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1.
Production of eggs or normal chicks was depressed when practical diets containing 168 g or 137 g of crude protein (CP)/kg were not supplemented with synthetic biotin. Overall egg production and hatchability of fertile eggs was significantly (P less than 0.05) higher with the diets containing 137 g CP/kg. Biotin requirement was higher with the diet containing 168 g CP/kg and was estimated to be about 100 micrograms of available biotin/kg, equivalent to a daily intake of 16 micrograms for food-restricted hens. Biotin concentrations in egg yolk and chick plasma were related to maternal intake and increased with maternal age. The minimum yolk biotin concentration indicative of adequate maternal status was about 550 micrograms/g. Chicks from young hens fed insufficient biotin had the poorest biotin status at hatching and their growth potential and viability were reduced. 相似文献
2.
[目的] 研究相同饲养条件下海兰褐蛋鸡苗和京粉2号蛋鸡苗的生长发育规律,评价其初产蛋品质。[方法] 选取1日龄海兰褐蛋鸡苗和京粉2号蛋鸡苗各500只,在相同条件下饲养,每周随机挑选60只个体测量体重,直到13周龄试验结束。采用Logistic、Gompertz 和Von Bertalanffy 3种曲线模型对2种鸡苗的生长发育情况进行拟合。上笼后约30 d,观察和收集2个品种蛋鸡的初产蛋（第一枚蛋）,测定并比较其蛋品质指标。[结果] 2个品种的鸡苗在4~5周龄的生长速率最快。2种鸡苗的日绝对平均增重和相对生长率不同。Logistic、Gompertz 和Von Bertalanffy 3种曲线模型对2种鸡苗的生长发育拟合效果均较为理想,但Gompertz模型的拟合度更高、适合性更强,为最佳生长模型。在初产蛋品质比较中,除蛋宽和蛋形指数外,其余指标均表现为海兰褐蛋鸡的鸡蛋显著（P<0.05）大于京粉2号蛋鸡。[结论] 研究结果可为海兰褐蛋鸡和京粉2号蛋鸡的开发利用及品种改良提供参考。 相似文献
3.
Pregnenolone, progesterone, deoxycorticosterone and corticosterone were injected into hens between 16.30 and 17.00 h on the day of oviposition of the last egg of a sequence. 2. Pregnenolone did not affect ovulation, but all of the other steroids induced ovulation prematurely. 3. To induce premature ovulation in 50% of the hens, 82-31 mug+/-0-06 mug, 23-86 mug+/-0-07 mug and 659-26 mug+/-0-05 mug of progesterone, deoxycorticosterone and corticosterone, respectively were required for injection. 4. Differences were observed in the times of oviposition of eggs which ovulated in response to injections of either progesterone or a corticosteroid and it was suggested that the mechanism of action of progesterone and corticosteroids operates through different endocrine pathways. 相似文献
4.
Relationship between the weight of hatching eggs and subsequent early performance of broiler chicks 总被引：3，自引：0，他引：3
Y Pinchasov 《British poultry science》1991,32(1):109-115
1. The effect of egg weight on the subsequent performance of individual growing chicks was studied. Eggs from commercial broiler breeder hens were collected at 52, 55 and 57 weeks of age and incubated. The chicks were reared for 18 d. 2. Egg weight and hatched chick weight were not affected by the age of the hens during the 52 to 57-week period, but there was a close correlation between egg weight and hatching weight, irrespective of the age of the hens (r = 0.89). Chick:egg weight ratio at hatching was about 0.71 and independent of hen age. One d after hatching, chick weights had decreased by about 1.5 g. 3. The initial high correlation between egg weight and chick weight decreased markedly during post-hatching growth, becoming insignificant 5 d after hatching. At 18 d of age, however, chicks from eggs of older hens tended to be heavier than those from younger birds. The greater 18-d weights appeared to be associated more with higher food intake during that period, than with greater egg weight. 4. It was concluded that, in individual broiler chicks, the advantage of the initially higher weight attributable to a larger egg diminishes rapidly after hatching, and the main factor affecting final body weight is food intake. 相似文献
5.
During the first 4 weeks of egg production, there were no differences in the plasma concentrations of prolactin and corticosterone, egg production, body weight and the consumption of food and water between turkey hens which were maintained in cages or in floor pens. The plasma concentration of prolactin increased to the same extent in both environments during the period of peak egg production. A further rise in concentration of prolactin occurred in association with the termination of oviposition in 15 of the 19 hens which stopped laying eggs. Prolactin appeared to be progonadal and then antigonadal, once a threshold concentration was exceeded. This threshold value was higher in caged turkey hens. After laying ended, high concentrations of prolactin in hens maintained in cages were not maintained in the absence of a stimulus or stimuli associated with the nests. 相似文献
6.
1. A 6-week trial was conducted to evaluate the effects of pearl millet (PM) as a replacement for maize, in combination with flaxseed (FS), on productivity, egg trait parameters and egg n-3 fatty acid (FA) content in White Leghorn hens. 2. Six diet treatments were used: a control (CTL, maize-soybean meal based) diet, and diets containing 0, 2, 4, 8 or 12% FS, in which all maize was replaced by PM (PM-0, PM-2, PM-4, PM-8 and PM-12, respectively). All diets were isocaloric and isonitrogenous and met NRC (1994) requirements. Eight cage replicates per treatment were used (three hens per cage). At the end of each week, three eggs were randomly collected from each cage to measure egg trait parameters and yolks were separated, pooled and lyophilised for FA determination. Body weights and feed consumption were recorded weekly. Egg production (number of eggs and egg mass produced) was recorded daily. At the end of the experiment, all hens were killed to determine liver haemorrhage score. 3. Egg traits and flock performance parameters were not different among treatments except at week 4, when birds on the PM-12 diet produced smaller eggs than hens on the PM-0 and PM-2 diets. Yolk pigmentation scores were lower for the PM-0 and PM-2 diets (1.60 +/- 0.24 and 1.80 +/- 0.20, respectively), increased with higher inclusions of FS (2.75 +/- 0.47 for PM-12 diet) but did not reach control levels (6.00 +/- 0.01). Liver haemorrhage scores were not affected by dietary treatment. Hens given the PM-8 and PM-12 diets produced eggs with n-3 FA content higher than required to be considered as n-3 FA enriched eggs, and had a lower n-6/n-3 FA acid ratio than eggs of hens consuming CTL or the PM based diets with lower FS supplementation. 4. These results suggest that PM can be used to substitute for maize in the diets of layers and may reduce the amount of FS needed to obtain n-3 FA enriched eggs. 相似文献
7.
Exposing a pregnant mammal to stressors causes behavioral and physiological alterations in her offspring ("prenatal stress"); however, elucidation of the underlying mechanism is hindered by an inability to control maternal compounds that may affect the fetus. We designed this experiment to determine if the autonomously developing chicken embryo could be developed as a model for prenatal stress. On d 16 of incubation, eggs were treated with: 1) 60 ng corticosterone (CORT), 2) elevated incubation temperature (40.6 degrees C) for 24 h (HEAT), or 3) no treatment (Control). Chicks from all three treatments hatched at similar weights; however, HEAT chicks weighed less by 100 d of age and remained lighter until the end of the study (P < 0.05). At 8 d post-beak trimming, adrenal gland weight was not different (P > 0.20) among treatments, basal plasma corticosterone concentrations tended (P < 0.06) to be greater for CORT chicks than either the Control or HEAT chicks, and CORT chicks were heavier than HEAT chicks (P < 0.005) but not Control chicks (P > 0.20). At 11-wk, HEAT birds had heavier adrenal glands than did Control birds (P < 0.01). At 16 wk of age, Control cocks performed more (P < 0.01) pecking aggression than either HEAT or CORT cocks, whereas CORT cocks were chased more often and chased another cock less often than either HEAT or Control cocks (P < 0.01). Treatments did not alter the behavior of the hens (P > 0.10). Administration of corticosterone during incubation replicated some, but not all, of the effects seen in prenatal stress in mammals. 相似文献
8.
Lack of effect of oviposition time and parental age on chick weight when egg weight remains constant
A L Yannakopoulos 《British poultry science》1988,29(2):431-434
1. An experiment was conducted utilising 480 eggs from broiler breeder hens to determine the effect of oviposition and parental age on 1-d-old chick weight when egg weight remained constant. 2. Neither the age of the breeder flock nor the time of oviposition had a significant effect on egg weight loss during the 18 d of incubation. Nor was there any effect on chick weight: egg weight ratio and 1-d-old chick weight when chicks were removed and weighed at the same time. 3. Hatching time was significantly affected by time of oviposition and age of parents. Afternoon eggs or eggs from older hens tended to hatch earlier than morning eggs or eggs from younger ones. 相似文献
9.
The effect of free-range versus cage management system on corticosterone transfer into the eggs was studied in laying hens. Hungarian Yellow laying hens (age: 21 weeks, body weight: 2.0 +/- 0.5 kg) were divided into two groups in the spring: Group I, free-range keeping (n=15 layers, density: > 0.5 bird/m2) in outdoor runs, with continuous access to a commercial layer feed; Group II, hens kept in battery cages (n=17 layers, density: 2 birds/m2, natural light, continuous access to feed and water). Eggs were collected after a one-week adaptation period on days 2, 7 and 16. Corticosterone (CST) was extracted from homogenised egg samples using an ASE-200 Accelerated Solvent Extractor and then assayed by liquid chromatography linked with tandem mass spectrometry (LC-MS/MS) [Thermo Quest Surveyor high-performance liquid chromatography (HPLC) interfaced via Atmospheric Pressure Chemical Ionisation (APCI) ion source to Finnigan/Thermo Quest LCQ Deca MS/MS] using dexamethasone as internal standard with positive APCI ionisation. CST concentrations of whole eggs laid by free-range hens on days 2, 7 and 16 were 0.370 +/- 0.218, 0.259 +/- 0.066 and 0.915 +/- 0.745 ng x g(-1), respectively, while those of eggs laid by caged hens were 0.206 +/- 0.157, 0.223 +/- 0.165 and 0.184 +/- 0.110 ng x g(-1) at the above sampling times. It is concluded that in free-range laying hens the sharp changes of environmental weather conditions significantly increased the corticosterone content of eggs, while the environmentally controlled and closed battery cage management technology resulted in relatively uniform corticosterone concentrations in the whole eggs. 相似文献
10.
1. The presence of histamine in egg yolk, its losses during storage, incubation and heating, and its relationship to cage density stress and the egg production status of hens are described. 2. A significant (P less than 0.05) reduction in the histamine concentration of egg yolk was noted after incubating or heating egg yolks or on storage eggs. 3. Histamine concentration was greater in the yolks of high egg producing hens. 4. The concentrations of histamine in egg yolks did not change significantly (P less than 0.05) on keeping the hens individually in a cage, pairing them in the same size cage or after separating them again to individual cages. 相似文献
11.
Effect of a single injection of adrenaline on shell ultrastructure in a series of eggs from domestic hens 总被引：1，自引：0，他引：1
1. Adrenaline (1 mg in 1 ml water) was administered subcutaneously to three hens to determine whether any changes in the shell ultrastructure of subsequent eggs would occur. 2. The egg shells were examined in a scanning electron microscope after plasma etching. 3. The first three eggs laid by each bird after adrenaline injection were compared with previously-collected normal eggs from the same birds and also with control eggs collected over the same period from three hens which had received no adrenaline. 4. The first egg laid following adrenaline treatment was essentially normal but both the second and third eggs showed severe structural disorganisation at all levels, from the mamillary caps up to the cuticular layer. 5. Eggs laid 20 d or more after adrenaline treatment had reverted to normal. 6. The findings suggest that the abnormal eggs laid after hens have been exposed to disturbance or stress are likely to be affected in not only their external appearance but also to be of poor structural quality. 相似文献
12.
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. 相似文献
13.
14.
《The Journal of Applied Poultry Research》2008,17(3):323-330
A 4 × 2 × 2 factorial experiment with 4 dietary energy levels (2,776, 2,820, 2,864, and 2,908 kcal/kg) and 2 strains (Bovans White and Dekalb White) with and without Tylosin was conducted to determine the influence of dietary energy and antibiotic on performance, egg solids, and egg quality. The experiment lasted 10 wk. Bovans White hens (n = 768) and Dekalb White hens (n = 768) at 55 wk of age were randomly divided into 16 treatments (8 replicates of 12 birds per treatment). Bovans hens had significantly greater egg production and significantly lower egg weight, egg-specific gravity, and shell weight than Dekalb hens. Increasing dietary energy by the addition of poultry oil had no significant effect on performance, egg solids, or eggshell quality. An ideal dietary energy level for optimal performance could not be determined. There can be no fixed ideal dietary energy level for optimal profits, due to varying feed ingredient and egg price. Although Tylosin supplementation had no effect on performance or egg solids, Tylosin significantly reduced dirty eggs, resulting in a positive effect on egg quality. 相似文献
15.
H. NIELSEN 《British poultry science》1998,39(1):53-56
1. Total lipid, total cholesterol, and phospholipid contents per gram of egg yolk were found to be the same for eggs from 21 and 57 week-old hens. 2. In contrast, fatty acid composition of total egg yolk lipid was different for the 2 groups of hens. The contents of long-chain (20 C and 22 C) polyunsaturated fatty acids of n-6 and n-3 series were 20% to 25% higher in egg yolks from the younger hens. 3. This finding is discussed with respect to the nutritional value of eggs from hens of different ages regarding the use of egg yolk lipid in the production of infant formulae. 相似文献
16.
17.
Livestock production in central Mali: Reproduction,growth and mortality of domestic fowl under traditional management 总被引：1，自引：1，他引：0
R. T. Wilson A. Traore H. G. Kuit M. Slingerland 《Tropical animal health and production》1987,19(4):229-236
In an 18-month study the domestic fowl in 42 households in three traditional management systems were recorded to determine reproduction, growth and mortality parameters. There were significant differences for all systems combined in the number of clutches started per month with the lowest number being laid in the cool dry season of January and February. Mean number of eggs per clutch was 8.8; the number of eggs increased significantly throughout the career of the hen but there were no significant systems differences. Egg weight was 34.4g there being no significant differences due to age of hen or system. Intervals between clutches were 92 days, annual egg output was 35 per hen (assuming that birds were present in the flock for a year) equivalent to about 118% of mean adult hen body weight: hens actually in the flocks during the study had produced 2.1 clutches on average. Hatchability of eggs was 69.1% there being significant seasonal and systems differences in this parameter, lowest hatchability being in the hot dry season (March to June) and in the rainfed millet system. Mortality rates to eight weeks were 56% of chicks hatched. Growth to 10 weeks averaged 4g/d. Mature cocks weighted 1.60 kg and mature hens 1.02 kg: hen weights were significantly affected by reproductive state, laying hens being heavier than both incubating hens and those rearing chicks, while those rearing chicks were heavier than those incubating. Suggestions for improving productivity are made. 相似文献
18.
The breeding performance of captive willow ptarmigan on different diets has been studied. The nutritional factors tested were protein concentration, natural feed supplement and grass meal and flavonoid admixture, and effects on egg numbers, fertility, hatchability, chick weights at hatching and 0–14 days mortality have been recorded.The breeding performance of ptarmigan hen in captivity showed great individual variations. Egg numbers were not statistically different in groups fed the different diets. Hens fed a 15 % crude protein died tended to produce smaller chicks with significantly lower viability than chicks from hens fed a 20 % crude protein diet. Supplement of natural feed tended to increase the number of chicks hatched through a combination of tendency to higher egg numbers and improved fertility. These tendencies were, however, statistically nonsignificant. Inclusion of 34 % grass meal to the diet also tended (non-significantly) to improve fertility and hatchability, while inclusion of flavonoids had no positive effect on reproduction.Eggs from captive hens showed significantly lower fertility, and a tendency to lower hatchability than eggs from wild hens. The former difference was probably caused by the close cage confinements for the captive ptarmigan, while the latter condition probably was due to different start of incubation, most of the eggs from wild hens being started naturally. 相似文献
19.
Sang-Geon Yeo Eva Nagy Peter J Krell 《Journal of veterinary diagnostic investigation》2003,15(2):184-187
Attempts were made to establish methods for indirect prediction of hemagglutination inhibition (HI) antibody titers to Newcastle disease virus (NDV) in sera of laying hens and day-old chicks by determining if these are correlated to HI titers in egg yolks. For this purpose, geometric means of HI antibody titers in sera from 60 hens, yolks from 60 matched eggs, and sera from 180 day-old chicks of an identical vaccination program were measured and plotted. There was a significant correlation between HI antibody titers in yolks (X) and hens (Y), with a linear regression of Y = 23.24 + 0.47X and a correlation coefficient of r = 0.65. The linear regression between HI antibody titers in yolks (X) and chicks (Y) was Y = 6.33 + 0.36X (r = 0.58). Immunity to NDV in hens and their offspring can be maintained effectively, and the proper time for the vaccination or booster can be determined by reference to HI titers predicted from the linear regression in the present study. The approach of testing egg yolk for HI titers provides a feasible alternative to determining HI titers from blood samples and eliminates stress in birds during blood sampling. 相似文献
20.
Effect of selenium and vitamin E content of the maternal diet on the antioxidant system of the yolk and the developing chick 总被引：11，自引：0，他引：11
Surai PF 《British poultry science》2000,41(2):235-243
1. The effects of selenium and vitamin E supplementation of the maternal diet on their transfer to the egg yolk and tissues of the newly hatched chick and on the development of the antioxidant system in the chick liver in early postnatal life were investigated. 2. One hundred Cobb broiler breeder hens were divided into 10 equal groups and housed in pens at 25 weeks of age. Each hen received 1 of the treatment diets which included 0.2 or 0.4 mg/kg selenium, 40, 100, 200 mg/kg vitamin E or their combination. After 6 weeks, the hens were artificially inseminated once per week. From week 8, eggs were collected and placed in an incubator. After hatching, chicks from each group were reared (under standard commercial conditions) to 10 d of age. The chicks were fed on a standard starter commercial broiler diet. At the time of hatching, and at 5 and 10 days old, 4 chicks from each group were sacrificed and blood, liver and brain were collected for the subsequent biochemical analyses. 3. The inclusion of organic selenium or vitamin E in the commercial diet significantly increased their concentration in the egg and in the liver of 1-d-old chicks obtained from the eggs enriched with these substances. A positive effect of such dietary supplementation was seen at d 5 and d 10 of postnatal development. 4. There was a positive effect of selenium supplementation of the maternal diet on glutathione concentration in the liver of 1-d-old and 5-d-old chicks. A combination of a dietary selenium supplementation with high vitamin E doses further increased glutathione concentration in the liver. Dietary selenium supplementation significantly increased selenium-dependent glutathione peroxidase (Se-GSH-Px) activity in the liver of the 1-d-old and 5-d-old chicks and decreased liver susceptibility to peroxidation. 6. It is concluded that the nutritional status of the laying hen determines the efficiency of the antioxidant system throughout embryonic and early postnatal development of the offspring. 相似文献