Abstract

Herbage dry matter content and water-soluble carbohydrate influence cow intake and production. Delaying the time of grazing may increase the dry matter and water-soluble carbohydrates content of herbage and increase grass consumption and milk production. This study determines the cow response to early (8:00 h) and late (11:30 h) offer of winter pasture (Lolium multiflorum) for primiparous cows 120 days in lactation. Herbage dry matter content, grazing time and daily herbage dry matter intake increased when the time of grazing of the winter pasture was delayed (140 vs 171 g/kg dry matter (DM), 71 vs 110 minutes and 2.7 vs 4.8 kg DM/cow/d respectively; P <0.05) while the increment in the water-soluble carbohydrates content of the herbage was not significantly different between treatments (53 vs 75 g/kg DM; P = 0.09). As a consequence of the higher daily herbage dry matter intake of cows grazing winter pasture late in the morning, daily milk and milksolids production was higher than pasture offered early in the morning (29.2 vs 31.0 L/cow and 2.05 vs 2.19 kg/cow respectively; P <0.05).

GA, Acosta, JL Rossi, A Ayala Torales, and A Acosta

Proceedings of the New Zealand Society of Animal Production, Volume 69, Christchurch, 46-50, 2009