Effect of long-term selection for egg production on eggshell quality of Japanese quail (Coturnix japonica)

Genetic parameters of egg quality traits in long-term pedigree recorded Japanese quail.

This work was carried out at Sakha Poultry Production Research Station, Animal Production Research Institute, Ministry of Agriculture, during two successive generations in order to estimate the correlated response in egg production, egg quality and hatch traits to selection for body weight at 12 weeks of age in El-Salam chicken strains. Traits under taken were body weight, egg number, egg weight, egg mass, egg quality, fertility. Heritability, genetic and phenotypic correlations among studied traits were estimated.
The means of body weight at 12 week of age in El-Salam chicken strain in the base, first and second generations for males were 868.3, 903.6 and 942.9 g and for females were 838.6, 868.3 and 881.3g for selected line, respectively. Moreover, males and females in the selected line were heavier than corresponding birds in the control one for all generations.
After two generations selected for body weight, selected line was significantly higher body weight than control line by 85.4 and 33.6g in average means 9.8% and 4.0% superiority for male and female respectively.
 Selection to the weight of the body lead to the delayed age at sexual maturity, as well as increased body weight at sexual maturity and the period until the first ten eggs.
 Means of egg number and feed conversion were significantly reduced by generations. Moreover, egg weight and egg mass for selected line were significantly heavier than those of the control one.
 As generational succession caused significant improvements on Haugh units, it decreased egg shape index, shell thickens, albumen and yolk percentages. Furthermore, egg shape index and shell percentage were significantly (P<0.05) affected by lines. Also, data showed no significant interactions between generations and lines on all of tested egg quality traits.
 Reproductive performance as fertility and hatchability percentages were significantly (P≤0.05) reduced by -2.9 vs. -0.6% after progress two generation of selection, but not affected by lines separately or as combination with generations.
 Heritability estimated for body weight at 12 week of age were 0.67 based on sire variance component (h2s).
 Negative genetic and phenotypic correlations were found between body weight at 12 week of age with egg number, egg mass, fertility, hatchability, egg shape index, yolk%, shell% and shell thickens, while the positive effect were found for body weight at sexual maturity, age at sexual maturity, the period until the first 10 eggs, egg weight, feed conversion, albumen % and Hough unit.

https://jappmu.journals.ekb.eg/article_52984_a4d97d0c1526346c5a8ebd66bbca774c.pdf

EFFECT OF SELECTION FOR BODY WEIGHT ON EGG PRODUCTION, EGG QUALITY, FERTILITY AND HATCHABILITY TRAITS in EL-SALAM CHICKEN STRAIN IN EGYPT

The current study was aimed at exploring the relationship between egg physical parameters that can be evaluated before incubation without egg breakage and hatchability of chick embryos. Eggs from laying hens of the White Leghorn (WL), Rhode Island White (RIW) and Rhode Island Red (RIR) lines were examined using a ranking system for analysing influence of egg parameters on hatchability. Specifically, eggs were subdivided into three groups whose non-destructive measurement values were: (i) within the mean ± standard deviation (?), (ii) mean plus ?. As a result, the smaller WL and RIW eggs, where values of weight, volume, surface area, length and maximum breadth were < mean minus ?, appeared to be more successful at hatching than the bigger ones. Hatchability of the more ‘round-shaped’ WL and RIW eggs, whose shape index was 0·76?0·80, tended to be higher. Effect of egg-specific gravity on hatchability varied in different layer strains, and genetic background seemed to be an essential factor determining relationship between hatchability and other egg characteristics. The RIW eggs of larger weight with a relatively small surface area appeared to have decreased hatchability, supposedly due to insufficient gas exchange of embryos.

Relationship between hatchability and non-destructive physical measurements of chicken eggs

Hatchability is of considerable economic importance for all hatcheries and therefore must be given appropriate attention in breeding programs for commercial layers. The variability between and within strains will tell us whether reproductive performance can be improved by selection within specific lines. The aim of this study was to analyse the genetic variation of hatchability and correlations with production traits. Data collected from two pure-bred female lines (LSL) at 45-46 weeks of age were used. Estimated heritabilities were low (h² = 0.13 and 0.15) for fertility, but moderately high (h² = 0.27 and 0.30) for hatch of ‘fertile’ eggs (eggs transferred at 18 days). Hatchability was negatively correlated with egg weight (r g = -0.43 to -0.52) and albumen height (r g = -0.25 to -0.42). Favourable correlations were found with egg production (rg = -0.01 to +0.28), percentage yolk (r g = +0.08 to +0.39) and some shell quality traits like shape index and breaking strength (r g = +0.14 to +0.32), but not with dynamic stiffness (r g = -0.08 to -0.17). Hatch of fertile eggs has sufficient genetic variation in these White Leghorn lines to expect improvement by within-line selection, especially if supported by a reduction in total egg weight and selection for higher egg production, yolk percentage and shell breaking strength.

/pdf/improving-hatchability-in-white-egg-layer-strains-through-3ywt0877mp.pdf

Improving hatchability in white egg layer strains through breeding

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

W. Icken

Author Tools

Chat about Author

Papers

Improving hatchability in white egg layer strains through breeding