QUANTITATIVE GENETICS OF FERTILITY. IV. CHROMOSOMES AFFECTING EGG PRODUCTION IN DROSOPHILA MELANOGASTER

1972 ◽  
Vol 14 (1) ◽  
pp. 147-156 ◽  
Author(s):  
Malcolm Fitz-Earle
Keyword(s):  
Drosophila Melanogaster ◽  
Quantitative Genetics ◽  
Egg Production ◽  
Inbred Lines ◽  
Egg Laying ◽  
Specific Chromosome ◽  
New Model ◽  
Rate Of Decline ◽  
Two Parameters

Chromosomal combinations of the X, 2 and 3 chromosomes were synthesized from two inbred lines of Drosophila Melanogaster. Egg production determinations over the productive lifetime of sibling matings from the lines were fitted to a new model of lifetime egg production. The two parameters in the model which had been shown to be essentially genetic were related to specific chromosome effects. Chromosomes X and 3 but not 2, influenced the rate of decline in oviposition α and the time of cessation of egg-laying tq. In addition, interactions of chromosomes 2 and 3 upon these parameters were detected. The chromosome or interaction between chromosomes which decreased α concomitantly increased tq and vice versa.

EFFECT OF THE SINGED LOCUS ON THE EGG PRODUCTION CURVE OF DROSOPHILA MELANOGASTER

1981 ◽  
Vol 23 (2) ◽  
pp. 327-336 ◽  
Author(s):  
Gonzalo Alvarez ◽  
Antonio Fontdevila
Keyword(s):  
Experimental Data ◽  
Drosophila Melanogaster ◽  
Theoretical Model ◽  
Egg Production ◽  
Egg Laying ◽  
Wild Type ◽  
Clear Effect ◽  
Total Lifetime ◽  
Female Genotype ◽  
Production Curve

Egg production curves of virgin and mated females of several genotypes at the singed locus of Drosophila melanogaster have been studied. Fitz-Earle's theoretical model (1971) for characterizing daily egg production has been used. In general, the model gave good fit to the experimental data. A clear effect of the female genotype is detected on the following parameters and derivations of the model: α, rate of decrease in egg production; tq, day of cessation of egg-laying, N(tmax), maximum egg production; and T(to,tq), total lifetime egg production. Homozygous snqr females present higher values of α and lower values of tq, N(tmax), and T(to,tq) than heterozygous and wild-type homozygous females. Egg-to-larva viability along female lifetime related with the different physiological stages of the egg-laying curve (increasing, maximum, and decreasing parts) has been also studied. Homozygous snqr females show low viability and decreasing with age compared to wild-type females. In some cases, different physiological stages of the egg production curve show characteristic egg-to-larva viability values.

QUANTITATIVE GENETICS OF FERTILITY. III. A NEW MODEL FOR INTERSTRAIN LIFETIME EGG PRODUCTION COMPARISONS

1971 ◽  
Vol 13 (4) ◽  
pp. 782-792 ◽  
Author(s):  
Malcolm Fitz-Earle
Keyword(s):  
Egg Production ◽  
Goodness Of Fit ◽  
Egg Laying ◽  
Least Squares Regression ◽  
Linear Least Squares ◽  
New Model ◽  
Maximum Production ◽  
Genetic Components ◽  
Rate Of Increase ◽  
Males And Females

A new model for use in theoretical and practical studies of egg production is derived: N(t) = (1−e−ξ(t–to))e−α(t–tq), where N(t) is the number of eggs laid on day t; ξ is the rate of increase in egg production; α is the rate of decrease in egg production; to is the day of initiation of egg-laying; tq is the day of cessation of egg-laying. Egg production curves for Drosophila melanogaster strains were fitted using non-linear least squares regression analyses such that all parameters in the model and their errors were generated simultaneously. The goodness-of-fit of the model to the observed data was precise. The experimental evidence showed that parameters α and tq were basically describing the genetic components of egg production in females whereas parameters ξ and to exhibited additional components, the interactions between males and females. Expressions derived from the model, tmax, the time of maximum production, N(tmax), the maximum production at this time and T(to,tq), the production over lifetime, gave results consistent with the observations.

scholarly journals QUANTITATIVE GENETICS OF FERTILITY II. LIFETIME EGG PRODUCTION OF DROSOPHILA MELANOGASTER—EXPERIMENTAL

Genetics ◽  
1970 ◽  
Vol 65 (2) ◽  
pp. 355-369
Author(s):  
I McMillan ◽  
M Fitz-Earle ◽  
L Butler ◽  
D S Robson
Keyword(s):  
Drosophila Melanogaster ◽  
Quantitative Genetics ◽  
Egg Production

Probiotics in the diets of laying quails

2020 ◽  
pp. 60-66
Author(s):  
O. Merzlyakova ◽  
V. Rogachyev ◽  
V. Chegodaev
Keyword(s):  
Bacillus Subtilis ◽  
Bacillus Licheniformis ◽  
Egg Production ◽  
Positive Impact ◽  
Hematological Parameters ◽  
Economic Effect ◽  
Egg Laying ◽  
Control Group ◽  
Egg Mass ◽  
The Cost

The efficiency of introducing probiotics based on strains of Bacillus subtilis, Bacillus licheniformis and their consortium in the amount of 150 g/t of feed into the diets of laying quails has been studied. The experiment lasting 182 days has been carried out on four groups of quails with 30 heads in each. The quails have been housed in the broiler battery in compliance with the required microclimate conditions. Quails of all groups have been received the main diet (compound feed) developed taking into account their age and physiological characteristics. The quails of the 1st, 2nd and 3rd experimental groups in addition to the main diet received probiotics (150 g/t compound feed) based on strains Bacillus subtilis, Bacillus licheniformis and their consortium, respectively. It has been found that feeding the laying quails of the consortium of strains Bacillus subtilis and Bacillus licheniformis had the most significant positive impact on their productive performance, it allowed to increase egg production by 7,81 %, egg laying intensity by 5,0 %, egg mass yield by 9,77 %, while reducing feed expenditures for 10 eggs by 13,35 %. The yield of hatching eggs has been increased by 7,03 %, hatchability of chickens from laid and fertilized eggs by 8,33 and 8,35 %, brooding waste decreased by 21,74 %. Hematological parameters of quails during the whole experiment were within the physiological norm. The economic effect calculated on the basis of data on the cost of compound feed, probiotics and the cost of sold eggs of quail laying was 14,56 % in the 3rd experimental group (in relation to the control group).

scholarly journals Proteomic Analysis Identifies Potential Markers for Chicken Primary Follicle Development

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1108
Author(s):  
Armughan Ahmed Wadood ◽  
Jingyuan Wang ◽  
Liping Pu ◽  
Qaisar Shahzad ◽  
Muhammad Waqas ◽  
...  
Keyword(s):  
Proteomic Analysis ◽  
Egg Production ◽  
Potential Role ◽  
Protein Localization ◽  
Follicular Development ◽  
Egg Laying ◽  
Follicle Development ◽  
Phosphate Binding ◽  
Primary Follicle ◽  
Mannose Metabolism

Follicles’ development in chicken imparts a major impact on egg production. To enhance the egg-laying efficiency, comprehensive knowledge of different phases of follicular development is a prerequisite. Therefore, we used the tandem mass tag (TMT) based proteomic approach to find the genes involved in the primary follicular development of chicken. The primary follicles were divided into two groups—small primary follicles (81–150 μm) and developed primary follicles (300–500 μm). Differential expression analysis (fold change > 1.2, p-value < 0.05) revealed a total of 70 differentially expressed proteins (DEPs), of which 38 were upregulated and 32 were downregulated. Gene ontology (GO) enrichment analysis disclosed that DEPs were intricate with cellular protein localization, the establishment of protein localization, and nucleoside phosphate-binding activities. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment pathway indicated the involvement of DEPs in different metabolic pathways such as glycolysis, pyruvate metabolism, galactose metabolism, and fructose and mannose metabolism. The current proteomic analysis suggested suitable markers such as Anxa2, Pdia3, and Capzb, which may serve as a potential role for primary follicle development. The present study provides the first insight into the proteome dynamics of primary follicle development and would play a potential role for further studies in chicken to improve egg productivity.

scholarly journals The Rate of Mutation and the Homozygous and Heterozygous Mutational Effects for Competitive Viability: A Long-Term Experiment With Drosophila melanogaster

Genetics ◽  
2001 ◽  
Vol 158 (2) ◽  
pp. 681-693 ◽  
Author(s):  
David Chavarrías ◽  
Carlos López-Fanjul ◽  
Aurora García-Dorado
Keyword(s):  
Drosophila Melanogaster ◽  
Minimum Distance ◽  
Deleterious Mutations ◽  
Regression Estimate ◽  
Term Experiment ◽  
Degree Of Dominance ◽  
Long Term Experiment ◽  
Rate Of Decline ◽  
Good Agreement

Abstract The effect of 250 generations of mutation accumulation (MA) on the second chromosome competitive viability of Drosophila melanogaster was analyzed both in homozygous and heterozygous conditions. We used full-sib MA lines, where selection hampers the accumulation of severely deleterious mutations but is ineffective against mildly deleterious ones. A large control population was simultaneously evaluated. Competitive viability scores, unaffected by the expression of mutations in heterozygosis, were obtained relative to a Cy/L2 genotype. The rate of decline in mean ΔM ≈ 0.1% was small. However, that of increase in variance ΔV ≈ 0.08 × 10-3 was similar to the values obtained in previous experiments when severely deleterious mutations were excluded. The corresponding estimates of the mutation rate λ ≥ 0.01 and the average effect of mutations E(s) ≤ 0.08 are in good agreement with Bateman-Mukai and minimum distance estimates for noncompetitive viability obtained from the same MA lines after 105 generations. Thus, competitive and noncompetitive viability show similar mutational properties. The regression estimate of the degree of dominance for mild-to-moderate deleterious mutations was ∼0.3, suggesting that the pertinent value for new unselected mutations should be somewhat smaller.

scholarly journals Dual-Purpose Poultry in Organic Egg Production and Effects on Egg Quality Parameters

Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 897
Author(s):  
Marianne Hammershøj ◽  
Gitte Hald Kristiansen ◽  
Sanna Steenfeldt
Keyword(s):  
Egg Production ◽  
Egg Quality ◽  
Quality Parameters ◽  
Egg Laying ◽  
High Yield ◽  
Meat Production ◽  
Dual Purpose ◽  
Shell Quality ◽  
Egg Shell ◽  
Genotype A

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.

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