Characteristics of Egg-related Traits in the Onagadori (Japanese Extremely Long Tail) Breed of Chickens

Abstract

The Tosa-no-Onagadori (briefly Onagadori) is one of the native Japanese chickens that is characterized by extremely long tail feathers in males, and thus designated as a "Special National Natural Treasure" of Japan. We investigated the timing of sexual maturity of the Onagadori and White Leghorn hens and the quality of the first 10 eggs laid by these young hens to obtain basic information for reproducing the Onagadori efficiently and also to assess their usefulness as research material for quantitative trait loci (QTL) analysis of egg-related traits. Onagadori and White Leghorn hens reached sexual maturity at around 237 and 192 days of age, respectively. The repeatability, a genetic parameter, of 22 egg quality traits including weight, size, and color of the eggshell, albumen, and yolk was estimated to be 0.14-0.61 and 0.15-0.83 for the Onagadori and White Leghorn, respectively, which indicated the stability of Onagadori eggs as well as the White Leghorn and further suggested that young Onagadori hens lay eggs with suitable quality to produce more offspring from their earliest egg laying stage. Principal component analysis with the 22 egg quality traits revealed five principal components explaining 79.70% of the total phenotypic variance. One-way ANOVA revealed differences between the two breeds in PC2 (heights of the albumen and yolk, size of the whole egg, and weights of the whole egg and albumen), PC3 (eggshell color), and PC4 (weight, thickness, and strength of the eggshell), which means that besides cultural assets the Onagadori is also valuable for QTL analysis of egg-related traits, for which phenotypic differences are quite useful for detecting corresponding loci.

Genotype affects free amino acids of egg yolk and albumen in Japanese indigenous breeds and commercial Brown layer chickens

“…Since Nagoya and Yakido breeds are used for mating to produce Jidori commercial chickens, their eggs are continuously available in the Livestock Research Institute. Previous works revealed that hens from the other Japanese fancy breeds, Oh-Shamo and Onagadori, produce some differences in egg characteristics in comparison with White Leghorn ( Goto et al., 2015 ; Goto and Tsudzuki, 2017 ). Therefore, Japanese indigenous chickens will have a potential to express distinct feature of egg traits.…”

Genetic effect on free amino acid contents of egg yolk and albumen using five different chicken genotypes under floor rearing system

“…Many kinds of chickens have extreme phenotypic characteristics such as body size, feathers, growth, eggs, meat, and behavior. For example, the Japanese indigenous chicken breeds of "Onagadori" has extremely long tail feathers in male [3,4], while the weight of male "Oh-Shamo" reaches 4-6 kg [3,5,6]. Thus, the indigenous chickens have a large potential for studying genetic and phenotypic diversity [7].…”

Metabolomics Approach Reveals the Effects of Breed and Feed on the Composition of Chicken Eggs

“…On the other hand, significant breed effects were found on eggshell colors (lightness, redness, and yellowness), with RIR hens laying darker brown eggs than AUS hens. White to brown variation in eggshell color is a heritable quantitative trait [9,10,11], and eggshell colors of Oh-Shamo, White Leghorn, Hy-line Brown, and Onagadori chickens were reported [33,34,35]. Comparing this study to previous work, eggs appear to decrease in color from brown to white in the order of Hy-Line Brown > RIR > Oh-Shamo > AUS > Onagadori > White Leghorn [33,34,35].…”