scholarly journals Body Size and Condition, Timing of Breeding, and Aspects of Egg Production in Eastern Kingbirds

The Auk ◽  
1986 ◽  
Vol 103 (3) ◽  
pp. 465-476 ◽  
Author(s):  
Michael T. Murphy
Keyword(s):  
Body Size ◽  
Body Condition ◽  
Egg Production ◽  
Egg Quality ◽  
Flight Muscle ◽  
Egg Laying ◽  
Female Size ◽  
Timing Of Breeding ◽  
Muscle Weight ◽  
Egg Weight

Abstract Variation in timing of breeding in Eastern Kingbirds (Tyrannus tyrannus) was correlated only weakly with external morphological characters, but was correlated positively and significantly with estimates of body size based on measurements of skeletons and muscle weights. Small females apparently held a reproductive advantage in being able to mobilize resources for reproduction before large females. Egg weight was independent of all measures of female size, but was directly and significantly (P = 0.03) correlated with standard flight muscle weight, a relative index of body condition. Egg size was thus a function more of female body condition than size. On average, shell, yolk, and albumen comprised 5.6%, 21.9%, and 72.5%, respectively, of fresh egg weight. Dry albumen and dry shell increased proportionately with fresh egg weight, but dry yolk did not. Total protein, lipid, and energy of fresh eggs all increased proportionately with weight. Comparison of egg composition and standard flight muscle weight of laying females indicated moderate positive, although nonsignificant, correlations between body condition and measures of egg quality, especially lipid content. Based on post-egg-laying body composition and nutrient requirements for the production of one egg, it appeared that most females probably could have laid an additional egg almost solely from body reserves. Clutch size thus appears to be independent of body condition.

Genetic variation of egg production traits in purebred and crossbred laying hens

1999 ◽  
Vol 68 (3) ◽  
pp. 433-439 ◽  
Author(s):  
B. Besbes ◽  
J. P. Gibson
Keyword(s):  
Egg Production ◽  
Egg Quality ◽  
Genetic Correlations ◽  
Egg Laying ◽  
Production Traits ◽  
Egg Weight ◽  
Partial Dominance ◽  
Dominance Variance ◽  
Stressful Environment ◽  
Model Approach

AbstractHeritabilities, dominance variation and genetic correlations (rpc) among purebred and crossbred performance were estimated for egg production (number of eggs produced between 19 and 25, 26 and 38 and 26 and 54 weeks of age) and egg quality traits (average egg weight, shell strength) in four generations of two nucleus lines of egg-laying chickens and their cross, all reared in similar environments. The within-line genetic parameters were estimated using method R applied to an animal model (approach 1) and tilde-hat approximation to restricted maximum likelihood applied to a sire-dam model (approach 2). The genetic correlation between purebred and crossbred performance as well as the crossbred heritabilities were estimated based on a multivariate sire-dam model accounting for all relationships. For egg numbers and shell strength, the purebred heritabilities were low to moderate (0·12 to 0·42). They were higher when estimated under an additive model (0·25 to 0·51) but, in general, lower than the crossbred heritabilities. For egg weight, the heritabilities were always high (0·6 to 0·7). The ratio of dominance variance to total genetic variance varied between 11 and 36% with approach 1 and 5 and 56% with approach 2, indicating a large partial dominance for egg number traits and shell strength but also the difficulty of accurately estimating the dominance variance. For these traits, the estimates of the correlation between purebred and crossbred performance, rpc, were quite high (0·8 to 0·94) which contradicts the theory that traits with larger dominance and/or difference between purebred and crossbred heritabilities present lower rpc. These high rpc estimates, coupled with the absence of obvious heterosis, indicate little advantage to be gained from use of crossbred data in genetic improvement, where pure lines and crossbreds are reared in a similar non-stressful environment.

scholarly journals Feeding time under performance and eggs quality of quails in production

2018 ◽  
Vol 19 (1) ◽  
pp. 136-143 ◽  
Author(s):  
Isabelle Bossolani Fernandez ◽  
Lígia Fátima Lima Calixto ◽  
Karoll Andrea Alfonso Torres-Cordido ◽  
Marina Jorge de Lemos ◽  
Cristina Kimie Togashi ◽  
...  
Keyword(s):  
Egg Production ◽  
Egg Quality ◽  
Egg Laying ◽  
Egg Mass ◽  
Feeding Time ◽  
Feed Conversion ◽  
Egg Weight ◽  
Coturnix Coturnix ◽  
Randomized Design

SUMMARY In order to evaluate the performance and egg quality of quails on different time feeding, One hundred ninety two Japanese quail (Coturnix coturnix japonica) at 24 weeks of age were distributed in a completely randomized design with two replications and twelve treatments eight birds each. The treatments consisted of two different times of feeding at 6h and 16h. The performance was evaluated by the feed intake (g/bird/day), egg production (%), egg mass (g), feed conversion per egg mass (kg/kg ), feed conversion per dozen eggs (kg/dz) and viability (%). The egg quality was evaluated by the eggshell thickness (mm), percentage of albumen, yolk percentage and average egg weight (g). The feeding time at 16h favored the performance of Japanese quails at 26 and 34 wk of age considering egg production, egg mass and average egg weight. Thus, it is recommended to feed the quails at times that coincide with the highest egg laying intensity, which ranges from 16 to 19h.

scholarly journals Effect of agave oligofructose feed on egg production from laying hens

2018 ◽  
pp. 7108-7112
Author(s):  
Ivónn Yanine Chávez-Mora ◽  
David Román Sánchez-Chiprés ◽  
Jorge Galindo-García ◽  
Miguel Ángel Ayala-Valdovinos ◽  
Theodor Duifhuis-Rivera ◽  
...  
Keyword(s):  
Egg Production ◽  
Laying Hens ◽  
Egg Quality ◽  
Egg Laying ◽  
Feed Additive ◽  
Egg Weight ◽  
Feed Supplementation ◽  
Treatment Groups ◽  
Alternative Feed

Objective. To determine egg production in laying hens treated with oligofructose from agave. Materials and methods. Eighteen weeks old Hy-line W-36 hens (n=300) were distributed randomly into 3 treatment groups: no feed supplementation (control) or feed supplementation with 0.1% of 0.2% oligofructose from agave (OFA). Hens were monitored from development until 30 weeks of egg laying. Results. A significant (p<0.05) increase in the percent of egg-laying hens as well as increased in egg weight and egg quality occurred in hens from the OFA treatment groups relative to the control hens. Significantly lower levels (p<0.05) of fecal putrescine were observed in hens from the OFA treatment groups. Conclusions. The oligofructose from agave may be used as an alternative feed additive in laying hens.

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.

scholarly journals Fish by-product meal in diets for commercial laying hens

2017 ◽  
Vol 39 (3) ◽  
pp. 273
Author(s):  
André Ferreira Silva ◽  
Frank George Guimarães Cruz ◽  
João Paulo Ferreira Rufino ◽  
Waldo Mateus Plácido Miller ◽  
Nathália Siqueira Flor ◽  
...  
Keyword(s):  
Production Cost ◽  
Egg Production ◽  
Laying Hens ◽  
Polynomial Regression ◽  
Egg Quality ◽  
Feed Conversion ◽  
Egg Weight ◽  
Feed Cost ◽  
Randomized Design ◽  
Completely Randomized Design

 This study aimed to evaluate the increasing levels (0, 1, 2, 3 e 4%) of fish by-product meal in diets for laying hens on performance, egg quality and economic analysis. A total of 160 Dekalb White hens with 52-wk old were distributed in a completely randomized design with five treatments and four replicates of eight birds each. The experiment lasted 84 days divided into four periods of 21 days. Estimates of fish by-product meal levels were determined by polynomial regression. Differences (p < 0.05) were detected for all variables of performance, in egg weight, yolk and albumen percentage, yolk and albumen height, feed cost and production cost, in which the inclusion of fish by-product meal in the diets showed better results. It can be concluded that fish by-product meal can be used in diets for hens as alternative feed, with better results in egg production, feed conversion, egg weight, yolk-albumen ratio and a reduction in feed cost and production cost. 

scholarly journals Heterosis effect in hybrid laying hens

2014 ◽  
Vol 30 (2) ◽  
pp. 303-311 ◽  
Author(s):  
P. Hristakieva ◽  
M. Oblakova ◽  
M. Lalev ◽  
N. Mincheva
Keyword(s):  
Sexual Maturity ◽  
Egg Production ◽  
Live Weight ◽  
Egg Laying ◽  
Production Traits ◽  
Egg Weight ◽  
Group V ◽  
Paternal Line ◽  
Group I ◽  
Heterosis Effect

The new original egg laying lines T, P and N selected at the Institute of Agriculture - Stara Zagora were used. Hybrid ?? ? ??, ?? ? ?? crosses were obtained and used for paternal line. Thereafter, the following breeding schedule of paternal and maternal lines was applied: Group I - (?????)? ?N?; group ?? - (?????)? ?N?; group ??? - ???N?; and group ?V - ???N?. The production traits of original and hybrid birds were recorded: live weight at the age of 8 and 18 weeks, age of sexual maturity in days, 150 days egg production, average egg weight - at 2-week intervals until end of lay; livability, heterosis effect. The live weights of hybrids at 8 and 18 weeks of age were statistically significantly lower compared to original lines. The values of heterosis for this parameter were negative for all four hybrid combinations. The earliest beginning of egg lay occurred in (?????) ? ?N? (162.08 days of age) and ???N? (163.11 days of age). The relative (%) heterosis for age of sexual maturity of studied hybrid combinations had moderate to low negative values. Average egg weights of hybrids were higher and the values of heterosis - positive for all four groups varying from 0.97% to 1.63%. The average 150 days egg production was lower in purebred lines compared to hybrids. The highest average 150 days egg production was determined in ???N? hybrids - 142 eggs. The heterosis effect for egg production in hybrids was significant.

scholarly journals Effects on egg production and quality of supplementing drinking water with calcium and magnesium

2021 ◽  
Vol 51 (4) ◽  
pp. 469-476
Author(s):  
X.J. Yi ◽  
A. Rehman ◽  
R.W. Akhtar ◽  
A. Abbas ◽  
K. Hussain ◽  
...  
Keyword(s):  
Drinking Water ◽  
Egg Production ◽  
Laying Hens ◽  
Egg Quality ◽  
Production Performance ◽  
Egg Weight ◽  
Calcium And Magnesium ◽  
Eggshell Colour ◽  
Haugh Unit

This study was conducted to appraise the effects on egg quality and production performance of laying hens when drinking water was supplemented with calcium (Ca) and magnesium (Mg). A total of 384 (64-week-old) Hy-line Brown laying hens were assigned at random to four treatments, which consisted of CON: unsupplemented drinking water; T1: drinking water + 2 mg/L Ca + 250 mg/L Mg; T2: drinking water + 4 mg/L Ca + 510 mg/L Mg /10 L; and T3: drinking water + 5 mg/L Ca and 760 mg/L Mg. The experiment lasted six weeks. Water intake increased linearly in week 1 with the rising levels of Ca and Mg in the drinking water. Increasing the Ca and Mg levels improved eggshell strength (week 2 (P =0.01), week 5 (P =0.01), and week 6 (P = 0.03), and eggshell thickness (week 6) (P =0.02) and reduced the rate at which eggs were broken (week 4) (P =0.01). The supplemental Ca and Mg did not affect egg production, egg weight, Haugh unit, albumen height, eggshell colour, and yolk colour compared with CON. Nor did they influence the Haugh unit and albumen height after storing for 1, 5, 10 and 15 days. In conclusion, adding Ca and Mg to the drinking water increased the thickness and strength of the eggshells.

scholarly journals Effect of protein and energy levels in a constant ratio supplemented with methionine and lysine on performance of layers and on egg quality.

1980 ◽  
Vol 28 (1) ◽  
pp. 29-35
Author(s):  
A.R. El Boushy ◽  
L.G.M. van Gils ◽  
M.C. Papadopoulos
Keyword(s):  
Feed Intake ◽  
Crude Protein ◽  
Egg Production ◽  
Laying Hens ◽  
Egg Quality ◽  
Energy Levels ◽  
Metabolizable Energy ◽  
Constant Ratio ◽  
Feed Conversion ◽  
Egg Weight

Twenty groups of 36 laying hens in individual cages were fed on one of 5 diets in which the energy:protein ratio was constant. Diets 1 to 5 had crude protein 12.0, 12.9, 14.0, 15.0 and 16.0% and metabolizable energy 8.71, 9.57, 10.27, 11.10 and 11.70 MJ/kg. From 24 to 64 weeks old, egg production of hens given diets 1 to 5 was 71.46, 71.31, 72.51, 71.13 and 69.99%, respectively. Corresponding values of mean egg weight, weekly feed intake and efficiency of feed conversion were 60.51, 60.47, 61.11, 61.02, 61.07 g; 157.16, 147.56, 142.03, 130.37, 126.72 g; 3.674, 3.460, 3.262, 3.031, 3.014 kg feed/kg egg, respectively. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Effects of a short laying rest on postrest egg production and egg quality

1993 ◽  
Vol 2 (5) ◽  
pp. 437-445
Author(s):  
Tuomo Kiiskinen ◽  
Hilkka Hakatie
Keyword(s):  
Mass Production ◽  
Feed Efficiency ◽  
Egg Production ◽  
Egg Quality ◽  
Live Weight ◽  
Egg Mass ◽  
Whole Grain ◽  
Egg Weight ◽  
Egg Shell ◽  
Production Period

Two factorial trials, each including three commercial laying hybrids, were conducted to study the effects of a short laying rest on postrest performance of hens and on egg quality. A total of 1800 hens laying at 65% on an average (70 wks of age) were subjected to one of the following treatments: no rest (control, C) or feeding only whole-grain barley (WB) or fasting (F, Trial 1 only) until the rate oflay dropped to 0%, after which the birds were returned to the previous all-mash diet. The second laying period was six months. Egg production of the WB and F hens ceased within one week on an average and the birds were out of production for 10 days. Laying intensity during the second production period did not differ significantly between the treatments in each trial, but egg weight and daily egg mass production increased as a result of the rest treatments. The laying rest procedures reduced feed intake, improved feed efficiency and increased live weight significantly. Egg shell and albumen quality traits were significantly better in the laying rest groups than in the controls. Significant differences in performance and egg quality between the hybrids were mainly ascertained in Trial 2. The results suggest that a short laying rest is a feasible means of improving egg quality towards the end of the laying period. It can be accomplished successfully by feeding whole-grain barley.

scholarly journals Effects of Incubation Conditions and Offspring Sex on Embryonic Development and Survival in the Zebra Finch (Taeniopygia Guttata)

The Auk ◽  
2005 ◽  
Vol 122 (4) ◽  
pp. 1239-1248 ◽  
Author(s):  
Helen E. Gorman ◽  
Kate J. Orr ◽  
Aileen Adam ◽  
Ruedi G. Nager
Keyword(s):  
Embryonic Development ◽  
Body Condition ◽  
Egg Quality ◽  
Good Condition ◽  
Taeniopygia Guttata ◽  
Egg Laying ◽  
Male And Female ◽  
Embryo Mortality ◽  
Offspring Fitness ◽  
Offspring Sex

AbstractSuboptimal conditions during embryonic development can affect offspring fitness. Both egg quality and incubation behavior can affect hatching success, hatching mass, and subsequent offspring performance. These effects may differ between male and female offspring. We manipulated the prebreeding body condition of Zebra Finches (Taeniopygia guttata), using diets of different protein content. To separate possible effects on egg quality of parental body condition and incubation conditions, we did a cross-fostering experiment. We analyzed embryo survival and hatching mass with respect to body condition of the egg-laying parent, body condition of the incubating foster parent, and offspring sex. Embryos were not affected by the condition of the egg-laying parent. Eggs incubated by parents in better condition suffered less embryo mortality than those incubated by parents in poorer condition, but only when overall embryo mortality was low. Hatching mass was also affected by the incubating foster parent’s body condition. And hatchlings incubated by parents in good condition were heavier than those incubated by parents in poor condition. Female hatchlings from late-laid eggs were heavier, in comparison with the size of the egg from which they hatched, than female hatchlings from earlier-laid eggs. No such effect was found for males. Therefore, male and female embryos may differ in their sensitivity to suboptimal conditions during embryonic development. These results suggest that parental body condition during incubation can affect offspring fitness.Efectos de las Condiciones de Incubación y el Sexo de las Crías sobre el Desarrollo Embrional y la Supervivencia en Taeniopygia guttata

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