Supplementing lycopene combined with corn improves circulating IgG concentration in pregnant ewes and their lambs

Lycopene (C₄₀H₅₆, a non-provitamin A carotenoid) is a lipid-soluble pigment and a natural antioxidant with immunomodulatory activities. The objective of this study was to investigate the effects of lycopene with or without corn supplementation on circulating hormones, white blood cells, immunoglobulin G (IgG) concentrations, quality of colostrum in pregnant ewes, and IgG concentrations in newborn lambs. Forty multiparous single-bearing ewes (68 ± 8.4 kg body weight, mean ± SD) were fed in four groups of CONTROL (fed a basal diet (BD)), CORN (BD + 300 g/day corn), LYCOP(BD + 100 mg/day lycopene), and LYCORN (BD + 300 g/day corn + 100 mg/day lycopene). The quantity and chemical composition of colostrum were determined. Blood samples were taken from ewes right after lambing and from lambs at 3 and 24 h of age. Results showed that corn supplementation increased (P < 0.05) udder volume, the quantity of colostrum, as well as percentage of lactose, and protein in colostrum. Corn-supplemented ewes had higher circulating glucose, prolactin, and estradiol but lower urea and progesterone than control ewes. The ratio of progesterone to estradiol (P₄/E₂) in the blood of pregnant ewes decreased (P < 0.05) after corn supplementation. Lycopene, irrespective of corn, increased the percentage of lymphocyte cells in pregnant ewes. Both corn and lycopene increased circulating IgG concentrations and subsequently increased the total IgG in colostrum at 6 h post-partum. Lycopene significantly elevated the circulating IgG at 24 h of age in lambs. In conclusion, lycopene along with corn supplementation additively increased concentrations of IgG in the blood of ewes and in the colostrum, which resulted in an enhancement of passive immune transfer to the newborn lambs.