Administration means to alter chicken heifer reproductive achievements
Just the right options and you may development of substitute for heifers raises the chances one heifers typing innovation programs usually interracial cupid reddit conceive at the beginning of new reproduction seasons followed by improved stayability . Administration steps geared towards growing earliest breeding year reproductive achievements is actually talked about below, and lots of are directed for the enhancing the percentage of heifers reaching adolescence until the start of the breeding season. Particularly methods include the gang of older and you will heavy heifers during the weaning , nutritional handling of heifers to arrive a defined portion of their mature bodyweight from the beginning of the breeding seasons [16, 22], reproductive system scoring so you’re able to display screen heifers getting adolescence
30 d until the start of breeding season , brand new implementation of good progestin-situated estrous synchronization process [18, 32], and the incorporation regarding questioned progeny differences (EPDs) to select heifers with more hereditary merit getting fertility.
Chronilogical age of heifers
The selection of replacement heifers which might be born early in the latest calving 12 months is a vital step to optimizing total reproductive success. It’s requested one to early created heifers commonly go into the reproduction season with more morphological and mental readiness than their young herd mates.
Inside the a survey by the Funston and you may colleagues, heifers born in the first 21 d of the calving season was indeed big at the pre-reproduction than just heifers produced on second otherwise 3rd age the new calving season (296, 292 and you can 276 kilogram, correspondingly, ). Likewise, 70% off early produced heifers was in fact cycling by beginning of the its first breeding seasons, compared to 58% and 29% away from heifers born on the next and you can third 21-d period, correspondingly. For that reason, more mature heifers exhibited deeper maternity rates (90%) compared to 86 and you may 78% to have heifers that have been produced for the consecutive 21-d windows of your own calving period, respectively . (tovább…)