辣木在生长猪上的营养价值评定

本试验通过在生长猪上测定辣木叶和辣木枝的消化能、代谢能和氨基酸标准回肠消化率,旨在评定辣木在生长猪上的营养价值。选择24头回肠末端安装T型瘘管的“杜×长×大”去势公猪,平均体重为(39.80±1.06)kg,随机分为4个组,分别饲喂无氮饲粮、玉米-豆粕型基础饲粮、辣木叶饲粮和辣木枝饲粮,每组6个重复。预饲7 d后,进行4 d消化代谢试验,收集全部粪尿,用于测定消化能和代谢能。消化代谢试验结束后,继续2 d收集回肠食糜用于测定氨基酸表观回肠消化率和标准回肠消化率。结果表明:与辣木枝相比,辣木叶含有较高含量的营养成分,尤其是粗蛋白质、粗脂肪和钙,含量分别为26.29%、6.25%和2.70%。辣木叶的消化能、代谢能和总能表观消化率分别为9.35、8.24 MJ/kg和49.26%,辣木枝的消化能、代谢能和总能表观消化率分别为7.51、6.03 MJ/kg和40.81%,辣木叶的有效能值和总能表观消化率显著高于辣木枝(P<0.05)。辣木叶总必需氨基酸、总非必需氨基酸和粗蛋白质标准回肠消化率分别为42.05%、42.59%和49.03%,而辣木枝总必需氨基酸、总非必需氨基酸和粗蛋白质标准回肠消化率分别为35.13%、37.31%和40.15%,辣木叶的总必需氨基酸、总非必需氨基酸和粗蛋白质标准回肠消化率显著高于辣木枝(P<0.05)。综上所述,辣木叶的消化能、代谢能和总必需氨基酸标准回肠消化率分别为9.35、8.24 MJ/kg和42.05%,而辣木枝的消化能、代谢能和总必需氨基酸标准回肠消化率分别为辣木叶的80.3%、73.3%和83.5%。因此,辣木叶具有更高的营养价值,更适合作为生长猪的蛋白质饲料原料。     

饲料桑粉对生长育肥猪的营养价值评定

选取健康、胎次一致的杜长大三元杂交去势公猪6头,采用全收粪法进行消化试验,测定生长育肥猪对饲料桑粉的各常规营养成分的表观消化率和消化能,确定饲料桑粉对生长育肥猪的营养价值。结果表明,饲料桑粉的总能、总能表观消化率和表观消化能分别为15.70MJ/kg、68.04%和10.66MJ/kg;粗蛋白质含量、表观消化率和可消化粗蛋白质分别为20.04%,76.49%,15.33%;粗脂肪含量、表观消化率和可消化粗脂肪分别为3.55%,29.77%,1.06%;粗纤维含量、表观消化率和可消化粗纤维分别为17.18%,31.52%,5.41%;无氮浸出物含量、表观消化率和可消化无氮浸出物分别为36.64%,81.91%,33.08%。结果提示,饲料桑粉是一种营养价值较高的饲料资源。     

喷雾干燥破膜血球蛋白粉在断奶仔猪上的营养价值评定

试验选用体重(15.6±1.98)kg杜长大仔猪12头,在测定血球蛋白粉常规养分和氨基酸含量基础上进行消化代谢试验。采用单因子试验设计,用无氮日粮和血球蛋白粉半纯合日粮法测定血球蛋白粉中粗蛋白质和能量的消化利用率及猪回肠末端氨基酸的表观消化率。结果表明:血球蛋白粉含粗蛋白质91.87%,总能20.96MJ/kg,总氨基酸71.85%,其中主要限制性氨基酸:赖氨酸、蛋氨酸、苏氨酸和异亮氨酸含量分别为6.32%、0.91%、2.30%、0.36%。粗蛋白质表观和真消化率分别为92.69%和94.34%,总氨基酸回肠表观消化率80.83%,消化能19.28MJ/kg,代谢能19.03MJ/kg。     

大薯在生长猪日粮中能量及常规养分营养价值评定

本试验选择6头去势定安公猪,平均分成2组,采用交叉试验设计,利用替代日粮法研究生长猪对大薯能量及常规养分的利用。试验结果表明,大薯块茎总能值为13.42 MJ/kg,猪表观消化能为11.60 MJ/kg;大薯中常规养分含量分别为干物质83.12%、粗蛋白质4.31%、粗灰分4.01%、粗脂肪0.29%、粗纤维1.5%、中性洗涤纤维15.28%、酸性洗涤纤维7.12%、钙0.09%、总磷0.28%;生长猪对大薯养分表观消化率分别为干物质82.0%、有机物87.0%、总能的表观消化率86.4%、粗蛋白质57.5%、粗灰分48.0%、粗脂肪21.2%、粗纤维31.6%、中性洗涤纤维72.8%、酸性洗涤纤维71.4%、钙36.7%、总磷70.9%。从试验结果可知,大薯的总能和表观消化能分别为玉米的82.8%和83.2%,且能量利用率接近木薯和玉米,属良好能量饲料。但大薯其他常规养分含量低且利用率差,因此在生产应充分考虑补充蛋白质及矿物质等饲料。     

白酒糟的营养价值评定

选取12头平均体重40 kg DLY杂交猪随机分为3组,每组按4×4拉丁方设计,应用套算法,全消化道收粪技术,测定9种白酒糟粗蛋白、粗脂肪、粗纤维、中性洗涤纤维、酸性洗涤纤维、钙、总磷、干物质和总能的表观消化率。结果表明:白酒糟消化能为5.04～8.94 MJ/kg;各营养成分表观消化率分别为粗蛋白29.00%～42.60%、粗脂肪35.21%～72.48%、粗纤维13.39%～24.04%、中性洗涤纤维14.76%～36.24%、酸性洗涤纤维21.64%～32.07%、钙77.50%～85.92%、总磷61.98%～76.70%、干物质25.05%～45.13%、总能31.27%～52.16%。总之,白酒糟营养丰富,来源对其养分含量及表观消化率影响大。     

白酒糟发酵粉对生长猪消化能、代谢能和氨基酸标准回肠消化率的评定

研究旨在分析白酒糟发酵粉的化学组成并测定生长猪的消化能、代谢能及氨基酸标准回肠消化率,同时以豆粕为对比,评价白酒糟发酵粉作为猪蛋白质饲料原料应用的可行性。试验一选用6头杜×长×大三元杂交去势公猪[体重为(35.3±3.5)kg],采用3×3双拉丁方设计,应用套算法,全收粪技术,测定白酒糟发酵粉和豆粕的消化能和代谢能;每个试验期10 d,前5 d为适应期,后5 d为粪尿收集期。试验二选用6头安装简单T型瘘管的杜×长×大三元杂交去势公猪[体重为(32.3±2.8)kg],采用3×3双拉丁方设计,测定白酒糟发酵粉和豆粕的氨基酸标准回肠消化率;每个试验期7 d,前5 d为适应期,后2 d为食糜收集期。结果表明,白酒糟发酵粉和豆粕的消化能分别为9.42 MJ/kg和14.77 MJ/kg;代谢能分别为8.91 MJ/kg和14.39 MJ/kg。白酒糟发酵粉消化能和代谢能均显著低于豆粕(P<0.05),分别为豆粕的64%和62%。白酒糟发酵粉和豆粕必需氨基酸标准回肠消化率分别为59.26%和79.85%;非必需氨基酸标准回肠消化率分别为44.77%和74.72%;总氨基酸标准回肠消化率分别为52.82%和77.57%。除色氨酸和胱氨酸外,均显著低于豆粕(P<0.05)。白酒糟发酵粉的必需氨基酸、非必需氨基酸和总氨基酸的标准回肠消化率分别为豆粕的74%、60%和68%。综上所述,白酒糟发酵粉的消化能、代谢能和氨基酸标准回肠消化率低于豆粕,但仍具有较高的饲用价值。白酒糟发酵粉可作为蛋白质饲料原料应用于养猪生产。     

水解羽毛粉作为生长猪蛋白质原料饲喂效果的研究

研究旨在测定水解羽毛粉的消化能、代谢能及其日粮回肠末端氨基酸消化率。试验1采用全收粪法测定水解羽毛粉消化能及代谢能;试验2采用指示剂法测定水解羽毛粉日粮粗蛋白和氨基酸的表观回肠末端消化率和标准回肠末端消化率。结果表明:干物质基础状态下水解羽毛粉的消化能和代谢能分别为15.04和12.80 MJ/kg,生长猪日粮中添加14.50%水解羽毛粉时,除蛋氨酸外,日粮中粗蛋白质和氨基酸的表观回肠末端消化率和标准回肠末端消化率较低,氮的有效利用率低。     

鸡、鸭、鹅对白酒糟和发酵白酒糟能量利用的比较研究

本试验旨在评价白酒糟和发酵白酒糟的营养成分含量及鸡、鸭、鹅对其的仿生消化总能(SDGE)和代谢能(ME),分别利用仿生消化法和生物学法(排空强饲法)测定。结果表明:1)白酒糟中干物质、粗蛋白质、粗灰分和总磷含量分别为85.63%、18.43%、1.49%和0.21%,均显著低于发酵白酒糟中的89.15%、24.75%、2.37%和0.38%(P0.05);白酒糟中粗脂肪和粗纤维含量分别为4.64%和24.15%,均显著高于发酵白酒糟中的3.61%和15.50%(P0.05)。2)鸡、鸭、鹅对白酒糟的SDGE分别为11.15、11.54和10.02 MJ/kg,均显著低于发酵白酒糟的11.86、12.23和10.78 MJ/kg(P0.05)。3)樱桃谷肉鸭对白酒糟的表观代谢能(AME)为10.42 MJ/kg,真代谢能(TME)为11.29 MJ/kg,能量表观利用率为55.01%,均显著高于杏花公鸡(AME为8.13 MJ/kg,TME为9.39 MJ/kg,能量表观利用率为44.79%)和四川白鹅(AME为8.20 MJ/kg,TME为9.16 MJ/kg,能量表观利用率为43.91%)(P0.05);而杏花公鸡、樱桃谷肉鸭、四川白鹅对发酵白酒糟的AME、TME、能量表观利用率和能量真利用率则无显著差异(P0.05)。由此可见,发酵白酒糟中的粗蛋白质、总磷含量高于白酒糟,粗纤维含量低于白酒糟;鸡、鸭、鹅对发酵白酒糟的SDGE均高于白酒糟;樱桃谷肉鸭对白酒糟的ME高于杏花公鸡、四川白鹅;而杏花公鸡、樱桃谷肉鸭、四川白鹅对发酵白酒糟的ME则无显著差异。     

白酒糟、啤酒糟和米酒糟对肉鸡的营养价值比较

本试验旨在比较白酒糟、啤酒糟和米酒糟在肉鸡上的营养价值。试验选取24只平均体重为(1.00±0.12)kg的42日龄湘黄肉公鸡,随机分为4组,每组6个重复,每重复1只鸡。按照4×4拉丁方设计,4组肉鸡分别饲喂100%基础饲粮、80%基础饲粮+20%白酒糟、80%基础饲粮+20%啤酒糟、80%基础饲粮+20%米酒糟。预饲7 d后连续4 d收集鸡只的粪便,测定酒糟、饲粮和粪便的养分含量,应用套算法计算白酒糟、啤酒糟和米酒糟的养分表观消化率。结果显示:米酒糟、白酒糟、啤酒糟的表观消化能分别为7.11、8.39、12.26 MJ/kg;粗脂肪含量分别为8.65%、7.66%、0.44%;粗纤维含量分别为11.22%、4.78%、21.61%。啤酒糟的粗脂肪表观消化率为25.64%,与白酒糟的28.54%差异不显著(P0.05),但显著低于米酒糟的59.56%(P0.05)。白酒糟的粗纤维表观消化率为55.41%,显著高于啤酒糟的38.74%和米酒糟的30.05%(P0.05)。白酒糟的各氨基酸表观消化率介于25.67%~62.27%,米酒糟的介于15.22%~79.04%,啤酒糟的各氨基酸表观消化率要稍高些,介于50.72%~90.10%。总之,不同酒糟间养分含量及养分表观消化率差异较大,啤酒糟虽粗纤维含量高,但其氨基酸表观消化率普遍较高。     

脱脂米糠日粮添加复合酶制剂和阿魏酸酯酶对生长猪养分消化率的影响

试验旨在研究脱脂米糠日粮添加多糖酶-植酸酶复合酶制剂和阿魏酸酯酶对生长猪养分消化率的影响。试验用6头安装回肠末端瘘管,初始体重约18㎏的阉割公猪(杜洛克×大白猪×长白猪)按3×3重复拉丁方设计,随机分为3组,分别饲喂基础日粮(D),基础日粮+300 mg/kg复合酶(DC),基础日粮+300mg/kg复合酶+700 mg/kg阿魏酸酯酶(DCF)3种饲粮。结果表明,添加复合酶制剂能显著提高生长猪回肠末端干物质、灰分、粗纤维和总能在表观消化率,以及灰分和钙在全消化道表观消化率(P<0.05)。日粮中再添加阿魏酸酯酶能显著提高生长猪回肠末端灰分和钙表观消化率以及灰分在全消化道表观消化率(P<0.05)。酶制剂添加并不影响生长猪回肠末端氨基酸表观消化率(P>0.05)。结果提示复合酶制剂和阿魏酸酯酶可以改善米糠日粮在生长猪中的养分消化率。     

白酒糟酵母培养物对产蛋鸡生产性能、免疫机能和肠黏膜结构的影响

本试验旨在探讨饲粮中添加白酒糟酵母培养物对产蛋鸡生产性能、免疫机能及肠黏膜结构的影响。选取324只27周龄、产蛋率和体重相近的健康海兰褐蛋鸡,随机分成3个组,每组6个重复,每个重复18只鸡。3组产蛋鸡分别饲喂添加0(对照)、1%和2%白酒糟酵母培养物的玉米-豆粕型饲粮,试验分为预试期1周和正试期8周。结果表明:1)各时间段内各组间产蛋率差异不显著(P0.05),但1%白酒糟酵母培养物组产蛋率在1~4周、5~8周和1~8周比对照组分别提高了1.79%、2.07%和1.93%;1%白酒糟酵母培养物组5~8周和1~8周的平均日采食量有高于对照组的趋势(P0.10)。2)在第4周末,2%白酒糟酵母培养物组血清球蛋白含量较对照组和1%白酒糟酵母培养物组分别提高了19.0%(P0.10)和27.2%(P0.05),1%和2%白酒糟酵母培养物组血清磷含量均显著高于对照组(P0.05)。3)在第4周末,与对照组和1%白酒糟酵母培养物组相比,2%白酒糟酵母培养物组血清免疫球蛋白G和免疫球蛋白M含量均显著提高(P0.05);在第8周末,与对照组相比,2%白酒糟酵母培养物组血清免疫球蛋白A和免疫球蛋白M含量显著提高(P0.05),1%白酒糟酵母培养物组血清溶菌酶活性显著提高(P0.05)。4)与对照组和2%白酒糟酵母培养物组相比,饲粮中添加1%白酒糟酵母培养物显著提高了产蛋鸡空肠绒毛高度和隐窝深度(P0.05),有提高绒毛高度/隐窝深度的趋势(P0.10)。综上可知,产蛋鸡饲粮中添加适量(1%~2%)白酒糟酵母培养物可增强免疫机能,改善肠黏膜结构。     

Effects of Feeding Distiller's Dried Grains with Solubles on Growth and Feed Efficiency of Weanling Horses

The effects of replacing corn and soybean meal with distiller's dried grains and solubles in the weanling horse diet were examined. Sixteen weanling horses, 12 fillies and four colts, were fed completely pelleted diets consisting of 50% alfalfa in addition to 50% of a concentrate containing either corn and soybean meal (CS), or 30% of the concentrate replaced with distiller's dried grains with solubles (DDGS). There were no significant differences (P > .05) between the two diets in either average daily gain or gain-to-feed ratio. The CS diet had a higher apparent dry matter digestibility (P < .0001), and higher apparent digestibility of crude protein (CP), acid detergent fiber (ADF), and neutral detergent fiber (NDF) (P < .01). It was concluded that replacing a portion of the corn and soybean meal with distiller's dried grains with solubles in the weanling horse diet did not lead to significant growth depression. However, the diet containing DDGS had reduced apparent digestibility of dry matter, CP, and fiber. Therefore, it was concluded that it may not be advisable to replace more than 30% of the concentrate portion or 15% of the total diet with distiller's dried grains and solubles when alfalfa is used as the forage source constituting 50% of the weanling diet. Even less DDGS may be desirable to substitute for corn and soybean meal in weanling horse diets if the forage source is one with lower protein quality than alfalfa. It is possible that using DDGS for less than 30% of the concentrate portion of the diet along with high-quality alfalfa forage may produce comparable gain and feed efficiency results with less depression of apparent digestibility of dry matter, crude protein, and fiber.     

复合酶制剂对几种糟渣类原料养分利用率和代谢能的影响

本试验旨在研究临武鸭对几种糟渣类原料(白酒糟、啤酒糟、2种酱油渣、灵芝菌糠、柑橘渣和甘蔗糖渣)的养分利用率和代谢能,及添加复合酶制剂(蛋白酶、纤维素酶和木聚糖酶)对几种糟渣类原料养分利用率和代谢能的影响。试验选用48只体重2.0 kg左右的健康成年临武鸭公鸭,随机分为8组,每组6个重复,每重复1只鸭。采用绝食强饲-全收粪法进行代谢试验,将待测原料与无氮饲粮按1∶2的重量比混合配成试验原料,每种原料均设对照组和添加复合酶制剂组(试验原料中添加250 mg/kg的复合酶制剂),对照组和添加复合酶制剂组的试验分2个批次进行,测定添加复合酶制剂对临武鸭几种糟渣类原料养分利用率和代谢能。结果表明:临武鸭对几种糟渣类原料的干物质(DM)、粗蛋白质(CP)、粗脂肪(EE)和粗纤维(CF)表观利用率分别为30.73%~51.08%、17.65%~75.62%、10.85%~91.19%和10.84%~67.05%,表观代谢能(AME)和真代谢能(TME)分别为4.58~15.20 MJ/kg和5.57~17.17 MJ/kg。添加复合酶制剂后临武鸭对几种糟渣类原料的DM、CP、EE和CF的有效营养改进值(ENIV)分别为6.46~41.37 g/kg、0.33~13.23 g/kg、0.09~9.73 g/kg和0.70~7.84 g/kg,TM E提高了0.13~1.68 M J/kg。由此可见,添加复合酶制剂能够一定程度地提高临武鸭对糟渣类原料的养分利用率和代谢能。     

鳙鱼对10种蛋白质饲料原料中营养物质的表观消化率

本试验旨在研究鳙鱼(Aristichthys nobilis)对鱼粉(国产)、干酒糟及其可溶物(DDGS)、菜籽粕、米糠、豆粕、酶解羽毛粉、棉籽粕、小麦麸、玉米蛋白粉和花生粕中干物质、粗蛋白质、粗脂肪、总能以及氨基酸的表观消化率。试验饲料按照基础饲料和待测饲料原料7∶3的比例构成,并添加0.5%的三氧化二钇(Y2O3)作为外源指示剂。挑选初体重为(290.02±2.82)g的鳙鱼,随机分成11组,每组3个重复,每个重复10尾鱼。随机选取1组作为对照组投喂基础饲料,剩余10组为试验组分别投喂试验饲料。投喂1周后通过虹吸法收集粪便。结果表明:1)10种饲料原料中干物质、粗蛋白质、粗脂肪和总能的表观消化率的范围分别为69.9%~85.7%、73.5%~88.3%、81.2%~91.1%和81.9%~86.3%。2)在10种饲料原料中,米糠总能的表观消化率最高,而鱼粉的干物质、粗蛋白质和粗脂肪的表观消化率最高;酶解羽毛粉的干物质、粗脂肪和总能的表观消化率最低,玉米蛋白粉的粗蛋白质的表观消化率最低。3)各饲料原料氨基酸的表观消化率基本维持在65.59%~99.17%,且都以小麦麸较低。由此可见,鳙鱼对鱼粉具有很好的利用效果,其次是豆粕和花生粕,而酶解羽毛粉中粗蛋白质的表观消化率最低,小麦麸各氨基酸的表观消化率均比较低。     

Effect of supplementation of xylanase and phospholipase to a wheat-based diet for weanling pigs on nutrient digestibility and concentrations of microbial metabolites in ileal digesta and feces

The objective of this study was to determine the effect of supplementing a wheat-based diet with xylanase and phospholipase either alone or in combination on the ileal and fecal digestibilities of nutrients and energy in early-weaned pigs. In addition, the concentrations of ammonia, lactate, and VFA were measured in ileal digesta and feces. The experiment was carried out with 16 barrows weaned at the age of 11 d with an average initial BW of 4.1 kg. On d 4 and 5 postweaning, the piglets were fitted with a simple T-cannula at the distal ileum. The experiment was designed as a balanced incomplete block design with three periods. The piglets received the basal diet with or without supplementation of either xylanase or phospholipase or a combination of these. There was a positive (P = 0.005 to 0.018) effect on the digestibility values of GE, OM, CP, crude fiber (CF), and NDF with xylanase supplementation. Apart from lysine, threonine, cysteine, glycine, and proline, the digestibility values of all AA were improved (P = 0.001 to 0.024). Phospholipase supplementation had a positive effect on CP (P = 0.047) and CF (P = 0.002) digestibilities, but no effect on ether extract (EE) digestibility. Supplementation of both enzymes showed the largest response in nutrient digestibilities, except that EE digestibility was not affected. No differences were found in D-/L- lactate, and ammonia concentrations among treatments. Acetate and propionate concentrations tended to increase when xylanase was supplemented and were highest for the combination of both enzymes. Despite the positive effects on ileal nutrient and energy digestibilities, there was no effect of xylanase or the combined enzyme supplementation on the fecal digestibilities of OM, CP, EE, CF, NDF, ADF, or GE, and on fecal concentrations of VFA. Phospholipase alone slightly decreased the total-tract nutrient and energy digestibilities (P < 0.05). In conclusion, the combination of both enzymes generally led to the highest increases in ileal digestibilities, which were of small numerical magnitude (approximately 2%). However, on a relative basis, this increase of 2% represents approximately 13% of the remaining diet that was available for digestion based on the fact that approximately 15% of the diet was not digested in the control pigs. Thus, the potential benefits in the nutrition of weanling pigs from combinations of enzymes should be validated under practical conditions.     

Effect of fumaric acid and dietary buffering capacity on ileal and fecal amino acid digestibilities in early-weaned pigs

Experiments were conducted to determine the effect of fumaric acid supplementation and buffering capacity of the diet on ileal and fecal digestibilities of CP, GE, and amino acids in early-weaned pigs. In two experiments, 12 pigs each were weaned at 14 d of age and fitted with a simple T-cannula at the distal ileum between 15 and 17 d of age. In both experiments, the pigs were fed four diets, based on wheat and soybean meal without (control) or with 1, 2, or 3% fumaric acid according to a balanced two-period change-over design. In Exp. 2, the buffering capacity of the diets was increased by supplementation of 3% sodium bicarbonate. The pigs were fed three times daily: equal amounts at 8-h intervals. The diets were supplied at a rate of 5% (wt/wt) of body weight. The inclusion of fumaric acid to the diet with a low buffering capacity increased (P < .05) the ileal digestibilities of CP, GE, and the majority of amino acids. The highest responses were found at an inclusion level of 2% fumaric acid. The improvements in apparent ileal amino acid digestibilities ranged from 4.9 to 12.8 percentage units. Supplementation of fumaric acid to a diet with a high buffering capacity led only to numerical increases in ileal digestibilities of CP, GE, and amino acids. In both studies, fumaric acid supplementation had no effect (P > .05) on the fecal digestibilities of CP, GE, and amino acids, except histidine. A high buffering capacity of the diet decreased the ileal amino acid digestibilities by 1 to 10 percentage units compared with diets with the low buffering capacities. In both experiments, ileal and fecal digestibilities were higher (P < .05) in Period 2 (on d 24 after weaning) than in Period 1 (on d 11 after weaning). A positive correlation (P < .05) between ileal digestibilities and fumaric acid supplementation to the diets with the low buffering capacities was observed in Period 1 (on d 11 after weaning), but not in Period 2 (on d 24 after weaning). No relationship (P > .05) between ileal digestibilities and fumaric acid supplementation to the diets with a high buffering capacity could be established. In conclusion, supplementation of fumaric acid to starter diets during the first 3 to 4 wk after weaning increases the ileal digestibilities of GE, CP, and amino acids.     

青鱼对8种饲料原料中营养物质的表观消化率

本试验旨在研究青鱼(Mylopharyngodon piceus)对国产鱼粉、蝇蛆粉、玉米蛋白粉、大豆粕、花生粕、棉籽粕、菜籽粕和米糠8种饲料原料干物质、粗蛋白质、氨基酸、粗脂肪、总磷和总能的表观消化率。试验饲料由70%基础饲料和30%待测饲料原料组成,并以0.1%的三氧化二钇(Y2O3)为外源指示剂。选取平均体重为(60.17±1.28)g的青鱼270尾,随机分成9组,每组3个重复,每个重复10尾鱼。对照组试验鱼饲喂基础饲料,试验组试验鱼分别饲喂1种试验饲料。饲喂1周后采用自排法收集粪便待测。结果表明:8种饲料原料的干物质、粗蛋白质、粗脂肪、总磷、总能以及总氨基酸的表观消化率的范围分别是62.17%～86.47%、83.34%～95.84%、78.93%～100.06%、37.33%～81.99%、66.75%～89.86%、86.33%～96.58%。在8种饲料原料中,玉米蛋白粉的干物质、总磷和总能的表观消化率最高,而大豆粕的粗蛋白质、粗脂肪和总氨基酸的表观消化率最高;棉籽粕的干物质和总能的表观消化率最低,米糠的粗脂肪和总磷的表观消化率最低。各饲料原料中总氨基酸表观消化率与粗蛋白质表观消化率的变化趋势一致,其中以蝇蛆粉最低。由此可见,大豆粕和玉米蛋白粉是青鱼的优质植物蛋白质源,可适量替代鱼粉;蝇蛆粉中粗蛋白质和氨基酸的消化率都较低,在青鱼饲料中的添加量不宜过高;花生粕、棉籽粕和菜籽粕也是较好的植物性蛋白质源,在青鱼饲料中适量添加既有利于饲料的营养平衡,还可降低饲料成本;米糠作为青鱼的能量原料必须保持新鲜,并控制其在饲料中的用量。     

饲喂频率对生长猪饲粮养分消化率的影响

为研究饲喂频率对生长猪总能(GE)和养分的表观回肠消化率(AID)和表观全肠道消化率(ATTD)的影响,试验将24头回肠末端安装简单T型瘘管、平均初始体重为(40.7±1.3)kg的生长猪随机分到M2组(每天饲喂2次)和M12组(每天饲喂12次),每个处理组12个重复,每个重复1头猪。试验期共9 d,包括5 d适应期,2 d粪样收集期和2 d食糜收集期。结果表明:平均日采食量(ADFI)、平均日增重(ADG)和耗料增重比不受饲喂频率的影响(P0.1);饲喂频率对粗灰分、干物质(DM)、粗脂肪(EE)、碳水化合物(CHO)、粗蛋白(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)以及GE的AID无显著影响(P0.1);M2组的粗灰分、DM、EE、CP、NDF和GE的ATTD显著低于M12组(P0.05);M2组EE和ADF(P0.05)、NDF(P0.01)的后肠道消化率显著低于M12组;M2组ADF和CP的ATTD以及GE的后肠道消化率有低于M12组的趋势(P0.1)。由此可见,生长猪饲喂玉米-豆粕型饲粮,GE和养分的AID不受饲喂频率的影响,但增加饲喂频率能提高GE和养分的后肠消化率和ATTD。