Recent trends occurring in broiler primary breeding companies are described. The structure and operation of broiler primary breeder companies are described from pedigree elite populations, through great-grandparent and grandparent generations, down to the parent stock. The relatively low value of fertility and hatchability, compared with yield and feed efficiency as selection traits, is assesse...

A study was undertaken to test the effect of 2 commercially available probiotics on the production efficiency of broiler chickens hatched from the same breeder flock at 3 different ages (28, 43, and 57 wk). At each of the 3 breeder flock ages, 1,600 broiler chickens were hatched and randomly allocated to 1 of 4 treatments: 1) no probiotics (control), 2) probiotic 1 administered in the drinking ...

Penelitian tentang repeat breeder pada sapi Simpo di KPT Maju Sejahtera Kecamatan Tanjung Sari Kabupaten Lampung Selatan dilaksanakan Februari 2022 dengan 4 inseminator, 5 peternak, dan sampel 190 ekor yang telah inseminasi Buatan. ini bertujuan untuk mengetahui besarnya faktor-faktor mempengaruhi KPT. Sejahtera, Sari, Selatan. Metode digunakan yaitu metode survey data diperoleh cara sensus. Se...

In size-structured groups, conflict over rank, resources or access to breeding opportunities is expected to be greatest among individuals that are similar in size. We tested this general prediction using the cooperatively breeding African cichlid, Neolamprologus pulcher. We predicted that, when size differences between group members were small, we would observe some or all of: increased aggress...

In order to investigate the potential influence of stress as a component of the repeat breeding syndrome, the adrenocortical capacity for steroid production was evaluated in ovariectomised dairy heifers. In repeat breeder heifers (RBH), marginally elevated plasma progesterone levels during oestrus, so-called suprabasal progesterone levels, have earlier been measured and are believed to impair f...