贵妃鸡蛋重和繁殖率关系探讨

选２８￣２９周龄贵妃鸡新产种蛋，按蛋重分４组作蛋重和繁殖率关系试验。结果表明，蛋重４１￣４５克组受精率，孵化率和健雏率分别达９８．１１％，９４．２３％和９７．９６％，极显著高于蛋重３０克和３１￣３５克组，４５克内蛋重与三率呈强正相关，小于３０克重组三率极显著低于其它组（Ｐ〈０．０１），试验说明贵刀鸡种蛋最佳蛋重为４１￣４５克，小于３０克的蛋不宜作种用。     

The relationship between yolk cholesterol and total lipid concentration throughout the first year of egg production in the domestic fowl

1. Variation of egg yolk cholesterol and total lipid concentration (mg/g wet yolk) throughout the first year of egg production for the domestic fowl is described.

2. Yolk cholesterol concentration decreases between 20 and 30 weeks of age, and then remains constant until 70 weeks of age. Yolk total lipid concentration increases to a maximum at 40 weeks of age before decreasing to its original value at 60 and 70 weeks of age.

3. Bird means for yolk cholesterol and total lipid concentration are negatively related at 20 weeks of age, and essentially independent for the remainder of the first year of egg production.

4. Variation for yolk cholesterol concentration between 30 and 70 weeks of age appears to be a consequence of differences in the proportion of cholesterol to other lipid components.

5. Uptake of plasma lipoproteins characteristic of the immature bird is likely to be responsible for the high yolk cholesterol concentration at 20 weeks of age.     

Changes in chicken egg white cystatin concentration and isoforms during embryogenesis

1. A higher concentration of cystatin, measured using the ELISA technique, was found in whites from unfertilised than fertilised eggs. 2. Up to day 8 of embryogenesis a decrease in cystatin concentration was observed, then at d 10 the concentration rose reaching the maximal value at d 14. 3. Immunoblot analyses showed both phosphorylated and nonphosphorylated isoforms of chicken cystatin in unfertilised egg white as well as in egg yolk and chicken serum. 4. Significantly lower immunostaining of the phosphorylated form after the 4th d of embryogenesis in egg white suggests its preferential transport into the yolk sac.     

The relationship between thickness and snapping strength in egg shells

The relationship between snapping strength and thickness was studied by filing away part of the egg shell in order to produce varying thicknesses. Thick shells of the ostrich, rhea and emu were used, because it was necessary to establish whether the new approach was worth while, before studying the thinner egg shells of the domestic hen which technically present a much more difficult problem.

It was found that when strips of shell of standard length and width were filed on the inside and snapped inwards, or filed on the outside and snapped outwards, then there was a rectilinear relationship between strength and the square of the thickness. When shells were filed on the inside and snapped outwards, the shell strength remained constant until quite a large fraction had been filed away, then the typical rectilinear relationship appeared. When shells were filed on the outside and snapped inwards, the removal of a little of the shell resulted in an increase in strength before the rectilinear relationship appeared. These results are discussed in relation to shell structure.

The use of concentrated hydrochloric acid to thin the shell was unsuccessful because it weakened the remaining shell far more than filing did. Treatment of the shell with boiling sodium hydroxide solution (10 per cent) either before or after filing, showed that the alkali is able to penetrate a complete shell as readily as it can penetrate into one which has been filed, and that the shell is weakened.     

Interrelationships between shell quality and egg production and egg and shell weights in white leghorn and white rock hens

Interrelationships between shell quality, production rate, egg and shell weights in relation to seasonal changes were compared in White Leghorn (WL) and White Rock (WR) hens. An increase in the average egg weight was observed in both breeds during the hot summer months. The weight and quality of the shell decreased gradually in eggs laid by WL hens, but increased in those from WR during the summer.

Significant negative correlation coefficients were found between shell quality and egg weight in only the WL, when analysed on the basis of individual averages for the entire experimental period and on weekly averages for the breed. No significant correlation was found between shell quality and production rate in WL hens. Great variabilities were obtained between individual birds regarding the correlations between shell quality and egg weight and between shell quality and production rate, when calculated on the basis of seasonal changes in both breeds.

Multivariate analysis, in which shell quality was correlated with the other variables in all combinations possible, supplied a wider explanation than the simple correlations calculated.

The differences between the two breeds are discussed.     

白鹅、籽鹅蛋重和蛋形指数对孵化率的影响

随机选取白鹅和籽鹅种蛋各251枚,测量蛋重和蛋形指数,研究蛋重和蛋形指数对种鹅孵化率的影响,结果表明:白鹅和籽鹅的蛋重分别为128.11±12.04 g,129.25±13.07 g;蛋形指数分别为1.457±0.065,1.457±0.068;白鹅和籽鹅的蛋重、蛋形指数无明显差异;白鹅和籽鹅种蛋孵化率随蛋重、蛋形指数的增加呈现先增大后减小的趋势,白鹅蛋重在131.16～144.88 g范围内,蛋形指数在1.387～1.496范围内种蛋孵化率最高;籽鹅蛋重在137.08～151.04 g范围内,蛋形指数在1.349～1.449范围内种蛋孵化率最高.     

The relationship between hatching egg weight and subsequent performance of broiler chickens

Small eggs constitute a high proportion of the eggs laid by pullets. The literature shows that chick hatching weight is strongly correlated with egg weight, but evidence on the influence of egg weight on hatchability and subsequent performance of chicks is less certain.

The aim of this experiment was to determine the profit returned at 12 weeks by broiler chickens hatched from eggs ranging in weight from 44 g. to 58 g. at one gram intervals and to determine how competitive and separate rearing might modify the relationship.

A total of 6000 eggs were collected during 10 days from a 28‐week‐old, broiler breeding flock and graded into the above mentioned egg weight classes. From these, a total of 3480 day‐old broilers were housed. Each egg weight class was equally represented and balanced for sex.

Hatchability and fertility showed no consistent trend with egg weight for eggs above 46 g., but below the 47 g. level there was a trend of declining fertility and hatchability.

A strong positive relationship was found between the weight of the chick at 1 day of age and egg weight for both males and females with no significant difference overall in body weight between the two sexes.

Body weight to 12 weeks was found to be strongly related to egg weight, in a linear fashion, though this influence declined with age.

There was a greater influence of egg weight on body weight at all ages in the separate rearing treatment compared with competitive rearing but this was not significant after 10 weeks.

Egg weight had an important bearing on body weight and profit at 12 weeks, but no effect on food conversion or mortality.

The increased profit over food costs per 100 day‐old chicks was found to be 52.75 cents for the separately reared birds respectively for each 3 g. increase in egg weight.     

The relationship between thickness and snapping strength in egg shells of the domestic fowl

Comparable pieces of egg shell from individual eggs of the domestic fowl were filed to give different thicknesses, they were then snapped and the relationship between snapping strength (S) and the square of the thickness (T ²) was studied.

For shells filed on the outside and snapped outwards or filed on the inside and snapped inwards there was a very significant relationship between S and T ². For shells filed on the inside and snapped outwards, the mammillary knobs made no contribution to strength and it was only after these had been filed off that a typical relationship between S and T ² developed.

Shells filed on the outside and snapped inwards gave very variable results in relation to the removal of the first layers of shell. In some cases the removal of a thin outer layer increased the strength and in other cases it decreased it and it was only later that a steady relationship between S and T ² developed.

In general the egg shells of the domestic fowl became weaker towards the inside of the shell.     

皖东牛发汗速率与血浆一氧化氮浓度关系的季节变化

选择健康状况良好、平均体重(457±16.6) kg的皖东公牛9头,分别在夏季(27～39℃)和秋季(18～25℃),通过测量牛舍环境温度、直肠温度(RT)、肩臀部发汗速率(SR)和血浆一氧化氮(NO)浓度,建立体感温度公式,揭示不同温湿度对皖东牛直肠温度的影响和血浆NO浓度与发汗速率的内在联系。结果:以直肠温度作为皖东牛对干球温度(DBT)和湿球温度(WBT)的反应指标,得到夏秋季节的体感温度(ET)公式分别为:ET=0.28DBT+0.72WBT和ET=0.51DBT+0.49WBT,表明随着温度的升高,湿球温度在体感温度公式中的影响比重加大。夏季NO浓度显著低于秋季(P0.01),肩臀部发汗速率显著高于秋季(P0.01)。结论:(1)南方夏季高温高湿环境下,随着环境温度的升高,干球对直肠温度的影响比重减小,湿球的影响比重加大;(2)发汗速率与血浆NO浓度呈现季节性变化:夏季发汗速率随温度的升高而升高,而血浆NO浓度递减;秋季血浆NO浓度、发汗速率随温度的降低而递减。     

猪胎盘效率与生长肥育性能的关系

采集77头纯种大白母猪的469个仔猪胎盘性状和生长性状资料．应用个体动物模型和MTDFREML，软件进行了遗传统计分析，估计了胎盘效率(初生重与胎盘重的比率)和遗传力及其与生长性状的遗传相关。结果表明，胎盘效率有较高遗传力0．46；胎盘效率与断奶重、达100kg日龄、日增重和背膘厚的遗传相关分别为0．03、-0．45、0．37和0．12，选择胎盘效率对生长性状的影响较小。     

On the relationship between the height of the thick albumen and the weight of eggs

Calculations from data of egg quality obtained at four Regional Experimental Farms for Poultry Husbandry and at the Central Institute for Poultry Research “Het Spelderholt” at Beekbergen, the Netherlands, support the conclusions advanced in recent American investigations that the uniform regression of Haugh (1937), which is used for the correction of the height of the thick albumen in relation to the egg weight (0.05 mm. per g. difference in weight), has no general validity. Only for fresh eggs at the beginning of the laying period was an average regression found which did not deviate significantly from the Haugh regression. Significant differences between farms and strain crosses were not established as long as exceptionally deviating circumstances were not considered. It was also found that as the laying period proceeded the Haugh correction factor for the height of the thick albumen in relation to the egg weight could have an adverse effect. The same conclusion is valid for stored eggs produced at the end, and probably at the beginning, of the laying period.     

The absence of a relationship between egg production and dominance in caged laying hens

1. The individual egg production of two strains of laying hen in colony battery cages was recorded from 20 to 72 weeks of age by feeding a different fat‐soluble dyestuff to each bird and then breaking open the eggs to determine the yolk colour and hence the identity of the hen that laid the egg.

2. Observations of agonistic behaviour and other pecking were made and the combs were examined for pecking damage on two occasions; each group of hens was hierarchically arranged in terms of these three measures, which were then taken as an indication of each hen's dominance.

3. The three measures of dominance correlated fairly well with each other, but none showed any relationship with egg production.     

蜂胶清除自由基能力与总黄酮含量和醇溶物含量的相关性

【目的】探讨蜂胶清除自由基的能力与总黄酮和醇溶物含量的相关性。【方法】选取16个不同地区的蜂胶,用超声波辅助乙醇浸提法提取,Fenton反应和邻苯三酚自氧化反应测定醇提液对羟自由基（·OH^-）和超氧阴离子自由基（·O2^-）的清除率,分光光度法和重量法测定总黄酮和醇溶物的含量。【结果】蜂胶醇提液清除·OH^-的能力与其总黄酮含量、醇溶物含量均存在极显著的正相关;清除·02-的能力与其总黄酮含量、醇溶物含量均不存在明显的相关性（r=0．119,P=0．66〉0．05）、（r=0．414,P=011〉0．05）。【结论】蜂胶中总黄酮和醇溶物含量的高低,并不能完全代表蜂胶清除自由基能力的强弱。     

微卫星标记与鸡蛋品质性状关系的研究

本试验分别对60周龄文昌鸡和新扬州鸡进行了蛋品质的测定,测定了8个性状为:蛋重、蛋壳重、蛋壳厚度、蛋壳强度、哈氏单位、蛋形指数、蛋黄重、蛋黄颜色。通过统计软件,对各蛋品质性状进行了相关分析,并通过选用20对微卫星标记,筛选出了与哈氏单位、蛋重有关的分子遗传标记。结果表明:与60周龄新扬州鸡的哈氏单位有关的标记为2号染色体上MCW239和4号染色体上的ADL260,与60周龄新扬州鸡的蛋重有关的标记为2号染色体上的ADL176和MCW239,与60周龄新扬州鸡蛋壳强度有关的标记Z染色体上的LEI229;而与60周龄文昌鸡哈氏单位相关的有2号染色体的的ADL176、MCW239和4号染色体的MCW240,与60周龄文昌鸡蛋重相关的是4号染色体上的标记LEI119,与60周龄蛋壳强度相关的标记为Z染色体上的MCW246和LEI229。     

Variation in egg yolk cholesterol concentration between and within breeds of the domestic fowl.

1. The pattern of variation for egg yolk cholesterol concentration between 5 commercial egg layer lines and a cross of Gallus domesticus is described. 2. Yolk cholesterol concentration in the cross was lower than in the lines, and 6.7% lower than the midparent value. 3. It is proposed that the reduced yolk cholesterol concentration of the cross may be a consequence of heterosis, although sex-linkage and/or maternal effects cannot be discounted. 4. The difference between the cross and parental lines is consistent with a physiological relationship between yolk cholesterol concentration and rate of egg production, but not between yolk cholesterol concentration and yolk weight.