Submitted to: International Virtual Conference on Infectious Diseases of Animals
Publication Type: Abstract Only
Publication Acceptance Date: April 18, 1997
Publication Date: N/A
Technical Abstract: Concentrations of retinol (Vit A), beta-carotene (BC), alpha-tocopherol (Vit E) and all-trans-, 13-cis-, and 9,13-di-cis-retinoic acids (RA) were determined in plasma taken weekly from calves from birth to 7 wk postpartum. Calves fed 1-2 L of pooled colostrum within 12h of birth were subsequently divided into groups fed milk replacer without retinyl acetate (Vit A) or BC (n=5), milk replacer with vitamin A (n=5), or milk replacer with BC (n=6). Vitamin and RA determinations were made by reverse-phase HPLC. Plasma concentrations of all metabolites were lower (P<.05) at birth, and increased from 1 to 7 wk postpartum. Plasma BC concentrations were at least 10 times greater in BC-supplemented calves than in control and Vit A-supplemented calves from 1 to 7 wk. Concentrations of BC in control and Vit A-supplemented calves were not significantly (P>.05) different from 1 to 7 wk postpartum. Vit A-supplemented calves had higher (P<.05) plasma retinol concentrations than control calves at 4, 6, and 7 wk. Plasma Vit A concentrations from control and BC-supplemented calves were not different (P>.05), suggesting that high dietary levels of BC do not affect Vit A concentrations.