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1.
This study set out to investigate if access to an enriched environment during the rearing phase influences subsequent production and eggshell quality in broiler breeders. Broiler breeder pullets were reared under standard rearing conditions (control treatment) or under standard conditions with an environmental enrichment of bales of plastic-wrapped wood shavings (enriched treatment). At 19 weeks of age both groups were transported to a laying facility and housed in standard pens according to treatment type. Egg weight, shape, shell thickness, non-destructive deformation, breaking strength, stiffness and ultrastructural quality were compared at beginning of lay (25 weeks old), peak production (31 weeks old), mid-lay (45 weeks old) and end of lay (57 weeks old). Production and hatchery data were also collected throughout lay. Significant treatment-age interactions were detected for non-destructive deformation, breaking strength and stiffness, such that birds which had received prior enrichment went on to maintain a better shell quality with age. The measurements of total shell thickness, mammillary thickness and effective shell thickness all showed a trend for a treatment-age interaction. Significant age effects were found for weight, shape index, shell thickness, breaking strength and stiffness. All production and hatchery data also demonstrated significant changes with age. It is concluded that early enrichment with bales of wood shavings may provide a novel approach to the maintenance of eggshell quality at a time when calcium metabolism begins to reduce in efficiency. 相似文献
2.
1. This experiment was carried out to determine the effects of dietary iodine supplementation on the performance and egg traits of laying hens. A total of 600 SHSY type brown layers aged 21 weeks of age were chosen at random from a large flock. They were randomly distributed into 30 pens at 20 hens per pen. Each treatment comprised 6 replicates of 20 layers in groups of 5 birds. The diets were supplemented with 0, 3, 6, 12 and 24 mg/kg iodine as calcium iodate. The experimental period lasted 30 weeks. 2. There were no significant differences among the groups in body weight, food consumption, egg production, food consumption per kg eggs, eggshell index, eggshell breaking strength, shell thickness or egg yolk index. 3. Supplementation of the diet with 12 mg/kg iodine increased food consumption per dozen eggs compared to the groups fed on diets supplemented with 0 and 6 mg/kg iodine. 4. Egg weight was less in groups fed on diets supplemented with 12 and 24 mg/kg iodine than in the group receiving no iodine supplementation. 5. Iodine supplementation to provide 12 and 24 mg/kg reduced egg albumen index and egg Haugh units. 6. There were no significant differences among the groups in egg cholesterol and egg yolk cholesterol contents. 7. The iodine concentrations in egg yolk, egg albumen and whole egg increased with increased iodine supplementation. 8. As a result, the 3 and 6 mg/kg iodine supplementation of diet could be used to enrich the eggs with iodine without any adverse effect on performance and egg traits. 相似文献
3.
不同周龄母鸡鸡蛋及不同蛋壳质地鸡蛋的蛋品质比较 总被引：1，自引：0，他引：1
本文比较了同一品种不同周龄(26、40周龄和64周龄)母鸡所产蛋的蛋壳品质和蛋品质,包括蛋重、蛋壳相对重、蛋形指数、蛋壳强度、蛋壳厚度、蛋黄颜色、蛋黄指数、蛋黄比率、哈氏单位、蛋清pH值。之后,还比较了该鸡种不同蛋壳质地鸡蛋(正常蛋和砂壳蛋)之间上述指标的差异。结果表明:在不同周龄母鸡所产蛋之间,蛋重、蛋黄指数、蛋黄比率、哈氏单位等均存在显著差异(p<0.05),而蛋壳厚度之间差异不显著(p>0.05)。此外,蛋重、蛋形指数、蛋黄颜色、蛋黄比率随着母鸡周龄的增加呈上升趋势,而蛋壳强度、蛋壳相对重、哈氏单位、蛋黄指数、蛋清pH值呈下降趋势。最后,蛋壳质地不同的鸡蛋(正常蛋与砂壳蛋)之间,蛋重、蛋壳相对重、蛋壳强度、蛋清pH值之间存在极显著差异(p<0.01),而其他参数之间差异不显著(p>0.05)。 相似文献
4.
本文旨在研究蛋壳表型性状与蛋壳强度之间的相关与通径分析。试验选用40~43周龄的新鲜珍珠鸡蛋100枚,测定了其蛋重、蛋形指数、蛋壳厚度、蛋壳重、蛋壳比例、单位面积蛋壳重、蛋壳强度6个指标,计算其性状间的相关系数;采用通径分析方法计算以表型性状为自变量对蛋壳强度作因变量的通径系数、决定系数对各性状的影响大小进行分析。从通径分析结果看出,直接影响最大的是蛋壳厚度（P=0.657）,间接影响最大的是蛋壳比例（0.746）,并以蛋壳厚度指标建立回归方程为y=44.145x-9.229。在生产实践中,为获得好的蛋壳质量应着重注意蛋壳厚度和蛋壳比例,同时要协调蛋形指数、蛋重、蛋壳比例、单位面积蛋壳重与蛋壳强度之间的关系。 相似文献
5.
1. ISA Brown and Shaver 238 pullets were changed from 8 h to 8, 10, 13 or 16 h photoperiods at 42, 63, 84, 105, 126 or 142 d of age.
2. Age at first egg (AFE) was curvilinearly affected by the size and timing of the change in photoperiod. AFE was advanced most by a photoperiod change from 8 to 13 h made at 63 or 84 d. ISA birds were generally more responsive than Shaver to the photoperiod changes.
3. Longer photoperiods significandy increased survivors' egg production, but decreased liveability to 504 d, so that eggs per hen housed were unaffected. Retarding AFE by 10 d reduced survivors' egg numbers by 7.0, but increased mean egg weight by 1.26 g. Egg output by Shaver birds was unaffected by AFE, but that of ISA was curvilinearly affected, with an apogee at an AFE of 135 d. In both breeds, egg weight and egg output were greater following an early or late, rather than a mid‐term photostimulation.
4. Photoperiod significandy increased mean daily food intake during lay by 1.26 g/h. A 10 d retardation in AFE resulted in a reduction in food intake of 1 g/d. Efficiency of food conversion deteriorated according to the square of the photoperiod, and changed curvilinearly according to age at photostimulation. Food conversion efficiency improved by 0.05 g/g for each 10 d delay in AFE.
5. Shell quality was unaffected by AFE, but deteriorated with increasing photoperiod and was curvilinearly affected by age at photostimulation with the smallest shell weights associated with photostimulation at 63 d. The incidence of double‐yolked (DY) egg production increased with photoperiod and decreased with delayed photostimulation. There was an exponential regression of DY eggs on AFE.
6. Body weight at first egg increased by 75 g/d delay in AFE, but body weight at 504 d of age was unaffected by AFE, photoperiod or age at photostimulation. Body weight gain during lay increased by 15 g/h increase in photoperiod, decreased by 6 g per 10 d delay in photostimulation and by 40 g per 10 d delay in AFE. Fat content at 504 d increased by about 10 g/kg and by 23 g/bird for each 10 d delay in AFE.
7. Mortality in lay increased by 0.8%/h increase in photoperiod, but was unaffected by either age at photostimulation or AFE. 相似文献
6.
1. Egg‐shell colour, egg specific gravity, shell thickness and egg weight were determined for 2080 eggs from three varieties of the Vasca, a Spanish brown‐egg‐laying hen. 2. Intermediate, positive and significant (P < 0·01) correlation coefficients were found between egg‐shell colour and specific gravity (0·25), or shell thickness (0·21). There was a very high (0·84), significant (P < 0·01) correlation between the measures of shell strength. 3. Shell thickness was accurately predicted with both specific gravity and egg weight as independent variables (determination coefficient 0·74); eggshell colour did not explain any further variation. 4. All traits showed considerable departure from normality in the form of negative kurtosis (shell colour and specific gravity), positive kurtosis (shell thickness and egg weight), negative skewness (shell thickness) or positive skewness (egg weight). 5. Egg‐shell colour, specific gravity and shell thickness were less in July, in old birds and in eggs laid in the morning. Differences in egg quality traits between the three varieties were not significant. 相似文献
7.
Forty-five-week-old commercial leghorns negative for antibodies to Mycoplasma gallisepticum (MG) and M. synoviae were vaccinated with high-passage F strain MG (FMG). Hens were confined in modified Horsfall-Bauer isolation units through 60 weeks of age. Egg production (% hen day) and parameters of egg and eggshell quality were monitored, including egg weight, eggshell strength, Haugh unit score, pimpling, and blood/meat spot incidence. Egg production was significantly lower (P less than 0.05) for FMG vaccinates than controls (down 5.76% and 5.80% in Trials 1 and 2, respectively). However, vaccinates and controls did not differ significantly in eggshell strength, shell thickness, pimpling, or blood/meat spot incidence. Haugh unit scores were significantly (P less than 0.05) greater for FMG vaccinates. At necropsy, all reproductive tracts appeared grossly normal. These studies suggest that high-passage FMG vaccination of post-production-peak hens does not adversely affect oviduct function. 相似文献
8.
New approach of testing the effect of heat stress on eggshell quality: mechanical and material properties of eggshell and membrane 总被引：1，自引：0，他引：1
Lin H Mertens K Kemps B Govaerts T De Ketelaere B De Baerdemaeker J Decuypere E Buyse J 《British poultry science》2004,45(4):476-482
1. The effect of high temperature on eggshell quality was investigated by measuring the mechanical and material properties of shell and membranes. 2. Heat exposure resulted in a decrease in zootechnical performance and eggshell thickness, increase in egg breakage, and unchanged egg shape index. 3. The static stiffness (Kstat), dynamic stiffness (Kdyn) and modulus of elasticity of the eggshell were not significantly affected by high temperature. Membrane prolongation increased significantly while membrane attachment strength and breakage strength tended to decrease and increase, respectively. The relationships between these variables were changed by high temperature. 4. Neither Kstat nor Kdyn could give a reasonable explanation for the changed eggshell quality induced by heat stress. The decreased eggshell thickness and changed properties of shell membrane may be responsible, at least partially, for the decreased shell quality of eggs from heat-stressed hens. 相似文献
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10.
1. A multi-breed experiment was conducted with 25 commercial and traditional lines of laying fowl to determine the extent of between-breed genetic variation for adult body weight, sexual maturity, rate of lay, egg weight and egg composition to 55 weeks of age. The genetic variability for bone strength and eggshell strength was determined at 55 weeks of age and a comparison of commercially selected and traditional breeds was performed. 2. The proportion of the total variation that was associated with breed or line of origin was high (> 0.8) for body weight, sexual maturity and shell colour; moderately high (0.4 to 0.7) for rate of lay, early and late egg weight, weights of egg yolk, albumen and shell at 55 weeks; and low (< 0.4) for egg weight at 42 to 45 weeks, albumen quality and the number of egg inclusions. 3. There were no detectable differences between breed within category (traditional and commercial lines) for rate of lay, and estimates of breed variation for egg weight and egg components were substantially decreased within category compared with the overall analysis. 4. Commercial lines displayed earlier sexual maturity, greater rates and persistency of lay, and higher egg weights at earlier (32 to 35 weeks) and later (52 to 55 weeks) ages. At 55 weeks, the larger eggs from commercial birds contained more albumen of higher quality and paler yolks of similar weight to those from traditional breeds. The relative weight of the eggshell was similar in both categories. 5. There was considerable genetic variation between commercial lines for bone density and a moderate proportion of genetic variability for bone strength. Commercial lines had very weak bones compared with traditional lines but there was relatively little genetic variation for eggshell strength. The results suggest that eggshell quality is maintained in genetically selected lines at the expense of bone strength and bone radiographic density. 相似文献
11.
The effects of lindane on laying hens 总被引：1，自引：0，他引：1
Feeding lindane, in capsule form, to laying hens at a rate equivalent to 100 mg/kg food for 1 or 2 weeks had little effect on egg production. Longer periods of feeding resulted in a 20 to 30% decrease in the rate of egg production. When treatment was stopped after 4 weeks, the birds recovered and egg production returned to its original rate within a month. The production of flocks treated for 6 weeks or longer became permanently depressed since some birds went out of lay and failed to resume production when the treatment was terminated. Egg shell thickness, egg and yolk weight and hatchability were not significantly affected by the treatment. 相似文献
12.
Three experiments were performed to determine the effect of feeding time on shell quality and oviposition time in broiler breeders. Mean eggshell thickness was increased significantly by 3.5 microm (approximately 1%) per h delay in feeding time when hens were housed in individual cages. However, eggshell thickness was not significantly affected by feeding time when birds were housed on litter floors. Mean oviposition time was delayed relative to lights on by 5 min per h delay in feeding time. Egg weight was not significantly affected by feeding time, suggesting that differences in shell thickness and oviposition times were not due to increased oviducal transit times. Producers who wish to implement delayed feeding may have to turn lights on earlier than usual to compensate for delayed oviposition times. 相似文献
13.
本实验旨在探讨绍兴鸭剩余采食量(RFI)与生产性能及蛋品质之间的关系。测定300只绍兴鸭410~470日龄的采食量、体重、平均蛋重、蛋品质,计算出剩余采食量与料蛋比,并分析剩余采食量与生产性能及蛋品质的相关性。结果显示:绍兴鸭平均采食量、平均蛋重、体重、体增重、料蛋比、剩余采食量分别为198.8 g/d、73.0 g、1500.9 g、2.5 g/d、2.7、3.5 g/d;低剩余采食量组的剩余采食量、采食量以及料蛋比极显著低于高剩余采食量组;相关性分析表明,剩余采食量与采食量和料蛋比呈极显著正相关(P<0.01);采食量与平均蛋重、体重呈极显著正相关(P<0.01),与料蛋比呈极显著负相关(P<0.01),与体增重呈显著正相关性(P<0.05);蛋品质分析结果表明,高剩余采食量组仅蛋黄色泽水平显著高于低剩余采食量组;相关性分析表明,剩余采食量与蛋品质各指标间均无显著相关性。本试验结果表明,以剩余采食量为蛋鸭选育指标是可行的,且选育低剩余采食量的鸭子能显著降低采食量,提高饲料效率,且不改变产蛋重及蛋品质。 相似文献
14.
1. Performance traits were measured on 1908 Japanese quail and egg quality traits assessed on 1800 eggs at 10?wk of age. 2. Genetic and phenotypic correlations were estimated using a bivariate animal model with restricted maximum likelihood using ASREML software. 3. Body weight at different ages showed positive genetic correlations with egg weight and most of the internal egg quality traits, whereas their genetic correlations with eggshell thickness, eggshell strength and eggshell percentage were negative. 4. Genetic correlations of age at sexual maturity and egg number with most of external and internal traits were negative. 5. It was concluded that selection for higher body weight will result in heavier and better quality eggs. Because of the negative genetic correlation between BW and egg shell quality, a selection index including BW and eggshell strength would be the best breeding strategy for genetic improvement of egg quality in Japanese quail. 相似文献
15.
[目的]研究鸡蛋暗斑对蛋品质及其抗氧化能力的影响。[方法]从饲喂同种日粮、饲养环境相同、同日龄褐壳蛋鸡同一批次所产的褐壳蛋中,用灯光照射法挑选出24枚典型正常蛋、24枚典型暗斑蛋进行试验,并分别对正常蛋和暗斑蛋进行蛋品质、蛋黄抗氧化指标的测定及比较。[结果]蛋品质比较:暗斑蛋与正常蛋相比,其蛋形指数、蛋壳强度、蛋重、哈氏单位、蛋白高度、鸡蛋等级、蛋黄颜色、蛋黄重、蛋壳重、蛋清重、蛋壳厚度、蛋黄比重、蛋壳比重、蛋清比重均差异不显著(P>0.05);暗斑蛋蛋壳颜色极显著深于正常蛋(P<0.01)。抗氧化指标比较:暗斑蛋蛋黄的总抗氧化能力(T-AOC)显著低于正常蛋蛋黄的总抗氧化能力(P<0.05),暗斑蛋蛋黄的丙二醛(MDA)含量与正常蛋蛋黄的丙二醛含量相比差异不显著(P>0.05)。[结论]与正常蛋相比,暗斑蛋的蛋壳颜色较深,总抗氧化能力较差。 相似文献
16.
《The Journal of Applied Poultry Research》2014,23(1):59-70
The shell of the egg is essential in providing shape to the egg and ensuring safe packaging of the internal contents; however, shell defects have been shown to increase the risk of microbial contamination of eggs. Eggs were collected from commercial cage and free-range flocks at the ages of 25, 35, 45, 55, 65, and 75 wk. From each collection per flock, 30 eggs were processed for the eggshell and egg internal quality determination, 30 eggs for cuticle estimation, 30 eggs for mammillary layer ultrastructural features scoring, and 60 eggs for egg microbial enumeration. Translucency score and shell reflectivity were significantly higher in free-range eggs and increased with flock age in both production systems. Egg weight, shell weight, percentage shell, shell thickness, albumen height, Haugh unit, and yolk color were higher for cage eggs. The amount of cuticle was higher in cage eggs and fluctuated with flock age in both production systems. For the mammillary layer ultrastructural variables, a significant effect of production system and flock age was observed for early fusion, Type A bodies, and Type B bodies, whereas aragonite, depression, erosion, and hole were rarely observed. Variability of mammillary cap size, the incidence of poor mammillary cap quality, incidence of late fusion, alignment, Type A bodies, Type B bodies, and cubic cone formation were greater in the free-range versus cage system and increased with flock age in both production systems. The incidence of confluence and early fusion were greater in cage eggs and decreased with age in both production systems. Significantly lower total microbial load was observed for cage compared with free-range eggs, but the overall bacterial load recorded in this study was low. It can be concluded that cage eggs were better in overall quality when directly compared with free-range eggs. 相似文献
17.
为研究缠丝鸭蛋和普通鸭蛋在蛋品质及营养成分之间的差异,本试验随机选取300日龄左右鸭产的缠丝鸭蛋和普通鸭蛋各50枚,分别测定其蛋重、蛋壳厚度、蛋壳强度、蛋壳颜色、蛋白高度、蛋形指数、蛋黄色泽和哈氏单位等蛋品质性状及粗蛋白质、粗脂肪、钙、磷、锌和铁等营养成分含量。结果表明,与普通鸭蛋相比,缠丝鸭蛋的蛋重、蛋壳厚度、蛋壳颜色、蛋壳强度和蛋形指数差异均不显著(P>0.05),而蛋白高度、蛋黄色泽和哈氏单位极显著高于普通鸭蛋(P<0.01);蛋白质、钙、锌、铁含量较高,脂肪、磷含量较低。提示,缠丝鸭蛋蛋品质优于普通鸭蛋,营养物质含量比普通鸭蛋更丰富。 相似文献
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种蛋品质是影响种鸡性能的重要因素。本研究对大恒优质肉鸡S01、S05、S06和S08四个品系父母代种蛋的蛋重、蛋形指数、蛋壳强度、蛋壳厚度、蛋白高度、哈氏单位、血肉斑率等蛋品质指标进行了研究分析。结果显示：四个品系在蛋重、蛋形指数、蛋白高度和哈氏单位等指标方面有显著差异（P〈0．05）。S08品系蛋重最大,S05、S06居中,S01最小;S08品系蛋形指数最大,S01、S06居中,S05最小;S05、S06品系蛋白高度、哈氏单位显著优于S01,与S08没有显著差异。蛋壳厚度、蛋壳强度和血肉斑率各品系之间没有差异（P〉0．05）。结果表明大恒优质肉鸡父母代四个品系的蛋品质较好,品系间存在明显差异,可为进一步的品系改良提供很好的素材。 相似文献
20.
1. Broiler breeders were given a 3-h increase in photoperiod to 11 h at 20 week and then a series of increases to reach 16 or 17 h either immediately after the initial increment or in 30-min, 1- or 2-h increments starting at various ages after peak rate of lay. Controls were maintained on 11 h from 20 weeks. Changes in plasma LH concentration (after 7 d) were measured in birds that had been transferred to 11 or 16 h at 20 weeks and given further increases in photoperiod at 41 or 61 weeks of age. 2. Birds that were transferred to 16- or 17-h photoperiods, irrespective of when and how the maximum photoperiod was reached, had inferior rates of lay between 52 and 60 weeks of age to birds maintained on 11 h from 20 weeks. However, the 11-h birds laid more eggs on the floor and produced a larger number of cracked and dirty eggs, resulting in similar numbers of settable eggs. 3. Although transferring birds from 11- to 16-h photoperiods at 41 weeks of age significantly increased plasma LH concentration, there was no effect on egg production during the ensuing 12 d. None of the other increases in photoperiod significantly increased plasma LH, whether given at 41 or 61 weeks. 4. It is concluded in broiler breeders, that increases in photoperiod applied during the laying period, from 11 or 16 h, have little or no effect on LH secretion, do not compensate for age-related declines in egg production, and adversely affect rate of lay. 相似文献