利用近红外光谱技术快速分析全株玉米青贮营养成分

研究旨在利用近红外光谱技术(near infrared reflectance spectroscopy,NIRS)建立全株玉米青贮6种营养成分的近红外预测模型,为生产实践中合理利用全株玉米青贮饲料资源提供理论依据.选取玉米青贮样品64份作为定标集,16份作为验证集.利用NIRS结合改良偏最小二乘法(modified ...     

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.     

北京地区3种冷季型禾本科草坪草生物量及养分吸收动态的研究

以北京地区常见的3种草坪草多年生黑麦草Lolium perenne、草地早熟禾Poa pratensis和高羊茅Festuca arundinacea为研究对象,采用田间试验和实验室内分析相结合,对3种冷季型草坪草年季间生长变化规律,营养元素N、P、K养分吸收特性进行初步研究。结果表明:3种草坪草中高羊茅的年生长量最大,草地早熟禾和多年生黑麦草,二者差异不显著,但显著低于高羊茅。3种草坪草组织中N、P、K营养元素含量存在一定差异,整个生长季变化趋势相近,且变幅相对较小。N和K养分含量较高,变幅较小,P养分含量较低,变幅较大,养分含量的变化与草坪草生长变化不完全同步。而N、P、K养分每年带出量变化趋势与生长量的变化相近,即多年生黑麦草和高羊茅为"高-低-高"型,以夏季带出量较低;P养分带出量变化不大。3种草坪草地下生物量的变化趋势与地上部分生长变化趋势具有一定的相似性。高羊茅地下生物量最高,草地早熟禾次之,多年生黑麦草最少;3草种分布都是以0~10 cm层占主导地位。草地早熟禾在0~10 cm层的根系分布较多,而在10~20 cm层和20~30 cm层多年生黑麦草和高羊茅分布较多。     

施钾对草地早熟禾根部可溶性碳水化合物及叶片氮，磷和钾含量的影响

以草地早熟禾（Poapratensis）品种男爵（Baronie）为试验材料,研究了不同施钾处理对根部0～10cm可溶性碳水化合物和叶片氮,磷和钾含量的影响。结果表明：在单施钾肥的情况下,随着施钾量的增加,越冬前草地早熟禾根系可溶性碳水化合物的含量也显著提高（P〈0．05）,这可能有助于提高植株越冬率,促进返青生长,而在同时施有氮、磷的情况下,碳水化合物含量间的差异并不显著,草地早熟禾叶片氮、钾含量也随着施钾量的增加呈显著增加的趋势（P〈0．05）。通过碳水化合物及叶片氮,磷和钾含量的测定,以N5g／m^2＋P20s3．33g／m^2＋K2O 6．68g／m^2处理对草坪返青及分蘖最佳。     

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。     

日粮营养水平对西杂育成母牛日粮消化能和粪能排出量的影响

为了研究日粮营养水平(精料进食水平)对肉牛日粮消化能和粪能排出量的影响,试验选用体况良好、体重一致(347 kg±25 kg)的杂交后备母牛(西门塔尔牛(♂)×中国黄牛(♀))16头,随机分为4组,即处理Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组,每组4头,各试验组日粮精料进食量分别为1.5、2.5、3.5和4.5 kg,粗料(青贮)自由采食。总试验期为30 d,预饲期20 d后进入正试期,试验期最后7 d全收集粪样。结果表明:不同日粮处理间全消化道蛋白质、淀粉的表观消化量和日粮消化能有显著差异(P<0.05),并随日粮营养水平(精料进食水平)的增加而增加,但不同日粮处理间中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的表观可消化量没有差异,粪中能量的排出量也没有明显差异(P>0.05)。日粮可消化有机物与消化能的进食量呈直线强相关,即消化能DE(MJ/d)=0.669+18.476 DOM(kg/d)(R2=0.999 6,n=4)。     

Effect of Mediterranean saltbush (Atriplex halimus) ensilaging with two developed enzyme cocktails on feed intake,nutrient digestibility and ruminal fermentation in sheep

The aim of this study was to assess the effects of feeding Atriplex halimus (AH) silage treated with two developed enzyme cocktails to sheep on feed intake, nutrient digestibility and ruminal fermentation. The AH silage was treated without or with 2 L of ZAD1^® or ZAD2^®/1000 kg with 5% molasses and ensiled for 30 days. Barley grain (300 g/head/day) was fed as an energy supplement once daily at 10.00 hours and AH silage with or without enzyme treatment was offered ad libitum to animals twice daily at 09.00 and 16.00 hours. Sheep were fed on four experimental forage diets comprised of AH silage and barley (D1), AH silage treated with ZAD1^® and barley (D2), AH silage treated with ZAD2^® and barley (D3) and AH silage treated with a combination of ZAD1^® and ZAD2^® (1:1) and barley (D4). Ensiling AH with enzymes reduced its contents of neutral detergent fiber and acid detergent fiber. The dry matter intake of AH of D2, D3 and D4 decreased (P < 0.001) as compared to D1. However, enzyme‐treated diets had greater total digestible nutrients intake (P < 0.001) as compared to D1. The nutrients digestibility for D2, D3 and D4 were higher than those for D1 (P < 0.001), and were higher for D3 as compared to both D2 and D4. Sheep fed on D3 had highest (P < 0.001) ruminal total volatile fatty acids concentration, ammonia nitrogen concentration and microbial protein yield. It could be concluded that AH silage treated with ZAD1^® or ZAD2^® improved digestibility and rumen fermentation in sheep.     

自制中药颗粒剂对腹泻仔猪小肠黏膜病理结构及养分消化率的影响

为了研究自制中药复方颗粒剂对腹泻仔猪小肠黏膜组织结构和营养消化率的影响,试验选用人工感染大肠埃希菌引起腹泻的28日龄断奶的杜长大仔猪36头,随机均分为2组,每组3个重复,每个重复6头。抗生素治疗组在饮水中添加盐酸林可霉素2.0 m L/头饮水,2次/d,连续5 d;中药复方颗粒剂治疗组在饮水中添加2.0 g/头饮水,2次/d,连续5 d。分别于用药后14 d时,每组每个重复随机抽取1头屠宰,无菌采集小肠黏膜,通过石蜡切片和HE染色观测小肠黏膜病理组织学变化。其余仔猪继续饲养14 d,采用内源指示剂法进行消化试验。结果显示,小肠黏膜组织结构:中药复方颗粒剂治疗组小肠黏膜除有少量出血外,未发现明显病理变化。抗生素治疗组小肠黏膜脱落,有广泛充血、出血;黏膜上皮细胞变性坏死;嗜酸性粒细胞浸润,有大量以淋巴细胞杯状细胞为主的炎性细胞浸润;微绒毛排列紊乱、脱落;细胞受损严重,线粒体等细胞器结构异常。养分消化率:对于有机物质、磷的消化率,各组之间无显著差异,中药复方颗粒剂治疗组对钙的消化率为57.10%,显著高于抗生素治疗组(56.10%),并与健康仔猪组(57.40%)差异不显著。中药复方颗粒剂治疗组对粗蛋白质的消化率为79.30%,显著高于抗生素治疗组(78.50%),并与健康仔猪组(79.20%)差异不显著。中药复方颗粒剂治疗组对粗纤维的消化率为48.30%,极显著高于抗生素治疗组(46.10%),并与健康仔猪组(48.20%)差异不显著。中药复方颗粒剂治疗组对粗脂肪的消化率为63.40%,极显著高于抗生素治疗组(62.10%),并与健康仔猪组(63.60%)差异不显著。结论:抗生素治疗仔猪腹泻造成小肠黏膜明显的病理变化和功能障碍,而中药治疗有利于仔猪小肠黏膜组织结构的修复,并能显著提高小肠的养分消化率。为防治仔猪腹泻、提高仔猪的生长性能提供依据。