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.     

不同品种鸡蛋品质及营养成分比较研究

随机抽取32~36周龄的罗曼褐鸡、淮南鸡、闽中麻鸡的正常鸡蛋各100枚,分别测定蛋品质及其营养成分。结果表明:罗曼褐鸡蛋重最大,闽中麻鸡次之,淮南鸡最小,三者之间均有极显著差异(P<0.01);蛋形指数、哈氏单位、粗蛋白质含量及钙、磷水平三者无显著差异(P>0.05);闽中麻鸡的蛋黄颜色最深,淮南鸡的蛋壳颜色最浅,且鸡蛋中水分含量也最低(P<0.05);罗曼褐鸡的蛋白比例明显高于淮南鸡、闽中麻鸡(P<0.05);淮南鸡的蛋壳比例、蛋比重、蛋壳厚度均高于罗曼褐鸡和闽中麻鸡;淮南鸡和闽中麻鸡的蛋黄比例、粗脂肪含量、胆固醇含量都显著高于罗曼褐鸡(P<0.05);罗曼褐鸡蛋的血、肉斑率(52.5%)显著高于闽中麻鸡(25%,P<0.05)和淮南鸡(22.5%,P<0.05)。     

Physical and chemical quality of ostrich eggs during the laying season

1. Fifteen ostrich females were monitored for a full breeding season. At 30, 70, 110, 150 and 210 d from the beginning of laying, one egg per female was taken to the laboratory to assess its physical and nutritive characteristics. 2. The average length was 15.4 cm, while the width was 12.9 cm. Average shell thickness ranged from 2.20 mm at the equator to 2.24 mm at the small pole. The three principal components of the egg (albumen, yolk and shell) amounted to 57.1, 23.3 and 19.6%, respectively. None of the above variables, despite showing some significant differences between sampling periods, showed a clear trend linked to the laying season. 3. In contrast, the dry matter of the albumen showed a correlation with the sampling period, increasing from 11-1% in the first period to 12.0% in the last. The crude protein content ranged from 47.7 to 48.2%, the fat from 43.8 to 44.2% and the ash between 5.2 and 5.5% of dry matter. 4. The fatty acid composition of the yolk showed the presence of C18:1 (from 122.0 to 136.4 mg/g), followed by C16:0 (from 40.8 to 46.0 mg/g), C18:0 (from 19.2 to 21.2 mg/g) and C18:2 (from 17.1 to 19.6 mg/g). The content of cholesterol/g of yolk was between 10.6 and 10.9 mg. 5. In conclusion, compared with the hen's egg, the ostrich egg has similar chemical and nutritive characteristics, but a higher unsaturated/saturated fatty acid ratio and lower cholesterol content.     

锗的理化性质及其对畜禽的营养生理功能

大量试验研究表明,锗及锗化合物具有促生长、抗癌、抗氧化、清除自由基、刺激造血系统功能、抑菌及提高免疫力等广泛的生物学活性。本文就锗的理化性质、锗的分布和代谢、锗的生物学功能及其存在问题等方面进行了全面论述。     

Physical characteristics and chemical composition of Lesser Rhea (Pterocnemia pennata) eggs from farmed populations

1. Eggs from 4 farmed populations of Lesser Rhea (Pterocnemia pennata) were studied to determine their physical and chemical characteristics. 2. None of the physical variables (weight of whole egg, yolk, albumen and shell; proportion of yolk based on egg content; proportion of shell based on entire egg weight; volume; density) showed significant differences between populations. 3. Among chemical variables, moisture, both saturated fatty acids (palmitic 16:0 and stearic 18:0), one monounsaturated fatty acid (palmitoleic 16:1), and one polyunsaturated fatty acid (arachidonic 20:4), did not differ between populations, whereas other variables (protein, lipid and ash contents; fatty acids: oleic 18:1, linoleic 18:2, linolenic 18:3; PUFA; PUFA/SFA; cholesterol) differed significantly.     

Eggshell of the domestic guinea fowl

1. Physical characteristics of eggs of the domestic guinea fowl, Numida meleagris galeata, were measured and compared with those of its wild counterpart and with other birds using allometric relationships.

2. The shell thickness increased and the area density of pores decreased from the blunt to the pointed end of the egg. During incubation, shell thickness decreased, but the shell diffusive conductance to water vapour (G_H2O) remained constant.

3. Fresh egg mass (m₀), length and breadth of the egg, G_H2O and specific water vapour conductance, spG_H2O (G_H2O per g of m₀ ), were affected by the age of the laying flock.

4. Eggs of the domestic guinea fowl were bigger and heavier than eggs of the wild one.

5. Allometry showed that guinea fowl eggs differ from those of the other birds by their greater shell thickness and density of pores. However spG_H2O was normal, the thickness of the shell being compensated for by a greater density of pores for gas exchanges.     

Lighting and mortality rates in domestic fowl

1. Data from intermittent and conventional lighting trials were analysed to investigate the effect of daily illumination upon mortality during the laying period and in 49‐d‐old broilers.

2. Iiveability in laying hens was improved by the use of intermittent lighting: the degree of improvement was proportional to the reduction in daily illumination achieved by the intermittent programme.

3. The reduction in mortality with intermittent lighting in laying hens was not the result of intermittent lighting per se. Intermittent regimens which did not reduce daily illumination did not reduce mortality.

4. Mortality in both conventionally‐lit laying hens and 49‐d old‐broiler chickens increased with photoperiod.     

从品种审定看中国家禽育种业

从最早品种审定公开发表的1999年到2009年,中国家禽品种审定工作进行了11个年头,这11年里,中国共审定了31个家禽品种（配套系）,以平均每年9％-10％的速度递增,这是中国家禽行业种源建设的重大成果。     

Water uptake by eggs of mallards and guinea fowl

The cuticle is the principal barrier to water uptake by the eggs of mallard, guinea fowl and the domestic fowl. The fat present in the cuticle of mallard eggs makes a large contribution to repelling water dropped on to the shell but only a small contribution to resisting water movement into eggs exposed to hydrostatic pressure. Although the thickness of the shells of the eggs of the birds mentioned above varied extensively, there was no obvious correlation of the length of the pore canal with the amount of water taken up by an egg.     

Osteochondrosis in six breeds of slaughter pigs

Summary

The severity and extent of osteochondral lesions have been examined, macroscopically, radiographically as well as histopathologically, in six different breeds of pigs (Belgian Landrace (B), Duroc (D), Dutch Landrace (N), Dutch Yorkshire (G), Hampshire (H) and Piétrain (P)). In these pigs three different levels of feeding were used.

Duroc pigs had significantly more severe lesions in the fore limbs than Dutch Landrace (N), Dutch Yorkshire (G), Hampshire (H) and Piétrain (P) pigs, while Belgian Landrace pigs (B) had significant more severe lesions than Dutch Yorkshire (G) pigs. The differences between breeds related more to the degree of severity of the lesions in the articular surfaces of the distal humerus and proximal radius‐ulna and in the distal ulnar growth plate than to the presence of the lesions per se. In the hind limbs Belgian Landrace pigs (B) had significantly more severe osteochondral lesions than all other breeds, while Dutch Landrace pigs (N) had significantly more severe lesions than Duroc (D), Dutch Yorkshire (G), Hampshire (H) and Piétran (P) pigs.

Pigs with the highest growth rate showed sginificantly more severe osteochondral lesions in the distal ulnar growth plate and in the medial fe,moral condyle than pigs with a more restricted growth rate.     

Osteochondrosis in six breeds of slaughter pigs

Summary The severity and extent of osteochondral lesions have been examined, macroscopically, radiographically as well as histopathologically, in six different breeds of pigs (Belgian Landrace (B), Duroc (D), Dutch Landrace (N), Dutch Yorkshire (G), Hampshire (H) and Piétrain (P)). In these pigs three different levels of feeding were used. Duroc pigs had significantly more severe lesions in the fore limbs than Dutch Landrace (N), Dutch Yorkshire (G), Hampshire (H) and Piétrain (P) pigs, while Belgian Landrace pigs (B) had significant more severe lesions than Dutch Yorkshire (G) pigs. The differences between breeds related more to the degree of severity of the lesions in the articular surfaces of the distal humerus and proximal radius-ulna and in the distal ulnar growth plate than to the presence of the lesions per se. In the hind limbs Belgian Landrace pigs (B) had significantly more severe osteochondral lesions than all other breeds, while Dutch Landrace pigs (N) had significantly more severe lesions than Duroc (D), Dutch Yorkshire (G), Hampshire (H) and Piétran (P) pigs. Pigs with the highest growth rate showed sginificantly more severe osteochondral lesions in the distal ulnar growth plate and in the medial fe,moral condyle than pigs with a more restricted growth rate.     

Acceleration of hatching in the domestic fowl

Eggs of the domestic fowl were stimulated from the 19th day of incubation until hatching by artificial clicks at one of two rates which, in the quail, have been found effective (1) in accelerating and (2) in retarding the development and hatching time of the foetus. The time at which each stimulated egg hatched was determined and compared with those of three control eggs kept in the same incubator. All four eggs were kept as far apart from each other as possible. Of the ten eggs given accelerating stimulation all hatched before the mean hatching time of the controls and nine before any of the controls. Of those given retarding stimulation seven hatched after the mean hatching time of the controls but only five after all the controls.

It is concluded that hatching can be advanced in the domestic fowl if the egg is given the appropriate stimulation, but that there is no evidence of the retardation of hatching under the conditions provided.     

Physical characteristics and chemical composition of Greater Rhea (Rhea americana) eggs from wild and captive populations.

1. Eggs from wild and captive populations of Greater Rhea (Rhea americana) were studied to determine their physical and chemical characteristics. 2. Significant differences were found among populations in almost all chemical parameters studied, whereas within physical parameters only shell weight (as a proportion of the entire egg) and density showed differences. 3. Eggs from wild populations had the highest protein and linolenic acid and the lowest total lipid contents, while cholesterol levels of these eggs and of those from the largest captive area were the lowest.     

A diallel crossing experiment with two breeds of laying fowl

Light Sussex and Brown Leghorn flocks were concurrently bred pure and crossed in both directions for 6 years in an experiment to test for genetic interactions (“nicking”) between individual sires and dams. The traits measured in survivors to 450 days of age were (i) egg production, 126–250 days, (ii) egg production, 250–450 days, (iii) egg production, 126–450 days, (iv) mature egg weight, (v) age at sexual maturity and (vi) pullet weight at 18 weeks.

There was little response to selection in the primary trait, egg production to 450 days. Crossbreds showed a degree of heterosis in averages of egg production and there were consistent reciprocal differences between crossbreds in egg weight and pullet weight. It was impossible to distinguish between sex linkage and maternal effects in the determination of these differences.

Analyses of variance were complicated by the breed difference and by heterogeneity of variances, but yielded little evidence of interaction in egg production either between sires and breed of dams or between dams and sires. Some significant interactions were noted in egg weight and pullet weight. A weighted covariance technique yielded high positive correlations between purebred and crossbred sire family means, and confirmed that genetic interactions were unimportant. Thus reciprocal recurrent selection would not have been advantageous for improving egg production of crossbreds from the two flocks.     

Ectopic pulmonary cartilage and bone in domestic fowl

The occurrence and histological appearance of ectopic pulmonary cartilage and bone in domestic fowl was investigated. Its incidence was shown to vary in different strains of birds. The structures may occur in newly hatched chicks and are similarly present in birds maintained on diets containing bonemeal and diets without it. They could not be experimentally induced by bronchial insufflation of fine bone particles. Previous theories of their genesis are discussed and it is concluded that they do not originate from either inhaled dietary bonemeal or disease processes but are probably abnormal embryonic induction of mesenchyme or cartilaginous germ cells displaced from adjacent bronchi.     

Incidence of salmonellae in domestic fowl in Slovakia from 1971 to 1980

In flocks with latent infections, 2724 strains of salmonellae (19 serotypes) were isolated from the birds. The following species were represented as follows: S. gallinarum-pullorum (65.08%), S. typhimurium (9.10%), S. bareilly (6.90%), S. enteritidis (2.38%) and S. agona (1.98%). In the foci of salmonelloses 893 strains of salmonellae (19 serotypes) were isolated. The highest representation was found in the S. gallinarum-pullorum (54.20%), S. typhimurium (24.53%), S. bareilly (7.72%), S. choleraesuis (2.29%), S. enteritidis (1.68%), S. infantis (1.54%) and S. anatum (1.23%). Post-mortem examination resulted in recording 15 887 strains of salmonellae (41 serotypes). The following were represented by the largest proportions: S. gallinarum-pullorum (26.62%), S. typhimurium (25.20%), S. bareilly (18.93%), S. infantis (7.20%), S. enteritidis (4.62%), S. agona (3.51%), S. choleraesuis (3.17%), S. anatum (2.19%), S. lille (1.54%) and S. bredeney (1.16%).     

四川6个山羊品种(群体)乳的生化组成研究

用MilkScan-1340A/B型全自动综合乳质测仪和SDS-PAGE分别测定了成都麻羊、南江黄羊、金堂黑山羊、建昌黑山羊、北川白山羊、波尔山羊和波尔山羊(♂)与成都麻羊(♀)杂交一代羊乳的常规成分和乳蛋白组分。结果表明,乳中干物质波尔山羊为(160·57±8·61)g/L,显著高于成都麻羊和南江黄羊(P<0·05),其余品种(群体)间差异不显著;波尔山羊乳脂和乳蛋白含量分别为(60·62±2·81)g/L和(46·73±3·15)g/L,显著高于成都麻羊、南江黄羊和金堂黑山羊(P<0·05),其余品种(群体)间差异不显著。乳蛋白组分中,α-乳清蛋白、β-乳蛋白、免疫球蛋白的相对含量在山羊品种(群体)间差异均不显著;酪蛋白相对百分含量波尔山羊为(67·57±1·45)%,显著低于成都麻羊和南江黄羊(P<0·05)。