日粮中添加青绿饲料对土种鸡生产性能的影响

研究了土种难日粮中添加青绿饲料对其生产性能的影响。试验应用30日土种鸡12000只,随机地分成6组,每组2000只。青绿饲料为田间收割获得,主要成分为紫云英、野豌豆和芷蓿等。通过切碎按0％,5％,10％,15％,20％和25％添加量替代基础日粮直接饲喂,试验期为50d。结果表明在80日龄上市是试验组土种鸡随着青绿饲料添加量的增加只平均体重略低,但与安全饲喂精料的对照组土种鸡比较,差异不显著。10％和15％添加量组量佳,平均较对照组鸡省料225.3g／只,降低饲料成本显著,经济效益大。本试验结果表明30－80日龄土种鸡日粮中添加于绿饲料是可行的,尤其是10％－15％添加量为最佳。     

蛋种鸡生产中应用植酸酶的效果试验

随着畜牧业的迅猛发展 ,畜牧场排放的废弃物对环境的污染越来越严重 ,尤其是粪便中的高磷对水源的污染危害更大。而用植酸酶来对植物饲料本身所含的植酸磷进行分解 ,以减少磷酸氢钙在饲料中的添加 ,则既可降低饲料成本 ,提高生产性能 ,又可减轻鸡粪中氮、磷的排出量 ,减少对环境的污染 ;同时也可防止或减轻因使用较多磷酸氢钙可能出现的因高氟而造成的种鸡体质衰弱 ,产蛋量下降 ,蛋壳变脆及孵化率下降的问题。为此 ,我们做了植酸酶在蛋种鸡生产中的应用实验。1　材料和方法1 1　植酸酶　　采用德国ＢＡＳＦ公司产品 ,商品名为酶他富 5 0 0 0…     

日粮添加不同水平的蛋氨酸对山鸡产蛋高峰期生产性能的影响

试验选取46~48周龄,健康无病,体型、体重基本一致的产蛋高峰期山鸡200只,随机分为5组,1个对照组,4个试验组(Ⅰ、Ⅱ、Ⅲ、Ⅳ组),每组设10个重复,每个重复4只山鸡。每组基础日粮相同(蛋氨酸质量分数为0.22%),各组蛋氨酸添加水平分别为0%、0.05%、0.10%、0.15%和0.20%,试验期2个月。结果表明,日粮中添加适量蛋氨酸不仅维持较长时间的产蛋高峰期和理想的产蛋峰值,显著地提高产蛋量和平均蛋重,而且还能提高饲料报酬和经济效益。     

夏季产蛋鸡日粮中添加动物脂肪对提高产蛋性能的效果

夏季 ,产蛋鸡日粮中添喂动物脂肪的试验组 ,与不添喂的对照组 ,两组产蛋率分别为 85 .7%和 79.2 % ,两组差异显著 (P <0 .0 5 ) ;平均蛋重分别为 6 2 .44± 1.13g和 6 2 .2 7± 1.32g ,两组差异不显著 (P >0 .0 5 ) ;料蛋比两组分别为 2 .5 1∶1和 2 .6 8∶1,两组差异显著 (P <0 .0 5 ) ;经济效益试验组比对照组提高 9.6 %。     

小麦基础日粮添加木聚糖酶对蛋鸡生产性能的影响

选用 30 0 0羽 4 0周龄依莎褐壳蛋鸡 ,随机分成 2组 ,分别设为对照组和试验组。每组 3个重复 ,每个重复 5 0 0羽。对照组饲喂基础日粮 ,试验组在对照组基础上添加 0 .1%的木聚糖酶。研究结果表明 ,试验组与对照组相比 ,平均产蛋率提高6 .17% (P <0 .0 1) ,平均蛋重提高 5 .2 4 % (P <0 .0 1) ,料蛋比降低 11.3% (P <0 .0 1) ,差异均达到极显著水平。     

用发酵血粉代替进口鱼粉对蛋种鸡的影响

本文介绍了选用京白823父母代23周龄后备鸡,用单因子有重复对比试验设计。在种鸡饲料中以发酵血粉代替同等蛋白量的进口鱼粉,结果表明:其生产性能显著低于进口鱼粉组。43周龄产蛋率低2.4%,产蛋教少3.39枚(P<0.01);而采食量,饲料消耗比,孵化率组间无显著差异(P>0.05)。在鱼粉资源短缺和昂贵的条件下,利用部分发酵血粉,可以节省饲料成本,而对生产影响较小。     

日粮添加虾青素对蛋鸡产蛋性能的影响

通过在基础日粮中添加虾青素研究其对蛋鸡产蛋性能的影响,为虾青素在蛋鸡生产中应用提供依据。试验选用3 000只200日龄海兰褐蛋鸡,随机分成对照组(基础日粮组)和试验组(基础日粮中添加万分之一的虾青素),每组15个重复,每个重复100只,预试期14d,试验期51d。结果显示:添加虾青素试验组蛋鸡产蛋率显著高于对照组(P0.05),说明虾青素具有提高蛋鸡产蛋性能的作用。     

枯草芽孢杆菌对草鱼生长性能的影响

研究了枯草芽孢杆菌对草鱼生长性能的影响,试验组饲喂添加1 000、1 500、2 000、2 500 mg/kg枯草芽孢杆菌的试验饲料,经过70天的池塘网箱养殖试验,结果表明:与基础饲料对照组相比,添加枯草芽孢杆菌能够提高草鱼的特定生长率,降低饵料系数,其中2 000 mg/kg组与对照组相比差异显著.除2 500 mg/kg组外,其余试验组蛋白质沉积率均高于对照组,脂肪沉积率均显著高于对照组,尤以2 000 mg/kg组蛋白质、脂肪沉积率最高.     

枯草芽孢杆菌对肥育猪生产性能和经济效益的影响

试验选用杜长大三元杂交50kg左右健康猪368头,根据体重随机分为4组,每组4个重复。对照组饲喂玉米-豆粕型基础饲粮,试验组在玉米-豆粕型饲粮基础上添加枯草芽孢杆菌100、200、300g/t。结果表明,与对照组相比,饲粮中添加300g/t枯草芽孢杆菌显著地提高了肥育猪饲料转化率(P0.05),降低料肉比5.3%,并且其个体重达到最大。添加枯草芽孢杆菌对肥育猪消化道疾病有改善,随着添加水平的增加消化道药物使用逐渐减少,与对照组相比,300g/t枯草芽孢杆菌组消化道药物使用最少。从经济效益上分析,与对照组相比,每吨饲粮添加300g枯草芽孢杆菌可以使每头猪多获益43元。由此可见,饲粮中添加300g/t枯草芽孢杆菌可以提高肥育猪生产性能和经济效益。     

Effect of probiotic (Lactobacillus sporogenes) feeding on egg production and quality,yolk cholesterol and humoral immune response of White Leghorn layer breeders

The effect of probiotic (Lactobacillus sporogenes) feeding on egg production and quality, yolk cholesterol and humoral immune response of White Leghorn (WL) layer breeders was studied. WL layer breeders (24 weeks) were randomly distributed into three groups of 28 each and were housed in individual California type cages. Considering one bird (individual feeding) as a replicate, 28 such replicates were randomly allotted to one of the three dietary treatments: basal (control) or basal with probiotic supplementation at a rate of 100 or 150 mg kg^?1 feed. The probiotic used in the study was a commercial preparation containing L. sporogenes with 6000 million spores g^?1 of the product. Dietary supplementation of L. sporogenes at 100 mg (6 × 10⁸ spore) kg^?1 diet significantly increased egg production and feed efficiency. However, body weight gain, feed intake, egg weight, specific gravity and Haugh unit was not influenced by probiotic feeding. The eggshell breaking strength, shell weight and shell thickness increased significantly by feeding 100 mg probiotic kg^?1 diet. The serum concentration of calcium and protein increased, and that of cholesterol decreased by L. sporogenes supplementation. The yolk cholesterol followed the same trend of serum cholesterol. Feeding of L. sporogenes significantly enhanced antibody production. No difference in antibody production could, however, noticed between the levels (100 or 150 mg) of probiotic. It is concluded that feeding of L. sporogenes at 100 mg (6 × 10⁸ spore) kg^?1 diet significantly enhanced the egg production, shell quality and humoral immune response of WL layer breeders during 25–40 weeks of age. Copyright © 2007 Society of Chemical Industry     

留兰香茎叶粉对肉兔生长性能和屠宰性状的影响

在肉兔饲料里用5%、10%和15%留兰香茎叶粉替代相应苜蓿草粉探讨留兰香茎叶粉对肉兔生长性能和屠宰性状的影响。结果表明:与对照组相比,5%留兰香茎叶粉组和10%留兰香茎叶粉组平均日采食量、平均日增重有改善向好的趋势(P>0.05),15%留兰香茎叶粉组平均日增重显著降低(P<0.05),3个组全净膛重、半净膛重、全净膛率和半净膛率均有提高的趋势(P>0.05)。添加10%留兰香茎叶粉替代苜宿草粉效果较好。     

益生素对肉仔鸡生长性能及免疫器官发育的影响

研究益生素对AA肉仔鸡的生长性能及免疫器官发育的影响.对照组饲喂玉米-豆粕型基础日粮,抗生素组在基础日粮中添加50mg/kg金霉素,Ⅰ、Ⅱ组分别添加200、400mg/kg益生素.结果显示:21日龄Ⅰ、Ⅱ组平均日采食量较对照组分别降低1.4％和1.9％,料重比分别降低6.7％和6.7％;Ⅰ组法氏囊重和法氏囊指数分别提高35.4％和36.9％,Ⅱ组胸腺重和胸腺指数分别提高4.5％、9.5％.42日龄Ⅰ、Ⅱ组平均日采食量较对照组分别提高9.9％和3.7％,料重比分别降低1.4％和2.3％;对照组脾脏指数略高于Ⅰ组,显著高于Ⅱ组;Ⅰ、Ⅱ组胸腺重、胸腺指数及法氏囊指数均显著高于对照组.21日龄Ⅰ、Ⅱ组平均日采食量较抗生素组分别提高0.9％和0.4％,料重比分别降低3.1％和3.1％;42日龄Ⅰ、Ⅱ组平均日采食量分别提高5.7％和3.7％,料重比分别降低1.9％和2.8％.以添加水平200 mg/kg的效果较好.     

Effects of enzymes in diets with varying energy levels on growth and egg production performance of Japanese quail

The present study was conducted to evaluate the effect of feed‐grade enzyme supplementation in diets with varying levels of energy on the performance of growing and laying Japanese quails. Day‐old Japanese quails, 504 in number, were subjected to six dietary treatments with six replicates at each treatment. Each replicate had 14 chicks. The dietary treatments consisted of three energy levels ie 12.15 MJ (2900 kcal), 11.30 MJ (2700 kcal) and 10.48 MJ (2500 kcal) ME kg^?1 diet and two enzyme levels (0 and 0.5 g kg^?1 diet). A metabolism trial was conducted at the fourth week of age. At the end of week 5, 10 quails (five of each sex) per treatment were sacrificed for carcass characteristics and 20 female quails from each of the six dietary groups were housed in individual laying cages and fed respective layer diet to study the laying performance and egg quality up to 20 weeks of age. Body weight gains of quails fed 12.15 MJ or 11.30 MJ ME kg^?1 diets were significantly higher (p < 0.01) than those fed diets with 10.46 MJ ME kg^?1 diet. Feed intake was significantly lower (p < 0.01) in birds that received diet with 12.15 MJ ME kg^?1 than in birds that diets containing either 11.30 or 10.46 MJ ME kg^?1 diet. Feed conversion ratio (p < 0.01) was best at 12.15, followed by 11.30 and 10.46 MJ ME kg^?1 diet. Enzyme supplementation did not improve the growth performance, feed intake or feed conversion efficiency of quails. Enzyme addition also did not influence nitrogen retention or energy or dry matter metabolizability. The carcass characteristics did not differ because of energy or enzyme supplementation. Feed intake increased significantly (p < 0.01) as the dietary energy level decreased. The egg production and quality characteristics remained almost similar in all the dietary treatments. It was concluded that the optimum dietary energy level for quail was 12.15 MJ (2900 kcal) ME kg^?1 during the growing phase and 11.30 MJ (2700 kcal) ME kg^?1 during the laying phase. Addition of feed enzymes to conventional diets containing varying levels of maize, soyabean meal, fish meal and deoiled rice bran was not beneficial to improve growth, carcass traits, egg production performance or nutrient utilization. Copyright © 2004 Society of Chemical Industry     

Effects of chop length of alfalfa and corn silage on milk production and rumen fermentation of dairy cows

Effects of chop length (shorter = 10 mm or longer = 19 mm) of alfalfa silage and corn silage were determined in 16 midlactation Holstein cows using a 4 × 4 Latin square design with a 2 × 2 arrangement of treatments. Experimental periods were 21 d long and consisted of 14 d of adaptation and 7 d of sampling. Cows received total mixed ration containing (dry matter basis) 44.0% barley grain-based energy supplement, 12.6% protein supplement, and 21.7% longer chop or shorter chop alfalfa silage and 21.7% longer chop or shorter chop corn silage. Reducing the chop length of alfalfa silage and corn silage reduced the average geometric particle length from 14.4 to 11.0 mm and from 14.2 to 10.4 mm, respectively. Reducing the chop length of both silages reduced the proportion of the diets retained by the 8-and 19-mm screen of the Penn State Particle Separator from 55.0 to 46.0% of dry matter. Reducing the alfalfa chop length increased total rumen volatile fatty acids at 4 to 5 h after feeding but did not affect rumen pH at 4 to 5 h after feeding, feed intake, and milk production. Reducing the corn silage chop length increased dry matter intake from 22.3 to 23.2 kg/d, increased rumen pH at 4 to 5 h after feeding from 6.12 to 6.20, but did not alter rumen volatile fatty acids at 4 to 5 h after feeding or milk production. Daily milk yield, milk fat percentage, and milk protein percentage averaged 38.2 kg/d, 2.62%, and 3.29%, respectively, across all diets. The low milk fat percentages suggest that all diets induced subacute ruminal acidosis (SARA), whereas the rumen pH did not indicate SARA. This discrepancy could be due to a difference in the time of rumen pH measurement and the time of the lowest rumen pH. Hence, the pH data need to be interpreted with caution. Diets could have induced SARA, because for all experimental diets the content of forage neutral detergent fiber was lower than recommended for barley grain-based diets.     

抗热应激剂对獭兔生产性能和营养消化率的影响

研究0.5％抗热应激剂1号(主要成分VC、VA、VE)、0.5％抗热应激剂2号(主要成分碳酸氢钠、氯化钾等电解质)和1.0％抗热应激剂3号(主要成分生石膏、金银花、黄芩、藿香、党参、苍术、甘草等12味中草药粉碎后按一定比例混合配制),这3种不同的抗热应激剂在夏季高温环境对3月龄健康、体重相近的獭兔的生长性能和营养消化率等指标的影响.结果表明:在高温季节獭兔日粮中添加抗热应激剂,试验组与对照组相比平均日采食量、平均日增重分别提高1.52％～7.94％、5.87％～17.75％,料重比降低4.27％～9.33％,成活率提高3.56％～7.15％,粗蛋白质、粗脂肪、粗纤维、钙和磷的消化率分别提高2.30％～6.24％、1.16％～3.26％、2.40～9.13％、3.58％～5.03％和2.05％～8.61％.以抗热应激剂2号效果较佳.     

Effects of compound probiotics on growth performance,rumen fermentation,blood parameters,and health status of neonatal Holstein calves

This study aimed to investigate the effects of compound probiotics (consisting of 10⁸ cfu/g of Lactobacillus plantarum, 10⁸ cfu/g of Pediococcus acidilactici, 10⁸ cfu/g of Pediococcus pentosaceus, 10⁷ cfu/g of and Bacillus subtilis) on growth performance, rumen fermentation, bacteria community, blood parameters, and health status of Holstein calves at the first 3 mo of age. Forty-eight newborn calves were randomly divided into the following 3 groups: control group (milk replacer with no compound probiotics), low compound probiotics group (milk replacer + 0.12 g of compound probiotics per head per day), and high compound probiotics group (HP; milk replacer + 1.2 g of compound probiotics per head per day). Starter pellets of the low compound probiotics and HP groups were coated with 0.05% compound probiotics. Milk replacer was provided from 2 to 63 d of age (6 L at 2–10 d, 8 L at 11–42 d, 6 L at 43–49 d, 4 L at 50–56 d, and 2 L at 57–63 d), and starter pellets were provided ad libitum from 7 to 90 d of age. Body weight and body size (d 1, 30, 60, and 90), blood (d 40 and 80), and rumen fluid (d 90) were analyzed using the one-way ANOVA procedure; fecal score was recorded daily and analyzed as repeated measures using the mixed model procedure. Results showed that diet supplemented with compound probiotics had no effects on the body weight, average daily gain, dry matter intake, and feed efficiency. At 90 d of age, diet supplemented with compound probiotics decreased the withers height. Immunity activities increased in the HP group, supported by the increased concentrations of serum total protein and immunoglobulins at 40 d of age, and by the increased activity of superoxide dismutase at 80 d of age. Diet supplemented with compound probiotics altered rumen fermentation, indicated by the decreased rumen acetic acid and propionic acid, and the increased butyric acid concentrations. Diet supplemented with compound probiotics improved the health status of calves, indicated by the decreased fecal score at 3 wk of age and the decreased medicine treatments. In summary, although diet supplemented with HP decreased the withers height, this level of probiotics is recommended to improve rumen development and health status of newborn Holstein calves.     

枯草芽孢杆菌发酵棉籽粕对黄羽肉鸡营养物质代谢率、生产性能的影响

研究在1日龄黄羽肉鸡日粮中分别添加0％、2％、5％和8％的枯草芽孢杆菌发酵的棉籽粕对黄羽肉鸡的生产性能、消化代谢率的影响。结果表明：与未添加发酵棉籽粕组相比,添加棉籽粕组黄羽肉鸡的粗蛋白质、钙和磷的表观代谢率提高显著,且8％添加组代谢率最高;粗脂肪的代谢率降低显著,平均日增重和饲料转化率提高显著,且5％添加组平均日增重和饲料转化率最高。枯草芽孢杆菌发酵棉籽粕适宜添加量为5％。     

Effects of an acute feed restriction at the onset of the seasonal breeding period on reproductive performance and milk production in pasture-grazed dairy cows

Reproduction and milk production responses were compared between dairy cows offered a high (HPA; n = 453 in 4 replicates) or low (LPA; n = 317 in 3 replicates) pasture allowance for the first 14 d after the planned start of mating (d 0 of experiment) in 2 seasonal, pasture-based dairy herds. Estimated pasture dry matter intake (DMI) between d −1 and 13 were 14.3 ± 2.8 and 8.0 ± 1.7 kg of DM/cow per day for HPA and LPA cows, respectively. The LPA cows produced 22% less energy-corrected milk during the 14-d feeding treatment period, and milk yield remained less in LPA cows at d 53 despite all cows receiving pasture allowances to support DMI of 16 kg of dry matter/cow per day from d 14 onwards. The 3-wk submission rate (percentage of cows inseminated at least once from d 0 to 20) and the 3- and 6-wk pregnancy rates of LPA cows (88, 45, and 71%, respectively) were lower than those of HPA cows (94, 53, and 78%, respectively), but conception rates to first (50%) or second (47%) service and final pregnancy rates (93%) did not differ between treatments. These results quantify the immediate and subsequent responses in reproductive performance and milk production to a severe restriction in DMI at the onset of a seasonal breeding period in pasture-grazed dairy cows.