优生素对草杂鸡生长性能的影响

本试验研究了优生素对草杂雏鸡生长性能的影响.试验选用100只1日龄草杂雏鸡,随机分为两组,即对照组和试验组,50只/组.基础日粮相同,优生素按照500g/t添加到基础日粮中.结果表明,试验组鸡的日增重比对照组高,差异显著(P＜0.05);采食量试验组鸡比对照组低,但差异不显著(P＞0.05);料肉比试验组鸡比对照组低,差异不显著(P＞0.05);由此可知,优生素可提高雏鸡日增重和饲料转化率.     

木瓜粉对新西兰白兔生产性能和免疫功能的影响

选取断奶新西兰白兔96只,随机分为4组,对照组饲喂基础日粮,试验Ⅰ,Ⅱ,Ⅲ组在基础日粮中分别添加2%,5%和8%的木瓜粉。经60 d饲养试验显示：前30 d,试验各组日增重、采食量比对照组显著提高（P＜0.05）;料重比差异不显著（P＞0.05）。试验后30 d,试验各组日增重显著高于对照组（P＜0.05）;采食量、料重比组间差异不显著（P＞0.05）。各试验组的血清胆固醇含量显著高于对照组（P＜0.05）;与对照组相比,试验Ⅲ组总蛋白指标显著提高（P＜0.05）,试验Ⅰ组显著下降（P＜0.05）;总球蛋白,IgG,IgA,IgM指标,组间差异均不显著（P＞0.05）。结果表明,在饲料中添加木瓜粉能提高肉兔的生长性能,适宜添加量为5%;木瓜粉有提高肉兔免疫力趋势。     

混菌固态发酵饲料对生长育肥猪生产性能的影响

选用体质量为(20.68±0.82) kg左右的杜长大三元杂交仔猪120头进行试验,研究饲粮中添加混菌固态发酵饲料替代部分豆粕对生长育肥猪生长性能的影响.采用单因子完全随机设计,试验猪随机分成4个组,第一组为豆粕对照组;第二组为2.5%混菌固态发酵饲料替代组;第三组为5%混菌固态发酵饲料替代组;第四组为7.5%混菌固态发酵饲料替代组.试验猪体质量达到100 kg时屠宰,测定胴体性状和血清生化指标.与对照组相比较,各试验组的平均日采食量均差异不显著(P＞0.05),但饲料转化率均有所提高,并缩短了育肥时间,其中第三组达到显著水平(P＜0.05);与对照组相比,各试验组的平均日增体质量均有所增加,而第三组和第四组达到显著水平(P＜0.05);猪的腹泻率比对照组显著降低 (P＜0.05);饲喂混菌固态发酵饲料虽然不显著影响育肥猪的胴体质量、瘦肉率、肌内脂肪、滴水损失和pH值(P＞0.05),但可显著降低背膘厚度(P＜0.05)和提高其屠宰率(P＜0.05).试验各组血液各生化指标与对照组差异不显著(P＞0.05),但第三组甘油三酯含量显著降低(P＜0.05).这些研究结果揭示,在育肥猪日粮中添加混菌固态发酵饲料可提高饲料转化率和平均日增体质量,缩短育肥时间,一定程度上改善胴体品质和健康状况.     

黄芪多糖对小尾寒羊生长性能与血清生化指标的影响

为研究饲料添加不同比例黄芪多糖对小尾寒羊生长性能与血清生化指标的影响,试验将80头年龄、体重和性别一致的小尾寒羊分为4组,分为对照组和3个试验组,每组4个重复,每个重复5只,对照组饲喂基础饲粮,试验组Ⅰ、Ⅱ和Ⅲ在基础饲粮中添加0.05%、 0.10%和0.15%,预试验10d,正式试验60d。与对照组相比,试验Ⅲ组羊群采食量提高明显,3个试验组均提高了羊群日增重水平,显著提高血清中IgG、 IgA、 IgM和IFN-γ含量,但胆固醇含量降低。结果表明:饲料中添加适量黄芪多糖有利于提高小尾寒羊生长性能,提高机体免疫性能。     

亚甲基水杨酸杆菌肽对热应激状态下马岗肉鹅生长性能 和血液生化指标的影响

为研究亚甲基水杨酸杆菌肽(BMD)对热应激状态下肉鹅生长性能和血液生化指标的影响,选取45日龄的健康马岗肉鹅160只,按体重一致原则随机分成对照组和试验组,每组4个重复,每个重复20只鹅(公母各半)。对照组采食基础日粮,试验组日粮在基础日粮中添加100mg/kgBMD。试验期20d,试验期间温度为30~35℃。结果表明,马岗肉鹅的日均采食量、日均增重、腿肌率、胸肌率、SOD活性、T-AOC活性、T3水平、T4水平、TP浓度均表现为试验组显著高于对照组;料重比、腹脂率、LDH活性、GOT活性、GPT活性、AKP活性、MDA含量、BUN含量,试验组显著低于对照组;屠体率、半净膛率、全净膛率、GSH-PX活性,对照组与试验组间无显著差异。添加100mg/kgBMD可以改善热应激肉鹅血液生化指标,提高肉鹅屠宰性能,提高采食量,促进生长和提高饲料转化率。     

CC-Dp对伊犁马驹麦草采食量和生长性能的影响

[目的]在日粮精料补充料中添加CC-Dp对马驹麦草采食量和生长性能的影响.[方法]试验采取单因素随机分组试验设计,选取20匹17月龄健康无病、体况和采食量相近的伊犁马母驹随机分为4个处理组(n=5),即对照组和试验(Ⅰ、Ⅱ、Ⅲ)组,对照组饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ组分别按500、1 000和1 500mg/kg量将CC-Dp添加在基础日粮精料补充料中饲喂.[结果]添加CC-Dp 1 500 mg/kg组试验马驹全期平均麦草采食量提高了7.78; (P ＜0.05),全期日增重提高了10.18; (P ＜0.05);CC-Dp 500和1 000 mg/kg两组的平均麦草采食量和日增重都有增加的趋势(P＞0.05);而试验组与对照组马驹体尺指标并无显著差异.[结论]日粮中添加1 500 mg/kg CC-Dp,能够显著提高马驹麦草采食量,有效促进马驹体增重,提高生长性能.     

中草药添加剂对犊牛生产性能和血液生化指标的影响

为了研究中草药饲料添加剂对犊牛生产性能和血液生化指标的影响,选取西门塔尔杂交犊牛24头,将其分为3组,对照组饲喂基础日粮,试验组添加不同组方的中草药添加剂。90 d后供试牛称重、采集血液生化检测。结果显示,试验组1和试验组2日均采食量和日均增重都显著高于对照组（P＜0.05）;试验组2料重比（8.27）明显低于对照组（9.89）和试验组1（9.36）;两试验组IgG水平显著高于对照组(P＜0.05),且试验组2血清IgA水平显著高于试验组1(P＜0.05);对照组血清总胆固醇（CHO）显著高于试验组2(P＜0.05);试验组2血清钙显著高于对照组和试验组1(P＜0.05);3组牛的其余血液生化指标差异不显著(P＞0.05)。因此,日粮中添加中草药添加剂可明显改善犊牛的生产性能、免疫功能,且对机体没有产生毒副作用。     

纳豆芽孢杆菌的制备及其对番鸭生产性能的影响

采用液态发酵法和固态发酵法制备纳豆芽孢杆菌,并研究日粮中添加不同浓度纳豆芽孢杆菌制剂对番鸭生产性能的影响.结果表明:采用周态发酵法制备纳豆芽孢杆菌优于液态发酵法;在番鸭基础日粮中添加0.2％和0.4％纳豆芽孢杆菌制剂可显著提高番鸭日增重(P＜0.05)、采食量(P＜0.05)和饲料转化率(P＜0.01),以添加0.4％纳豆芽孢杆菌制剂的效果最佳.而日粮中添加0.1％纳豆芽孢杆菌制剂对番鸭日增重、采食量和饲料转化率的作用均不显著(P＞0.05).     

蛋氨酸羟基异丙酯对犊牛生长、血清生化指标和激素水平的影响

本试验旨在通过在犊牛日粮精料补充料中添加蛋氨酸羟基异丙酯(HMBi),研究其对犊牛生长、血清生化指标以及激素水平的影响。选择3.5月龄、体质量相近的雪龙黑牛与徐州黄牛杂交肉犊牛12头,进行配对,随机分为对照组和试验组,每组6头,在相同的条件下饲养。对照组在精料补充料中不添加HMBi,试验组每头犊牛分别在精料补充料中添加4 g/d的HMBi。试验期间,记录犊牛每天的采食量和粪便形态。试验期1 d、28 d、49 d早晨空腹称量每头牛的体质量,测量体高、体长、胸围和管围等体尺指标。试验期开始和结束前颈静脉采血测定血液指标和激素水平。结果显示,与对照组相比,试验组犊牛的体质量变化不显著(P0.05);在第1~7 d时的粗料采食量显著高于对照组(P0.05);腹泻率极显著低于对照组(P0.01);第28 d的胸深显著高于对照组(P0.05)。血清生化指标方面,试验组血清甘油三酯(TG)显著降低(P0.05);血清尿素氮(BUN)在试验后较试验前显著降低(P0.05)。血液激素方面,试验组犊牛血清胰岛素(INS)、瘦素(LEP)以及生长激素(GH)、类胰岛素生长因子1(IGF-1)水平与对照组相比,差异不显著(P0.05)。表明,在日粮精料补充料中添加4 g/d的HMBi能降低犊牛腹泻率,促进胸深发育,促进机体脂肪和蛋白沉积,但对血液激素水平影响不显著。     

碱贮真姬菇菌糠对育肥羊生产性能、屠宰性能及血液生化指标的影响

选取24只体重相近(20 kg±5 kg)的川中黑山羊,随机分为4组,每组6只.对照组育肥羊饲喂不添加碱贮真姬菇菌糠的日粮,试验Ⅰ、Ⅱ、Ⅲ组育肥羊分别饲喂添加20%、30%和40%碱贮真姬菇菌糠的日粮,预饲期14 d,正饲期60 d,研究碱贮真姬菇菌糠对育肥羊生产性能、屠宰性能及血液生化指标的影响.结果表明,在日粮中添加不同水平的碱贮真姬菇菌糠可以降低饲料成本,提高经济效益且对育肥羊的生产性能、屠宰性能及血液生化指标没有不良影响.试验Ⅰ、Ⅱ、Ⅲ组育肥羊的平均日采食量较对照组分别提高了12.28%、16.37%和5.85%(P0.05);试验组育肥羊的屠宰性能较对照组有提高的趋势,但差异不显著;试验组育肥羊血液中谷胱甘肽过氧化物酶和超氧化物歧化酶的活性较对照组均有提高,但差异不显著;试验Ⅱ组育肥羊的瘤胃重量和瘤胃指数较对照组分别提高了22.00%和12.03%(P0.05),总胆固醇浓度较对照组提高了28.95%(P0.05).综合评定结果显示,添加30%碱贮真姬菇菌糠的效果最佳.     

真菌酶制剂对断奶仔猪生长性能的影响

在仔猪同基础日粮中试验组分别为０．３％、０．５％和０．８％真菌酶制剂,进行饲喂试验。结果表明：真菌酶制剂添加水平在０．０％～０．５％范围内明显提高了仔猪采食量（ＦⅠ）、蛋白质摄入量（ＰⅠ）、日增重（ＡＤＧ）和饲料转化率,且以０．５％的添加水平效果最佳。将真菌酶制剂、真菌酶制剂与麦饭石合剂及基础饲料饲喂断奶仔猪,测定其生产性能和血液生化指标。结果表明,试验前期血液总蛋白、球蛋白、血红蛋白、碱性磷酸酶     

白头翁皂苷B4对犊牛生长性能、消化代谢和瘤胃发酵的影响

【目的】通过探究白头翁皂苷B4对犊牛生长性能、消化代谢和瘤胃发酵参数的影响。为新型饲料添加剂的开发提供理论基础。【方法】试验选取60头新生荷斯坦公犊牛,随机分为4组(每组15头),分别饲喂0(C组)、15(A1组)、30(A2组)、45(A3组)mg·d^-1的白头翁皂苷B4。试验周期为56d。在犊牛14、28、42和56日龄晨饲前称量体重,并在28、42和56日龄晨饲后2 h采集瘤胃液,测定瘤胃发酵参数。分别在42和63日龄进行两期消化代谢试验,测定营养物质表观消化率和能氮代谢指标。【结果】(1)白头翁皂苷B4对哺乳期犊牛体重和干物质采食量无显著影响(P>0.05),但犊牛14—28日龄的平均日增重与白头翁皂苷B4呈显著正相关(P<0.05),饲料转化比与添加量呈显著负相关(P<0.05),其中A3组犊牛的平均日增重显著高于C组(P<0.05),饲料转化比显著低于C组(P<0.05)。(2)A3组犊牛7—56日龄和7—14日龄的粪便评分和腹泻率显著低于C组(P<0.05),A2组犊牛15—28日龄的粪便评分和腹泻率显著低于C组(...     

颗粒精料对黑白花公犊复胃消化代谢的影响

用4头装有瘤胃瘘管和十二指肠双筒T形瘘管的黑白花公犊,研究颗粒精料对复胃消化代谢的影响。试验分粉状精料期(Ⅰ期)和颗粒精料期(Ⅱ期)。两期精料成分和量完全相同。粗料为青草,计量自由采食。试验结果表明:Ⅱ期与Ⅰ期相比,平均每kg体重青草采食量和干物质摄入量分别提高了42.97％(P<0.01)和57.35％(P<0.01);复胃纤维素、干物质和有机质消化率分别提高了7.94％(P<0.01),13.03％(P<0.01)和10.61％(P<0.05);瘤胃总挥发性脂肪酸浓度变化不明显(P>0.05)。但乙酸(C_2)百分比升高(P<0.01),丙酸(C_3)和戊酸(C_5)百分比降低(P<0.01),C_2/C_3升高(P<0.01),丁酸(C_4)变化不明显(P>0.05)。两期氨氮浓度无明显差异(P<0.05);瘤胃液平均pH由6.46升到6.67(P<0.01)。Ⅱ期十二指肠食糜流量增加了18.20％(P<0.01);食糜总蛋白、总徽生物蛋白、过瘤胃蛋白和非氨氮量分别提高了26.02％(P<0.01),38.28％(P<0.05),30.63％(P<0.01)和24.66(P<0.01).结果表明颗粒精料能促进犊牛粗饲料采食量,提高复胃纤维素消化率,改变瘤胃发酵类型,减少饲料蛋白在瘤胃的分解,增大进入十二指肠食糜量和非氨氮,从而提高了饲料蛋白和纤维素的利用效率。     

植酸酶和益生素对青年蛋鸡生长性能的影响

将510只45日龄罗曼褐壳蛋鸡随机分为5个处理,每处理6个重复,每重复17只。设计5种饲粮:(1)正对照组;(2)负对照组(营养水平降低10%,钙和总磷除外);(3)负对照组+0.02%植酸酶(降低总磷和有效磷0.05%);(4)负对照组+0.15%益生素;(5)正对照组+0.02%植酸酶(降低总磷和有效磷0.10%)。结果表明:(1)负对照组蛋鸡生长速度与正对照组相当,但粪中干物质(P<0.05)和钙含量(P<0.01)显著提高;(2)负对照组添加植酸酶后,鸡粪磷排泄量极显著减少(P<0.01);与正对照组相比,采食量增加(P<0.01),鸡粪钙含量提高(P<0.05);(3)添加益生素后,蛋鸡采食量增加(P<0.01),其余所观测指标不受影响(P>0.05);(4)正、负对照组饲粮添加植酸酶后,磷表观代谢率分别提高30.06%(P=0.09)和29.05%(P>0.05);(5)高麸皮饲粮组(处理2和3)与低麸皮饲粮组(处理1和5)鸡生长性能相当。     

Effects of formic acid and corn flour supplementation of banana pseudostem silages on nutritional quality of silage,growth, digestion,rumen fermentation and cellulolytic bacterial community of Nubian black goats

The objective of this study was to evaluate the effects of adding formic acid and corn flour supplementation to banana pseudostem silages on the nutritional quality of these silages, growth, digestion, rumen fermentation and cellulolytic bacterial community of Nubian black goats fed these silages. Banana pseudostem silage was prepared either conventionally without any additives(CON) or mixed with 0.6% formic acid(F), 10% corn flour(C), or both(F+C). Four experimental diets containing 40% of the corresponding silages were designed with roughage to concentrate ratio of 50:50(dry matter(DM) basis). A total of 48 Nubian black castrated goats(body weight(BW),(22.64±1.82) kg; 4-mon-old) were randomized into one of the four treatment groups with 12 replicates of one castrated goat per replicate for each treatment in a completely randomized design. Each group was fed on one of the four experimental diets for 40 days. A factorial arrangement of treatments of 2(formic acid levels: 0 and 0.6%)×2(corn flour: 0 and 10%) was adopted. Formic acid supplementation increased(P0.05) average daily gain, as well as lactic acid, propionate and butyric acid and water-soluble carbohydrate concentrations, but decreased(P0.05) the feed conversion rate, p H value, acetate/propionate ratio, and butyric acid concentration relative to the CON group. Corn flour supplementation increased(P0.05) the apparent digestibility of crude protein, neutral detergent fiber, and non-fibrous carbohydrate and Fibrobacter succinogenes, Ruminococcus albus, and Butyrivibrio fibrisolvens populations, but decreased(P0.05) the Ruminococcus flavefaciens population relative to the CON group. There were no F×C treatment interactions(P0.05) for any of the other indices except for the apparent digestibility of non-fibrous carbohydrate(NFC)(P0.05). The results demonstrated that adding 0.6% formic acid and 10% corn flour supplementation to banana pseudostem silages improved the nutritional quality of these silages and enhanced the growth performance of Nubian black castrated goats by improving apparent nutrient digestibility, and regulating ruminal fermentation and bacteria populations.     

Long term effects of artificial rearing before weaning on the growth performance,ruminal microbiota and fermentation of fattening lambs

Early life intervention is important to shape the gut microbiome profiles of adult animals due to the tremendous alteration of diet components. Nevertheless, there is still no unified understanding about its long-term effects in lambs. In this study, sixty 20-day-old lambs were assigned into ewe-rearing (ER) and artificial-rearing (AR) treatments to evaluate the effects of AR strategy on ruminal microbiota, fermentation, and morphology of pre-weaning lambs (from 20 to 60 days of age) and its long-term effects in the fattening stage (from 61 to 180 days of age). During the pre-weaning stage, ER lambs were breastfed and supplemented starter, while AR lambs were artificially fed with milk replacer and starter. During the fattening stage, all lambs in both treatments were fed with the same fattening diets. At 60, 120 and 180 days of age, 6 lambs from each group were slaughtered to collect rumen content and tissue samples. Compared with ER lambs, the dry matter feed intakes of AR lambs increased (P<0.05) from 20 to 180 days of age, companying an increased average daily gain (ADG) from 61 to 120 days of age (P<0.05) and from 121 to 180 days of age (0.05<P<0.1). Although there was no difference in short-chain fatty acid (SCFA, including acetate, propionate, and butyrate) between treatments before weaning (P>0.05), it was higher (P<0.05) in AR lambs compared with ER lambs at the fattening stage. The rumen keratin layer of AR lambs was thinner (P<0.05) than that of ER lambs. Along with lamb growth from 60 to 180 days of age, the differences in rumen bacterial diversity between AR and ER treatments grew more distinct (P<0.05). Compared with ER lambs, AR lambs increased (P<0.05) rumen bacteria abundance, such as phylum Spirochaetes and genus Treponema at 60 days of age, phylum Actinobacteria and genus Succiniclasticum at 120 days of age, and phylum Proteobacteria at 180 days of age, but decreased genus Selenomonas from 60 to 180 days of age, and Anaerovibrio at 180 days of age. In summary, the early interventions before weaning could improve dry matter feed intake of lambs, which triggered robust rumen development and produced positive long-term effects on rumen fermentation and noticeable weight gain of fattening lambs. It suggests that the artificial rearing strategy is effective in improving rumen fermentation and microbial maturity of intensive fattening lambs.     

Effect of dioscorea opposite waste on growth performance,blood parameters,rumen fermentation and rumen bacterial community in weaned lambs

This study investigated the effects of dioscorea opposite waste (DOW) on the growth performance, blood parameters, rumen fermentation and rumen microbiota of weaned lambs. Sixty healthy weaned Small-Tailed Han lambs (male, (22.68±2.56) kg initially) were used as the experimental animals. Four levels of concentrate: 0 (control, CON), 10% (DOW1), 15% (DOW2) and 20% (DOW3), were replaced with DOW in the basal diet as experimental treatments. The results showed that lambs fed the DOW2 diet had a higher (P<0.05) dry matter intake (DMI) than the other groups. There was no significant difference (P>0.05) among DOW groups in average daily weight gain (ADG), and replacing concentrate with DOW linearly or quadratically increased (P<0.05) the ADG, while lambs fed the DOW2 diet showed greater (P<0.05) ADG than the CON group. The relative plasma concentration of growth hormone (GH), insulin like growth factor-1 (IGF-1) and insulin were affected by DOW, replacing concentrate with DOW linearly or quadratically (P<0.05) enhanced the plasma concentration of GH, IGF-1 and insulin, which was significantly higher (P<0.05) in the DOW2 group than in the CON, DOW1 and DOW3 groups. In addition, the DOW treatment showed a lower (P<0.05) concentration of blood urea nitrogen (BUN) than the CON group. Replacing concentrate with DOW quadratically decreased (P<0.05) the ruminal ammonia nitrogen (NH₃-N) and increased (P<0.05) the total of volatile fatty acids (TVFAs) at 0 and 4 h after feeding as well as linearly decreased (P<0.05) the NH₃-N at 8 h after feeding. Replacing concentrate with DOW linearly decreased (P<0.05) the propionate and increased the aceate before feeding, and linearly decreased (P<0.05) propionate and quadratically increased (P<0.05) the aceate at 4 and 8 h after feeding. Lambs fed the DOW2 diet increased the phylum Firmicutes and genera Succiniclasticum and Ruminococcus_1 groups, whereas decreased (P<0.05) the relative abundance of phylum Deferribacteres and genera intestinimonas and Ruminiclostridium. In summary, replacing the concentrate with 15% DOW was beneficial for improving the rumen fermentation and ADG by increasing the DMI and modulating the rumen microbial community.     

氧化三甲胺对南美白对虾生长、养分消化率和消化酶活性的影响

选用经基础日粮暂养1周后尾均初始体重为(1．01±0．05)g的健康南美白对虾为试验动物,以基 础日粮为对照组,在基础日粮中分别添加2,4,6和8 g／kg氧化三甲胺(TMAO)为试验组,每组均设3个重复,饲喂 8周,研究TMAO对南美白对虾生长、养分消化率和消化酶活性的影响。结果表明:(1)4,6和8 g／kgTMAO添加 组南美白对虾的终末平均体重和增重率显著高于对照组(P<0．05);2和4 g／kgTMAO添加组南美白对虾的饵料 系数显著低于对照组(P<0．05),而蛋白质效率显著高于对照组(P<0．05)。(2)添加4和6 g／kgTMAO均可显著 提高南美白对虾对干物质、粗蛋白和灰分的表观消化率(P<0．05)。(3)2,4和6 g／kgTMAO添加组南美白对虾的 肝胰脏蛋白酶、肝胰脏淀粉酶和肠道淀粉酶活性与对照组相比均显著提高(P<0．05);4和6 g／kgTMAO添加组南 美白对虾的肠道蛋白酶活性与对照组相比也显著提高(P<0．05);8 g／kg添加组仅肝胰脏蛋白酶活性与对照组相 比显著提高(P<0．05);添加TMAO对胃蛋白酶和肝胰脏脂肪酶活性无显著影响(P>0．05)。     

中成鱼阶段卵形鲳鲹对饲料蛋白质和脂肪的适宜需求量

通过添加不同浓度鱼粉,制成6组等脂等能的蛋白质梯度实验饲料(P1～P6),研究中成鱼阶段(初始体质量范围定义为100 g/只的个体)卵形鲳鲹对饲料中蛋白质的最适需求量。研究发现,随着饲料中蛋白质含量的升高(P1～P6),实验鱼的生长性能如增重率、蛋白质效率以及全鱼粗蛋白含量均呈现先显著升高(P0.05)而后逐渐平稳的趋势(P0.05),而饲料系数和摄食率呈现先显著降低(P0.05)而后轻微升高的趋势(P0.05)。折线回归模型拟合生长性能,计算中成鱼阶段卵形鲳鲹对饲料中蛋白质的最适需求量(质量分数)为49.75%。在获得蛋白质需求的基础上,通过添加不同水平的豆油,制成6组等氮的脂肪梯度实验饲料(L1～L6),研究中成鱼阶段卵形鲳鲹对饲料中脂肪的最适需求量。随着饲料中脂肪含量提高(L1～L6),卵形鲳鲹的增重率等生长性能呈现先显著升高后稳定的趋势(P0.05),而饲料系数和摄食率则呈现先显著降低后稳定的趋势(P0.05)。折线回归模型拟合生长性能,计算中成鱼阶段卵形鲳鲹对饲料中脂肪的最适需求量(质量分数)为12.20%～12.27%。     

配合饲料饲喂育成期水貂消化试验及饲养效果观测

将68只水貂按雌雄、体质量随机分为两组,分别饲喂常规鲜料(对照组)和配合饲料(试验组),在育成期进行饲养试验和消化试验。结果表明:母貂干物质和粗蛋白表观消化率对照组均高于试验组(P<0.05),公貂干物质和粗蛋白表观消化率对照组均显著高于试验组(P<0.01);试验组水貂干物质采食量和可消化干物质均略高于对照组;粗脂肪和粗纤维表观消化率试验组均高于对照组,差异极显著(P<0.01);对照组和试验组水貂能量表观消化率差异不显著(P>0.05);试验组水貂质量的增加均大于对照组。试验结果证实,采用配合饲料与一定比例的新鲜原料喂养水貂,是提高水貂生长性能、解决其饲料来源困难的比较合理的办法。