【Objective】The purpose of this experiment was to explore the effects of different proportions of mixed silage of raw potato chips processing by product with rice straw（hereinafter referred to as “mixed storage”） instead of whole plant corn silage（hereinafter referred to as “silage”） on fattening performance, nutrient apparent digestibility, rumen fermentation parameters, blood biochemical indexes and economic benefits of Holstein bulls, so as to provide a theoretical basis for the use of potato processing by-products in cattle production.【Method】Sixty healthy Holstein bulls with similar body weight（（461.33 ± 33.47） kg） were randomly divided into four groups with 15 replicates in each group and one bull per replicate, including T20 group（concentrate +20% mixed silage + 80% silage）, T40 group（concentrate + 40% mixed silage + 60% silage）, T60 group（concentrate + 60% mixed silage + 40% silage）, and T80 group（concentrate + 80% mixed silage + 20% silage）. The ratio of concentrate to roughage and the composition of concentrate were the same in the experimental group. Adaptation and experimental periods lasted for 10 and 150 d,respectively.【Result】（1） there was no significant difference in average daily gain（ADG） of Holstein bulls with different proportions of mixed silage instead of whole plant maize silage（P＞0.05）. The dry matter intake（DMI） of T20 group was 4.30% higher than that of T40 group（P＜0.01）, 5.24% higher than that of T60 group（P＜0.01）, and 6.01% higher than that of T80 group（P＜0.01）. The feed gain ratio（F/G） of T40 group was the lowest, which was 4.08%（P＜0.01）, 3.14%（P＜0.05）, and 5.60%（P＜0.01） lower than that of T20, T60, and T80 groups, respectively.（2） Compared with T80 group, the apparent digestibility of dry matter（DM）, neutral detergent fiber（NDF）, acid detergent fiber（ADF） and ether extract（EE） of the first three groups were significantly increased（P＜0.05）. The apparent digestibility of crude protein（CP） of T20 group was significantly higher than that of T60 and T80 groups（P＜0.05）, but there was no significant difference between T20 group and T40 group（P＞0.05）.（3） The rumen pH, propionic acid and butyric acid contents were not affected by increasing the proportion of mixed storage（P＞0.05）. However, the concentrations of ammonia nitrogen（NH3-N） and total volatile fatty acids（TVFA） of T60 and T80 groups were significantly lower than those of T20group（P＜0.05）, and the content of acetic acid was significantly higher than that of T20 group（P＜0.01）. The ratio of acetic acid to propionic acid of T80 group was significantly higher than that of T20 and T40 groups（P＜0.05）.（4） Albumin（ALB） content of T20group was significantly higher than that of T60 and T80 groups（P＜0.05）. Urea nitrogen（UN） concentration of T80 group was significantly increased（P＜0.01）, 29.05%, 20.96% and 11.31% higher than that of T20, T40 and T60 groups, respectively. Glucose（Glu） concentration of T20 group was significantly higher than that of T60 and T80 groups（P＜0.01）, and there was no significant difference between T20 group and T40 group（P＞0.05）.（5） The economic benefit of T40 group was the highest（17.96yuan·head-1·d-1）, followed by T20（16.91 yuan·head-1·d-1）, T60（16.79 yuan·head-1·d-1） and T80（15.91 yuan·head-1·d-1）.【Conclusion】In conclusion, with the increase of the proportion of mixed silage instead of silage, the digestibility of nutrients,rumen fermentation and blood biochemical indexes would be affected to some extent. When replacing 40% whole plant maize silage,the production performance was the best and the economic benefit was the highest.

本试验旨在通过感官评定、发酵特性、化学养分分析方法和瘤胃尼龙袋技术等,依据康奈尔净碳水化合物-蛋白质体系(CNCPS),对生马铃薯条加工副产品与稻草混贮和全株玉米青贮的营养特性进行评价和比较,为生马铃薯条加工副产品与稻草混贮在反刍动物养殖中的应用提供参考.结果表明:2种发酵饲料的感官评分均为一级优良.粗蛋白质(CP)和非蛋白氮(NPN)含量在生马铃薯条加工副产品与稻草混贮中最高.生马铃薯条加工副产品与稻草混贮的快速降解蛋白(PB1)和快速降解碳水化合物(CA)含量显著高于全株玉米青贮(P<0.05),不可利用蛋白(PC)含量显著低于全株玉米青贮(P<0.05).与全株玉米青贮相比,生马铃薯条加工副产品与稻草混贮的48 h中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的瘤胃降解率无显著差异(P>0.05).综上所述,生马铃薯条加工副产品与稻草混贮的CP含量高于全株玉米青贮,两者的NDF瘤胃降解率无显著差异,生马铃薯条加工副产品与稻草混贮可以作为反刍动物较好的粗饲料.

旨在探究生薯条加工副产品-稻草混贮(以下简称"薯稻混贮")与全株玉米青贮间的组合效应."薯稻混贮"是按照1:2混合(混贮后的干物质含量为35％)、添加青贮添加剂、用搅拌机混匀、打捆裹包机裹包、发酵60 d制成.根据"薯稻混贮"与全株玉米青贮的不同比例分为7个组合,分别为T0组(0:100)、T20组(20:80)、T40组(40:60)、T50组(50:50)、T60组(60:40)、T80组(80:20)、T100组(100:0),每个组合3个重复.通过体外产气法,测定各组合发酵48 h干物质降解率(DMD)、pH、氨态氮(NH3-N)浓度、微生物蛋白(MCP)产量以及挥发性脂肪酸(VFA)浓度等指标,测定各组合在发酵2、4、6、8、10、12、24、36和48 h的产气量(GP).并计算每个单项组合效应指数(SFAEI)及综合效应指数(MFAEI).结果表明:1)GP和DMD随"薯稻混贮"比例增加显著或极显著降低(P<0.05或P<0.01).SFAEI中T50和T80组的GP和DMD最低,GP和DMD最高值均出现在T20组.2)不同组合发酵后的pH值为6.46～6.59,其中T80组pH最高,显著或极显著高于除T100组外的其他组别(P<0.05或P<0.01),SFAEI在T80组最高.3)各组合间NH3-N浓度、MCP产量无显著差异(P>0.05),但均以T40组最高,而SFAEI分别以T40和T80组最高.4)乙酸、丙酸、戊酸和TVFA浓度均以T0组最高,T100组最低,且两组间差异极显著(P<0.01);丁酸也以T0组浓度最高,但以T80组浓度最低.SFAEI指标中,乙、丙、丁酸分别以T80、T20和T60组最高.通过MFAEI指数评定得出,两种饲料组合均产生正组合效应,其中T40组(40:60)最优,其次是T50组(50:50).

本试验旨在探究玉米秸秆黄贮为主型粗饲料的饲粮能量水平对西门塔尔杂交牛生长性能、养分代谢、屠宰性能和肉品质的影响.选择体况良好、体重相近的西门塔尔杂交牛45头,采用单因素试验设计,随机分成3组,每组15个重复,每个重复1头牛.试验分为前、中、后3个阶段,饲喂3种不同饲粮.前期:各组饲粮粗蛋白质水平均为12.0％,综合净能分别为6.27(Ⅰ组)、6.38(Ⅱ组)和6.48 MJ/kg(Ⅲ组);中期:各组饲粮粗蛋白质水平均为11.6％,综合净能分别为6.43(Ⅰ组)、6.53(Ⅱ组)和6.63 MJ/kg(Ⅲ组);后期:各组饲粮粗蛋白质水平均为11.0％,综合净能分别为6.70(Ⅰ组)、6.80(Ⅱ组)和6.90 MJ/kg(Ⅲ组).试验期137 d,其中预试期15 d,正试期122 d,栓系饲养.结果表明:1)Ⅱ组平均日增重最高,分别较Ⅰ组和Ⅲ组提高了7.91％(P>0.05)和11.11％(P<0.05).2)Ⅱ组粗蛋白质、粗脂肪、中性洗涤纤维和酸性洗涤纤维表观消化率高于Ⅰ组和Ⅲ组,但未达到显著水平(P>0.05).3)Ⅱ组干物质采食量最高,较Ⅰ组和Ⅲ组分别提高2.06％(P>0.05)和6.75％(P<0.05);Ⅱ组料重比最低,增重收入和养殖效益最高.4)与Ⅰ组相比,Ⅲ组血清胆固醇、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇含量显著增加(P<0.05).5)饲粮能量水平对各组屠宰率、净肉率、肉骨比和眼肌面积无显著影响(P>0.05),背膘厚度随饲粮能量水平增加显著提高(P<0.05).6)Ⅲ组背最长肌的剪切力、系水能力和肉色最低,但各组间无显著差异(P>0.05).7)随着饲粮能量水平的提高,背最长肌中的粗脂肪含量逐渐上升,但未达到显著差异水平(P>0.05).综述所述,以玉米秸秆黄贮为主型粗饲料对西门塔尔杂交牛育肥,中能量水平组的平均日增重最高,料重比最低,经济效益最高.在本试验条件下,适宜的能量和粗蛋白质水平为:前期,肉牛综合净能6.38 MJ/kg,粗蛋白质12.0％;中期,肉牛综合净能6.53 MJ/kg,粗蛋白质11.6％;后期,肉牛综合净能6.80 MJ/kg,粗蛋白质11.0％.

本试验旨在研究日粮综合净能(NEmf)水平对体质量500 kg荷斯坦阉牛增重、养分消化率和血液生化指标的影响.选择健康、体况良好、平均体质量为(501.47±40.09) kg的13月龄荷斯坦阉牛60头,采用完全随机设计,试验分为3组,每组20个重复,每个重复1头牛.试验组为低能量组(LE组,5.89 MJ/kg NEmf)、中能量组(ME组,6.10 MJ/kg NEmf)和高能量组(HE组,6.30 MJ/kg NEmf).各试验组粗蛋白质(CP)水平相同.预试期10 d,正试期87 d.结果 显示,提高日粮能量水平对荷斯坦阉牛的平均日增体质量(ADG)无显著性影响(P＞0.05),但显著降低料重比(P＜0.05)和日粮中干物质、脂肪、中性洗涤纤维的表观消化率(P＜0.01);随着日粮能量水平的增加,荷斯坦阉牛血液的GLU和UN无显著性变化(P＞0.05),但显著提高了血液中LPL的活性(P＜0.05),与LE组相比,ME组LDL含量显著提高(P＜0.01),但与HE组无显著性差异(P＞0.05);日粮能量水平的增加对瘤胃pH、NH3-N、VFA无显著性影响(P＞0.05);提高日粮能量水平增加了养殖收益,ME组最高,较LE组和HE组分别增加6.94％和3.10％.结果 表明,在本试验条件下,500～600 kg荷斯坦阉牛日粮CP在11.5％时,适宜能量水平为6.10MJ/kg.