The start of egg laying to own hens try influenced by genotype, nutritional looks standing and you will environmental standards. Local breeds (white eggshell breeds-Padovana and Polverara; tinted eggshell types-Pepoi, Ermellinata di Rovigo, Robusta Maculata and Robusta Lionata) regarding Veneto area, inside the North Italy, was in fact reared outdoors away from spring season (six days old; 6 WA) to help you fall and wintertime. The fresh new start of installing ranged depending on the reproduce (22–28 WA): only the shaded eggshell breeds become putting at the end of summer/start of fall, regarding the exposure out-of a decreasing absolute photoperiod, therefore the egg development lasted for almost all months. On 38 WA, fake white was slowly placed into the brand new photoperiod to get 14L:10D, and also at 42 WA, the half dozen types was in fact installing. To possess hens reared outside, affairs among ecosystem, looks opportunity and you may health standards should be thought about. The knowledge on active give and egg top-notch the fresh local reproduce hens are helpful with the handling of brand new wild birds and a sufficient supply of egg, for industry and for brooding all year long.
Abstract
The month of hatching and the rearing management, especially temperature and photoperiod, are important factors for pullets and hens reared outdoors. The yield performance and egg quality of dual-purpose chicken breeds from the Veneto region (Italy), Pepoi (PP), Ermellinata di Rovigo (ER), Robusta Maculata (RM) and Robusta Lionata (RL), with different adult body weights (ABW, kg, PP = 1.3; ER = 2.3, RM and RL = 3.1), were studied, using a factorial model (4 ? 2), considering breed and age (26–33 weeks, first age, summer–autumn, under decreasing natural photoperiod-on average, 12L:12D, and 42–53 weeks, second age, winter, under implemented photoperiod-14L:10D) as the main effects and interaction. The chicks hatched in spring, and they started laying at the end of summer/beginning of autumn. Significant ( p < 0.05)>
step one. Läs mer Introduction
Over the past pair years, need for twin-objective poultry breeds might have been broadening, for both biodiversity and you may ethical issues. Given the improvements in the hereditary developments to own produce abilities in hybrid hens carried out by several reproduction businesses all over the globe , biodiversity is currently among key standards regarding sustainability for as well as agriculture . The ethical effect on creature passion try a much deeper important question, which considers not only the new rearing criteria of your own wild birds however, plus its government. The newest men regarding eggs layer hybrids are killed just after hatching, as they do not carry out the important development and you will slaughtering quality asked towards the market . Additionally, crossbreed broilers inform you of a lot bodily trouble, which do not let them features high enough really-getting criteria, and you may 100 % free-diversity rearing assistance is actually increasing while they allow it to be chickens to better inform you its sheer behavior [step three,4]. During the Italy, this new Veneto area has actually a lengthy traditions off poultry reproduction, a few poultry types have been popular for almost all centuries, along with the middle of the very last century, some twin-purpose purebreds are made having fun with light- and brownish-eggshell breeds . The initial profile you to differentiates the fresh new types, according to its resource, ‘s the shade of new eggshell, because poultry genotypes has a special phylogenetic source, which have developed by themselves regarding the crazy Gallus genus just after domestication, and several system features disagree among them. Following category suggested by the Ghigi, into the 1905, the fresh home-based poultry breeds is going to be put into about three teams, centered on their morphological, physical and you will practical services . You will find types, which are including crazy Gallus genus, showing early gains and you can sexual maturity and a high production of egg with light eggshells. On the other hand, you’ll find types very different from insane Gallus , proving delay increases and sexual maturity, lower egg manufacturing having brown eggshells, and you can, regarding third classification, there are advanced breeds, labeled as dual-goal breeds, and this reveal advanced faculties, with additional similarity to the types from the earliest or 2nd classification . Indeed, it is known that breeds creating egg having white eggshells enjoys body development, a beneficial metabolic profile and you can physiology a great deal more suited to high eggs design than simply brown eggshell types. That it physiological reputation, better presented of the white eggshell hybrids [seven,8], suggests that the newest mineral consumption is employed for many of skeletal and you will growth of muscles till the start of putting following useful for eggs development, avoiding competition towards consumed diet ranging from human anatomy invention and you can egg development. More recently, knowledge, according to SNP assortment, genotyped of several chicken breeds and you will hybrids around the world to evaluate the new hereditary diversity ranging from and inside communities towards effective handling of poultry hereditary resources [9,10]. Differences in genetic diversity in population were found within extremely chose industrial covering traces and many African, Southern Western and lots of regional Western and Eu types , along with particular Italian types .