短链脂肪酸醋在仔猪日粮中的应用研究

本试验主要研究以三丁酸甘油酯为主的短链脂肪酸酯对早期断奶仔猪生长性能的影响.选用25±1日龄的大白和长白断奶仔猪72头,随机分为试验组和对照组.每组设3个重复.每个重复12头猪,试验周期为20d.试验组日粮中添加0.4%短链脂肪酸酯,对照组相应部分用0.4%的乳清粉代替.结果表明:添加0.4%短链脂肪酸酯的试验组对早期断奶仔猪的日增重有显著性影响(p<0.05).     

甜菊糖甙在断奶仔猪中的应用研究

试验选用216头21 d杜长大断奶仔猪,随机分为4组,每组3个重复,饲喂基础日粮和添加0、70、100 g/t和200 g/t甜菊糖甙的日粮,研究其对仔猪生产性能、饲料消化率和健康状况的影响。试验期为30 d。结果表明:(1)日粮中添加甜菊糖甙可显著提高断奶仔猪的日采食量、日增重和偏嗜指数(P<0.05),而各添加水平间差异不显著(P>0.05)。(2)100 g/t甜菊糖甙组仔猪腹泻指数较对照组和70 g/t组显著降低(P<0.05)。(3)100 g/t和200 g/t组能量、粗蛋白质、粗脂肪、钙和磷表观利用率较对照组有升高的趋势,但差异不显著(P>0.05)。综合考虑到生产成本,本试验条件下甜菊糖甙在断奶仔猪日粮中的适宜添加量为100 g/t。     

纳豆菌微生态制剂替代抗生素用于断奶仔猪饲料的研究

本研究以基础日粮为对照组,向断奶仔猪日粮中分别添加纳豆微生态制剂、抗生素添加剂,并对各组猪的健康、生产性能、饲料利用情况、血液生化指标、血液免疫指标、肠道主要菌群及经济效益等指标进行了全面分析。结果表明,纳豆组在抑制大肠杆菌、促进有益菌生长方面要明显好于抗生素组,其他指标无显著差异。结论认为,纳豆微生态制剂可替代抗生素用于断奶仔猪前期断奶料中。     

植物精油提取物对断奶仔猪生产性能及血液生化指标的影响

试验旨在研究植物精油提取物对断奶仔猪生产性能及血液生化指标的影响,并探讨其在断奶仔猪日粮中的适宜添加量。选用体重相近、健康的28日龄断奶杜×长×大三元杂交仔猪144头,采用单因子试验设计,随机分为4个处理,在玉米-豆粕型日粮中分别添加50、100和200g/t的植物精油提取物,对照组饲喂基础日粮,每个处理6个重复,每个重复6头猪,试验期30d。试验结果表明:日粮中添加适量植物精油提取物能提高断奶仔猪的平均日增重、平均日采食量、血清总蛋白(P0.05);降低料肉比、腹泻率和尿素氮(P0.05);谷胱甘肽过氧化物酶与超氧化物歧化酶的活力显著提高(P0.05)。研究表明,断奶仔猪日粮中添加适量的植物精油提取物(100g/t)可提高仔猪的生产性能和抗氧化能力。     

Growth in weaned piglets and levels of iodothyronines in the blood during the administration of thyroactive substances

In five trials with 100 piglets we studied the effects of thyreoglobulin, potassium nitrite and the thyreostatic preparation Carbimazol, which were added to a complete starter in the period from early weaning to the age of four weeks. Changes in the concentrations of thyroxine (T4) and triiodothyronine (T3) in the blood serum of control unmedicated piglets weaned from the sows can be characterized, after a short rise, by a decrease which stopped usually in the fourth week, accompanied by higher body weight gains. The lowest drop of T4 level was recorded in the group given potassium nitrite, with 21% methemoglobin, having the highest actual and relative weight gains. The T4 and T3 levels were not influenced by thyreoglobulin. They were decreased by Carbimazol by more than two thirds of the values which were usual at weaning if Carbimazol was administered at the highest rate of 60 mg per 1 kg of feed; neither was the growth of body weight nor feed consumption per unit of weight gain negatively influenced. An application of thyreotropic hormone on the 14th day after weaning demonstrated an inhibition of iodothyronine secretion in piglets which had been given Carbimazol, and a good response in control piglets. We drew a conclusion that the decrease in T4 and T3 levels after early weaning did not occur when iodothyronine intake with mother milk was interrupted nor was it caused by iodine deficiency, nor was it a primary cause of the reduced growth rate of piglets.     

谷氨酰胺和吉他霉素对早期断奶仔猪血细胞的影响

规模化养猪中重要的环节是仔猪早期断奶,它可同时提高母猪和仔猪的生产力。实践中,仔猪断奶时间由60日龄提前到28日龄或更短。但断奶日龄减少,仔猪应激加大,造成腹泻、水肿和内毒素休克,即“仔猪早期断奶综合征”,严重影响了养猪业的经济效益[1]。目前“早期断奶综合征”的防治常采用添加抗生素等药物手段,虽然抗生素在保证动物的健康状态,限制病原微生物的传播,保持良好的生产性能有一定作用。但使用抗生素所产生的交叉耐药性和药物残留等问题难以解决。因此,寻求一种无残留、降低应激、提高动物抵抗力和生产性能的营养素,是近些年营养学家…     

Zinc is involved in regulation of secretion from intestinal epithelium in weaned piglets

The objective was to study the effect of serosal zinc (Zn) on intestinal chloride (Cl⁻) secretion in vitro by the Ussing chamber technique. The secretagogues used to stimulate Cl⁻ secretion were serotonin (5-HT), vasoactive intestinal polypeptide (VIP) and forskolin (FSK). In addition correlations between organ and plasma Zn levels vs. the responses to 5-HT were studied. The results revealed an attenuating effect of serosal Zn on the secretory response to 5-HT, VIP and FSK. Furthermore, negative correlations between secretory responses to 5-HT vs. ADG and plasma Zn concentrations were found, whereas the responses to 5-HT did not correlate to the Zn concentration in liver or intestinal mucosa. It is suggested, that dietary Zn reduces diarrhoea directly through a regulatory role of serosal Zn on Cl⁻ secretion and indirectly by improving the nutritional status, which may stabilize the function of the intestinal epithelium.     

The pathogenesis of the post-weaning syndrome in weaned piglets: a review.

This review deals with the pathogenesis of the post-weaning syndrome. This syndrome includes post-weaning diarrhoea (PWD), oedema disease (OD) and endotoxin shock (ES). The role of different enteropathogenic Escherichia coli bacteria and some other predisposing factors relating to this post-weaning syndrome (PWS) are discussed. Based on intestinal pathophysiological mechanisms, some suggestions for the prevention of PWS and prospects for future research are given.     

早期断奶仔猪肠黏膜的营养调控

肠黏膜的发育与成熟状况是制约幼畜快速生长的关键因素。早期断奶仔猪肠黏膜免疫力较低,容易遭受饲粮抗原的刺激而引起肠黏膜过敏性损伤,诱发仔猪断奶后腹泻。通过肠黏膜营养调控技术,补充肠黏膜能量营养, 促进肠黏膜的发育与成熟,修补断奶引起的肠黏膜损伤,可以从根本上减轻仔猪断奶后腹泻的发生。本文对早期断奶引起的肠黏膜形态变化以及有利于修复受损伤肠黏膜的营养物和调控因子进行了综述。     

Host genotype and amoxicillin administration affect the incidence of diarrhoea and faecal microbiota of weaned piglets during a natural multiresistant ETEC infection

Enterotoxigenic Escherichia coli (ETEC) is the aetiological agent of postweaning diarrhoea (PWD) in piglets. The SNPs located on the Mucine 4 (MUC4) and Fucosyltransferase 1 (FUT1) genes have been associated with the susceptibility to ETEC F4 and ETEC F18, respectively. The interplay between the MUC4 and FUT1 genotypes to ETEC infection and the use of amoxicillin in modifying the intestinal microbiota during a natural infection by multiresistant ETEC strains have never been investigated. The aim of this study was to evaluate the effects of the MUC4 and FUT1 genotypes and the administration of amoxicillin through different routes on the presence of diarrhoea and the faecal microbiota composition in piglets naturally infected with ETEC. Seventy-one piglets were divided into three groups: two groups differing by amoxicillin administration routes—parenteral (P) or oral (O) and a control group without antibiotics (C). Faecal scores, body weight, presence of ETEC F4 and F18 were investigated 4 days after the arrival in the facility (T0), at the end of the amoxicillin administration (T1) and after the withdrawal period (T2). The faecal bacteria composition was assessed by sequencing the 16S rRNA gene. We described that MUC4 and FUT1 genotypes were associated with the presence of ETEC F4 and ETEC F18. The faecal microbiota was influenced by the MUC4 genotypes at T0. We found the oral administration to be associated with the presence of diarrhoea at T1 and T2. Furthermore, the exposure to amoxicillin resulted in significant alterations of the faecal microbiota. Overall, MUC4 and FUT1 were confirmed as genetic markers for the susceptibility to ETEC infections in pigs. Moreover, our data highlight that group amoxicillin treatment may produce adverse outcomes on pig health in course of multiresistant ETEC infection. Therefore, alternative control measures able to maintain a healthy faecal microbiota in weaners are recommended.     

不同药物及其组合对防治断奶仔猪腹泻效果研究

当前困惑养猪生产者最主要的问题是仔猪腹泻,因此常在仔猪日粮中添加抗生素。但大多数饲用抗生素使用中存在药物残留、耐药性等负面作用。黄霉素是欧盟批准的可以在饲料中添加的抗生素之一。但黄霉素抗菌谱窄,主要作用于革兰氏阳性菌,单独使用时控制仔猪腹泻的效果不佳,因此常采用联合用药的方式来克服这一不足。肖长艇等(1995)用黄霉素与土霉素组合用于生长猪试验证明了二者有协同作用。本试验选择黄霉素以及作用于革兰氏阴性菌的硫酸抗敌素和诺必达,单独或互相组合对断奶仔猪进行试验,观察对生长性能、粪便微生物和血液生化指标的影响。     

无抗条件下从肠道健康方面控制断奶仔猪腹泻的策略

在过去的几十年里,抗菌化合物已被用于预防亚临床和临床疾病,促进断奶仔猪生长等方面。但人们越来越关注细菌耐药性、耐药菌株及其相关基因对人类健康的潜在影响。欧盟从2006年1月1日起禁止在猪和家禽生产中使用抗生素作为生长促进剂。此外,高锌和高铜等矿物质也具有促生长作用,但饲料中添加高锌、高铜会严重污染环境。因此,在不使用抗生素的条件下,有必要制定相应的营养和饲喂策略,以便控制与断奶过渡有关的问题。本文综述改善胃肠道结构、功能,促进断奶后仔猪生长的营养策略,重点介绍益生菌、益生元、有机酸、微量元素来源及水平。     

不同蛋白水平对早期断奶仔猪生产性能、血液生化指标的影响

试验采用单因子试验设计,选用21(±2)日龄断奶、体质量约6.4kg、80头DLY杂交仔猪,随机分为5个处理,每个处理4个重复,每个重复4头猪,各处理分别饲喂粗蛋白水平为26%、23%、20%、17%、14%的等能(14448kJ/kg)等氨基酸模式(Dlys:D-SAA:DThr:DTrp=100∶57∶62∶18)的玉米-小麦-豆粕型饲粮,进行28d的试验,研究5种不同蛋白水平日粮对早期断奶仔猪生产性能、血液生化指标的影响。结果表明,随着蛋白水平的提高,ADG、ADFI、饲料转化率先增加后降低;粗蛋白水平为26%组的腹泻率、腹泻频率、腹泻指数都极显著的高于其他各组(P<0.01),其他各组之间的差异不显著;其中以第4组粗蛋白水平为23%时,仔猪的生产性能最佳。随着蛋白质水平的增加血液中的总蛋白、白蛋白含量以及白蛋白/球蛋白的值先增加后下降,粗蛋白为23%时的总蛋白、白蛋白含量最高;然而,血液中血红蛋白和尿素氮各组间差异不显著。     

马铃薯蛋白粉对断奶仔猪的应用效果研究

选择30日龄断奶体重为(6.94±0.69)kg的二元杂种商品仔猪184头,按照窝别、性别、体重相近的原则分为5组,饲喂不含马铃薯蛋白粉的基础饲粮和以2%、4%、6%的马铃薯蛋白粉及4%的血浆蛋白粉等氮替代基础饲粮中豆粕的饲粮,每组4～5个重复,每个重复8头仔猪,进行28d的饲养试验。试验第15d称重后,每个重复选择1头体重接近该圈平均体重的仔猪前腔静脉采血,测定血液生化指标;试验第15～18d,以圈为单位,收集粪样,测定蛋白质表观消化率。研究马铃薯蛋白粉在断奶仔猪上的应用效果,确定其适宜添加量。结果表明,饲粮中添加2%马铃薯蛋白粉组,与基础饲粮组相比,试验全期可以提高日增重6.14%(P>0.05)、降低料重比10%(P<0.01),降低腹泻率6.24个百分点(P>0.05),效果相当于甚至优于4%血浆蛋白粉。饲粮中添加4%和6%马铃薯蛋白粉,仔猪生长性能显著或极显著低于基础饲粮组。但6%马铃薯蛋白粉组蛋白质表观消化率高于基础饲粮组和2%马铃薯蛋白粉组(P<0.05),血浆蛋白粉组蛋白质表观消化率略高于基础饲粮组(P>0.05);2%马铃薯蛋白粉组血清总蛋白、白蛋白、球蛋白、胆碱酯酶含量最高;4%血浆蛋白粉组血清尿素氮显著低于基础饲粮组,极显著低于马铃薯蛋白粉组;6%马铃薯蛋白粉组谷丙转氨酶活性高于4%、2%马铃薯蛋白粉组(P<0.05);各个处理血液谷氨酰胺、谷氨酸含量以及谷草转氨酶活性差异不显著。由此结论,马铃薯蛋白粉在断奶仔猪饲粮中的适宜添加量为2%。     

苜蓿皂苷对断奶仔猪生产性能、消化率及血液生化指标的影响

研究了苜蓿皂苷对杜×长×大三元杂交断奶仔猪生产性能及血清生化指标的影响。根据品种、胎次、日龄、体重尽量一致的原则,选择健康无病体重9.2 kg左右的杜长大三元杂交仔猪48头(阉公猪和小母猪各半),试验采用4处理3重复单因子完全随机设计。对照组喂基础饲粮,试验组在对照组饲粮的基础上分别添加0.25％(试验Ⅰ组)、0.50％(试验Ⅱ组)和1.00％(试验Ⅲ组)的苜蓿皂苷。结果显示,1) 饲粮中添加苜蓿皂苷,提高了仔猪的日增重(0.25%的皂苷添加量效果最佳),降低了料重比(0.50%的皂苷添加量效果最佳),在一定程度上降低了仔猪的腹泻;2)苜蓿皂苷提高了粗脂肪、粗灰分和中性洗涤纤维的消化率,对粗蛋白质消化率有一定的降低作用;3)苜蓿皂苷提高了血液中红细胞和白细胞的数量,其中红细胞数量试验II组极显著(P<0.01)高于对照组,白细胞数量试验III组显著高于对照组; 4)血清中谷草转氨酶活性随皂苷添加量的增加不断提高,葡萄糖含量与之相反,但二者4个处理组之间差异均不显著(P>0.05);各试验组碱性磷酸酶均极显著(P<0.01)高于对照组,试验组尿素氮的含量均低于对照组。说明在饲粮中添加一定量的苜蓿皂苷有利于提高仔猪的生产性能,其最佳添加量在0.25%~0.50%。     

早期断奶仔猪腹泻的发生原因及其预防措施

栏舍利用率,在现代专业化、集约化养猪生产中,目前国内外已广泛实行仔猪3～4周龄断奶,即早期断奶。但早期断奶仔猪最常见、危害性最大的是断奶后腹泻。据报道,断奶后头7d腹泻率为0.6%,8～13d增到32%,14～17d增到41.4%,22～28d降到8.4%,断奶后死亡率高达20%～30%,存活下来的仔猪大多生长发育不良,总增重下降约33%,给养猪业带来了巨大的经济损失。如何降低早期断奶仔猪腹泻的发生仍是当前养猪业迫切需要解决的问题。本文就早期断奶仔猪腹泻的发生原因及其预防措施加以介绍,以供参考。1早期断奶仔猪腹泻的发生原因1.1早期断奶仔猪的消化生理特…     

EGF和IGF-Ⅰ对断奶仔猪生产性能的影响

选择21日龄断奶长白仔猪37头随机分为4组,每组3个重复,每个重复3头,分别施以表皮生长因子(EGF)、胰岛素样生长因子-Ⅰ(IGF-Ⅰ)、基础日粮、自然哺乳处理,表皮生长因子和胰岛素样生长因子-Ⅰ的剂量均为17.86μg/d。试验自断奶之日起,试验期14d。试验结果表明,第1周EGF组和IGF-Ⅰ组日增重均低于其他两组第2周EGF组日增重高于其他3组,IGF-Ⅰ组低于其他3组;整个试验期EGF组日增重高于基础日粮组,低于自然哺乳组,但差异均不显著(P>0.05)。第1周自然哺乳组的料重比均显著优于其他各组(P<0.05),第2周EGF组的料重比均显著优于其他各组(P<0.05),整个试验期EGF组和自然哺乳组的料重比接近,优于其他两组,但无显著性差异(P>0.05)。     

Morphology of the small intestine of weaned piglets and a novel method for morphometric evaluation

The intestinal morphology of 7-week-old pigs was investigated by light (LM) and scanning electron microscopy (SEM). The piglets were fed either a semisynthetic or a cereal-based diet. The shapes of the intestinal villi and crypts of the duodenum, jejunum and ileum were examined. The villi were predominantly tongue-shaped. In the duodenum they were also ridged, branched and folded, and in the jejunum they were also leaf-like and ridged. At places with lymph follicles, the surface of the ileum was rugged with meandering fold-like villi. The crypts of the three segments of the small intestine were mainly coiled and sometimes branched. A novel morphometric evaluation method was introduced using the enlargement factors of each villus and crypt surface. The enlargement factor for the villus surface of the duodenum, jejunum and ileum was 3.13, 3.72 and 2.71, respectively. The factor for the crypt surface of the duodenum, jejunum and ileum was 9.07, 8.94 and 6.53, respectively. Furthermore, the relative proliferation rate and the epithelial renewal index were calculated for the first time. The relative proliferation rate of the duodenum, jejunum and ileum was 32.88, 34.78 and 50.77 proliferations per mm crypt perimeter, respectively. The diets consumed had an influence on the epithelial renewal index being higher for piglets fed the cereal-based diets.     

Ileal digestibility of protein and amino acids from canola meal in weaned piglets and growing pigs

Two experiments were conducted to measure the apparent ileal digestibility coefficients (AID) of protein and amino acids from canola meal (CM) and a pelleted canola meal (PCM) and their effect on specific activity (SA) of pancreatic proteases in weaned piglets and growing pigs. In experiment one, 24 piglets weaned at 17 days and weighing 5.5 kg were used. Treatments were a reference diet with 200 g of crude protein (CP) kg^− 1 elaborated with casein (C) as the sole protein source, a diet containing C–CM and a diet containing C–PCM. These diets were obtained using the reference diet plus 100 g kg^− 1 of CM or PCM that substituted an isoproteic mixture of casein and maize starch from reference diet, so that the AID coefficients for their protein and amino acids could be calculated by difference. In experiment two, nine castrated pigs weighing 39.5 kg were used. Treatments were a reference diet with 160 g of CP kg^− 1 elaborated with casein (C) as the sole protein source, diet C–CM and diet C–PCM. These diets were obtained using the reference diet plus 300 g kg^− 1 of CM or PCM that substituted an isoproteic mixture of casein and maize starch from reference diet. In piglets, the AID coefficients for casein were highest (P < 0.05), those of PCM were intermediate, and those of CM were the lowest. In older pigs, the AID coefficients for casein were highest, and those of CM and PCM were similar (P > 0.05). The SAs of chymotrypsin, trypsin and carboxypeptidases A and B were lower in piglets than in heavier pigs. Moreover, the SAs of trypsin, chymotrypsin, and carboxypeptidase B were lower (P > 0.05) in animals fed casein. The results showed in piglets that whereas CM was less digestible, pelleted canola meal improved protein and amino acid ileal digestibility, resulting in similar AID coefficients to those of growing pigs.