Variation in the ovocalyxin-32 gene in commercial egg-laying chickens and its relationship with egg production and egg quality traits

2012 ◽  
Vol 43 ◽  
pp. 102-113 ◽  
Author(s):  
J. E. Fulton ◽  
M. Soller ◽  
A. R. Lund ◽  
J. Arango ◽  
E. Lipkin
2021 ◽  
Vol 51 (1) ◽  
Author(s):  
Mahmoud M. El-Attrouny ◽  
Mahmoud M. Iraqi

The current study investigated the influence of selection for increased egg production on external and internal egg quality traits over five generations in Japanese quail. A total of 4325 fresh eggs from 1326 females were collected each week during the egg-laying period to estimate heritability, genetic and phenotypic correlations, and correlated response of external and internal egg quality traits to selection for egg number (EN). The direct response to selection indicated an increase of 7.7 ± 0.27 eggs produced during the 90 days following production of the first egg. The correlated responses to selection indicated that selection for higher EN can be expected to increase EW and increase egg quality. Estimates of heritability ranged from 0. 11 to 0.35 for external egg quality traits and from 0.08 to 0.32 for internal egg quality traits. Estimates of the genetic correlations of EN with external and internal traits were positive, ranging from 0.09 to 0.25 and from 0.02 to 0.27, respectively. These estimates indicated few if any genetic antagonisms that would adversely affect selection response. However, eggshell thickness would not be expected to change as a result of selection for EN. Thus, the external and internal quality of Japanese quail eggs could be improved by selection for high egg production.


Author(s):  
C. Pandian ◽  
A. Sundaresan ◽  
A. V. Omprakash

The present study was conducted to assess the effect of supplementation of Multi-enzymes with lysophospholipids on production performance of pure line White Leghorn layers. Body weights before and after the experiment did not differ significantly across the experimental diets. Irrespective of the dietary treatments, the birds gained 3.83 per cent of live weight relative to its initial body weight. Mean per cent Hen housed egg production was significantly (Pis less than 0.05) higher in diet supplemented with 0.10 MEC-L than other groups. Mean egg weight and average daily feed consumption during 25 to 35 weeks of age indicated no significant effect of enzyme supplementation. Average daily feed consumption per bird in control, 0.05 % and 0.1% multi-enzyme supplemented groups was 108.13, 105.66 and 107.67 g respectively and birds offered control diet recorded numerically more feed intake than enzyme supplemented groups. Comparatively low feed per egg was observed in 0.10 per cent group followed by 0.05 per cent group which offers economic benefits than control diets. However, the egg quality traits between different dietary enzyme supplementation groups showed no significant difference.


2021 ◽  
pp. 101211
Author(s):  
R. Scappaticcio ◽  
J. Garcia ◽  
G. Fondevila ◽  
A.F. de Juan ◽  
L. Cámara ◽  
...  

Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 897
Author(s):  
Marianne Hammershøj ◽  
Gitte Hald Kristiansen ◽  
Sanna Steenfeldt

Egg laying genotypes have been selected for generations due to their high yield and egg quality, resulting in efficient feed utilization and low body weight; hence, they are not suitable for meat production. This imposes an issue for the male layer chicks, which are killed at one day old. Because of ethical and food waste concerns, the search for suitable dual-purpose genotypes in order to avoid euthanasia of male day-old chicks has intensified. The aim of the present study is to evaluate potential dual-purpose genotypes for their egg quality compared to a representative egg laying genotype. Three dual-purpose genotypes with divergent characteristics were evaluated: genotype A represented an experimental crossbreed based on a broiler type male and an egg layer female, genotype B was a pure breed, and genotype C was a crossbreed of a layer type. These were compared to a control genotype D, which was an egg layer. Eggs were collected six times during the period of 21–54 weeks of hen age, i.e., a total of 1080 shell eggs were analyzed. Examined parameters were weights of egg, shell, yolk, and albumen, by calculating their relative proportions. Shell quality was assessed by shell strength, shell stiffness, and shell thickness. Yolk quality was determined as yolk color and inclusions of blood and meat spots, and albumen quality was evaluated in terms of pH and dry matter (DM) content. The egg layer genotype produced the smallest eggs with least blood and meat spot inclusions compared to that produced by the three dual-purpose genotypes. Shell quality was superior for the layer genotype. However, the experimental genotype A laid eggs of comparable shell quality, albumen DM, and yolk weight, but also with the darkest and most red-yellow colored yolk. The two other dual-purpose genotypes produced eggs of low-medium quality. In conclusion, the genotype A could serve as dual-purpose genotype from an egg quality perspective.


2008 ◽  
Vol 53 (No. 8) ◽  
pp. 345-353 ◽  
Author(s):  
M. Sarica ◽  
S. Boga ◽  
U.S. Yamak

This study was conducted to investigate the effects of cage stocking density on egg yield, some egg quality traits and plumage condition in laying hens. Eighteen weeks-old 264 ISA-Brown pullets were divided into four cage density groups. The densities were 2 000, 1 000, 667 and 500 cm<sup>2</sup> per hen (by allocating 1, 2, 3 and 4 hens per cage; floor area 40 × 50 cm) with 48, 30, 24 and 21 replicate cages, totally 123 three-tier battery cages. During the experimental period from 18 to 53 weeks of age, all birds were provided illumination for 16 hours a day. The hens were fed a diet containing 11.7 MJ ME/kg and 180 g CP during the period of 18 to 40 weeks of age and 11.3 MJ ME/kg and 170 g CP during the period of 41 to 54 weeks of age. Feed and water were available for <I>ad libitum</I>. Egg yield, mortality, live weights at 50% egg production age and at the end of experiment, pecking related mortalities, some egg quality traits and plumage condition were recorded weekly. Hen-housed egg production, egg mass, viability, and live weights were significantly decreased by higher densities. Most of the egg quality traits were not affected by cage densities. Pecking related mortalities increased in cage densities of 667 cm<sup>2</sup> and 500 cm<sup>2</sup> per hen compared to the other densities (<I>P</I> < 0.05) while plumage scores were higher in all body parts of hens kept in cages of 2 000 cm<sup>2</sup> and 1 000 cm<sup>2</sup> densities compared to the higher densities. The results showed that brown laying hens should be kept in cages having 1 000–2 000 cm<sup>2</sup> densities in order to improve their welfare and performance.


2017 ◽  
Vol 52 (2) ◽  
pp. 138
Author(s):  
Nizam Hussain ◽  
S.T. Viroji Rao ◽  
M. Gnana Prakash ◽  
Daida Krishna ◽  
V. Venkateswara Reddy

2021 ◽  
Vol 43 (1) ◽  
pp. 224-232
Author(s):  
O. M. Agunbiade ◽  
P. A. Onimisi ◽  
J. J. Omage

Sorghum is the primary alternative feedstuff for corn in some developed countries in the production of poultry. Thus, four hundred and fifty 32 weeks old Lohmann Brown laying hens were used in a study to evaluate the effect of replacing maize with sorghum with or without enzymes supplementation, on egg laying performance and egg quality characteristics of laying hens. Birds were distributed randomly into six dietary treatments with three replicates per treatment, each replicate had 25 birds with uniform initial group weights. The treatments included maize without enzymes (T1); sorghum without enzymes (T2); as controls respectively, while T3, T4, T5, and T6 contained sorghum based diets with phytase, protease, G2G, and a combination of protease and G2G respectively. Laying performance, cost of production, and egg quality characteristics were determined for the period of the trial, 33-56 weeks of age of the birds. All data obtained were subjected to analysis of variance, using the completely randomized design (CRD) and significant differences among treatment means were compared using the Tukey test. Significant (p<0.05) differences were observed among dietary treatments but with no defined trend observed for egg production traits. Daily feed intake was significantly (p<0.05) higher in maize control diet compared to the other treatments. Diets supplemented with phytase (T3), protease (14), and combination of protease and roxazyme G2G (T6) had significantly (p<0.05) better feed conversion ratio with T3 having the lowest value of 4.01 compared to the other treatments. For feed cost/dozen egg (N), Kg feed/dozen eggs, income above feed cost at N30 per egg, and income above control treatment; phytase (T3), protease (T4), roxazyme 626 (T5), and protease + roxacyme G2G (T6) diets in this study showed better performance than the control. Sorghum diet without enzyme had significantly (p<0.05) least performance for egg number. Hen housed egg production (HHP) and hen day egg production (HDP) compared to the other treatments while sorghum diet with phytase had the highest value (60.12g/day) for average egg weight compared to the other treatments. Egg quality characteristics showed the best performance for dietary treatments supplemented with phytase (T3) in all the other parameters considered, apart from the albumen height, yolk diameter, and yolk index. It was concluded therefore, that sorghum with phytase and protease supplementations can be used in layers' diets as a substitute for maize for optimum egg production.


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