饲粮添加酶解蛋白肽对断奶仔猪生长性能、血清免疫指标和肠道菌群的影响

本试验旨在探究饲粮添加酶解蛋白肽对断奶仔猪生长性能、血清免疫指标和肠道菌群的影响,以确定断奶仔猪饲粮中酶解蛋白肽的适宜添加水平。试验选取150头21日龄体重为(7.01±0.17) kg的健康“杜×长×大”三元杂交断奶仔猪,随机分为5个组,每组5个重复,每个重复6头(公母各占1/2)。各组断奶仔猪分别饲喂在基础饲粮中添加0(对照组)、2%、4%、6%和8%酶解蛋白肽的等氮等能饲粮。试验共35 d,其中预试期7 d、正试期28 d。结果表明：1)与对照组相比,饲粮添加6%和8%酶解蛋白肽极显著提高各阶段断奶仔猪平均日采食量和平均日增重(P<0.01),极显著降低第1～14天和第1～28天腹泻率(P<0.01),显著降低第15～28天料重比(P<0.05);饲粮添加6%酶解蛋白肽极显著降低断奶仔猪第15～28天腹泻率(P<0.01),显著降低第1～14天和第1～28天料重比(P<0.05)。2)试验第14天,与对照组相比,饲粮添加2%～6%酶解蛋白肽极显著提高断奶仔猪血清免疫球蛋白G(IgG)含量(P<0.01),饲粮添加2%、4%和8%酶解蛋白肽极显著...     

L-苹果酸对断奶仔猪炎症反应和肠道健康的影响

旨在研究日粮中添加L-苹果酸对断奶仔猪肠道健康和机体炎症反应的影响。本研究选取192头健康状况良好的28日龄三元杂交(杜×长×大)断奶仔猪(初始体重(9.12±0.52)kg),随机分为4个处理,每个处理6个重复,每个重复8头猪(公母各半)。对照组饲喂玉米-豆粕型基础日粮,3个处理组分别在基础日粮中添加0.25%、0.5%和1%的L-苹果酸制品(含有20%L-苹果酸和80%载体),试验期28 d。分别在试验的第14和28天,前腔静脉采血制备血清,检测血清炎症因子水平,试验结束时屠宰测定仔猪空肠的炎症反应、抗氧化能力并观察空肠形态,分析与肠道黏膜屏障功能相关的蛋白表达水平。结果表明：1)与对照组相比,日粮添加1%L-苹果酸制品显著降低了试验第14天仔猪血浆中促炎因子肿瘤坏死因子-α(TNF-α)和白介素-6(IL-6)的水平(P<0.01),显著升高了抗炎因子白介素-10(IL-10)的水平(P<0.01);显著降低了试验第28天血浆中IL-6的水平(P<0.01),显著升高了IL-10的水平(P<0.01);这表明日粮添加1%L-苹果酸制品缓解了断奶仔猪的炎症反...     

饲粮中添加地衣芽孢杆菌和解淀粉芽孢杆菌对断奶仔猪生长性能及血液指标的影响

【目的】研究饲粮中添加地衣芽孢杆菌和解淀粉芽孢杆菌对断奶仔猪生长性能、血常规、血清生化及抗炎抗氧化指标的影响。【方法】选取108头28日龄杜长大断奶仔猪,按体重分为3组,每组6个重复,每个重复6头。对照组饲喂基础饲粮,其余两组分别在基础饲粮中添加1 g/kg地衣芽孢杆菌、1 g/kg解淀粉芽孢杆菌,试验期28 d。在试验第14和28天,空腹称重并计算采食量,每个重复选取2头仔猪,前腔静脉采血并用血细胞分析仪和试剂盒方法测定血常规及血清生化指标。【结果】各组断奶仔猪之间的平均日增重、平均日采食量、料重比均无显著性差异（P＞0.05）。与对照组相比,解淀粉芽孢杆菌组断奶仔猪的腹泻率显著降低（P＜0.05）;地衣芽孢杆菌组和解淀粉芽孢杆菌组断奶仔猪第14天血液淋巴细胞百分含量均显著升高,白细胞介素-2（IL-2）、丙二醛含量及乳酸脱氢酶、谷草转氨酶活性均显著降低（P＜0.05）;解淀粉芽孢杆菌组断奶仔猪第14天血液中碱性磷酸酶活性显著降低,血红蛋白含量显著升高,第28天血液中IL-2含量显著降低,总蛋白、球蛋白含量均显著升高（P＜0.05）。【结论】饲粮中添加地衣芽孢杆菌或解淀粉芽孢杆菌对断奶仔猪生长性能无显著影响,但能够改善仔猪血液指标,保护肝脏功能,且添加解淀粉芽孢杆菌还可以提高仔猪新陈代谢,降低仔猪腹泻率。     

Effects of dietary supplementation with epidermal growth factor on nutrient digestibility,intestinal development and expression of nutrient transporters in early‐weaned piglets

The abnormalities in intestinal morphology and digestive function during weaning are associated with the loss of milk‐borne growth factors. Epidermal growth factor (EGF) has been shown to stimulate the growth of animals. This study was to determine the effect of dietary EGF on nutrient digestibility, intestinal development and the expression of genes encoding nutrient transporters in weaned piglets. Forty‐two piglets were weaned at 21 days and assigned to one of three treatment groups: (1) basal diet (control), (2) basal diet + 200 µg/kg EGF or (3) basal diet + 400 µg/kg EGF. Each treatment consisted of 14 replicates, and seven piglets from each treatment were sampled on day 7 and 14. The EGF supplementation significantly elevated (p < 0.05) the coefficients of total tract apparent digestibility of crude protein, calcium and phosphorus, but tended to decrease sucrase activity (p < 0.10) than the control group. At day 7 post‐weaning, animals receiving EGF diets showed a tendency (p < 0.10) towards greater ileal villus height (VH), jejunal crypt depth (CD) and duodenal VH:CD when compared with the control group. Moreover, the mRNA levels of glucose transporter 2 (Slc2a2), neutral amino acid transporter (Slc6a19) and calbindin D9k (S100G) tended to be higher (p < 0.10) for EGF groups than the control group. By day 14, EGF supplementation markedly enhanced (p < 0.05) the VH, CD and VH:CD in the jejunum compared to the control group. This addition also up‐regulated (p < 0.05) the mRNA level and the protein abundance of peptide transporter 1 than the control group. These findings demonstrated that dietary EGF beneficially enhanced nutrient digestibility, improved intestinal development and increased the mRNA expression of nutrient transporters in weaned piglets.     

Benzoic acid beneficially affects growth performance of weaned pigs which was associated with changes in gut bacterial populations,morphology indices and growth factor gene expression

This study was conducted to investigate the effects of benzoic acid (BA) on growth performance, intestinal development and intestinal barrier function in weaned pigs. Ninety weaned pigs were randomly assigned to one of three treatments: a basal diet (CON), the basal diet supplemented with 2000 mg/kg benzoic acid (BA1) and 5000 mg/kg benzoic acid (BA2). At the end of days 14 and 42, six pigs per treatment were randomly selected to collect plasma and intestinal samples. Results showed that BA supplementation not only improved final body weight, daily growth and feed conversion ratio from days 15 to 42 and days 1 to 42, but also decreased the activity of plasma diamine oxidase (day 42) and the pH values of jejunal contents (day 14) (p < 0.05). Ileal Bacillus populations (day 14) were increased by BA, while Escherichia coli counts in the ileum and caecum (day 42) were decreased (p < 0.05). Higher Lactobacillus counts occurred in the ileum (day 14, 42) of BA1‐fed piglets as compared to CON and BA2‐fed piglets (p < 0.05). In addition, BA supplementation increased the ratio of villus height to crypt depth (day 14, 42) and decreased the crypt depth (day 14) (p < 0.05). Growth‐stimulating factors (insulin‐like growth factor‐1, day 42; insulin‐like growth factor‐1 receptor, day 14, 42) and tight junction protein (occludin, day 14, 42; zonula occludens‐1, day 42)‐related gene mRNA levels were upregulated in the jejunum of piglets fed BA diets (p < 0.05). In conclusion, this study provides the first evidence that BA has beneficial effects on intestinal development and intestinal barrier function of weaned pigs, which can partly explain why growth performance of pigs was improved by dietary BA supplementation.     

Effects of supplemental palygorskite instead of zinc oxide on growth performance,apparent nutrient digestibility and fecal zinc excretion in weaned piglets

The aim of this study was to determine the effects of dietary supplementation of palygorskite instead of zinc oxide (ZnO) on growth performance, apparent nutrient digestibility and zinc contents in serum and feces in weaned piglets. One hundred and sixty‐five piglets (28 days of age, 7.10 ± 0.86 kg) were allotted to five treatments on the basis of weight and sex. Each treatment included three replicates of 11 piglets. The piglets were fed the same basal diet supplemented with 0 mg/kg (control group), 1800 mg/kg, 2400 mg/kg, or 3000 mg/kg palygorskite or 2500 mg/kg ZnO for 28 days. There was no significant difference for incidence of diarrhea among the four treatments during the 0–14‐day feeding period. Compared with the control group, piglets offered diets supplemented with 1800 mg/kg palygorskite had higher (P < 0.05) average daily gain (ADG) and crude protein digestibility. Fecal digestibility of energy in 1800 mg/kg palygorskite and ZnO groups were higher (P < 0.05) than that in the control group. Both the zinc concentrations in serum and fecal zinc excretion in palygorskite groups and control group were all lower (P < 0.05) than that in the ZnO group. In conclusion, dietary supplementation with 1800 mg/kg palygorskite can improve growth performance and nutrient digestibility and can also decrease zinc excretion in feces in weaned piglets.     

复合微生态制剂对断奶仔猪生长性能、血清生化和免疫指标及粪便中挥发性脂肪酸含量的影响

本试验旨在研究复合微生态制剂对断奶仔猪生长性能、血清生化和免疫指标及粪便中挥发性脂肪酸含量的影响。采用240头(10.0±0.3)kg的断奶仔猪(公母各占1/2),随机分成4个组,每组6个重复,每个重复10头猪。Ⅰ组(对照组)饲喂基础饲粮(含1%吉他霉素和2%抗敌素),Ⅱ组、Ⅲ组和Ⅳ组分别在基础饲粮中每天每头仔猪添加50、100和150 mL复合微生态制剂。试验预试期5 d,正试期28 d。于试验第1天和第28天仔猪前腔静脉采血,检测血清生化和免疫指标,并分别收集断奶仔猪直肠内容物,检测粪便中挥发性脂肪酸的含量。结果表明:1)与对照组相比,Ⅱ组断奶仔猪平均日增重显著提高了23.53%(P0.05),料重比显著降低了15.86%(P0.05),腹泻率降低了47.16%(P0.05)。2)试验第1天,各组之间血清生化和免疫指标差异不显著(P0.05),试验组断奶仔猪粪便中挥发性脂肪酸的含量高于对照组。3)试验第28天,Ⅱ组断奶仔猪血清中碱性磷酸酶和谷草转氨酶活性高于对照组(P0.05),血清中葡萄糖、总蛋白、白蛋白和球蛋白含量高于对照组(P0.05),而血清中尿素氮的含量较对照组降低了18.27%(P0.05);与对照组相比,Ⅱ组粪便中乙酸、丙酸和丁酸含量分别增加了21.03%(P0.05)、41.08%(P0.05)和77.84%(P0.05)。由此可见,在饲粮中每天每头猪添加50 mL复合微生态制剂可提高断奶仔猪的生长性能,降低腹泻率,增强机体免疫功能并增加粪便中挥发性脂肪酸的含量。     

Dietary copper/zinc-loaded montmorillonite improved growth performance and intestinal barrier and changed gut microbiota in weaned piglets

The effects of copper/zinc-loaded montmorillonite (Cu/Zn-Mt) on growth performance, intestinal barrier and gut microbiota of weaned pigs were investigated in the present study. A total of 108 piglets (Duroc × Landrace × Yorkshire; 6.36 kg; weaned at 21 ± 1 d age) were used in this experiment. The pigs were randomly assigned to three treatments with six replicates, six pigs in each replicate. The three treatments were as follows: (1) control group: basal diet; (2) Cu/Zn-Mt group: basal diet supplemented with 39 mg/kg Cu and 75 mg/kg Zn as Cu/Zn-Mt; and (3) Cu +Zn +Mt group: basal diet supplemented with the mixture of copper sulphate, zinc sulphate and montmorillonite (equivalent to the copper and zinc in the Cu/Zn-Mt treatment). The results indicated that, compared with the pigs from control group, average daily gain and gain: feed ratio were increased and the faecal score on days 7 and 14 after weaning was decreased by supplementation of Cu/Zn-Mt; intestinal transepithelial electrical resistance (TER) and expressions of tight junction protein claudin-1 and zonula occludens-1 were increased, and intestinal permeability of fluorescein isothiocyanate-dextran 4 kDa was decreased by supplementation with Cu/Zn-Mt. According to the Illumina-based sequencing results, Cu/Zn-Mt supplementation increased the relative abundance of core bacteria (Lactococcus, Bacillus) at genus level and decreased the potentially pathogenic bacteria (Streptococcus and Pseudomonas) in colon of weaned piglets. However, the piglets fed with the mixture of copper sulphate, zinc sulphate and montmorillonite showed no effects in above parameters in comparison with the pigs from control group. In conclusion, dietary Cu/Zn-Mt could improve growth performance, decrease the diarrhoea and improve intestinal barrier and bacterial communities of weaned pigs. The results indicated that ‘loading’ of montmorillonite with Zn and Cu changed not only its chemical but also its nutritional properties.     

不同酸化剂对断奶仔猪生长、免疫性能和微生物菌群的影响

文章旨在评估日粮添加不同酸化剂对断奶仔猪生长性能、免疫性能和微生物菌群的影响.试验将384头平均初始体重为(6.16±0.23)kg的21?d断奶仔猪随机分为4组,每组6个重复,每个重复16头,各组断奶仔猪分别饲喂基础日粮、基础日粮+45?mg/kg抗菌肽、基础日粮+4?kg/T柠檬酸及基础日粮+3?kg/T复合酸化剂...     

Modulation of broilers’ caecal microflora and metabolites in response to a potential probiotic Bacillus amyloliquefaciens

Studies have found that a dietary supplement of Bacillus amyloliquefaciens improved the growth performance, increased the nutrient digestibility of hosts and modulated the intestinal microflora. A total of 360 1‐day‐old Ross broilers were randomly divided into three treatments: a control group with a basal diet, an antibiotic group with a basal diet and added colistin sulphate, and a probiotics group with a basal diet and added Bacillus amyloliquefaciens. The HiSeq high‐throughput sequencing analysis of 16S rRNA was used to investigate the differences in birds’ caecal microflora, and metabolomics was used to analyse changes in caecal metabolites. Results showed that the supplementation of Bacillus amyloliquefaciens significantly improved the BW and ADG compared with the control birds. Results of sequencing indicated that (i) 645, 670, 596 unique operational taxonomic units (OTUs) were found in birds supplemented with Bacillus amyloliquefaciens on day 7, 21 and 42, separately, (ii) due to the diversity and relative abundance of the birds’ caecal microflora, the OTUs of the caecal microflora clustered according to age and treatment, except on day 42, (iii) among the six predominate families (Ruminococcaceae, Lachnospiraceae, Enterobacteriaceae, Erysipelotrichaceae, Lactobacillaceae and Rikenellaceae), the supplementation of Bacillus amyloliquefaciens significantly increased Enterobacteriaceae on day 42, (iv) Bacillus amyloliquefaciens increased the relative abundance of Faecalibacterium and Ruminococcus on day 21, increased the Faecalibacterium and Blautia and decreased the Ruminococcus on day 42. The metabolomics of caecal metabolites showed that the dietary Bacillus amyloliquefaciens changed the caecal metabolites involved of amino acid metabolism and glyceride metabolism, and the antibiotics changed the caecal metabolites that were related to carbohydrates and amino acid metabolism on day 21.     

Dietary chenodeoxycholic acid improves growth performance and intestinal health by altering serum metabolic profiles and gut bacteria in weaned piglets

Nutritional diarrhea and subsequent performance degradation in weaned piglets are major challenges for the pig industry. Bile acids (BA) can be added to the diet as emulsifiers. This experiment was conducted to investigate the effects of chenodeoxycholic acid (CDCA), a major primary BA, on growth performance, serum metabolic profiles and gut health in weaned piglets. A total of 72 healthy weaned piglets were randomly assigned to the control (CON) and the CDCA groups, which were feed a basal diet and the basal diet supplemented with 200 mg/kg CDCA for 30 d, respectively. Our results demonstrated that CDCA significantly increased final BW and average daily gain (ADG), decreased feed-to-gain (F:G) ratio and tended to reduce diarrhea incidence. In addition, CDCA increased the villus height-to-crypt depth (V:C) ratio, elevated goblet cell numbers and the expression of tight junction proteins, suggesting the enhancement of intestinal barrier function. As an emulsifier, CDCA increased jejunal lipase activity and the mRNA expression of pancreatic lipases. CDCA supplementation also altered the serum metabolic profiles, including increasing the levels of indole 3-acetic acid, N′-formylkynurenine and theobromine that were beneficial for gut health. Moreover, the relative abundance of 2 beneficial gut bacteria, Prevotella9 and PrevotellaceaeTCG-001, were increased, whereas the relative abundance of a harmful bacteria, Dorea, was decreased in the gut of weaned piglets supplemented with CDCA. Importantly, the altered serum metabolic profiles showed a strong correlation with the changed gut bacteria. In conclusion, CDCA improved the growth performance of weaned piglets by improving intestinal morphology and barrier function, and enhancing lipid digestion, accompanied by alterations of serum metabolic profiles, and changes in relative abundance of certain gut bacteria.     

Effects of graded levels of xylo-oligosaccharides on growth performance,serum parameters,intestinal morphology,and intestinal barrier function in weaned piglets

The objective of this study was to investigate the effects of xylo-oligosaccharides (XOSs) supplementation on growth performance, serum parameters, small intestinal morphology, intestinal mucosal integrity, and immune function in weaned piglets. A total of 240 weaned piglets with an average body weight (BW) of 8.82 ± 0.05 kg (28 d of age) were assigned randomly to four dietary treatments in a 28-d trial, including a control (CON) diet and three diets with XOS supplementation at the concentration of 100 (XOS100), 500 (XOS500), and 1,000 (XOS1000) mg/kg. There were four replicates per treatment with 15 pigs per pen. From day 1 to 14, there were no differences (P > 0.05) in average daily gain (ADG), average daily feed intake, and gain to feed ratio (G:F) during the different treatments. The different doses of XOSs showed a quadratic effect on BW on day 28, ADG, and G:F on day 1 to 28 of piglets (P < 0.05). From day 15 to 28, ADG of pigs fed the XOS500 diet was higher (P < 0.05) than pigs fed the CON diet. During the overall period (day 1 to 28), pigs fed the XOS500 diet had a higher BW, ADG, and G:F than pigs fed the CON diet (P < 0.05). In addition, compared with the CON group, the XOS500 group had significantly higher serum total antioxidant capacity, total superoxide dismutase and catalase levels, and lower malondialdehyde levels on days 14 and 28 (P < 0.05). The serum immunoglobulin G (IgG) concentration in the XOS500 group was also significantly higher compared with the CON group on days 14 and 28 (P < 0.05). However, serum immunoglobulin A and immunoglobulin M were not affected by the dietary treatments. Supplementation of XOS500 to the feed significantly increased the villus height (VH) and VH to crypt depth ratio in the jejunum and ileum in comparison with the CON and XOS1000 groups. Moreover, the XOS500 group significantly elevated the expression levels of occludin and zonula occludens protein-1 in the ileum compared with the CON group. The ileal interleukin (IL)-1β, IL-8, and interferon (IFN)-γ mRNA expression levels in the XOS100 and XOS500 groups were markedly lower than in the CON group. In contrast, the ileal IL-10 mRNA expression levels were remarkably higher in the XOS500 than in the CON group. In conclusion, XOSs have a beneficial effect on growth performance by improving serum antioxidant defense system, serum IgG, small intestinal structure, and intestinal barrier function in weaned piglets.     

Effect of fermented blood cells on growth performance and intestinal characteristics of weaned piglets

The increase in feed costs has led feeder to replace protein source. Blood meal can be used in piglet diets instead of fish meal (FM). The objective of this study was to investigate the effect of fermented blood cells (FBCs) on the growth performance and intestinal health of weaned piglets. One hundred eighty 28‐day‐old piglets were assigned and were divided into 4 groups (9 L per groups and 5 pigs per litters) randomly. The piglets were fed one of four experimental diets, fish meal, blood cells (BCs), liquid‐state fermented blood cells (LFBCs) or solid‐state fermented blood cells (SFBCs) respectively. The dietary with LFBCs and SFBCs increased the average daily gain and feed intake (ADFI) and average daily gain (ADG) (p < .05). In duodenum, LFBC group increased the villous height (p < .05). The SFBC and LFBC group significantly increased the villous height (p < .05) in the jejunum. Fermented blood cells exhibit a positive regulatory function on the intestinal tract and modulate intestinal microflora. Compared with the fish meal group, the CAT, GSH‐PX and SOD activity, and MDA level was no significant differences in jejunum and plasma of weaned piglets (p > .05). LFBCs and SFBCs significantly increased the bifidobacteria and lactobacillus number in the caecum (p < .05). Dietary LFBCs increased the expression of ZO‐1 mRNA in the jejunal of weaned piglets (p < .05). In conclusion, dietary with fermented blood cells in weaned piglets had improved growth performance and intestinal health of weaned piglets.     

Immune responses of piglets to weaning stress: impacts of photoperiod

An acute stress response can be provoked by abrupt social, nutritional, and environmental changes associated with weaning, and this may disrupt homeostasis and thus compromise well-being. Manipulating environmental factors, such as photoperiod, might provide a simple way to reduce the physiological consequences that piglets experience due to weaning stress. The objective of this study was to evaluate the impacts of photoperiod manipulation across various weaning ages on leukocyte populations, lymphocyte proliferation, natural killer cytotoxicity (NK), chemotaxis, phagocytosis, and immunoglobulin G, cortisol, and BW of piglets during the nursery phase. Sixty-eight crossbred piglets were obtained from sows kept on a short-day (8 h of light/d) photoperiod from d 90 of gestation until weaning. Piglets were weaned at 14, 21, or 28 d of age and kept on a short or long (16 h of light/d) photoperiod until 10 wk of age. Piglet BW and blood samples were collected at weaning and at 6, 8, and 10 wk of age. Pigs weaned at 28 d had reduced neutrophil counts (P < 0.001), phagocytosis (P < 0.001), and lymphocyte proliferation (P < 0.05) at weaning compared with those weaned at 14 and 21 d. Pigs weaned at 21 d tended to have lower (P = 0.08) lymphocyte counts than did pigs weaned at 14 or 28 d. Pigs weaned at 14 d had reduced (P < 0.01) NK relative to those weaned at 21 or 28 d. Photoperiod also influenced pig BW and immune status. Generally, those pigs on the long-day photoperiod and weaned at 28 d were heavier (P < 0.001) than their counterparts weaned at 14 or 21 d. At 6 wk of age, NK was greater (P = 0.002) in pigs kept on a long day and weaned at 14 or 21 d than in pigs weaned at 28 d. Phagocytosis was less (P = 0.005) at 6 wk of age, but was greater at 8 wk, in piglets kept on the long day and weaned at 28 d than in long-day pigs weaned at 14 or 21 d. These results suggest that photoperiod differentially influences immune responses in piglets weaned at different ages and indicate an inverse relationship between growth and immune status. Here, weaning at 28 d and a long-day photoperiod was the treatment combination that was most physiologically beneficial to piglets, whereas a 14-d weaning and short-day photoperiod was least physiologically beneficial.     

Effect of dietary folate level on organ weight,digesta pH,short-chain fatty acid concentration,and intestinal microbiota of weaned piglets

Folate is increasingly thought to promote gastrointestinal health and regulate the diversity of gut microbiota to alleviate weaning stress in piglets. The present study was conducted to investigate the effects of folate on organ weight, digesta pH, short-chain fatty acids (SCFAs) concentration, and intestinal microbiota in weaned piglets. A total of 28 piglets (6.73 ± 0.62 kg) were allocated to four dietary treatments consisting of a control group, 3, 9, and 18 mg/kg of folate supplementation in a 14-d feeding trial. The results showed that piglets fed with 9 and 18 mg/kg of folate supplementation had greater (P < 0.05) average liver and spleen weight than the control group. Folate supplementation (9 and 18 mg/kg) can significantly increase (P < 0.05) the stomach pH and tend (P < 0.10) to decrease the cecum pH. Folate treatment (9 and 18 mg/kg) had a positive effect on the metabolism of SCFAs in piglets, in particular, compared with the control group, and the content of acetic acid (AA) and valeric acid was markedly increased (P < 0.05) in the cecum and colon, respectively. Moreover, isobutyric acid, butyric acid, and isovaleric acid were tended (P < 0.10) to increase in the colon. Cecum contents samples were used to determine bacterial community diversity by 16S rRNA gene amplicon sequencing. At the genus level, in the cecum, there was a higher (P < 0.05) relative abundance of Lactobacillus reuteri, Lactobacillus salivarius, and Lactobacillus mucosae in the 9 mg/kg folate supplementation group. The functional pathways analysis predicted that folate may modify nutrient metabolism by changing the gut microbiota function of weaned piglets. Furthermore, the data showed that Lactobacillus was positively correlated with AA in the cecum. Overall, these findings suggested that folate treatment could increase the organ weight and the stomach pH of weaned piglets and had beneficial effects on gut health, which might be attributed to the alteration in intestinal microbiota induced by folate and the interaction of the intestinal microbiota with SCFAs.     

早期断奶对仔猪肠通透性和肠上皮紧密连接蛋白Occludin mRNA 表达的影响

本文旨在研究早期断奶仔猪的肠通透性变化并探讨其机制.试验采用32头21日龄断奶仔猪,并于仔猪21、28和35日龄取样测定血浆D-乳酸含量、二胺氧化酶(DAO)活性和尿中乳果糖/甘露醇比率观察肠通透性改变,同时检测肠上皮紧密连接蛋白Occludin mRNA表达水平.结果显示:与断奶前相比,28日龄时血浆D-乳酸含量、DAO活性和乳果糖/甘露醇比差异达到显著水平(P<0.05),且至35日龄时,肠道仍然维持这种较高的通透性;仔猪断奶后Occludin mRNA相对表达量下降明显,与断奶前相比差异显著(P<0.05),35日龄时,表达量有所恢复,但仍然低于断奶前表达水平.试验结果提示,早期断奶后仔猪肠道的通透性增加,肠屏障功能破坏,可能归因于肠上皮细胞紧密连接蛋白Occludin mRNA表达下降.     

Effects of composite antimicrobial peptide on growth performance and health in weaned piglets

This study was conducted to evaluate the effects of composite antimicrobial peptide (CAP) on growth performance and health status in weaned piglets. Over 28 days, 36 weaned piglets (body weight, 10.58 ± 0.99 kg) underwent three treatments: negative control (NC, basal diet), positive control (PC, basal diet + 20 mg/kg colistin sulphate + 50 mg/kg kitasamycin), and CAP treatment (CAP, basal diet with 400 mg/kg CAP). Average daily gain of piglets fed the CAP diet was greater (P < 0.05) than that of piglets fed the PC or NC diet during days 1–7, 8–14 and 15–21. Diarrhea rates of piglets fed the CAP or PC diet were lower (P < 0.05) than those of NC‐fed piglets during days 1–7. Apparent total tract digestibility for dry matter and crude ash in CAP‐fed piglets was greater (P < 0.05) than that of NC‐fed piglets. In the CAP group, Lactobacillus and Bifidobacterium counts were greater (P < 0.05) and Escherichia coli counts were lower (P < 0.05) than numbers for the NC group. Our results indicate that dietary CAP had beneficial effects on growth performance and health status in weaned piglets.     

The influence of indigestible protein on broiler digestive tract morphology and caecal protein fermentation metabolites

Indigestible dietary protein fermentation products have been suggested to negatively influence broiler performance due to their impact on health and digestive tract morphology. This study evaluated the digestive tract morphology and caecal protein fermentation metabolites of broiler fed 3 dietary protein levels (24%, 26% and 28%) with low or high indigestible protein (LIP, HIP). Two completely randomized 3 × 2 factorial trials were conducted with protein level (PL) and indigestible protein (IDP) as the main factors. In both trials, birds received six diets (24-LIP, 24-HIP, 26-LIP, 26-HIP, 28-LIP and 28 HIP) formulated with no medication. On day 5, trial 1 birds were vaccinated with Coccivac-B52, while trial 2 received no vaccine. Tissue and caecal samples were collected and caecal contents analysed for fermentation metabolites. Differences were considered significant when p ≤ .05. The LIP treatment caecal content in trial 1 at 14 days had greater histamine, agmatine and cadaverine levels, while HIP diets resulted in increased serotonin, tryptamine and spermidine. Histamine, serotonin and tryptamine at day 28 were not affected by IDP, and ammonia was not affected by treatments at day 14 or day 28. At day 14, HIP birds had lower total short-chain fatty acids, higher caecal pH and heavier pancreas, proventriculus, gizzard, jejunum and ileum weights. The same effects of IDP found in trial 1 were observed for histamine, agmatine, cadaverine, serotonin, tryptamine and spermidine at day 21 in trial 2. Trial 2 had a PL-by-IDP interaction influencing tyramine, spermidine (28-LIP > 24-LIP) and spermine with values increasing with PL for LIP diets and remaining constant for HIP diets. An interaction between PL and IDP was found for ammonia level and was similar to interactions for biogenic amines. In conclusion, dietary PL and IDP influence broiler caecal protein fermentation metabolites and those effects varied with coccidiosis vaccination and rearing environment.     

不同形式氧化锌对断奶仔猪生长性能和肠道健康的影响

本试验旨在研究不同形式氧化锌对断奶仔猪生长性能、营养物质表观消化率、血清抗氧化能力及肠道形态的影响。采用完全随机区组试验设计,将144头健康三元(杜×长×大)杂交断奶仔猪[(6.42±0.51) kg]分为3个组,每组6个重复,每个重复8头猪。试验期28 d,分为前期(第1～14天)和后期(第15～28天)2个阶段。各组分别为：普通氧化锌组(在前期基础饲粮中添加1 600 mg/kg普通氧化锌,后期添加110 mg/kg,以锌元素计);钝化氧化锌组(在前期基础饲粮中添加1 600 mg/kg钝化氧化锌,后期添加110 mg/kg,以锌元素计);纳米氧化锌组(在前期基础饲粮中添加1 600 mg/kg纳米氧化锌,后期添加110 mg/kg,以锌元素计)。基础饲粮为玉米-豆粕型。结果表明：1)试验前期,与普通氧化锌组相比,钝化氧化锌组断奶仔猪第14天体重和平均日增重显著提高(P<0.05),料重比显著降低(P<0.05);钝化氧化锌组和纳米氧化锌组腹泻率显著降低(P<0.05)。试验全期(第1～28天),与普通氧化锌组相比,钝化氧化锌组和纳米氧化锌组断奶仔猪腹泻率显著降低...     

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。