维生素在种禽孵化和胚胎发育中的重要性

维生素是家禽胚胎正常生长发育所必需的低分子有机化合物。蛋内维生素营养的全价与平衡取决于母禽日粮营养及向蛋内转移的效率。蛋内维生素营养无论是缺乏、过量或不平衡,都会对胚胎发育带来致命的后果。与家畜相比,家禽消化道短、微生物少,大多数维生素在体内不能合     

维生素在种禽孵化和胚胎发育中的作用

维生素是家禽胚胎正常生长发育所必需的低分子有机化合物。蛋内维生素营养的全价与平衡取决于母禽日粮营养及向蛋内转移的效率。蛋内维生素营养无论是缺乏、过量或不平衡都会对胚胎发育带来致命的影响。与家畜相比,家禽的消化道短,微生物少,大多数维生素在体内不能     

维生素在种蛋孵化和胚胎发育中的重要性

维生素是家禽胚胎正常生长发育所必需的低分子有机化合物。蛋内维生素营养的全价与平衡取决于母禽日粮营养及向蛋内转移的效率。蛋内维生素营养无论是缺乏、过量或不平衡都会对胚胎发育带来致命的后果。与家畜相比,家禽消化道短,微生物少,大多数维生素在体内不能合成,少数虽能合成,但不能满足需要,必需依靠从饲料中摄取。当前养禽业采用的各种饲料,除     

维生素对种禽孵化率和胚胎发育的影响

维生素是家禽胚胎正常生长发育所必需的低分子有机化合物。蛋内维生素营养的全价与平衡取决于母禽日粮营养及向蛋内的转移效率。蛋内维生素营养无论是缺乏、过量或不平衡都会对胚胎发育带来致命的后果。与家畜相比,家禽消化道短,微生物少,大多数维生素在体内不能合成,少数虽能合成,但不能满足需要,必需依靠从饲料中摄取。当前养禽业采用的各种饲料,除青绿饲料外,所含维生素的份量多数不能满足家禽需要。必须使用维生素添加剂来补充其不足。目前已知家禽必须从日粮中摄取的微生素有如下几种,按化学结构可以分脂溶性维生素,包括维生…     

自制鸡胚胎发育显示实体模型在孵化工作中的应用

自制鸡胚胎发育显示实体模型在孵化工作中的应用＠王兆山￥山东省滨州农校畜牧组自制鸡胚胎发育显示实体模型在孵化工作中的应用王兆山山东省滨州农校畜牧组︵２５６６２４︶随着养鸡业的高速发展,孵化工作的地位越来越重要,但如何合理控制好孵化的温湿度等使鸡胚正常发育,在...     

维生素缺乏和种蛋管理对种禽孵化率的影响

1维生素对孵化率的影响1.1维生素A种禽维生素A缺乏时,种蛋在孵化后2～3d还未发育成正常的血液循环系统就发生死亡。其后有的胚胎骨骼发育异常,有的无     

硒在种禽营养中的作用

硒是家禽营养中的必需微量元素,对种禽的作用包括改善精液质量、提高孵化率和雏鸡质量等。     

维生素对禽胚胎发育和孵化率的影响

维生素是家禽胚胎正常生长发育所必需的低分于有机化合物。蛋中维生素营养的全价与平衡取决于母禽日粮营养及向蛋中的转移效率。蛋内维生素营养无论是缺乏、过量或不平衡都会对胚胎发育有不良影响。与家畜相比,禽消化道短、肠道微生物少,大多数维生素在体内不能合成,少数虽能合成,但不能满足需要,必须从饲料中摄取。现养禽业使用的饲料,除青绿饲料外,精饲料所含维生素量大多不能满足家禽需要,必须添加维生素补充其不足。目前已知家禽必须从日粮中摄取的维生素,按化学结构可分脂溶性维生素,包括维生素A、D、E、K;水溶性维生素包括硫胺素(VBl)、核黄素(VB2)等。种禽对维生素营养的要求更严格,有时禽群的产蛋量虽没有下降,但种蛋的受精率和孵化率并不高,往往就是由于某些维生素缺乏所致。本文旨在讨论维生素缺乏、过量及各种维生素是否平衡,对孵化率和胚胎发育的影响。     

胚胎发育过程中的水份变化及孵化湿度的地位

众所周知,温度是禽蛋孵化的首要因素,这无论是传统的缸孵、摊孵、平箱孵化还是到现在的孵化器机器孵化,都无可非议,然而孵化过程中的湿度一直存在着异议,总的来说有两种观点,一种观点认为,湿度是孵化过程中不可缺少的必要条件,和温度一样重要,若湿度过低,蛋内水...     

维生素A在家禽营养中的作用

养殖业中饲料大约占养殖业成本的50％—70％。经过20年的飞速发展，养禽业正步入稳产阶段，此阶段家禽企业制胜的关键一方面在于规模化经营(规模效益)和现代管理手段的实施，另一方面则来自于饲料成本的降低。VA自1947年首次人工合成以来，现已成为饲料行业中必不可少的原料，VA的价格高，占维生素成本比重较大，当今饲料和预混料生产厂家都十分注重畜禽日粮中VA的添加，企业找到VA的适宜添加量，既有利于节省成本，又能得到较好的生产效果。本文对VA在家禽营养中的作用进行了全面的论述，希望能引起家禽生产企业对VA使用的注意。     

Influence of egg storage on hatchability, embryonic development and vitamin status in hatching broiler chicks

Storage of eggs for 14 d prior to incubation depressed hatchability by 10%. Most of the increase in embryonic mortality (64%) occurred during the first week of incubation, with a further 30% taking place during the third week. Chicks hatching from stored eggs did not show any increased incidence of physical abnormalities characteristic of vitamin deficiencies. Chicks from stored eggs showed haematological abnormalities characteristic of mild macrocytic anaemia. Such changes can result from deficiencies of folic acid or cobalamin. Biochemical and haematological data did not suggest impairments in the status of the chicks with respect to a range of other vitamins.     

肠道健康对优化家禽生产性能至关重要

肠道健康对生产用动物的生产性能、健康和福利至关重要。除了由常见病原体诱导的肠道疾病之外,消化障碍正逐渐成为另一个日益严重的问题。这些问题的常见特征是发生肠炎和肠道绒毛缩短,它们均会影响动物的生产性能。     

禽蛋质量对孵化率影响的研究进展

种蛋孵化率的高低，主要取决于它的质量、孵化条件及操作技术。种蛋质量的好坏直接影响孵化率和雏禽的品质，因而种蛋质量与养殖业的经济效益和发展密切相关。为此，人们对种蛋质量做了广泛研究。在种蛋内部质量相对稳定的情况下，蛋重、蛋型指数、蛋壳颜色、蛋比重、蛋壳厚度及蛋壳气孔数（通透性）对孵化率的影响尤为重要。本文将对相关的研究作简要综述，可望为选择优质种蛋并提高孵化率提供科学依据。１蛋重对孵化率的影响蛋重是评定家禽产蛋性能和所含营养物质多少的重要指标，种蛋的重量直接影响孵化率的高低及初生雏禽的体重。早在１…     

蚕种催青不同温度对胚子生长发育及实用孵化率的影响

蚕种催青过程中经常碰到胚子发育快慢不同的情况。为了促使各批蚕种发育一致 ,能在预定的发种日期达到预定的发育程度 ,通常采取适当调节催青温度的方法 ,来调节胚子发育速度。调温范围一般以催青标准温度为基础上下浮动 0 .5～ 1℃。但若扩大调温范围 ,对胚子生长发育及实用孵化率会有何影响 ?在生产上是否可采用 ?为此 ,本人在2 0 0 0年及 2 0 0 1年夏期二次试验的基础上 ,于 2 0 0 2年晚秋期再次进行了试验 ,并增加了调查项目。现将试验结果总结如下。1　试验材料和方法1.1　材料 　秋用品种 :薪杭×白云。1.2　方法　Ａ为标准温度催青样…     

Effects of interaction of incubator CO2 levels and mixing hatching eggs of different embryo growth trajectory on embryo physiological and hatching parameters

1. Two experiments were designed to investigate the effects of mixing eggs of different genotype and incubating with different CO₂ concentrations on embryonic parameters. Half of the eggs were incubated in a CO₂ controlled incubator (VCO₂) during the first 10 d of incubation and the other half was incubated at standard incubation ventilation rate (SV).

2. From 10 to 18 d of incubation, thick albumen and embryos were weighed. Blood samples were collected at d 18 of incubation, at internal pipping and at hatch for determination of triiodothyronine (T₃), thyroxine (T₄) and corticosterone concentration. During the last 2 d of incubation, hatching events of individual eggs were monitored every 2 h.

3. From 4 to 5 d of incubation in the SV group of Experiment 1, pH values of Ross strain chickens were lower than those of Isa Brown. From d 12 of incubation onwards, Ross embryos grew faster than those of Isa Brown. At 14 and 16 d of incubation, Ross eggs in the CO₂ controlled incubator had lower albumen weights compared to all other treatments.

4. T₃ concentrations in Ross embryos were higher than those of Isa Brown embryos. Chicken weight at hatch was in the following order: Isa Brown SV < Isa Brown VCO₂ = Ross SV < Ross VCO₂.

5. In Experiment 2, incubation time of VCO₂ eggs until internal pipping, external pipping and hatch was significantly shorter than that of SV eggs.

6. It was concluded that mixing of hatching eggs of differential embryo developmental trajectory affects their hatching process.     

维生素C和维生素E的抗鸡热应激作用

1　热应激对鸡的影响11　热应激　鸡作为恒温动物,仅在严格的环境温度范围内保持体温。10～32℃是鸡维持正常体温的环境温度范围,21～26℃是鸡生存的适宜环境温度,此时鸡用于维持体温所付出的代谢能最少;26～32℃是尚能维持正常体温的温度范围;高于32℃则是鸡生理功能趋于紊乱的温度范围,即出现热应激。12　鸡热应激时的组织、生理、生化及免疫反应121　呼吸频率提高,肺通气量加大,发生热喘息,ＣＯ2排出量增加,致使血液中ＣＯ2分压下降,ｐＨ值升高,严重时出现呼吸性碱中毒。122　心律加快,肝、肾、胃肠道血液流量相对减少,血钙、血钾、血磷…     

Antioxidant systems of the avian embryo: tissue-specific accumulation and distribution of vitamin E in the turkey embryo during development

Tissue-specific accumulation of tocopherols and tocotrienols in turkey tissues during embryonic development and their susceptibility to lipid peroxidation were investigated. Fertile turkey eggs were incubated using standard commercial conditions. Embryonic tissues were collected at 16, 22, 25 d of incubation and from day-old poults (referred to as day 29) and alpha-; beta- + gamma- and delta-tocopherols and respective tocotrienols were analysed by HPLC. A turkey diet provided to the parent hens contained the complete range of tocopherols and tocotrienols. Between days 16 and 22 of embryo development, the alpha-tocopherol concentration in the liver remained constant and then increased significantly (P<0.01) reaching a maximum just after hatching. Similar changes were observed for the other tocopherols and tocotrienols. The accumulation of alpha-tocopherol in the yolk sac membrane (YSM) started after day 20 of development and at hatching the alpha-tocopherol concentration in the YSM was twice that of beta- + gamma-tocopherols and 15 times greater than that of alpha-tocotrienol. In the kidney, heart, lung, muscle and adipose tissues a gradual increase in tocopherol and tocotrienol concentrations took place between days 20 and 25 of development with a sharp increase in particular of alpha-tocopherol between days 25 and 29. There was a discrimination between tocopherols and tocotrienols during their assimilation from the diet by the parent hen and during metabolism by the developing turkey embryo. Tissue-specific features in the susceptibility to lipid peroxidation were found with the brain being the most susceptible to lipid peroxidation at day 25 and in day-old poults.     

Relationship between dietary unsaturation and vitamin E in poultry

Vitamin E requirements are linked to dietary polyunsaturated fatty acids (PUFA) content as a result of the protective effect of vitamin E from lipid peroxidation. On the other hand, it has been suggested that dietary PUFA interfere with vitamin E absorption. A 4 x 4 factorial study was planned to assess the effect of dietary vitamin E inclusion level (0, 100, 200 and 400 mg/kg) and degree of unsaturation (15, 34, 45 and 61 g PUFA/kg) on vitamin E apparent absorption and tissue deposition in poultry. A total of 192 female broiler chickens were used. A digestibility balance was carried out between 19 and 23 days of age to calculate apparent absorption of fat and vitamin E. The livers of 96 animals were obtained at 44 days of age for vitamin E determination. Increasing dietary levels of vitamin E reduced its apparent absorption. The more saturated diet reduced fat and vitamin E apparent absorption while PUFA levels from 34 to 61 g/kg did not modify this parameter but reduced the hepatic vitamin E concentration, suggesting a greater systemic use of this vitamin. These results suggest that PUFA do not limit vitamin E absorption, although they may increase its degradation in the gastrointestinal tract.     

Composition of vitamin supplements in Spanish poultry diets

1. The composition of 106 vitamin supplements used in about 85% of the Spanish poultry production diets were studied. Vitamin supplements were grouped by production classes and, for broilers and pullets, also by feeding periods. 2. Four vitamins (niacin, alpha-tocopherol, pantothenic acid, and riboflavin) comprised over 87% of the vitamin supplements by weight (choline excluded), whereas alpha-tocopherol and retinol represented from 51% to 60% of the total vitamin cost. 3. The highest and lowest vitamin supplementation rates were for broilers in the starter and withdrawal periods (106 and 44 mg/kg, respectively) and the mean values for breeders, pullets and layers were 104, 58, and 48 mg/kg, respectively. 4. Supplements with higher vitamin contents showed less variability in their composition. Retinol, cholecalciferol, riboflavin and pantothenic acid showed the lowest variability within supplements (6% to 36% CV), whereas alpha-tocopherol, menadione, thiamin and biotin showed the highest (40% to 224% CV). 5. Vitamin supplementation rates were compared with requirements, taking into account the dietary contribution. In general, vitamin fortification exceeded the NRC recommendations, using a high safety margin for some vitamins such as vitamin A (from 2.6 to 7.8) and for some poultry classes such as breeders (3.2).