Dose-dependent effects of resistant potato starch in the diet on intestinal skatole formation and adipose tissue accumulation in the pig

Resistant starch (RS) intake leads to a reduction of apoptosis in the pig colon and thus to a reduction of skatole in the carcass. To determine the minimal amount of RS which is required for the effect, diets with varying amounts (20, 30 and 40%) of RS were fed to barrows and gilts. Controls were fed instead with 55% pre-gelatinized starch. Skatole was determined after slaughter in distal colon content and in adipose tissue (flare fat and belly fat). Resistant starch led to a dose-dependent reduction of skatole in the gut content from 134 microg/g dry matter (controls) to 4.8 microg/g in the 40% group. Flare fat concentrations were decreased from 159 to 20 ng/g fat and belly fat concentrations from 64 to 16 ng/g fat. Strategies to improve sensorial quality by feeding RS continuously or for only 1 week prior to slaughter are discussed.     

Characterizing developmental changes in plasma and tissue skatole concentrations in the prepubescent intact male pig

The accumulation of skatole in boars to concentrations resulting in carcass taint has been associated with elevated concentrations of steroid hormones in plasma. Studying boar taint in vivo has been challenging because steroid hormones are highly variable between individual boars. However, a peak in steroid hormones occurs between 2 and 4 wk postpartum; therefore, skatole production was investigated in the prepubescent pig. Plasma concentrations of estrone sulphate, dehydroepiandrosterone sulphate, and testosterone peaked between 2 and 4 wk postpartum in intact male pigs, whereas plasma concentrations of these steroid hormones remained low or undetectable in gilts and barrows. However, plasma skatole concentration peaked in all 3 groups of animals between 2 and 3 wk postweaning. The effects of weaning time, intestinal cell turnover, and diet on tissue skatole concentrations were then investigated. Intact male piglets were weaned at 14, 21, 28, or 35 d of age. Plasma skatole concentrations were measured weekly for a period of 63 d and peaked at 17 +/- 1, 14 +/- 1, 13 +/- 1, and 10 +/- 2 d postweaning, respectively. Intestinal cell turnover, as evaluated by villous height:crypt depth ratio, was not correlated with skatole concentrations in cecal contents, suggesting that cellular debris did not constitute a gross source of tryptophan for hindgut fermentation. The inclusion of 10% chicory inulin to piglet diets suppressed the postweaning increase in plasma skatole. Cecal skatole concentrations were also 3.3-fold lower in inulin-supplemented piglets compared with controls. The rise in plasma skatole in the prepubescent intact male pig was not associated with increased steroidogenesis but is likely due to the postweaning adaptation of the intestinal flora to an abrupt dietary change.     

Effects of feeding fat-coated butyrate on mucosal morphology and function in the small intestine of the pig

As shown earlier, pig rations with high starch and purine content initiate mucosal hypertrophy by stimulating mitotic activity and DNA formation in the small intestine, whereas in the colon butyrate inhibits apoptosis and thus increases crypt depth. It was the aim of this study to combine these effects by targeting fat-coated butyrate into the small intestine where it usually does not occur, and to investigate effects on mucosal development and function. Three groups of five pigs were fed 3.6 kg/day of either a low-energy ration [deficit group, 6.6 MJ metabolizable energy (ME)/kg] or a high-energy ration (13.7 MJ ME/kg) that was supplemented with brewing yeast as a source of purines. The third ration was of high energy and contained purines and was additionally supplemented with coated butyrate (13.5 MJ ME/kg; 29 g calcium butyrate/kg). Rations were fed for 5 days. After killing, tissue samples were obtained from the proximal, medial and distal parts of jejunum for histology. Chyme samples were obtained from the ileum of all animals and used for sucrase determination. Villus size was not changed by feeding, but butyrate had an effect on plica height and area mainly in the medial jejunum. Plica area in the butyrate group (4.2 mm(2)) was significantly higher (p 相似文献   

日粮中添加丁酸钠对生长肥育猪生产性能、胃肠道结构和血清免疫指标的影响

本试验研究日粮中添加丁酸钠对生长肥育猪生产性能、腹泻率、胃肠道结构和血清免疫指标的影响,探讨丁酸钠在生长肥育猪中应用的可行性以及对抗生素的可替代性。选用体重约40kg健康的三元杂交(杜×大×长)猪120头(阉公母各半)随机分为4组:对照组(基础日粮)、丁酸钠组(基础日粮+0.1%丁酸钠)、抗生素组(基础日粮+硫酸粘杆菌素60mg/kg)和复合组(基础日粮+硫酸粘杆菌素30mg/kg+0.1%丁酸钠)。试验72d后,进行屠宰和组织学检查,结果表明:(1)丁酸钠组、抗生素组和复合组的日增重较对照组有提高的趋势(P0.05),37～70kg阶段试验组采食量较对照组有上升的趋势(P0.05),70～98kg阶段和全程试验组料肉比有下降趋势(P0.05),丁酸钠组和复合组优于抗生素组(P0.05)。(2)试验组的腹泻率均显著低于对照组(P0.05)。(3)丁酸钠组、复合组对胃重比和肠重比的影响不明显(P0.05),而肠黏膜状况、十二指肠绒毛长度、十二指肠肠腺长度与对照组比较,差异显著(P0.05),肠黏膜结构完整,十二指肠绒毛和肠腺长度增加。(4)试验组的血清IgM、IgG、IgA含量水平均显著高于对照组(P0.05)。(5)复合组日增重(P0.05)、血清中IgM、IgG、IgA的含量水平(P0.05)在3个试验组中最高,肠膜状况、十二指肠绒毛长度、十二指肠肠腺长度方面在3个试验组中最好(P0.05);腹泻率最低(P0.05)。结果提示:在日粮中添加丁酸钠能提高生长肥育猪的生产性能,降低生长肥育猪的腹泻率,改善肠道黏膜状况和提高十二指肠绒毛和肠腺的长度,提高血清免疫蛋白的含量水平;丁酸钠替代部分抗生素后联合抗生素在生长肥育猪中使用有更佳的表现。     

Effects of dietary phytol on tissue accumulation of phytanic acid and pristanic acid and on the tissue lipid profiles in mice

Recent in vitro evidence suggests that the phytol‐derived fatty acids, phytanic acid (PA) and pristanic acid (PrA), are components of animal products with the potential to cause both beneficial and harmful effects on human health. In this study, we investigated the in vivo tissue accumulation of PA and PrA and the changes in tissue lipid profiles, using mice fed a phytol‐containing diet. After 4 weeks of treatment with a diet containing 1.0% phytol, plasma, adipose tissue, liver, and brain were collected and their lipid profiles were biochemically and gas‐chromatographically determined. Dietary phytol caused PA and PrA accumulation in the adipose tissue and liver but not in the brain, and reduced plasma and liver triacylglycerol levels. Phytol intake also decreased the fatty acid concentrations in the adipose tissue, especially polyunsaturated fatty acids such as linoleic acid, but increased the concentrations of these fatty acids in the liver. However, dietary phytol had a low impact on the brain lipid profile. This study suggests that dietary phytol intake caused accumulation of PA and PrA and modified lipid profiles in the adipose tissue and liver, but that the brain is an insusceptible tissue to dietary phytol‐induced changes.     

缓释包膜丁酸钠对断奶仔猪生产性能的影响及经济效益分析

选择96头8．10±1．1kg健康的长X大二元杂交断奶仔猪,研究不同剂量（500g／t、1000g／t和1500g／t）缓释包膜丁酸钠对其生产性能的影响。结果表明：与对照组相比,在饲料中添加500g／t、1000g／t和1500g,／t缓释包膜丁酸钠后。仔猪的日增重分别增加3．23％、4．85％和7.39％（P〈0．05）;随着添加剂量的增加,日采食量呈现增加的趋势：各包膜丁酸钠组料肉比均显著低于对照组．分别降低2．86％、4．32％和6．25％（P〈0．05）;各包膜丁酸钠组之间也存在显著差异（P〈0．05）。本研究表明,缓释包膜丁酸钠对于断奶仔猪生产性能具有明显地改善作用．能较大幅度提高仔猪养殖毛利润．具有良好的应用前景。     

Predicting the consequences of social stressors on pig food intake and performance

The influence of social stressors on pig performance, although undeniable, is frequently underestimated, and in pig growth modeling is generally ignored. The aims here were to quantify the effects of the main social stressors (i.e., group size, space allowance, feeder space allowance, and mixing) on the performance of growing pigs and to incorporate these relationships into a general growth simulation model. Effects of the individual stressors were described by conceptual equations derived on biological grounds. Parameter values were estimated from experimental data, while taking steps to avoid the problems of using a strictly empirical approach. It was assumed that social stress decreases the capacity of the animal to attain its potential. This is equivalent to lowering the maximum rate of daily gain (ADGp, kg/d). Because it is generally assumed that animals eat to attain their potential, a decrease in ADGp necessarily leads to a decrease in intake. Genetic variation among genotypes in their ability to cope with social stressors was accounted for by introducing an extra genetic parameter (EX) into the model. The value of EX adjusts both the intensity of stressor at which the animal becomes effectively stressed and the extent to which stress decreases performance and increases energy expenditure at a given stressor intensity. Rather than using an empirical adjustment to predict values for the model output variables, such as intake and gain, the chosen functional forms were integrated into a general growth model as mechanistic equations. This allowed the effects of interactions that exist between social stressors and the other variables, such as the genotype, feed composition, and environment on pig intake and growth, to be explored and, at least in principle, predicted. The adapted model is able to predict the performance of pigs differing in both the potential and ability to cope with environmental stressors when raised under given dietary, physical, and social environmental conditions. The social stressor equations developed here can be incorporated into other pig growth simulation models.     

猴头菇多糖对呼肠孤病毒感染番鸭组织病变及细胞凋亡的影响

为探讨猴头菇多糖对呼肠孤病毒感染雏番鸭组织病变及细胞凋亡的影响。本实验通过建立呼肠孤病毒感染的肝脾组织病变的动物模型,应用猴头菇多糖对感染番鸭进行防治,给药组分别添加0.01%,0.02%,0.03%的猴头菇多糖,观察其对肝脾组织病变及其细胞凋亡的影响。实验结果发现给药组的番鸭发病时间延迟、死亡率下降,细胞病变坏死较少,用中剂量的猴头菇多糖的治疗呼肠孤病毒病效果最明显。实验数据还表明猴头菇多糖给药组在病毒感染的早期促进细胞凋亡,晚期抑制细胞凋亡,这可能是猴头菇多糖能对呼肠孤病毒感染产生积极影响的原因,它有助于防止病毒在细胞中的扩散甚至有利于病毒的清除。此项研究为国内首次报道。     

The effect of parenteral immunisation on antibody production in the pig colon

Local and systemic antibody production was studied in pigs to compare responses to live and killed bacterial antigen and purified protein antigen, with and without prior mucosal stimulation. Recovery from challenge with live bacteria and intramuscular injection with killed bacteria gave rise to similar high levels of serum IgG antibody, but the ratio of specific IgA to IgG in the colon was significantly higher after infection than following vaccination with killed bacteria. Vaccination with a protein antigen gave rise to serum and local antibody production. Prior feeding of the antigen had a tolerising effect on the serum antibody response, but production of IgG and IgA antibody by the colon was not suppressed.     

Skatole metabolism in the intact pre-pubescent male pig: The relationship between hepatic enzyme activity and skatole concentrations in plasma and fat

The objective of this study was to evaluate, in the pre-pubescent intact male pig, the relationship between skatole levels and the activity of hepatic cytochrome P4502E1 (CYP2E1), cytochrome P4502A (CYP2A), aldehyde oxidase (AO), and phenol sulfotransferase 1A1 (SULT1A1). The activity of these enzymes has been positively associated with skatole clearance in mature boars. Twenty-four intact male pigs were weaned at 28 days of age and slaughtered 2 weeks postweaning, at which time caecal contents, blood, fat, and liver samples were collected. Caecal contents and fat were analyzed for skatole concentrations, and plasma was analyzed for skatole and steroid hormone (testosterone (T), dehydroepiandrosterone (DHEAS), estrone sulphate (E₁S)) concentrations. CYP2A, CYP2E1, and AO, as well as SULT1A1 activities were evaluated in liver samples. Stepwise regression was utilized considering plasma or fat skatole concentration as the dependent variables and hormone concentrations and enzyme activities as independent variables. The activities of the enzymes CYP2A, CYP2E1, and AO and concentrations of the hormones T, DHEAS, or E₁S were not correlated with concentrations of skatole in plasma or fat. However, SULT1A1 activity was negatively correlated with plasma (r = − 0.70, P < 0.05) and backfat (r = − 0.41, P < 0.05) skatole concentrations. Furthermore, this correlation was improved in plasma (r = − 0.88, P < 0.05) and fat (r = − 0.63, P < 0.05) when the concentrations of skatole in caecal contents was included as an independent variable in the multiple regression analysis, demonstrating the importance of measuring skatole production in these studies. T, DHEAS, and E₁S concentrations in plasma were not correlated with the activity of any of the enzymes evaluated. This study suggests that SULT1A1 is important in the metabolism of skatole in pre-pubescent pigs and the overall metabolism of skatole in the pre-pubescent pig differs from that in the mature boar.     

β-羟基-β-甲基丁酸对肉仔鸡生长性能和屠宰性能的影响

选择240只7日龄肉仔鸡按照体重相近原则随机分为5组,每组6个重复,每个重复8只,分别饲喂添加0%、0.01%、0.055%、0.1%、0.145% β-羟基-β-甲基丁酸(HMB)的试验日粮.采用三层笼养,试验期35 d.试验结果表明:(1)不同水平HMB对肉仔鸡生产性能的总体影响不显著.7～21日龄时,与对照组相比,0.145% HMB组内仔鸡料重比降低6.06%(P＞0.05);0.1%和O.145%HMB肥组肉仔鸡死亡率低于对照组水平.22～42日龄时,0.145%HMB组肉仔鸡采食量与对照组相比降低9.94%,各处理组体增重和料重比差异不显著(P＞0.05);7～42日龄时.0.145%HMB组肉仔鸡采食量与对照组相比降低9.03%(P＜0.05),各处理问体增重和料重比无显著差异,但0.145%HMB组肉鸡料重比最小.0.1%和0.145%HMB组肉仔鸡死亡率低于对照组和其他处理组.(2)肉仔鸡的屠宰性能包括屠宰率、半净膛、全净膛率、胸肌率、腿肌率和腹脂率在各处理问无显著差异(P＞0.05),0.145%HMB组肉仔鸡腿肌率较对照组提高3.74%(P＝0.075).可见,在7～42日龄内仔鸡日粮中添加适量的HMB可显著降低肉仔鸡采食量.而体增重和饲料效率无显著变化,并有促进肉仔鸡腿部肌肉生长发育的趋势.     

Effects of phenylbutazone, indomethacin, prostaglandin E2, butyrate, and glutamine on restitution of oxidant-injured right dorsal colon of horses in vitro

OBJECTIVE: To study the effects of phenylbutazone, indomethacin, prostaglandin E2 (PGE2), glutamine, and butyrate on restitution of oxidant-injured right dorsal colon of horses in vitro. SAMPLE POPULATION: Right dorsal colon from 9 adult horses euthanatized for reasons other than gastrointestinal tract disease. PROCEDURES: Mucosal segments from the right dorsal colon were injured via exposure to HOCl and incubated in Ussing chambers in solutions containing phenylbutazone, indomethacin, indomethacin and PGE2, glutamine, and butyrate. Transepithelial resistance and mucosal permeability to mannitol were measured, and all mucosal segments were examined histologically. RESULTS: The HOCl-injured mucosa had lower resistance and higher permeability to mannitol, compared with control tissue. Histologic changes were also evident. Resistance of HOCl-injured mucosa recovered partially during the incubation period, and glutamine improved recovery. Phenylbutazone and indomethacin increased resistance, but these increases were not significant. Butyrate and PGE2 had no effects, compared with nontreated HOCl-injured tissues. Mucosal permeability to mannitol was lower in glutamine-treated tissue, compared with nontreated tissue. Histologic changes reflected the resistance and permeability changes. CONCLUSIONS AND CLINICAL RELEVANCE: According to our findings, phenylbutazone and indomethacin do not seem to interfere with restitution of oxidant-injured mucosa of equine colon in vitro, and glutamine could facilitate mucosal restitution.     

Detection of calprotectin and its correlation to the accumulation of neutrophils within equine large colon during ischaemia and reperfusion

REASON FOR PERFORMING STUDY: The cytosolic protein complex, calprotectin, is abundant in neutrophils and could be used to improve the ability to localise and assess neutrophil infiltration in the equine intestine during ischaemia and reperfusion (I/R), but further study is required. OBJECTIVES: To assess the number of calprotectin-containing cells by immunohistochemistry in correlation with direct counting and scoring of neutrophils in the equine colon during I/R. METHODS: One and 2 h ischaemia of the left dorsal colon were induced, followed by 30 min reperfusion under general anaesthesia or by 18 h reperfusion after anaesthetic recovery. Biopsies were processed for light microscopy and stained with H/E for detection of neutrophils. To identify calprotectin-containing cells, immunohistochemistry was performed on formalin-fixed tissues with the murine MAC 387 antibody and a biotin-free peroxidase staining procedure. The number of neutrophils within submucosal venules and the colonic mucosa were calculated and compared with the number of calprotectin-positive cells. RESULTS: The number of calprotectin-positive cells within submucosal venules and within the colonic mucosa correlated significantly with the accumulation of neutrophils within the corresponding tissue segments. Within the submucosal venules, both calprotectin-positive cells and H/E-stained neutrophils increased with duration of ischaemia and peaked after 30 min of reperfusion. After 18 h reperfusion the number of these cells declined within the vessels. After 2 h ischaemia, neutrophils started to migrate into the mucosa towards the epithelium, with a significant increase over time during reperfusion, and peak infiltration after 18 h reperfusion. CONCLUSIONS: Neutrophil infiltration into the colon after I/R is a time-dependent process, involving migration through the submucosa towards the epithelium.     

Culling on low milk yield and its economic consequences for the dairy herd

Voluntary culling on low milk yield and the economic returns for herds with a stable number of milk cows was investigated for spring calving dairy herds in the Republic of Ireland. The analysis was conducted at annual involuntary removal rates: 15, 20 and 25% and replacement costs as percent of beef value 94, 126, 157%. Varying cow replacement rate above involuntary removal rate by voluntary culling increased milk sold per cow in year 16 to a maximum of +5 to +10% after practicing a fixed strategy for 16 years. Greatest absolute and relative gains in yield occur from voluntary culling at the lowest involuntary replacement rate. Voluntary culling up to 3 to 8 percentage units above involuntary cow replacement rate maximizes economic returns per cow in herd when the market price for replacement heifers exceeds 150% of their beef value. Maximum voluntary culling may be practiced for prices near or below beef value.     

GH对猪脂肪组织和Leptin分泌的调节

一般认为生长激素 (Growthhormone,GH)对动物的生长的调节是通过其受体 (GH -R)介导产生胰岛素样生长因子 - 1 (Insulinlikegrowthfactor -1 ,IGF - 1 ) ,再以内分泌方式作用于靶器官。而GH对脂肪的作用似乎是直接的 ,与IGF - 1无关 ,因为GH在体内试验的结果均可在体外试验中重现 ,而经IGF - 1处理的猪胴体组成没有重现GH处理的效应 (Etherton和Bauman ,1 998;Kindt等 ,1 998)。然而有试验表明 ,GH处理使生长猪皮下脂肪组织IGF - 1基因表达显著增高 (Coleman等 ,1 994;Brameld等 ,1 996) ,去垂体大鼠经GH处理其白色脂肪组织I…     

不同锌源及水平对幼龄艾哥兔生长性能与组织锌沉积的影响简

 为了探讨不同锌源及水平对１．５月龄艾哥兔生长性能与组织锌沉积的影响,试验选用１３２只１．５月龄艾哥兔,随机分成１１组,每组４个重复,每个重复３只兔。对照组饲喂基础日粮,试验组在基础日粮的基础上分别以饲料级ＺｎＳＯ_４、Ｍｅｔ-Ｚｎ形式添加锌７０,１０５,１４０,１７５和２１０ｍｇ／ｋｇ。预试期７ｄ,正试期３０ｄ。结果表明,在日粮中添加锌能提高１．５月龄艾哥兔生长性能,蛋氨酸锌组的平均日增重极显著高于硫酸锌组（P＜０．０１）,料重比极显著低于硫酸锌组（P＜０．０１）,胴体率显著低于硫酸锌组（P＜０．０５）。两种锌源对幼兔采食量、器官指数、组织锌含量的影响差异性不显著（P＞０．０５）。日粮锌添加水平对幼兔脾脏指数的影响差异显著（P＜０．０５）,１７５和２１０ ｍｇ／ｋｇ水平饲喂兔的脾脏指数显著低于１０５和１４０ｍｇ／ｋｇ水平。日粮锌添加形式和添加水平的交互作用对幼兔脾脏指数的影响差异显著（P＜０．０５）,对其肝脏指数、肝脏锌含量、脾脏锌含量的影响差异极显著（P＜０．０１）。在日粮中添加锌能改变１．５月龄艾哥兔生长性能,蛋氨酸锌改善幼兔生长性能的效果优于硫酸锌。蛋氨酸锌降低幼兔胴体率的趋势比硫酸锌大。日粮中锌的添加水平和添加形式存在交互作用,两种锌源在机体的代谢机制不同。综合考虑,建议１．５～２．５月龄肉兔锌添加量为７０～１４０ｍｇ／ｋｇ之间。     

日粮纤维对烟台黑猪及其杂交配套系养分消化率和氮平衡的影响

为研究日粮纤维对不同品种猪养分消化率和氮平衡的影响,试验选取体重相近、健康去势的烟台黑猪、鲁农2号猪各6头,采用有重复的3×3拉丁方设计,分别为基础日粮组,10%大豆皮替代基础日粮组,10%地瓜蔓替代基础日粮组。结果表明,添加10%地瓜蔓组显著降低两个品种猪养分消化率和氮平衡(P<0.05或P<0.01),而10%大豆皮组则影响不显著(P>0.05);纤维性饲料对鲁农2号猪养分消化率和氮平衡的影响幅度大于烟台黑猪。     

超高效液相色谱-串联质谱法测定猪组织中泰拉霉素及其代谢物残留量

对猪组织中泰拉霉素及其代谢物残留量的测定方法进行了研究,基于超高效液相色谱-串联质谱建立了猪肉、肝脏、肾脏中泰拉霉素及其代谢物残留量的测定方法。试样经乙腈-0.1%甲酸水(7+3)提取,MCX柱净化,氮吹后用乙腈-0.1%甲酸水(1+9)复溶,正离子扫描,多反应监测模式下上机分析,基质外标法定量。结果表明,泰拉霉素及其代谢物在5～500μg/kg的浓度范围内呈现良好的线性关系,相关系数(R²)均>0.99;该方法的检出限为5μg/kg(猪肉:2μg/kg),定量限为10μg/kg;在不同浓度添加水平下,平均回收率为72.6%～105.8%,日内相对标准偏差为0.5%～12.1%,日间相对标准偏差为2.9%～8.1%。该方法简便、快速、灵敏度高、重现性好,适用于猪组织中泰拉霉素及其代谢物残留量的测定。