TY - JOUR
T1 - Dual-Purpose Poultry in Organic Egg Production and Effects on Egg Quality Parameters
AU - Hammershøj, Marianne
AU - Kristiansen, Gitte Hald
AU - Steenfeldt, Sanna
PY - 2021/4
Y1 - 2021/4
N2 - Egg laying genotypes have been selected for generations due to their high yield and eggquality, resulting in efficient feed utilization and low body weight; hence, they are not suitable formeat 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 orderto avoid euthanasia of male day-old chicks has intensified. The aim of the present study is to evaluatepotential dual-purpose genotypes for their egg quality compared to a representative egg layinggenotype. Three dual-purpose genotypes with divergent characteristics were evaluated: genotypeA 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 comparedto a control genotype D, which was an egg layer. Eggs were collected six times during the period of21–54 weeks of hen age, i.e., a total of 1080 shell eggs were analyzed. Examined parameters wereweights of egg, shell, yolk, and albumen, by calculating their relative proportions. Shell quality wasassessed by shell strength, shell stiffness, and shell thickness. Yolk quality was determined as yolkcolor and inclusions of blood and meat spots, and albumen quality was evaluated in terms of pH anddry matter (DM) content. The egg layer genotype produced the smallest eggs with least blood andmeat spot inclusions compared to that produced by the three dual-purpose genotypes. Shell qualitywas superior for the layer genotype. However, the experimental genotype A laid eggs of comparableshell quality, albumen DM, and yolk weight, but also with the darkest and most red-yellow coloredyolk. 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.
AB - Egg laying genotypes have been selected for generations due to their high yield and eggquality, resulting in efficient feed utilization and low body weight; hence, they are not suitable formeat 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 orderto avoid euthanasia of male day-old chicks has intensified. The aim of the present study is to evaluatepotential dual-purpose genotypes for their egg quality compared to a representative egg layinggenotype. Three dual-purpose genotypes with divergent characteristics were evaluated: genotypeA 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 comparedto a control genotype D, which was an egg layer. Eggs were collected six times during the period of21–54 weeks of hen age, i.e., a total of 1080 shell eggs were analyzed. Examined parameters wereweights of egg, shell, yolk, and albumen, by calculating their relative proportions. Shell quality wasassessed by shell strength, shell stiffness, and shell thickness. Yolk quality was determined as yolkcolor and inclusions of blood and meat spots, and albumen quality was evaluated in terms of pH anddry matter (DM) content. The egg layer genotype produced the smallest eggs with least blood andmeat spot inclusions compared to that produced by the three dual-purpose genotypes. Shell qualitywas superior for the layer genotype. However, the experimental genotype A laid eggs of comparableshell quality, albumen DM, and yolk weight, but also with the darkest and most red-yellow coloredyolk. 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.
KW - dual-purpose
KW - egg
KW - egg albumen
KW - egg weight
KW - genotype
KW - layer hens
KW - quality
KW - shell strength
KW - yolk color
UR - http://www.scopus.com/inward/record.url?scp=85105004234&partnerID=8YFLogxK
U2 - 10.3390/foods10040897
DO - 10.3390/foods10040897
M3 - Journal article
C2 - 33921822
SN - 2304-8158
VL - 10
JO - Foods
JF - Foods
IS - 4
M1 - 897
ER -