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.

Nutrient Reserve Dynamics of Breeding and Molting Brant

The Auk ◽  
1984 ◽  
Vol 101 (2) ◽  
pp. 361-370 ◽  
Author(s):  
C. Davison Ankney
Keyword(s):  
Body Weight ◽  
Northwest Territories ◽  
Egg Production ◽  
Muscle Protein ◽  
Nutritional Stress ◽  
Egg Laying ◽  
Branta Bernicla ◽  
Nutrient Reserve ◽  
Males And Females ◽  
Nutrient Reserves

Abstract I collected 150 Brant (Branta bernicla) at East Bay, Southampton Island, Northwest Territories, Canada, in 1979 and 1980 to evaluate how much these birds rely on reserves of fat, protein, and calcium during egg production, incubation, and the subsequent wing molt. Egg laying resulted in decreases in body weight and nutrient reserves of females. These decreases could have accounted for all of the fat but only 70% of the protein in an average clutch. Neither males nor females had sufficient reserves when incubation began to enable them to fast during that period. Only 11% and 22% of the energy required by males and females, respectively, could have been derived from their reserves during incubation. Brant evidently did not use body reserves to obtain nutrients for feather growth during wing molt. Rather, molting males and females accumulated muscle protein, which supports my hypothesis that wing molt is not a nutritional stress for waterfowl.

INFLUENCE OF TEMPERATURE AND HUMIDITY ON LONGEVITY, FECUNDITY, AND RATE OF INCREASE OF THE MITE TYROPHAGUS PUTRESCENTIAE (SCHRANK) (ACARINA: ACARIDAE) REARED ON MOLD CULTURES

1961 ◽  
Vol 39 (6) ◽  
pp. 869-876 ◽  
Author(s):  
I. Rivard
Keyword(s):  
Egg Production ◽  
Food Products ◽  
Egg Laying ◽  
Oviposition Period ◽  
Tyrophagus Putrescentiae ◽  
Influence Of Temperature ◽  
Adult Females ◽  
Rate Of Increase ◽  
Temperature And Humidity

Adult females of Tyrophagus putrescentiae (Schrank), a mite that infests stored food products, were reared individually on mold cultures at all combinations of five temperatures and four humidities. A definite diminution in life usually occurred with increase in either temperature or humidity, and the oviposition period was the most affected. Total egg-production and rate of laying were highest at 72.5° F and 90% R.H., and both generally decreased with an increase in temperature or decrease in humidity from these values. Peak of egg-laying, however, was reached sooner at higher temperatures but egg-production was maintained at relatively high levels for shorter periods. Rate of increase was greatest and approximately the same at 90% R.H. within the range 72.5° to 81.5° F.

Long continued oestrogen administration to fowls

1962 ◽  
Vol 4 (2) ◽  
pp. 257-267 ◽  
Author(s):  
Alan W. Greenwood
Keyword(s):  
Egg Production ◽  
Previous Experiment ◽  
Egg Laying ◽  
Short Term ◽  
Carcinogenic Agent ◽  
Wide Range ◽  
Term Administration ◽  
Effective Level ◽  
Development And Differentiation ◽  
Males And Females

Long continued administration of a substance (dienoestrol diacetate) having oestrogenic properties as a dietary additive to chickens from hatching over a period of 4½ years resulted in:—(1) an early, transient, hindrance to sexual development in both males and females,(2) a wide range of individual variation in response to the drug, shown i n the degree of feminisation of the plumage in males, and certain characteristics associated with egg laying in the females,(3) shell defects and related early embryonic deaths which could be attributed to an interference by the drug with development and differentiation of the oviduct.The birds were maintained throughout the experiment under two contrasting environments ‘natural’ and ‘constant’. In the former group two birds developed tumours (one a typical adenocarcinoma) while four of the ‘constant’ birds had adenocarcinomata on examination post-mortem. The incidence of the condition was much lower than that encountered in a previous experiment and suggested that the oestrogen employed was not of itself a carcinogenic agent.The primary function of the ovary was apparently unaffected and egg production to normal expected levels in both environments was attained.The disproportionally high number of hens dying with inspissated yolk i n the oviduct and/or free yolk in the abdomen emphasises the possible effect of oestrogen on oviduct development and activity.The danger of increasing the ‘load’ of oestrogens to susceptible individuals destined for breeding stock (and not short term administration of oestrogens for growth and ‘finishing’ of birds for slaughter) is referred to, and also its wider application were natural and synthetic oestrogenic substances in the diet to exceed a non-effective level.

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.

Nutrient-reserve dynamics of semiarid-breeding White-faced Whistling Ducks: a north-temperate contrast

2004 ◽  
Vol 82 (7) ◽  
pp. 1082-1090 ◽  
Author(s):  
Scott A Petrie ◽  
Kevin H Rogers
Keyword(s):  
Egg Production ◽  
Egg Laying ◽  
Body Protein ◽  
Protein Requirements ◽  
Semiarid Environments ◽  
Plant Matter ◽  
Low Protein ◽  
Nutrient Reserve ◽  
Males And Females ◽  
Endogenous Reserves

Little is known about the nutrient-reserve dynamics of waterfowl that breed in semiarid environments. Breeding White-faced Whistling Ducks, Dendrocygna viduata (L., 1766), were collected on the Nyl River floodplain, South Africa, during 1992–1993 and 1995. Mass of major lipid (wet skin + visceral fat + abdominal fat) and protein (breast muscle + leg muscle + gizzard) deposits and organs of males and females were evaluated in relation to sex and reproductive stage. Both sexes arrived at breeding areas with large lipid reserves and did not store additional lipid after arrival. Stored reserves enabled females to begin laying shortly after arrival, an important adaptation to ephemeral wetlands in semiarid environments. Females catabolized at least 37 g of lipid and 27 g of body protein during rapid follicular growth and ovulation. This accounted for 87% of their total lipid and 60% of their protein requirements during egg laying. Males catabolized at least 19 g of lipid between arrival and the end of laying. Although diets of breeding White-faced Whistling Ducks are high in fat, females satisfied most of their lipid requirements for clutch formation from endogenous reserves. Female White-faced Whistling Ducks can reproduce despite their reliance on a relatively low protein diet, and this suggests that they efficiently assimilate amino acids from plant matter. Biparental care apparently decreases the reliance of female White-faced Whistling Ducks on stored nutrients after ovulation, thereby allowing greater allocation of stored nutrients to egg production.

scholarly journals Influence of Age and Sex on the Blood Biochemical Constituent Values of Broiler Breeders During the Egg-Laying Stage

2021 ◽  
Author(s):  
Marcelo Sebastião Rezende ◽  
BELCHIOLINA BEATRIZ FONSECA ◽  
Paula Fernanda Sousa Braga ◽  
Ednaldo Carvalho Guimarães ◽  
Antonio Vicente Mundim
Keyword(s):  
Egg Production ◽  
Serum Levels ◽  
Egg Laying ◽  
Broiler Breeders ◽  
Broiler Breeder ◽  
Blood Biochemical ◽  
Calcium Phosphorus ◽  
Males And Females ◽  
Calcium And Phosphorus ◽  
Age And Sex

Abstract This study aimed to evaluate the influence of age and sex on the blood biochemical constituents of broiler breeders during the egg production stage. The analysis was performed in an industrial broiler breeder farm, and blood samples were collected from males and females at five different ages. At most ages, females had higher values of total proteins, albumin, globulins, triglycerides, cholesterol, glucose, calcium, phosphorus, Ca/P (calcium and phosphorus)ratio and gamma-glutamyltransferase (GGT). The values of uric acid, aspartate aminotransferase (AST), creatine kinase (CK), and alkaline phosphatase (PAL) were higher in males. The lowest protein values were found at 28 and 60 weeks old. The mean albumin values were significantly higher at 44 and 52 weeks old in males and females. A trend of increasing globulin values ​​with increasing age up to 52 weeks old was observed. Although calcium and phosphorus did not vary according to age, the Ca/P ratio was lowest at 36 weeks old. Comparing the means of both sexes, the AST and GGT values were significantly higher in 60-week-old birds. The highest serum levels of CK occurred at 28 and 52 weeks old. The physiological levels of serum biomarkers presented in this work are important for evaluating productivity performance, welfare, and disease indication in breeding flocks.

scholarly journals Mathematical Models for Egg Production in Broiler Breeder Hens

2016 ◽  
Vol 16 (4) ◽  
pp. 1185-1198 ◽  
Author(s):  
Agnieszka Otwinowska-Mindur ◽  
Małgorzata Gumułka ◽  
Joanna Kania-Gierdziewicz
Keyword(s):  
Mathematical Models ◽  
Egg Production ◽  
Goodness Of Fit ◽  
Reproductive Potential ◽  
Egg Laying ◽  
Broiler Breeders ◽  
Egg Weight ◽  
Broiler Breeder ◽  
Breeder Hens ◽  
Broiler Breeder Hens

Abstract Broiler breeders hens (meat-type hens) have lower reproductive potential than laying-type hens. Statistical models for predicting potential laying pattern are important for economically optimal breeding strategy of egg production in a poultry flock. The aim of the study was to find the most suitable function for describing the egg-laying rate and egg weight during the broiler breeders’ production period and to characterize laying pattern in groups of hens with different egg production. The following four mathematical models were used: gamma, Narushin-Takma, logistic-curvilinear, and compartmental. The daily recorded egg production data from 100 broiler breeder hens were used. Hen-weekly egg production was described using laying rate during successive weeks after reaching sexual maturity (26 weeks of age) and daily recorded egg weight. On the basis of the total number of eggs laid (NEggs), groups of hens with low (21%), intermediate (52%), and high (27%) egg production were created. The differences between the goodness-of-fit criteria values (AIC, R2 MSE) were small, with all the examined models having the same quality of curve fitting for egg-laying rate and egg weight. The logistic-curvilinear model was able to fit well both egg-laying rate and egg weight of the whole broiler breeder hens’ flock, and also when hens were divided into three egg production groups. This model could be considered in a long-term prediction of the reproductive potential in the commercial management. Moreover, the presented model could be useful in the research on different reproduction parameters of individual hens.

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 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.

Sign in / Sign up

Export Citation Format

Share Document