胴体特性.     

N—甲基—D，L—天冬氨酸（NMA）对育肥猪生长激素基因表达的影响

以肥育猪为对象，探讨了日粮中添加50mg/kgN－甲基－D，L－天冬氨酸（NMA）对其生长激素（GH）基因表达的影响。结果表明，添加NMA后，肥育猪日增重提高了9．31％（P＜0．01）；料重比降低了7．16％（P＜0．02）；血清GH含量提高了92．54％（P＜0．01）；垂体GH－mRNA水平提高了153．03％（P＜0．01）；下丘脑cAMP水平降低了21．89％（P＜0．01）；腺垂体中cAMP水平升高88．57％（P＜0．05）。     

Effect of chromium nanocomposite supplementation on growth hormone pulsatile secretion and mRNA expression in finishing pigs

The study was conducted to investigate the effect of chromium nanocomposite (CrNano) on growth hormone (GH) pulsatile secretion and pituitary GH mRNA expression in finishing pigs. Fifty‐four crossbred pigs (65.57 ± 1.05 kg initial weight) were randomly allotted to one of the three treatments, with three replicate pens per treatment and six pigs per pen. Pigs were offered one of the four diets including a control diet or a control diet supplemented with 200 μg/kg chromium from either chromium chloride (CrCl₃) or CrNano for 35 days. During the trial, all pigs were given free access to feed and water. After completion of the feeding trial, blood samples were taken via auriculares at 15 min intervals for 3 h and three pigs from each treatment were slaughtered to collect pituitary to determine GH mRNA level. The results of GH dynamic secretion showed that supplemental CrNano increased the mean level, the lowest value, peak value and peak duration of GH significantly, while there was no significant effect on peak amplitude. Pituitary mRNA expression of GH was improved significantly in pigs fed diet containing Cr from CrNano. These results indicated that CrNano increased GH mRNA expression and secretion in finishing pigs.     

二丁酰环腺苷酸制剂对猪生长及胴体组成的调控

通过皮下注射和饲料添加不同剂量dbcAMP制剂进行饲养试验,研究其对猪生长和胴体组成的调控效果。结果表明:皮下注射1.0mg/kg和饲料添加20mg/kg为最佳调控剂量,在生长猪阶段,日增重分别提高13.61%和15.41%(P<0.05);料重比分别降低18.81%和19.10%(P<0.05);在肥育猪阶段日增重和料重比差异不显著(P>0.05)。dbcAMP可提高猪血液T3、GH、IGF-I和cAMP的浓度(P<0.05),使血脂、TG、HDL和VLDL含量以及TP、ALB和GLOB含量增加(P<0.05),脂肪酶、ALT、AST和ALP活性提高(P<0.05)。证明dbcAMP制剂明显提高猪的生长性能,改善胴体组成。     

Changes in hormones, growth factor and lipid metabolism in finishing pigs fed betaine

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.     

包膜半胱胺对肥育猪生长性能、免疫功能、抗氧化能力及肠内容物消化酶活性的影响

本试验旨在研究日粮中添加不同水平包膜半胱胺(CCS)对肥育猪生长性能、免疫和抗氧化能力及十二指肠消化酶活性的影响。选择体重(62.12±1.43)kg的健康杜×长×大肥育猪160头,随机分为4个处理,每个处理组4个重复,每个重复10头(公、母各半)。对照组饲喂基础日粮,试验组在基础日粮的基础上分别添加100、200、400 mg/kg CCS。试验猪自由采食饮水,预试期5 d,正试期40 d。结果表明:CCS对肥育猪的平均日增重(ADG)、平均日采食量(ADFI)和耗料增重比(F/G)无显著影响,但100 mg/kg CCS组生长性能指标相对最佳;100、200 mg/kg CCS组血清IgM和补体C3水平均上升(P<0.05),C3水平随着CCS添加剂量的提高呈线性上升(P<0.05);CCS有提高血清Ig G水平的趋势(P=0.07),并呈二次升高(P<0.05);CCS提高了血清中总抗氧化能力(T-AOC)并呈二次变化(P<0.05);血清谷胱甘肽过氧化物酶(GSH-Px)水平和过氧化氢酶(CAT)活性随着CCS水平的提高呈线性及二次变化(P<0.05);肝脏GSH-Px和总超氧化物歧化酶(T-SOD)活性随着CCS水平的提高呈线性及二次增高(P<0.05);CCS提高了十二指肠总蛋白酶和总脂肪酶活性(P<0.05),使总淀粉酶活性呈二次上升(P<0.05)。可见,日粮中添加低剂量的CCS对肥育猪生产性能有一定改善趋势,CCS可提高肥育猪的免疫和抗氧化性能,促进肠道消化酶的分泌。在本试验中,CCS在肥育猪饲粮中的适宜添加水平为100 mg/kg。     

Effects of corn dried distiller's grains with solubles and enzyme premix supplements on growth performance,carcass characteristics and meat quality parameters in finishing pigs

The objective of the present study was to investigate the effects of corn dried distiller's grains with solubles (DDGS) and enzyme premix (mannanase + phytase) supplementation on the growth performance, carcass and meat quality parameters in finishing pigs. Sixty hybrid pigs (L × LW × D) with initial weight of 63.92 ± 1.50 kg were used in a 3 × 2 factorial design with main effects of DDGS levels (0, 10 and 20%) and enzyme premix levels (0% vs. 0.14%). Average daily gain (ADG, P < 0.01) and average daily feed intake (ADFI, P < 0.05) were decreased due to an increased level of DDGS additive while the feed conversion ratio was improved (P < 0.05) by adding enzyme premix. The diet cost/gain (won/kg) was saved (P < 0.01) due to an increased level of DDGS additive. There were no significant differences in carcass characteristics and meat quality parameters of Longissimus dorsi muscle by DDGS level and enzyme premix. Palmitoleic acid, oleic acid and monounsaturated fatty acid (MUFA) decreased (P < 0.05) according to DDGS level. The results indicate that DDGS may be used in feeds for finishing pig as a replacement of corn and soybean meal without affecting their carcass characteristics and meat quality.     

饲粮异亮氨酸水平对肥育猪生长性能、胴体性状和肉品质的影响

本试验旨在研究饲粮异亮氨酸水平对肥育猪生长性能、胴体性状和肉品质的影响。选取体重为(77.0±0.1)kg的杜×长×大三元杂交去势公猪72头,随机分为3组,每组6个重复,每个重复4头猪。3组试验猪分别饲喂含0.25%(低异亮氨酸水平,表现为异亮氨酸缺乏,L-Ile组)、0.39%(NRC推荐异亮氨酸水平,N-Ile组,作为对照组)和0.53%(高异亮氨酸水平,表现为异亮氨酸超量添加,H-Ile组)标准回肠可消化异亮氨酸的饲粮。试验期为28 d。结果表明:饲粮异亮氨酸水平对肥育猪的平均日增重和平均日采食量没有显著影响(P0.05),但L-Ile组料重比较对照组显著增加(P0.05);随着饲粮异亮氨酸水平的增加,肥育猪背最长肌肌内脂肪含量线性提高(P0.05),而剪切力线性下降(P0.05);与对照组相比,采食异亮氨酸缺乏饲粮的肥育猪的背膘厚、眼肌面积和肉色评分显著降低(P0.05),采食异亮氨酸缺乏或超量添加饲粮的肥育猪的热胴体重、屠宰率以及背最长肌滴水损失和黄度值均显著降低(P0.05);随着饲粮异亮氨酸水平的增加,血清甘油三酯含量线性提高(P0.05),血清尿素氮含量线性下降(P0.05);与对照组相比,采食异亮氨酸超量添加饲粮的肥育猪的血清葡萄糖含量显著增加(P0.05),采食异亮氨酸缺乏饲粮的肥育猪的血清中游离的必需氨基酸、非必需氨基酸和总氨基酸的浓度显著降低(P0.05),而采食异亮氨酸缺乏或超量添加饲粮的肥育猪血清总胆固醇、低密度脂蛋白和高密度脂蛋白含量均显著降低(P0.05)。由此得出,饲粮中异亮氨酸缺乏对肥育猪生长性能、胴体性状和肌内脂肪含量有负面影响,而超量添加异亮氨酸会显著改善肌肉的剪切力和滴水损失,增加肌内脂肪含量,但会以降低热胴体重、屠宰率为代价。     

Dietary stimulation of the endogenous somatotropic axis in weaner and growerfinisher pigs using medium chain triglycerides and cysteamine hydrochloride

Background: Three experiments were conducted to examine the overall hypothesis that addition of medium chain triglycerides(MCT) and cysteamine hydrochloride(CSH) into the diets of young and growing pigs would stimulate the endogenous somatotropic axis to improve growth and performance.Results: In Experiment 1, weaner pigs were given either a 5 d dietary supplement of 5 % MCT(n = 8) or a control diet(n = 8). MCT increased the plasma concentration of growth hormone(GH; P 0.05) and the GH secretagogue,ghrelin(P 0.05). Additionally, the MCT treatment reduced scouring(P 0.05), maintained villous height in the small intestine(P 0.05) and stabilised daily weight gain(P 0.05), compared to the controls. Experiment 2compared the effects of 4 levels(0, 1, 3 and 6 % v/v) of MCT supplementation in grower-finisher male pigs, of approximately 35 kg live weight(n = 15 per treatment). Blood samples taken after 7 wk of treatment showed that the MCT supplementation increased circulating ghrelin(P 0.001), GH(P 0.01) and insulin(P 0.05)concentrations in a dose-dependent manner. Daily weight gain, feed intake and feed conversion ratio were not affected by the MCT diets. In Experiment 3, 64 female pigs of approximately 60 kg live weight were allocated to one of three dietary treatments: control(n = 20); 6 % MCT(n = 21); and 70 mg/kg CSH(n = 21). After 3 wk of supplementation, the MCT treated pigs had a higher plasma concentration of ghrelin compared to the control and CSH pigs(P 0.05). Plasma concentrations of GH and weight were not affected by any of the dietary treatments.Conclusions: Evidence is provided in Experiment 1 to support the use of dietary MCT supplements, perhaps acting via stimulation of somatotropic endocrine pathways, to minimise weaning-associated disorders such as slowing of growth and diarrhoea. In Experiments 2 and 3, although there was no effect on weight gain or feed conversion ratio in either experiment, MCT and CSH increased endocrine components of the somatotropic axis.     

不同硒水平对山羊生长性能和血液理化指标的影响

研究在基础日粮中添加不同水平亚硒酸钠对山羊生长发育、血液理化指标及抗氧化的影响。结果表明:在基础日粮中分别添加0.1、0.3mg/kg和0.5mg/kg亚硒酸钠组与基础日粮组相比,羔羊的平均日增重显著增加(P<0.05),以0.3mg/kg亚硒酸钠组增加幅度最大,增加了42.20%(P<0.05);饲料转化率分别提高了18.51%(P>0.05)、40.74%(P<0.05)和29.63%(P<0.05);0.3mg/kg亚硒酸钠组血液中WBC、RBC和血清中TP、ALB、GLO含量显著提高(P<0.05),血清尿素氮的水平显著降低(P<0.05),血清SOD和GSH-Px活性显著升高(P<0.01),血清MDA含量显著降低(P<0.01)。因此,添加亚硒酸钠促进蛋白质合成,改善机体抗氧化功能,促进羔羊生长发育,且以在基础日粮中添加0.3mg/kg最佳。     

甜菜碱对生长肥育猪生长性能的影响及其转甲基效应研究

以添加 1 0 0 0和 1 50 0mg/kg甜菜碱的饲粮分别饲喂生长肥育猪 ,均显著提高生长肥育猪日增重 ,其中以 1 0 0 0mg/kg组效果更为明显 ,生长期提高了 1 3.2 0 % (P <0 .0 1 ) ,肥育期提高了 5.68% (P <0 .0 5)。甜菜碱增加了猪肝脏甜菜碱高半胱氨酸甲基转移酶 (BHMT)活力 ,生长期总活力与比活力 1 50 0mg/kg组分别提高了 2 3.0 8% (P <0 .0 1 )和 1 8.1 8% (P <0 .0 5) ,肥育期则以 1 0 0 0mg/kg组更为明显 ,总活力与比活力分别提高 1 6.33% (P <0 .0 5)和 1 5.63% (P <0 .0 5)。肉碱含量分析表明 ,甜菜碱均显著提高了生长猪肝脏和肌肉游离肉碱的含量 ,而肥育期仅以肝脏游离肉碱及肌肉酸不溶肉碱含量上升显著     

饲粮中添加甜菜碱对断奶仔猪生长性能和血清生化指标的影响

本试验旨在研究饲粮中添加甜菜碱对断奶仔猪生长性能和血清生化指标的影响.选用体重(7.12±0.11)kg断奶后1周的“杜×长×大”仔猪160头,随机分为4组,每组4个重复,每个重复10头.对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮上添加600、900、1 200 mg/kg甜菜碱的试验饲粮.试验期28 d.结果表明,饲粮中添加甜菜碱能够显著提高仔猪的平均日采食量和平均日增重(P＜0.05),显著增加血清生长激素和胰岛素样生长因子Ⅰ的含量(P＜0.05).600mg/kg甜菜碱显著降低了血清尿素氮和低密度脂蛋白含量(P＜0.05).但饲粮中添加甜菜碱对血清中总蛋白、白蛋白、甘油三酯、胆固醇、高密度脂蛋白含量和代谢酶的活性无显著影响(P＞0.05).由此可见,饲粮中添加甜菜碱可以提高断奶仔猪的生长性能,促进蛋白质的沉积和脂肪代谢,其中以添加量600 mg/kg效果最好.     

不同梯度发酵豆粕对育肥猪生长性能、胴体性状及肉品质的影响

试验旨在研究不同梯度发酵豆粕等量替代普通豆粕对育肥猪生长性能、胴体性状及肉品质的影响.采用单因素完全随机试验设计,选择240头初始体重(61.25±2.31) kg的"杜×长×大"育肥猪,随机分为6组,每组8个重复,每个重复5头猪.对照组育肥猪饲喂玉米-豆粕型基础日粮,5个试验组依次采用5％、7％、9％、11％、13％...     

Effects of different levels of dietary protein with or without plant extract YGF251 on growth performance,nutrient digestibility,blood profiles,fecal microbial shedding,and fecal gas emission in growing pigs

This experiment was conducted to evaluate the effects of plant extract YGF251 supplementation in different protein level diets on growth performance, nutrient digestibility, blood profiles, fecal microbial shedding, and fecal gas emission in growing pigs. A total of 144 pigs (24.72 ± 1.54 kg) were randomly assigned to the treatments in a 2 × 3 factorial arrangement of dietary protein levels (15.50%, 14.00% or 12.50%) and plant extract YGF251 levels (0 or 0.05%) with 6 replications per treatment and 4 pigs per pen. Pigs fed low protein diets had reduced average daily gain (p < 0.05) and increased feed conversion ratio (p < 0.01) compared with pigs fed high protein diets. The apparent total tract digestibility of nitrogen was decreased (p < 0.05) when reducing dietary protein level. Fecal ammonia and hydrogen sulfide emissions were reduced (p < 0.05) when reducing dietary protein level. In conclusion, the results of the current study indicated that reducing dietary protein level impaired growth performance and nitrogen digestibility but reduced ammonia and hydrogen sulfide emissions in growing pigs. Dietary supplementation with 0.05% herbal extract YGF251 was not effective in improving growth performance, nutrient digestibility, or in decreasing gas emission in different protein diets.     

亚麻籽对生长育肥猪抗氧化性能及肉品质的影响

文章旨在评估日粮添加不同水平的亚麻籽对生长育肥猪生长指标、血清和肌肉抗氧化指标及肉品质的影响.试验将576头体重接近的16周龄生长猪分为3组,每组8个重复,每个重复24头.试验育肥猪在26周龄出栏,整个试验期间3组分别饲喂亚麻籽添加水平为0、1％和2％的配合饲料.结果:1％和2％亚麻籽组育肥猪生长前期(16～20周)的...     

木棉籽油对育肥猪生长性能、胴体性状、肉品质及经济优势的影响

文章旨在评估木棉籽油替代大豆油对育肥猪生长性能、胴体性状和肉品质的影响.试验将500头20?w平均体重为(84.40±0.18)kg的育肥猪随机分为2组,每组5个重复,每个重复50头.对照组饲喂含有1.5％大豆油的基础日粮,处理组饲喂含有0.8％木棉籽油的基础日粮,试验分为0～3?w和4～6?w共42?d.结果:对照组...     

饲用枯草芽孢杆菌对育肥猪生长性能、养分消化、粪便特征及经济效益的影响

文章旨在评估日粮添加不同水平的饲用枯草芽孢杆菌对9～24周龄育肥猪生长性能、养分表观消化及粪便特征的影响。将600头9周龄平均初始体重为（22.96±0.09）kg的商品猪随机分为3组,每组5个重复,每个重复40头。对照组饲喂基础日粮,T1和T2组肥猪分别饲喂基础日粮+100和200?mg/kg枯草芽孢杆菌（3×108?CFU/kg）,试验共进行15周。结果：与对照组相比,T2组15?w育肥猪体重显著提高4.37%（P＜0.05）,同时T1和T2组1～15?w育肥猪的平均日增重较对照组分别显著提高3.81%和5.35%（P＜0.05）,饲料报酬分别显著提高4.44%和4.44%（P＜0.05）。T1和T2组育肥猪干物质表观消化率分别较对照组显著提高8.75%和9.37%（P＜0.05）,同时T1组育肥猪有机物表观消化率较对照组显著提高了6.13%（P＜0.05）。日粮添加100和200?mg/kg枯草芽孢杆菌可以显著降低6和15?w育肥猪粪便中氨气浓度和大肠杆菌数量（P＜0.05）,同时T1和T2组15?w育肥猪粪便中乳酸杆菌数量也显著高于对照组（P＜0.05）。结论：日粮添加100～200?mg/kg饲用枯草芽孢杆菌（3×108?CFU/kg）可改善9～24周龄育肥猪的饲料报酬,改善干物质表观消化率,降低粪中氨气浓度和大肠杆菌数量。 [关键词]育肥猪|枯草芽孢杆菌|生长性能|养分消化|粪便特征     

乳酸片球菌对肥育猪生长性能及肠道抗氧化能力、形态结构和菌群的影响

本试验旨在研究乳酸片球菌对肥育猪生长性能及肠道抗氧化能力、形态结构和菌群的影响。选取48头体重为(62.46±1.20)kg的"杜×长×大"肥育猪,将其随机分为2组,每组4个重复,每个重复6头猪(公母各占1/2)。对照组饲喂基础饲粮,试验组饲喂基础饲粮中添加0.1 g/kg乳酸片球菌制剂(1.0×10~(10)CFU/g)的试验饲粮。试验期56 d。结果表明,与对照组相比:1)饲粮添加乳酸片球菌对肥育猪平均日采食量、平均日增重、料重比无显著影响(P0.05)。2)饲粮添加乳酸片球菌显著提高了肥育猪十二指肠谷胱甘肽过氧化物酶(GSH-Px)活性、空肠总抗氧化能力(T-AOC)和总超氧化物歧化酶(T-SOD)活性以及回肠过氧化氢酶(CAT)活性(P0.05)。3)饲粮添加乳酸片球菌显著降低了肥育猪十二指肠隐窝深度(P0.05),显著提高了黏膜厚度(P0.05)、肠壁厚度(P0.05)以及绒毛高度/隐窝深度(P0.05);显著降低了空肠隐窝深度(P0.05),显著增加了绒毛高度/隐窝深度(P0.05);显著增加了回肠绒毛高度(P0.05)。4)饲粮添加乳酸片球菌显著增加了肥育猪空肠乳酸菌数量、定植抗力(P0.05),显著降低了大肠杆菌数量(P0.05)。由此可见,饲粮添加0.1 g/kg乳酸片球菌(1.0×10~(10)CFU/g)能改善肥育猪肠道菌群和肠道形态结构,增强肠道抗氧化能力,进而促进肥育猪的肠道健康。     

半胱胺对生长肥育猪后期生长性能的影响

选用60头体重约60kg左右的三元杂交(杜×长×大)商品代瘦肉型肥育猪,随机分为试验组和对照组两组,每组又设三个重复,每个重复10头猪。试验组饲喂添加200g/吨半胱胺含量为50%的“大丰收”(由杭州某饲料有限公司提供)的日粮,对照组日粮不添加大丰收。进行为期41天的对比试验。试验结果显示:同对照组相比试验组平均日增重、饲料转化效率、瘦肉率和胴体品质均得到不同程度的提高和改善;而且在外观上也得到明显的改善;猪后臀丰满、皮红毛亮、肌肉发达。     

不同形态的铜对猪生长性能及血清GH、血浆NPY水平的影响

将75头体质量约20kg的“军牧1号”白猪，分成A、B、C、D、E组。A组为对照组，饲以基础日粮，B、C2组分别饲以添加122．5、250mg／kg铜(硫酸铜)的日粮；D、E2组分别饲以添加122．5、250mg／kg蛋氨酸铜的日粮，观测不同形态的铜对仔猪生长性能以及血液GH、血浆NPY水平的影响。结果显示：日粮中添加2种铜均能促进仔猪的生长，提高饲料利用率，升高血液中GH和血浆NPY水平，但对采食量没有显著影响，2种铜源在相同浓度下对猪的促生长性能无差异。