早期营养对雏禽卵黄囊吸收影响的研究进展

卵黄囊是雏禽的一个重要营养来源。雏禽卵黄囊的吸收状况将严重影响其后期的生长发育,而早期饲喂与否、开食料的营养物质含量等因素直接影响到这一吸收过程。为此,文章就卵黄囊的形成及其功能、早期饲喂与禁食及饲料营养含量对卵黄囊吸收的影响等方面的研究进展进行综述。     

肉用仔鹅的饲养技术要点

1 选好雏鹅 雏鹅是指出壳到21日龄的鹅苗。健康的雏鹅重量适中，卵黄吸收好，脐部收缩良好，出壳毛干后能站立，叫声宏亮、活泼，用手握住颈部把它提起时，两腿能迅速收缩，眼明亮有神。在选购时，最好选择本地孵抱房孵出的雏鹅，因在外地引进时容易带入疫病（传染病源），或因长途运输易引起雏鹅不适，影响雏鹅的成活率。其品种选择主要是四川白鹅。2 雏鹅的营养要求及育雏前的准备 四川白鹅早期生长迅速，代谢旺盛，消化力强。在饲养上应充分供给营养，达到快速增长的目的，其饲养标准（参考）0～21日龄雏鹅所需营养标准。每1kg饲料含粗蛋…     

雏鹅的饲养管理与注意事项

雏鹅饲养管理的如何,直接关系到成鹅的生长、发育,及日后的经济效益。雏鹅的饲养管理受多种因素的影响,本文对雏鹅的饲养管理的主要因素及注意事项进行论述。1鹅雏的挑选首先挑选健壮的鹅苗,健康鹅苗的特征是卵黄吸收好,脐部收缩完全,腹部松软,腿部粗壮有力,体重适中,精神活泼,眼睛有神,用力一抓感到其挣扎有力,有弹性。如发现卵黄吸收不完全,可用25W灯泡放     

如何防治雏鹅脐炎

雏鹅脐炎是刚出壳的雏鹅因脐部尚未完全闭合,导致各种细菌进入雏鹅体内发生炎症。一般来说,出壳较晚的弱雏,尤其是卵黄吸收不好的雏鹅在受凉等应激状态下易发生本病。对于本病,应以预防为主。搞好种蛋和孵化器的消毒工作。制定科学、合理的孵化制度,掌握好孵化期间温度、湿度和通风,孵化出优质健雏,尽可能降低弱雏率。在助产时要注意,需待雏鹅的尿囊血管枯萎后方可进行,避免伤着脐部。育雏期间要为雏鹅创造良好的生活条件,前一周尤为重要,要防止受凉,火炕育雏时,炕面温度要适宜,防伤热和着凉,以保证卵黄吸收良好。对卵黄吸收不好的雏鹅用2%…     

雏鹅饲养‘管理的要点

1开水开食 雏鹅出生后,要按照标准程序注射疫苗,避免传染病的发生及流行。第一次饮水称为潮口,潮口后雏鹅即可开食。水分在雏鹅的生长发育过程中很重要,应当引起足够的重视,因为水分是雏鹅最重要的营养,为了防止雏鹅脱水,雏鹅出壳后,应及时补给雏鹅充足清洁的水分。个别养鹅户在开食前给雏鹅饮几滴甘草水或淡绿茶水,可有清理和润滑肠道,起到宽肠、健胃的功效,并能加强腹内剩余卵黄的吸收。     

雏鹅饲养管理应注意的几个方面

1 选优去劣应根据出壳时间和体质强弱做好雏鹅淘汰工作.选留眼大有神、叫声响亮、反应灵敏、毛色光洁、卵黄吸收和脐带收缩良好的雏鹅.对腹大、血脐、大肚脐、跛脚、瞎眼、歪头等弱雏,要做淘汰处理. 2 饮水喂食 出壳15～30小时左右的雏鹅一定要饮水在前,喂食在后.饮水可加少量糖和维生素,有利于清理胃肠、刺激食欲、排出胎粪、吸收营养.喂食时,可用鲜嫩多汁的菜叶切成细丝与半生、半熟的米饭等按2∶1混合,撒在塑料纸上,诱其采食.     

雏鹅的饲养管理六招

1选育壮雏 饲养雏鹅，应选择活泼好动、握之肥壮有力、全身绒毛丰满、卵黄吸收好、脚及脚皮肤丰润有光泽的雏鹅。弱雏一般表现为腹大且硬、腹下无毛、肚脐大、有血迹、站立不稳。对弱雏应淘汰或单独饲养。     

雏鹅饲养管理“六招”

（1）选育壮雏。饲养雏鹅，应选择活泼好动、握之肥壮有力、全身绒毛丰满、卵黄吸收好、脚及皮肤丰润有光泽的雏鹅。弱雏一般表现为腹大且硬、腹下无毛、肚脐大、有血迹、站立不稳。对弱雏应淘汰或单独饲养。     

雏鹅的饲养管理技术浅析

正雏鹅的饲养管理是养鹅生产的一个重要环节,是一项细致的工作,雏鹅的饲养管理直接影响雏鹅的成活率、生长发育和成鹅的产蛋率。若管理不当,就会引起雏鹅发病甚至死亡。所以在雏鹅的饲养管理阶段,应精心饲养。1选择健康正常的雏鹅育雏中,对雏鹅选择非常重要,应选择卵黄吸收好、脐带收缩好、叫声响亮,毛色光亮、眼睛有神的雏鹅来饲养。2雏鹅的饲喂     

冬春季节雏鹅的饲养管理技术

在养鹅生产中 ,育雏是关键 ,冬春季节是养雏鹅的旺季 ,养得好与差 ,直接影响到雏鹅的生长发育和成活率 ,继而影响到育成鹅的生产性能。以下介绍在冬春季节饲养雏鹅的技术要点。１选好雏鹅雏鹅应按出壳的时间和体质强弱严格挑选 ,健壮雏鹅表现为举止活泼、眼大有神、反应灵敏、叫声响亮、挣扎迅速有力、毛色粗长光洁、卵黄吸收和脐带收缩良好 ,将雏鹅仰翻能很快站起。对腹大、血脐、大肚脐、跛脚、瞎眼、歪头等弱雏 ,坚决淘汰。要选留生产性能高的壮年母鹅后代作种用。２分群育雏根据雏鹅大小强弱合理分群 ,达到全群生长均匀、发育整齐的目的…     

幼龄鸡卵黄囊中^3H—VA的吸收代谢及其利用的研究

选用出壳后１２时龄的ＡＡ肉雏１４５只，采用放射性同位素＾Ｈ示踪方法，分别进行了饲养试验，屠补试验和代射试验研究表明，在全价日粮和无ＶＡ纯日粮条件下，雏鸡卵黄囊中的内源性３＾Ｈ－ＶＡ在体内发挥持续时间分别为２１天和１４天。卵黄囊（内源）３＾Ｈ－ＶＡ在鸡肠道中的吸收代谢，与饲料（外源）中营养物质相比，有着独自的特点。卵黄囊中内源３＾Ｈ－ＶＡ在雏鸡肠料中外源ＶＡ之间存在有动态交换关系，内源３＾Ｈ－ＶＡ主     

Dynamics of yolk sac resorption and post-hatching development of the gastrointestinal tract in chickens, ducks and geese

Under similar environmental conditions, 100 male Shaver-Starbro hybrid chickens, 100 male Mulard cross-line ducklings and 100 male Landaise goslings kept in 30 metabolic cages from the first day of life (10 birds of each species separately per cage) were chosen for the study. The animals were fed semi ad libitum diets with crude protein content and energy density similar to that used for poultry species, avoiding feed residues. During the first 21 days of life they received starter diets and from day 22 to 42 grower diets. Maize accounted for 23-40% and barley constituted 10-18%. Wheat accounted for 20.0% in starter diets and 10-18% in grower diets. Resorption of yolk sac residues, performance, development of the intestinal tract in young chickens, ducklings and goslings were assessed. During the first 5 days of life intensive absorption of yolk sac ingredients was observed. On day 7, residues of the yolk sac were found in more than 30% of chickens compared with approximately 10% in geese. In ducklings residues of the yolk sac were not found. On day 16 unabsorbed yolk sacs were found in approximately 10% of chickens. Liver and pancreas weighed the highest in geese and in ducks; in chickens the weight of these organs was significantly lower (p < 0.01). The relative values calculated to 100 g of metabolic body weight show that the average small intestine in chickens was significantly longer (p < 0.01) than in ducks or geese. The intestinal tract developed earlier in the chicken than in the water fowl.     

Effects of breeder hen age and dietary L-carnitine on progeny embryogenesis

1. Ross 308 broiler breeder hens were given diets containing 0 or 25 mg L-carnitine/kg (8 replications per treatment) from 21 weeks of age. 2. Hens were inseminated with semen from Ross broiler breeder males. In a common facility, subsequent progeny hatchability and embryonic mortality at 25, 30, 32, and 38 weeks of breeder age were evaluated. 3. Subsequent egg component weights, incubational egg water loss, progeny embryo growth, and embryo, yolk sac and liver composition through 18 d of incubation at 27, 32, and 38 weeks of breeder age were evaluated. 4. Calculated additions of L-carnitine were in agreement with analysed contents of 3.5 and 31.1 mg free L-carnitine/kg of diet, respectively, and total L-carnitine concentrations increased by 48.6, 21.7, and 10.0% in 0-d yolk, 18-d yolk sac, and 18-d liver samples, respectively, due to the addition of dietary L-carnitine. 5. Supplemental L-carnitine resulted in increased (0.6%) relative 0-d egg yolk weight across weeks 27, 32, and 38, and reduced (0.38%) 18-d yolk sac palmitoleic acid concentration at week 27 without altering embryogenesis. 6. In conclusion, dietary L-carnitine (25 mg/kg of the diet) was deposited in the yolks of broiler breeder hens and was subsequently transferred to the embryonic liver via yolk sac absorption through 18 d of incubation. Furthermore, dietary L-carnitine supplementation increased ovarian follicle yolk deposition in 27-, 32-, and 38-week-old breeder hens, and influenced yolk sac fatty acid beta-oxidation in embryos from 27-week-old breeder hens causing yolk sac palmitoleic acid concentrations to be reduced by 18 d of incubation.     

牛磺酸对肉仔鸡卵黄囊内微量元素转移吸收及生产性能的影响

本试验以Ross父母代肉仔鸡为对象,研究了日粮中添加0.1％牛磺酸对卵黄囊内微量元素转移吸收及生产性能的影响。结果表明:牛磺酸可显著提高肉仔鸡6日龄体重,降低0-45日龄的料重比66％的卵黄囊营养物质吸叫集中在24—72时龄。添加0.1％牛磺酸可使此阶段卵黄囊营养物质消失率提高77.94％,使114时龄卵黄囊营养物质的累积消失率提高16.01％,并显著提高了其中铁、铜、孟、锌、铬的消失率,从而使肝中微量元素铁、铜、锰、锌含量显著升高。     

Influence of Water Provision to Chicks Before Placement and Effects on Performance and Incidence of Unabsorbed Yolk Sacs

A study was conducted to determine the effect of water provision to chicks before placement on performance and the incidence of unabsorbed yolk sacs. To accomplish this, a device was used that was designed to deliver water to chicks in chick baskets during holding at the hatchery and transportation to the growout house. Commercial chicks were obtained from the hatchery and held for either 24 or 48 h with or without access to water before placement. Chicks were then distributed into floor pens with ad libitum access to feed and water. At 6 wk of age, broilers were processed, and intestines were evaluated for presence or absence of an unabsorbed yolk sac and intestinal breaking strength. Body weight at placement was 2 to 6 g greater for chicks given access to water; however, this difference was not observed at any other time during the growout. Water provision during holding had no affect on feed consumption, mortality, or the birds’ ability to completely absorb the yolk sac during the 6 wk growout. Incidence of unabsorbed yolk sacs in 6 wk old birds ranged from 15 to 28%. Moreover, presence or absence of an unabsorbed yolk sac had no effect on intestinal breaking strength. Data from the present study demonstrates that providing chicks with water before placement does not influence performance, intestinal breaking strength, or the incidence of unabsorbed yolk sacs.     

Effect of maternal corticosterone on utilisation of residual yolk sac fatty acids by developing broiler embryo

1. Increased concentrations of maternal corticosterone are deposited into egg yolk under stress conditions. This experiment investigated the effect of maternal corticosterone on yolk and yolk sac fatty acid profiles of eggs and developing broiler embryos. 2. At 42 weeks of age, 200 broiler breeder females were randomly divided into two groups: maternal corticosterone (MC): 2 mg/hen/d of corticosterone dissolved in 1 mL of 99% ethanol and mixed in the individual daily feed for a 14 d period, and control: 1 mL of ethanol added to the individual daily feed. Hens were inseminated, and eggs were collected daily from d 3 of corticosterone feeding to d 14 and incubated. Fatty acid profiles of egg yolk and yolk sac were analysed before incubation and at 12, 14, 18 and 21 d of incubation. 3. Yolk corticosterone concentrations were greater in MC eggs. Before incubation, eggs from MC had lower DHA (22 : 6 n-3) but higher stearic (18 : 0) and dihomo-gamma linolenic (20 : 3 n-6 Cis 8,11,14) acid content compared with the control. 4. Higher concentrations of stearic (18 : 0), elaidic (18 : 1 tr n-9), eicosenoic (20 : 1 n-9), eicosadienoic (20 : 2 n-6), dihomo-gamma linoleic (20 : 3 n-6) and arachidonic (20 : 4 n-6) acids and lower concentrations of myristic (14 : 0), palmitoleic (16 : 1 n-7), linoleic (18 : 2 n-6) and DHA (22 : 6 n-3) were found at different periods of incubation in the residual yolk sac of MC than from controls. 5. The results suggest that the preferentially selective absorption of fatty acids is related to specific tissue requirements.     

Yolk sac, body dimensions and hatchling quality of ducklings, chicks and poults

1. One-day-old chicks of Pekin duck, turkey, layer fowl and broiler fowl were examined for bacteria in the yolk sac and yolk fluid. 2. Whole hatchling, yolk-free hatchling and yolk sac weights were recorded for all species along with crown-rump length and beak-tip to toe-tip length. 3. Bacteriology revealed positive results for the whole yolk sacs of 43 to 64% of the birds in the sample of ducklings, poults and layer chicks. Broiler chicks had a 6.6% incidence of bacteria isolated from the whole yolk sac. By contrast, there were very few positive results from swabs of yolk fluid for any of the bird types. 4. The presence of bacteria in the yolk sac of hatchlings suggests that there is colonisation, rather than infection, of the yolk sac membrane during the hatching period or the first few hours post-hatching. Isolation of bacteria from the yolk sacs of young chicks might no longer be considered as solely indicative of yolk sac infection but further research is required to confirm this result. 5. Contrary to what is being suggested in commercial practice relationships between linear dimensions and hatchling weight suggest that measurement of chick length is at best a very crude measure of chick quality.     

Natural Occurrence of Campylobacter Species,Salmonella Serovars,and Other Bacteria in Unabsorbed Yolks of Market-Age Commercial Broilers

In the developing avian embryo, the main energy source is the yolk. Toward the end of the incubation period, the remaining yolk sac is internalized into the abdominal cavity. At hatch, the remaining yolk comprises 20% of the chick's BW and provides the nutrients needed for maintenance. Posthatch, chicks rapidly initiate the transition from yolk dependence to the utilization of exogenous feed. However, at present, it is not known what types of bacteria are found to be associated with unabsorbed yolk sacs from market-age broilers. For Experiment 1, one hundred 6-wk-old defeathered broiler carcasses were obtained from a commercial processing facility during each of 3 visits. In the second experiment, one hundred 8-wk-old defeathered broiler carcasses were obtained from a different commercial processing plant on 4 separate occasions. For both experiments, each carcass was aseptically opened and inspected for the presence of an unabsorbed yolk sac. Three to 5 carcasses containing a free-floating yolk sac (within the abdominal cavity) and the yolk stalk (without a yolk sac) and 3 to 5 carcasses containing an attached yolk and yolk stalk from each repetition were randomly selected and analyzed for levels and types of total aerobic bacteria (APC), Enterobacteriaceae (ENT), and for the presence of Campylobacter spp. and Salmonella serovars. The APC ranged from log 3.3 to >log 6.0, and the ENT ranged from log 2.8 to >log 6.0. Staphylococcus spp. and Streptococcus spp. were the predominant organisms in APC, whereas Escherichia coli and Hafnia alvei were found to comprise the ENT. Campylobacter spp. was found in 29% of the yolk stalks, 32% of the attached yolk sacs, and 13% of the free-floating yolk sacs. All Campylobacter isolates were determined to be Campylobacter jejuni, except for 1 attached yolk and yolk stalk, which was Campylobacter coli. Salmonella serovars were found in 26% of the yolk stalks, 48% of the attached yolk sacs, and 23% of the free-floating yolk sacs, and the majority of Salmonella isolates were Salmonella Typhimurium. The significance of these bacterial reservoirs and carcass contamination during processing is yet to be determined.     

Die ontogenetische Entwicklung des Dottersackstiels der Hausvögel und seine Rolle bei der Absorption des Dotters

The ontogenetic development of the stalk of the yolk sac in domestic birds, and its role in the absorption of the yolk Development and structural changes of the stalk of the yolk sac were studied experimentally using light and electronmicroscopy. The development begins on day 5 of incubation and ends on day 7–8. The muscular layer of the stalk is translucent in two or three places. The intestinal end of the stalk in the chicken and turkey forms a papilla which is provided with a sphincter and projects into the lumen of the intestine. Goose and duck have neither papilla nor sphincter. The diverticulum ductus vitellini is characteristically invaded by lymphocytes and in the goose and duck this lymphoid tissue reaches the organisation of fossulae. The stalk remains patent until postnatal day 3–7. Beginning on day 5 of incubation some yolk flows through the stalk into the intestine; from day 15 of incubation onward a little more, and during the closure of the umbilious on day 17, a large amount of yolk flows into the intestine, but this flow is reduced after hatching. The yolk is regurgitated into the glandular stomach and absorbed on its way there. Experimental evidence indicates that, from the day 11 of incubation onward, swallowed egg white reaches the yolk sac through the stalk.     

Histochemical observations on the enzymes of chicken yolk sac membrane

In the endodermal cells of the yolk sac membrane of chicken embryos incubated for 12 to 18 d, the activity of glucose‐6‐phosphatase (G‐6‐Pase) was high, the activity of acid phosphatase (Acid Pase) was moderate, the activities of lactate dehydrogenase (LDH) and of glyceraldehyde‐3‐phosphate dehydrogenase (G‐3‐PDH) were low, and succinate dehydrogenase (SDH) and alkaline phosphatase (Alk Pase) activities were not detected. On the day before hatching, however, SDH became evident with low activity, and the activities of Acid Pase, LDH and G‐3‐PDH increased and remained higher until the day after. Five days after hatching, there were marked decreases in the activities of all the enzymes except SDH. Alk Pase was not detected at any time. The function of the yolk sac endo‐derm in the absorption of yolk is discussed in the light of these observations.