Silymarin and lycopene administration in periparturient dairy cows: effects on milk production and oxidative status

AIMS: To establish during late gestation and early lactation the effects of supplementing silymarin, a natural hepatoprotective substance, combined with a powerful antioxidant, lycopene, on milk production and on serum biomarkers of oxidative status. METHODS: Italian Friesian dairy cows were given individually a supplement containing a mixture of silymarin (7.77 g/day/cow) and lycopene (1.27 g/day/cow) (n= 10) or no supplement (control; n= 10). Treatment was administered from 7 days before the expected calving date to the first 14 days in milk. At 7 days before the expected calving date, at calving, and 7 days postpartum, body condition score (BCS) and concentrations in serum of reactive oxygen metabolites (ROM), total antioxidant capacity (OXY) and thiobarbituric acid reactive substances (TBARS) were evaluated. Bodyweight, milk production, and somatic cell count (SCC) were determined at 7, 14 and 21 days postpartum. RESULTS: The mean time of treatment prior to calving was 6.3 (min 4, max 11) days. Compared with control cows, treatment increased energy corrected milk yield (33.3 vs. 37.8 (SEM 1.10) kg/day; p= 0.006) and milk fat yield (1.14 vs. 1.32 (SEM 0.06) kg/day; p= 0.05) over the first 21 days of lactation. Treated cows had lower mean log(10) SCC compared to control cows (4.9 vs. 5.24 (SEM 0.11) log(10) cells/mL) and had lower overall concentration of TBARS (1.47 vs. 1.59 (SEM 0.016) nM/mL; p< 0.001), but similar concentrations of ROM and OXY in serum. However there was a treatment by time interaction (p= 0.09) for OXY, and at calving mean OXY was higher in treated cows compared with pre-calving values (p< 0.001). CONCLUSIONS: Despite the acknowledged limitation of the study, i. e. the small number of animals, our results suggest that silymarin and lycopene, as health-beneficial feed supplements, may help dairy cows in metabolic adaptation during the first stages of lactation.