Growth and reproductive development of Angus, Brahman, Bonsmara, Romosinuano, Tuli, and Wagyu bulls

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to digital@library.tamu.edu, referencing the URI of the item.Includes bibliographical references (leaves 100-112).Issued also on microfiche from Lange Micrographics.The purpose of these experiments was to evaluate growth and reproductive development of: fall (F; n=7) versus spring (S; n=10) born Brahman bulls (Experiment I), and Angus (n=7) and Brahman bulls (n=10) in comparison to Bonsmara (n=8), Romosinuano (n=10), Tuli (n=10), and Wagyu (n=10; Experiment II). Treatment regimens were similar between the two trials. Bulls were maintained together and fed a 3:1 (corn:soybean meal) supplement containing lasalocid. The supplement was fed at 1.5% of BW and bulls had free access to coastal bermudagrass hay, water, and a salt/mineral mix. Measurements were taken at 14-d intervals until bulls reached sexual maturity (SM; ejaculate with [>] 500x10⁶ sperm with [>] 50% motility). Measurements included BW, body condition score (BCS), hip height (HH), scrotal circumference (SC), and testis length. Upon attaining a 21 cm SC, ejaculates were collected and continued through SM. Stages of reproductive development were first sperm, puberty (50x10⁶ sperm/ejaculate; P), and SM. No differences (P>0.10) were found in Experiment I for BW, BCS, SC, or paired testis volume (PTV) between seasons of birth at FS or P. Age at FS tended (P0.10) scrotal circumference throughout the trial while Wagyu bulls had the smallest scrotal circumference at each stage, with Romosinuano and Tuli falling intermediate. Newly introduced breeds developed competitively to Angus and more rapidly than Brahman bulls