[Birth-rate and productivity in Assaf and Assaf x Blackbelly sheeps sincronized and inseminated with fresh and frozen semen] | Natalidad y prolificidad en ovejas Assaf y Assaf x Blackbelly sincronizadas e inseminadas con semen fresco y congelado

artificial insemination brebis breeds (animals) evaluation ewes intervalle entre parturition intervalo entre partos oestrus synchronization oveja parto parturition parturition interval performance de reproduction peru progesterona progesterone race (animal) razas (animales) reproductive performance reproductividad semen sperme synchronisation de l'oestrus