Effects of in ovo injection of chrysin,quercetin and ascorbic acid on hatchability,somatic attributes,hepatic oxidative status and early post‐hatch performance of broiler chicks

An experiment was conducted to evaluate the effects of in ovo injection of chrysin, quercetin and ascorbic acid on hatchability, somatic attributes, hepatic antioxidant status and early post‐hatch growth performance of broiler chicks. Four hundred and eighty embryonated broiler breeder eggs containing live 18‐day‐old embryos were divided into six groups of 80 eggs each. One group remained intact and served as a control group (i), whereas the other five groups were injected with the prepared injection solutions as follows: (ii) 0.05 ml distilled water; (iii) 0.05 ml distilled water containing 6 mg ascorbic acid; (iv) 0.05 ml dimethyl sulfoxide (DMSO); (v) 0.05 ml DMSO containing 4.5 mg quercetin; and (vi) 0.05 ml DMSO containing 4.5 mg chrysin. The hatchability rate, hatching weight, residual yolk sac weight, yolk sac‐free body weight, liver weight, hepatic glutathione peroxidase and total superoxide dismutase activities, as well as malondialdehyde concentrations, were not affected by the injected solutions. There were no differences between chicks hatched from the control and in ovo injected eggs in weight gain, feed intake and feed conversion ratio from 0 to 11 days of age. However, the specific contrast performed between the in ovo injected groups and intact eggs revealed that in ovo injection significantly increased hatchability rate (p = .0493). This finding also implies that our injection procedure was harmless. In conclusion, the intra‐egg injection of chrysin, quercetin or ascorbic acid at the injection rates used in this study did not have a significant effect on hatchability, somatic characteristics, early growth performance and hepatic antioxidant status of broiler chicks. However, the overall hatchability was higher in the in ovo injected eggs as compared to non‐injected ones. These findings also confirmed the harmlessness of the procedure developed for in ovo injection in this study.     

Effect of gut stress induced by oxidized wheat gluten on the growth performance,gut morphology and oxidative states of broilers

This study was to investigate the effect of oxidized wheat gluten (OG) on growth performance, gut morphology and its oxidative states of broilers. One hundred and eighty‐day‐old male broilers (10 chicks/pen) were randomly allocated into three dietary treatments: control diet (CON), diet with 8% wheat gluten (WG) and diet with 8% OG with six pens/treatment. Body weight (BW) (21 and 35 days) and average daily gain (ADG) (1–21 days and 22–35 days) decreased (p < .05) and feed conversion ratio (FCR) (1–21 days and 22–35 days) increased (p < .05) in OG treatment. Feed intake (FI) decreased (p < .05) in WG and OG treatments during 22–35 days. However, FI was not influenced by dietary treatments during 1–21 days (p > .05). The OG‐fed broilers had a lower faecal pH value (p < .05) and higher faecal moisture content (p < 05) at 14, 21, 28 and 35 days. Villus height, crypt depth and V/C value were not different (p > .05) among treatments at 21 and 35 days. Lipid peroxidation (LPO) (21 and 35 days) and malondialdehyde (MDA) (35 days) content in crop of OG treatment increased (p < .05). Oxidized glutathione (GSSG) (21 days), LPO (21 and 35 days) and MDA (21 and 35 days) content in ileum of OG treatment increased (p < .05). The reduced glutathione/oxidized glutathione (GSH/GSSG) (21 days) and (GSH) (35 days) in ileum of OG treatment decreased (p < .05). The present findings indicate that OG might be a stressor for broiler gut, which could induce oxidative stress both in crop and in ileum, and the diarrhoea as well. The growth performance of broiler was consequently depressed.     

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.     

Effects of oral administration of different dosages of carvacrol essential oils on intestinal barrier function in broilers

Essential oils are widely used in the pharmaceutical, food and cosmetic industries, and many plant essential oils have shown that they have positive effects on broilers nutrition. This experiment was conducted to study the effects of orally administered different dosages of carvacrol essential oils on intestinal barrier function in broiler chickens. A total of eighty 28‐day‐old (1.28 ± 0.15 kg) ROSS 308 broilers were randomly allocated to four groups of 20 replicates each, with one chicken per replicate per cage, and all were fed with the same diet. Four experimental groups were orally administered 0, 200, 300 or 400 μl carvacrol essential oils at 18:00 hr every day during the 2‐week experimental period. As a result of which, the gene expression of the occludin, claudin‐1, claudin‐5, ZO‐1 and ZO‐2 in intestinal mucosa of small intestine (p < 0.05) and the goblet cell content in small intestine epithelium (p < 0.05) were significantly increased; test subjects with 300 or 400 μl carvacrol essential oils reduced the microbial counts of Salmonella spp. and Escherichia coli in the intestines (p < 0.05); Essential oils administration also significantly increased activity of the sucrase (p < 0.05) and lactase (p < 0.05) in intestinal mucosa. In conclusion, the carvacrol essential oils have positive effects on growth performance and intestinal barriers function of broilers; those effects may be related to the dosage, as administration of 300 or 400 μl was more effective than that of 200 μl.     

甜菜碱对热应激肉鸡生长性能、十二指肠消化酶活性及盲肠微生物区系的影响

本试验通过在饲粮中添加不同剂量的甜菜碱研究其对热应激肉鸡生长性能、十二指肠消化酶活性及盲肠微生物区系的影响。选取270只14日龄爱拔益加(AA)肉鸡随机分成6组:常温组、热应激组,常温+0.1%甜菜碱组、热应激+0.1%甜菜碱组、热应激+0.2%甜菜碱、热应激+0.4%甜菜碱组。热应激肉鸡饲养在(32±1)℃的高温环境中。每组3个重复,每个重复15只。预试期7 d,正试期21 d。结果表明:1)饲粮添加甜菜碱可极显著增加28~42日龄热应激肉鸡的体重(P<0.01),极显著降低22~35日龄肉鸡料重比(P<0.01);2)除添加0.1%和0.2%甜菜碱饲粮对28日龄热应激肉鸡胰蛋白酶活性无显著影响(P>0.05)和添加0.1%甜菜碱对35日龄热应激肉鸡淀粉酶活性无显著影响(P>0.05)外,不同浓度的甜菜碱均能显著或极显著增加28、35、42日龄热应激肉鸡十二指肠胰蛋白酶、淀粉酶和胰脂肪酶活性(P<0.05或P<0.01);3)饲粮添加甜菜碱极显著提高了28、35、42日龄热应激肉鸡盲肠内乳酸杆菌的数量(P<0.01),极显著降低了产气荚膜梭菌的数量(P<0.01)。由此可见,热应激状态下,在基础饲粮中添加甜菜碱可改善AA肉鸡生长性能,提高十二指肠消化酶的活性,维持盲肠内微生物区系平衡,从而减轻热应激对肉鸡的危害。     

新城疫含硒油佐剂疫苗增强肉鸡免疫效果的研究

以新城疫ＬａＳｏｔａ系疫苗滴鼻，采用自制的含１５×１０－６亚硒酸钠新城疫油佐剂疫苗给４０只５日龄ＡＡ肉鸡颈部皮下接种，于１５、２５、３５、４５日龄时分别抽取１０只进行称重和测定血硒含量、Ｈｌ抗体水平。结果表明，新城疫含硒油佐剂疫苗接种肉鸡的增重、血硒含量及ＨＩ抗体水平均高于非含硒新城疫油佐剂疫苗接种鸡（Ｐ＜０．０１或Ｐ＜０．０５）。     

亚硒酸钠在肉鸡体内药代动力学的研究

实验研究了30日龄肉鸡单次肌注(0.6mg/Kg)亚硒酸钠注射液后不同时间采血,用流动注射氢化物发生原子吸收光谱法测定血硒浓度,经微机处理得出血硒浓度及药动学参数,血硒浓度-时间曲线符合一级吸收一室开放模型,最佳药时方程:C=100.2001(e-0.0197t-e-1.6428t)。主要药动学参数:t1/2Ka为0.421 9h,t1/2Ke为35.121 5h,tp为3.312 4h,Cmax为93.986 5μg/L,AUC为5 025.314 9(μg/L).h。根据单剂量给药参数,计算出多剂量给药参数。     

茶多酚对高酒糟日粮肉鸡生产性能和抗氧化特性的影响

本研究旨在评估添加茶多酚对高酒糟(distillers dried grain with solubles DDGS)日粮肉鸡生产性能和抗氧化特性的影响。将400只21日龄肉鸡随机分为5个处理,每个处理4个重复,每个重复20只。正对照组为玉米-豆粕型日粮,负对照组为玉米-豆粕-DDGS型日粮(15%DDGS),处理组分别在负对照日粮中添加100、300、500 mg/kg茶多酚。结果表明,与正对照组相比,后期日粮中添加15%DDGS对肉鸡生产性能无显著影响(P>0.05),但血液的GSH-Px降低8.31%(P<0.01),胸腿肉T-AOC含量降低,腿肉MDA值显著升高(P<0.05)。添加茶多酚提高了血液的T-AOC和GSH-Px活性(P<0.05)。随着茶多酚添加剂量的升高,T-AOC和GSH-Px有升高的趋势,但各水平组之间差异不显著;茶多酚添加300 mg/kg以上能显著降低胸腿肌MDA值(P<0.05),提高T-AOC含量,改善肉质的抗氧化特性。本研究结果表明,在肉鸡高DDGS日粮中添加茶多酚可以改善肉鸡机体及肉质的抗氧化特性。     

肉鸡玉米型日粮添加高剂量植酸酶对其养分利用的影响

文章旨在研究肉鸡饲粮中植酸酶水平从1000 FTU/kg(行业推荐水平)提高到2500 FTU/kg(超剂量水平)对肉鸡养分回肠表观消化率系数和氮平衡校正表观代谢能值的影响。试验选择360只1日龄雄性肉仔鸡,随机分为3组,每组4个重复,每个重复30只肉鸡。试验1~14 d饲喂基础日粮(前期料),在15~21 d期间饲喂3种日粮,即正对照日粮(不含植酸酶)、负对照日粮(1000 FTU/kg植酸酶),植酸酶组日粮(2500 FTU/kg植酸酶)。负对照组日粮除钙和非植酸磷含量降低1.80 g/kg和1.50 g/kg外,其余营养指标均与正对照组日粮相同。结果显示,正对照组日粮的总能和粗蛋白质回肠表观消化系数显著高于负对照组(P <0.05)。正对照组日粮中淀粉、钙、磷的回肠表观消化系数与负对照组日粮无显著差异(P> 0.05)。正对照组日粮的氮校正表观代谢能显著低于负对照组日粮(13.34 MJ/kg和14.46 MJ/kg,P <0.05)。负对照组日粮中植酸酶水平从1000 FTU/kg升高至2500 FTU/kg,导致总能和粗蛋白质回肠表观消化系数分别升高2.5%和7.1%(P <0.05),且磷有显著升高的趋势(10.4%,P=0.08)。此外,负对照组日粮中植酸酶水平从1000 FTU/kg升高至2500 FTU/kg时对淀粉回肠表观消化系数和日粮的氮校正表观代谢能值无显著影响(P> 0.05)。综上所述,日粮超剂量植酸酶水平(≥2500 FTU/kg)在改善玉米能量、蛋白质和磷在回肠消化率的效率要优于肉鸡行业推荐水平。     

地塞米松和饲粮能量水平对肉仔鸡能量采食及神经肽Y基因表达的影响

本试验旨在探讨注射地塞米松(DEX)模拟应激状态下,应激和饲粮能量水平对肉仔鸡能量采食的影响。选取体重相近的180只23日龄的雄性爱拔益加(AA)肉鸡随机分成6组,每组3个重复,每个重复10只鸡。试验采用2×3析因设计,因素为DEX[处理(注射DEX2 mg/kg)、未处理(注射等剂量生理盐水)]和饲粮能量水平[高能(HE)、低能(LE)以及高能、低能自由采食(H-LE)]。预试期5 d,正试期7 d。结果表明:1)DEX处理极显著降低了肉仔鸡的采食量和体增重(P<0.01),极显著提高了耗料增重比、耗能增重比、腹脂率以及血浆葡萄糖、甘油三酯和尿酸的浓度(P<0.01),显著提高了肠道指数(P<0.05)。2)采用LE饲粮体增重(P<0.05)、腹脂率(P<0.01)显著低于其他2种饲粮,耗料增重比显著低于HE饲粮(P<0.05);采用HE饲粮耗能增重比极显著高于其他2种饲粮(P<0.01);采用H-LE饲粮神经肽Y(NPY)基因表达量显著高于LE饲粮(P<0.05)。3)DEX、饲粮能量水平对耗料增重比(P<0.05)和耗能增重比(P<0.01)的影响存在显著的互作效应。结果提示,DEX应激可使肉仔鸡血浆中葡萄糖、尿酸和甘油三酯的浓度升高;DEX应激和HE饲粮均能增加脂肪在腹部沉积,提高耗料增重比和耗能增重比;H-LE饲粮能上调肉仔鸡下丘脑NPY基因表达。