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1.
Heat stress in poultry is deleterious to productive performance. Chlorogenic acid (CGA) exerts antibacterial, anti-inflammatory, and antioxidant properties. This study was conducted to evaluate the effects of dietary supplemental CGA on the intestinal health and cecal microbiota composition of young hens challenged with acute heat stress. 100-day-old Hy-line brown pullets were randomly divided into four groups. The control group (C) and heat stress group (HS) received a basal diet. HS + CGA300 group and HS + CGA600 group received a basal diet supplemented with 300- and 600-mg/kg CGA, respectively, for 2 weeks before heat stress exposure. Pullets of HS, HS + CGA300, and HS + CGA600 group were exposed to 38°C for 4 h while the control group was maintained at 25°C. In this study, dietary CGA supplementation had effect on mitigate the decreased T-AOC and T-SOD activities and the increasing of IL-1β and TNFα induced by acute heat stress. Dietary supplementation with 600 mg/kg CGA had better effect on increasing the relative abundance of beneficial bacterial genera, such as Rikenellaceae RC9_gut_group, Ruminococcaceae UCG-005, and Christensenellaceae R-7_group, and deceasing bacteria genera involved in inflammation, such as Sutterella species. Therefore, CGA can ameliorate acute heat stress damage through suppressing inflammation and improved antioxidant capacity and cecal microbiota composition.  相似文献   
2.
采用免疫组化SP法研究了雌激素受体在lO日龄雏鸡脑组织内的表达,着重观察了雌激素受体在小脑、中脑、下丘脑及端脑的分布。研究表明,雌激素受体主要存在于细胞核中,少数区域仅存于胞浆或胞膜。雌激素受体在脑内分布广泛。在小脑中部皮质的颗粒层、蒲肯野氏层,中脑的中央白质、外侧丘系腹侧核、视束、后连合等区域,雌激素受体免疫反应产物为高密度;在小脑前部皮质的颗粒层,中脑中央灰质、尾侧线形核,端脑副高纹状体等区域,雌激素受体免疫反应产物为中等密度;小脑前部皮质的蒲肯野氏细胞,下丘脑视上核,端脑原始旧纹状体等区域,雌激素受体免疫反应产物为低密度。结果揭示,在鸡脑早期发育过程中,雌激素起著广泛而重要的作用。  相似文献   
3.
蛋雏鸡有效磷适宜水平的研究   总被引:1,自引:0,他引:1  
试验对0-6周龄蛋雏鸡日粮中有效磷(AP)的需要量进行了研究.选取1日龄罗曼蛋雏鸡360只,随机分为5个X理进行单因子试验,各处理设4个重复,每重复15只,试验期6周.对以玉米豆粕为基础的日粮设计0.65%-0.25%之间5个处理的有效磷水平.通过对不同处理雏鸡的体增重、料重比、胫骨质量和粪磷的排泄量等数据进行分析,当有效磷水平为0.35%和0.45%时,可获得最好的体增重和料重比,两个处理间差异不显著(P>0.05);0.25%低水平处理组体增重低于0.35%(P>0.05),也低于0.45%(P<0.05),但均显著高于高水平(0.55%-0.65%)的处理组(P<0.05).料重比以0.35%的处理组为最高,达2.60±0.11.骨骼质量和血液指标各处理间差异不明显.粪磷的排泄量随日粮中育效磷水平升高而增加,0.25%和0.35%处理组比0.65%处理组磷排泄量分别减少26.67%和22.51%(P<0.05).以上结果提示,以玉米豆粕为基础的日粮中有效磷水平为0.35%时不仅可以获得理想的生产性能,而且有利于对环境的保护.  相似文献   
4.
生长期能量采食水平对生长蛋鸡的影响   总被引:2,自引:0,他引:2  
试验用432只伊莎褐商品蛋鸡,研究了三个不同能量采食水平日粮对生长、性成熟的影响。试验得出在7-9,10-12,13-15,16-18周内,高能量采食水平组鸡比中、低能量采食水平组鸡的日增重高2.52%、5.43%(P〈0.05),,3.33%、16.59%(P〈0.01),8.1%、12.9%(P〈0.01),23.6%、45.1%(P〈0.01),各期日增重差异显著;饲料转化效率在7-9周高能  相似文献   
5.
6.
Phosphorus runoff from the land application of poultry litter has become a concern in watersheds in the Ozark Plateau region, prompting local growers to use alternative litter management practices. One option is the export of excess poultry litter from producers in nutrient-surplus watersheds to users located in areas where nutrient loads are not problematic. In 2006, nearly 100,000 tons of broiler and turkey litter was exported by BMPs Inc., a nonprofit corporation providing litter management services. However, breeder hen litter and pullet litter are rarely exported because there are limited outlets for these lower nutrient value litters. Another poultry industry by-product is eggshell waste from egg-breaking operations, most of which is currently landfilled at a cost of $25/ton. Composting was examined as an alternative method to convert litter and eggshell wastes into a marketable soil amendment, making use of the beneficial soil nutrients available in both; 4 blends and 2 production systems were analyzed. Process results indicated that during composting, the observed temperatures of each of the 4 blends were different, but all followed a similar trend throughout the production cycle. Functional group inventory and diversity analysis indicated that all blends fell within optimal ranges of microbial species, except for the ratio of aerobic to anaerobic bacteria; only blend 4 was within the optimal value for this parameter. Diversity values for each blend fell within the moderate diversity range (3 < d < 6.5). Maturity analysis results indicated that no blends were mature at 11 wk (index <50%) and could not safely be used in horticultural applications but could safely be used in field applications. Break-even analyses indicated that compost could be produced at an average cost (across the 4 blends) of $17.48 to $20.09/ton for systems 1 (small-scale) and 2 (large-scale), respectively.  相似文献   
7.
8.
以1800只海兰雏鸡为试验材料,培育于青年鸡场;从130日龄起易地饲养于新安县某产蛋鸡饲养专业户,同时由青年鸡场一体的饲料厂供应源于同一套配方的配合饲料.结果表明,青年鸡与产蛋鸡易地专业化饲养切实可行.青年鸡亚系统,130日龄鸡的体重略高于标准,每只鸡的饲料成本为13.8元,盈利5.5元.产蛋鸡亚系统,91%以上的产蛋率维持12周,料蛋比2.7:1;90%以上的产蛋率期间,千只鸡的日盈利为141.8元.  相似文献   
9.
Bovans White Leghorn pullets were utilized to evaluate the use of an enzyme cocktail from 0 to 126 d of age. Dietary treatments varied in CP, ME, and enzyme (EZ) supplementation. Feed intake, BW gain, and feed conversion ratio data were gathered in addition to determining nutrient retention and digestibility during the trial. Cumulatively, feed consumption was decreased by EZ supplementation when added to a required ME diet. Body weight gains were similar across dietary treatments; however, cumulative feed conversion ratio was significantly improved with EZ supplementation. Interactions regarding nutrient retention and digestibility were numerous. Similar responses were noted for energy and protein retention values during the trial with changes in response to dietary treatments as the pullets aged. Compared with feeding an industry applicable diet (required ME/CP without EZ − $0.27/lb gain), all dietary treatments reduced production costs with significant reductions when reducing CP. Lowest feed cost ($)/lb gain and percent excreta N was feeding pullets a diet with reduced ME and CP supplemented with EZ ($0.262/lb gain; 5.19% N). Possible further reductions in ME or dietary CP, or both, with EZ supplementation may prove to be even more economical and environmentally friendly.  相似文献   
10.
固始鸡G2系母鸡8、18周龄体重与开产体重的相关性分析   总被引:1,自引:0,他引:1  
通过对550只固始鸡G2系母鸡8周龄、18周龄及开产体重的分析,结果发现:8周龄体重与18周龄体重、8周龄体重与开产体重以及18周龄体重与开产体重之间均存在着中等以上强度的相关关系,其相关系数分别为0.5583,0.3916,0.6776。在此基础上,建立了两个周龄与体重之间的直线回归方程,为固始鸡的育种工作提供了参考依据。  相似文献   
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