Effects of herd origin - AI stud and sire identification on genetic evaluation of Holstein Friesian bulls [artificial insemination]

animal breeding artificial insemination attitudine alla riproduzione breeding value bulls descendance fecondazione artificiale grasa de la leche grasso del latte italia italie italy mejoramiento animal metodi statistici milk fat milk protein milk yield performance de reproduction progenie progeny proteine del latte rendement laitier rendimiento lechero reproductive performance reproductividad sire evaluation statistical methods taureau tori toro valore genetico valutazione del riproduttore