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11.
The nitrogen (N) fertilizer effect of layer hen and broiler manure applied at different times on spring barley yield was studied in seven Swedish field experiments during 2005–2008. Two experiments had parallel field incubations to study N release after fertilizer application. The effect of total N in manure on N offtake was 30–40% that of mineral N, except in a dry year, when the effect was very low. Although the relative proportions of ammonium N, uric acid N and other N differed between the hen and broiler manure, the effect of total N was similar for both. In field incubations, mineral N decreased from 75 to 60% of total N applied in hen manure, whereas it increased from 20 to 50% in broiler manure, because of net immobilization and release, respectively. The limited fertilizer nitrogen replacement value, corresponding to only 30–40% of total N, could be as a result of ammonia volatilization after rather shallow incorporation with harrow. Net N release from broiler manure lasted for 6–8 weeks after application, after which it generally ceased. In some cases, manure application in early spring gave better yield effects than application at sowing, probably because of better synchronization of the N release with crop N requirements. The residual N effect on the N offtake in crop in the year after manure application was on average 3% of the total N applied, equivalent to a fertilizer replacement value of about 6%.  相似文献   
12.
Effect of extended storage on egg quality, embryo mortality and hatchability in FUNAAB-ɑ chickens was determined. Hatchable eggs (n = 288; weighing 53.2 ± 4.67 g) collected from a flock of FUNAAB-ɑ layer breeder hens aged 32 weeks were stored in egg tray with broad end up under 16 ± 1.5°C for either 0, 4, 8, 12, 16 or 20 d. Before incubation, eight eggs from each group were evaluated for internal and external quality traits. Remaining eggs were set in an incubator and transferred into hatcher on embryonic day 18. Data collected were subjected to one-way analysis of variance. Egg weight loss (EWL; p < .001), surface area (p < .001), yolk diameter (p < .001), inner and outer blastoderm diameters (p < .05) and dead in germ (DIG; p < .001) increased with storage duration while yolk height (p < .001), yolk index (p < .001), albumen weight (p < .05), albumen height (p < .05), albumen index (p < .01), Haugh's unit (HU; p < .05), fertility (p < .001), hatchability of set (HATCHS; p < .001) and fertile eggs (p < .05) decreased. Weight losses of 0, 1.2, 2.2, 3.4, 4.6 and 6.1% were recorded in egg stored for 0, 4, 8, 12, 16 and 20 days respectively. Eggs stored beyond 8 days exhibited higher DIG and lower HATCHS. Shell percentage in 4 days storage (11.4%) was lower (p < .05) than in 16 days storage (13.4%). Shell thickness was similar in eggs stored for 0 to 12 days, but 8 days storage (0.60 mm) had thinner (p < .01) shell than day 16 (0.71 mm) and day 20 (0.73 mm) storage. Internal quality unit (IQU) was higher (p < .05) in fresh eggs (180.4) than in 12 days (167.8) and 20 days (167.8) stored eggs. Extended storage of FUNAAB-ɑ eggs caused EWL, surface area shrinkage, lowered HU and IQU, loss of yolk and albumen quality, increased blastoderm diameters and DIG, and decreased egg fertility and HATCHS from day 8 forward. Storing FUNAAB-ɑ eggs beyond 8 days reduced quality parameters; therefore, other mitigating factors are recommended when storing beyond 8 days.  相似文献   
13.
The objective of this study was to evaluate the effects of two different probiotic micro‐organisms on the performance, egg quality and blood parameters of organically reared hens. A total of 900 16‐week‐old Hy‐Line layer hybrids were randomly assigned to three groups of 300 birds each. The control (CTR) group was fed a corn–soya bean cake‐based diet; the L group was fed the same diet supplemented with 0.1% Lactobacillus acidophilus, while the B group was fed the same diet supplemented with 0.05% Bacillus subtilis. Data were recorded at the beginning (weeks 5 and 6: T1) and at the end (weeks 19 and 20: T2) of the experiment, and no differences in hen performance were recorded between dietary groups or sampling times. All of the investigated clinical chemistry parameters, except GGT, were affected by diet (p < 0.05), with the best results recorded for the probiotic‐treated groups. The immune‐response values showed higher blood bactericidal activity in the B and L groups at T2 (p < 0.05) and a lower lysozime concentration in the B group at T1. Higher antibody production against Newcastle disease virus was observed in the L group compared to the CTR (p = 0.013). No differences in oxidative status were recorded, and no effects of diet on egg quality were observed. Among the physical egg characteristics, only the Roche scale colour was affected by diet (p < 0.05): the egg yolk was paler in the L group. The age of the hen was the most relevant factor affecting physical egg characteristics. The chemical parameters of the egg were almost unaffected by supplementation with probiotics except for the lipid content, which decreased with the L diet (p < 0.05). Both probiotic inclusions had beneficial effects on hen metabolism and welfare, and L. acidophilus induced the best immune response.  相似文献   
14.
A study involving 7 white-egg and 3 brown-egg commercial layer strains was conducted at the North Carolina Piedmont Research Station to assess the effects cage population 3-bird vs. 4-bird cages and alternative molt programs on performance through 113 wk of age (791 d). The flock was divided into 3 groups; not molted (NM), maintained in continuous production; molted using feed restriction (FR), an industry-type 14-d feed withdrawal molting program initiated at 463 d of age; and molted using a nonfasted/anorexic program (NF), in which an ad libitum supply of a low protein, low energy molt feed was provided. Productivity, egg size, and egg quality were monitored at 28-d periods throughout the test providing the performance data for the white-egg and brown-egg strains with regard to these management factors. Detailed results by strain are available on the following Web site: http://www.ces.ncsu.edu/depts/poulsci/tech_info.html#layer. The performance for the 3-bird or 4-bird cage groups for either type of layer was similar, except that birds in 4-bird cages had higher feed consumption in the first production phase than did the birds in 3-bird cages. In the same time period the white-egg birds in the 3-bird cages had a greater percentage of cracked eggs and a smaller percentage of Grade A large eggs than those in 4-bird cages. No differences were observed in egg income for the 2 population sizes for either type of layer. However, due to their higher feed consumption, the white egg birds in the 4-bird cages had higher feed cost per hen for the first cycle, which was offset by the egg income component due to their increased production rate. The molted layers outperformed the nonmolted layers for both types of layers in terms of overall income over feed costs. The FR molted hens, under a program that has traditionally been used by commercial producers, outperformed NF-molted hens, indicating that further refinements are needed to make the NF program economically competitive with the FR molting program.  相似文献   
15.
本文调查了蛋鸡养殖场粪便产生量及处理利用现状等基本资料,选点采集养殖场配套龙眼园的土壤样品,通过分析测定有机质、全氮、全磷、铜、锌等指标,探讨了施用蛋鸡粪对龙眼园土壤质量的影响,并对龙眼园土壤环境现状进行评价。结果表明,该养殖场龙眼园土壤粪便当量负荷为19.14t·hm-2,未超过以氮计的土壤粪便当量负荷警戒值。四个季节施用蛋鸡粪的龙眼园土壤中有机质、全氮、全磷、铜、锌等指标均高于未施用蛋鸡粪的橡胶园土壤,但无显著差异;施用过蛋鸡粪的龙眼园土壤有机质、全氮、全磷、铜、锌全年平均含量分别为18.71g·kg-1、0.97g·kg-1、0.79g·kg-1、19.65mg·kg-1和43.05mg·kg-1,均显著高于未施用过蛋鸡粪的橡胶园土壤。四个季节龙眼园土壤和橡胶园土壤铜、锌单项污染指数均小于1,属于安全级别。由于龙眼园施用的蛋鸡粪仅占养殖场蛋鸡粪产生总量的2%,而且采用直接施用鲜鸡粪的方式,因此仍存在环境污染的隐患。本文所得结果可为评估蛋鸡养殖场环境污染风险及与果园结合的蛋鸡养殖模式的合理性提供依据。  相似文献   
16.
为评价高铁高碘日粮对蛋铁碘含量及蛋品质的作用,以含铁25mg ·kg -1 ,碘0 .5m g ·kg - 1 日粮( 对照组) ,铁525m g ·kg -1 ,磺50mg ·kg - 1 日粮( 试验Ⅰ组) ,铁1025m g ·kg - 1 ,碘100mg ·kg -1 日粮( 试验Ⅱ组) 饲喂278 日龄罗曼蛋鸡8 周,观察蛋鸡生产性能、蛋品质、蛋铁碘含量的变化。结果表明,与对照组比较,试验Ⅰ组和Ⅱ组蛋黄铁含量提高了77 % 和124% ,蛋白铁含量提高了6.03 % 和8.59 % ,蛋黄碘含量增加了13.95 倍和17 .62 倍, 蛋白碘含量增加了1.21 倍和1 .87 倍。试验Ⅰ组和试验Ⅱ组血浆铁含量提高了1.15倍和1 .42 倍,血浆碘含量增加了1.53 倍和2 .01 倍。各组间蛋品质无显著差异,但高铁高碘日粮引起蛋鸡生产性能下降。试验结果提示,通过高铁高碘日粮可以大幅度提高蛋中铁碘含量,产蛋母鸡是日粮中铁碘向蛋中转运的良好载体。本试验未发现日粮中高铁高碘之间具有互相协同或互相颉颃作用。  相似文献   
17.
二氢吡啶(Diludin)对产蛋鸡内分泌的影响   总被引:2,自引:0,他引:2  
1 024羽300日龄罗曼蛋鸡随机分4组,分别饲喂二氢吡啶(Diludin)添加量0,100,150,200 mg/kg的4种饲粮,于饲喂后第30日和第80日采血和屠宰,研究其对蛋鸡内分泌功能的影响。结果显 示:Diludin均显著地提高了腺垂体和血清中FSH,LH含量,其中垂体FSH和LH含量随饲喂剂量提高 而增加,血清FSH和LH含量以150 mg/kg组效果最佳;Diludin提高了血清T3含量,T4差异不显著, 30日T3随饲粮中Diludin递增而增加,80日150,200 mg/kg组与对照组差异显著;饲粮中添加Diludin 具有改进血清雌二醇(E2)水平,其中80 日 150,200 mg/kg组与对照组差异显著;150 mg/kg Diludin显 著提高血清中孕酮(P4)含量;饲粮中添Diludin显著提高下丘脑和腺垂体中cAMP含量。  相似文献   
18.
二氢吡啶预防蛋鸡脂肪肝的效果研究   总被引:8,自引:0,他引:8       下载免费PDF全文
选300日龄仙居种肉鸡540羽,随机分成3组(每组设4个重复,每个重复45羽),分别饲喂添加0(对照组)、150和300 mg/kg二氢吡啶的玉米-豆粕型饲粮,以研究二氢吡啶对蛋鸡脂肪肝的影响.结果表明:添加150 mg/kg和300 mg/kg二氢吡啶使蛋鸡平均产蛋率分别提高了9.39%(P<0.01)和12.97%(P<0.01);料蛋比分别降低了9.54%(P<0.05)和7.25%(P<0.05);腹脂率分别下降35.4%(P>0.05)和46.9%(P<0.05);肝脂率分别降低32.4%(P<0.05)和10.5%(P>0.05);腹脂激素敏感脂酶活性升高39.46%(P<0.05)和48.48%(P<0.05); 乳酸脱氢酶活性下降了 32.94% (P<0.01) 和25.16%(P<0.05); 门冬氨酸基转移酶下降了21.78% (P<0.05) 和 7.43%(P>0.05).结果提示:二氢吡啶具有良好的降低肝脂率和提高产蛋率的作用.  相似文献   
19.
为深入了解不同波长光照对母鸡生产性能的影响机理,用c-Fos法探讨了母鸡间脑对不同波长光照的反应,同时检测GnRH免疫反应神经元的动态变化。将150日龄母鸡右眼遮光7 d后接受20 lx的不同波长光照刺激1.5 h,暗适应1.5 h后灌流固定,取脑制作石蜡切片,采用免疫组化方法检测Fos蛋白和GnRH样免疫反应阳性神经元在间脑的分布。结果显示,不同波长光照均影响c-fos基因表达和GnRH的释放,绿光组和蓝光组的表达均高于红光组。  相似文献   
20.
柠檬酸对蛋鸡消化道内容物pH和盲肠菌群的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
选择20周龄宝万斯高兰褐蛋鸡810只,进行6处理3重复单因子试验,分别饲喂添加0(对照组), 0.5,1.5.2.5,3.5和5.5 g/kg柠檬酸(CA)的日粮,于试验第1,2,10和15周周末分别从对照组,0.5.2.5和5.5 g/kg CA添加组每重复选取一只鸡宰杀,测定其消化道内容物pH和盲肠菌群数,研究CA对蛋鸡H粮、消化道pH和盲肠微生物菌群的影响。结果表明,添加0.5~5.5 g/kg CA可显著(P<0.05)或极显著(P<0.01)降低日粮pH;5.5 g/kg CA在添加1周时可显著降低肌胃pH(P<0.05),其余添加组鸡肌胃、小肠、盲肠pH无显著差异(P>0.05);添加2.5,5.5 g/kg CA可有效降低盲肠大肠杆菌数,5.5 g/kg CA在添加1周时可显著提高盲肠乳酸杆菌数(P< 0.05),之后这种作用随添加时间的延长而减小。  相似文献   
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