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951.
JI Xiang-bo YAO Guo-jia LIU Jian CHEN Li-dun LI Xin-zheng YANG Jian-ping ZANG Yan-quan 《中国畜牧兽医》2015,42(10):2669-2675
This experiment was conducted to investigate the effect of soybean meal replaced by brewer's grain (BSG) or fermented brewer's grain (FBSG) on growth performance,immune organ index and intestinal flora of meat geese.A total of 250 geese at 28 days of age were randomly assigned to 5 groups with 5 replicates per group and 10 geese per replicate.The geese in control group were fed a basal diet (with soybean);The geese in groups 1 and 2 were fed the basal diet with the 10% and 20% BSG replacing the soybean,respectively;The geese in groups 3 and 4 were fed the basal diet with the 10% and 20% FBSG replacing the soybean,respectively.The whole experiment period was 42 days,including three phases:15 d (early stage),14 d (middle stage) and 14 d (later stage).The results showed as follows:①From the whole experiment period,compared with control group,the ADG of geese in group 1 was significantly increased (P<0.05),the ADG and ADFI of geese in group 4 were significantly decreased (P<0.05),there were no obvious change in growth performance of geese in groups 2 and 3 (P>0.05).② Compared with control group,the thymus index and spleen index of geese in groups 1,2 and 3 were extremely significantly increased at early stage (P<0.01);At middle and later stages,the spleen index of geese in group 2 were significantly and extremely significantly increased (P<0.05;P<0.01);There were no significant differences in bursa of fabricius index of geese among all groups (P>0.05).③ Compared with control group,the number of Escherichia coli and Salmonella in cecum in groups 1 and 2 were extremely significantly decreased at early and later stages (P<0.01),while the number of Bifidobacteria and Lactobacillus were increased in different degrees;the number of Bifidobacteria and Lactobacillus in cecum in groups 3 and 4 were extremely significantly increased at later stage (P<0.01).In conclusion,10% BSG replacing soybean in the basal diet could improve the growth performance and intestinal flora of meat geese;10% FBSG replacing soybean in the basal diet could promote the growth of beneficial bacteria of meat geese,but had no effect on growth performance;While 20% replacing soybean in the basal diet could decrease the feed intake and weight gain of meat geese,hinder its growth and development. 相似文献
952.
LU Xin-xing YANG Jin-li WANG Hai-rong WANG Gui-chao GAO Ai-wu ZHANG Li-min HOU Xian-zhi 《中国畜牧兽医》2015,42(12):3202-3209
To study the effect of nutrient restriction and compensation on weight,serum indexes and gene expression of chest fat adipokine in Mongolian lamb,thirty male lambs were randomly divided into control group (20.26 kg± 3.63 kg) and feed restricted group (21.29 kg±3.00 kg).The experiment lasted for 120 days,including 60 days for feed restriction and 60 days for compensatory feed.At the end of each stage,five lambs from each group were slaughtered and chest fat was collected.Serum concentration of triglycerides,non-esterified fatty acids (NEFA),total cholesterol were measured.Quantitative Real-time PCR were used to determine Adiponectin,Visfatin,PPAR-γ and ACC genes expression.The results showed that:①The lamb body weight of restricted group kept maintain level and that of control group showed a increase tendency.During the compensatory period,the average daily gain (ADG) of restricted group was significantly higher than control group (P< 0.05).②During the restriction period,serum triglycerides concentration of lambs in restricted group was significantly decreased at day 30 and 60 (P< 0.05),and NEFA concentration was significantly increased at day 30 (P< 0.05).After 60 days of nutritional compensation,all serum parameters we tested were not significantly different between restrict group and control group (P >0.05).③During the restriction period,PPAR-γ and ACC gene expression in restricted group were significantly lower than that of control group (P< 0.05),while no significant differences were found during the compensation period (P>0.05).Adiponectin and Visfatin genes expression in chest fat was not significantly changed throughout the experiment (P >0.05).We could know that nutritional restriction reduced fatty acid synthesis and adipocyte differentiation ability,adipose tissue was mobilized energy metabolism,and total cholesterol was recoveried growth on the compensation.However,the ACC and PPAR-γ genes in restricted group were significantly decreased with the body weight increased rapidly during the compensatory stage.Adiponectin and Visfatin were not significantly different between restricted and compensatory stages. 相似文献
953.
To determine the apparent digestibility of cassava residue (CR) nutrient and the effects of CR on growth performance when replaced the different levels corn in diet,two experiments were designed.In the first experiment,8 Duroc×Landrace×Yorkshire crossbred barrow pigs with the similar weight (22.46 kg±1.08 kg) were chosen for determining the apparent digestibility of CR.The pre-test period lasted for 10 days,and the trial period lasted for 5 days.In the second experiment,160 Duroc×Landrace×Yorkshire crossbred pigs with the similar weight(21.09 kg±0.72 kg) were randomly divided into five groups with four replicates per group and eight pigs per replicate.The control group was fed with basal diet while the experimental groups were fed diets containing 5%,10%,15% and 20% levels of substitution of corn by CR,respectively.The pre-test period lasted for 5 days,and the trial period lasted for 30 days.The results showed that the content of CP and EE in CR were 2.73% and 0.68%,but CF and total energy were 15.34% and 13.55 MJ/kg.The content of Lys and Thr were 0.11% and 0.08%,respectively.Calcium and phosphorus apparent digestibility were low,just only 40.24% and 34.76%,respectively,while apparent total energy digestibility was 65.62%.The apparent digestibility of Arg,Glu,Tyr,Met,Leu and Val were higher than 80%.The average daily gain was reduced with increasing dose of CR,which the group of 15% and 20% addition were significantly lower than that of control group (P< 0.05).However,the average daily gain of 5% and 10% groups were no significant difference with the control group(P >0.05).The feed cost of 5% and 10% addition groups were decreased by 0.01 and 0.05 yuan.In conclusion,under this experimental condition,the appropriate addition of CR for growing-fishing pig (20 to 50 kg ) was 5% to 10% in the diet. 相似文献
954.
955.
沙漠地区樟子松生长的多元统计分析及影响因子研究 总被引:4,自引:0,他引:4
应用SPSS统计软件包分析引种多年的樟子松的生长 ,对沙漠地区樟子松的生长规律及影响因子进行研究 ,并对所建立的多种生长模型进行对比分析 ,认为模型Y=e( 7.38- 16 .6 4/t) (R2 =0 .9990 6 )能够精确地反映樟子松的高生长规律。樟子松生长规律周期性强 ,即每年 4月至 6月为高生长期 ,4月至 9月为胸径生长期 ,其生长趋势由缓慢到快速 ,然后减缓。连年生长具有较强规律性 ,1~ 5龄生长较为缓慢 ,6龄以后进入生长旺期。影响樟子松生长的气候因素主要分为三类 ,即温度、水分和日照 ,其中温度和水分是主导因子。 相似文献
956.
根据湖南省福寿国有林场杉木生态公益林(幼龄林、中龄林、近熟林)复测数据,通过研究Hegyi,V_Hegyi,W_V_Hegyi三种竞争指数与胸径的相关性,选择相关性最强的W_V_Hegyi竞争指数,构建单木竞争生长模型。以此为基础,用加权平均树高作为胸径生长量的权重,重新构建了单木竞争生长模型,并对W_V_Hegyi竞争指数分布规律进行分析,利用回归分析方法构建径阶竞争指数预估模型和径阶生长模型。通过基于加权胸径生长量与W_V_Hegyi竞争指数构建径阶生长模型,以期为林木从单木到林分的模拟提供新途径。 相似文献
957.
以引自甘肃省小陇山林业科学研究所的15个丽江云杉家系3年生苗为材料,于国有樟村坪林场造林,观测各家系的成活率、保存率、树高、当年新梢长、地径、南北平均冠幅和一级分枝数,并对家系间6个生长性状指标进行分析。结果表明:7年生时,15个丽江云杉家系间保存率和新稍长的差异均不显著,树高和冠幅的差异均达极显著,地径和一级分枝数的差异均达显著。综合选择出的3个优良家系7年生平均树高比其它12个家系的平均树高提高16.5%,当年新稍长提高10.9%,地径提高4.6%,冠幅提高10.9%,保存率提高3.4%。 相似文献
958.
通过对绿色植物生长调节剂GGR8号在寒富苹果栽培上的应用进行的试验研究,结果表明:GGR8能够提高寒富苹果的品质,20、40、60 mg·kg-1等3种施用浓度在新梢生长量、含糖量、硬度方面均比对照有所提高,尤以60 mg·kg-1的施用浓度应用效果最好,其新梢生长量达到了36.7 cm,比对照增加9.3 cm;单果质量达到了240 g,比对照增加了95 g;含糖量达到了15%,比对照提高3个百分点;硬度达到了9.5 kg·cm-2,比对照增加了1.1 kg·cm-2。 相似文献
959.
以蒙古栎种子为材料,研究播种时期对蒙古栎不同类型苗木出苗和生长的影响,结果表明:蒙古栎在秋季不同时间播种的出苗率均在60%以上,但以早期(9月下旬)播种的出苗率最高(大于80%),早期播种的苗木在苗高、地径、侧根数、根体积和根生物量等指标上都明显要高于其它播种时期,蒙古栎在秋播裸根育苗时应适时早播;秋季播种的容器苗在所有观测的形态指标上均好于春季播种的容器苗,秋季容器育苗质量更高。 相似文献
960.