Milk production by dairy cows grazing 2 red clover cultivars with and without sodium supplementation

Abstract

Pure swards of ‘Grasslands Pawera’ and ‘Hamua’ red clovers and a mixed ryegrass-white clover sward were laxly grazed by dairy cows in spring, summer, and autumn. In spring and autumn, half the cows were dosed daily with 30 g of sodium chloride. Milk production was similar from all swards in the spring. Cows grazing mixed pasture produced less (,P<0.05) milk, milk fat, and milk protein in autumn than those grazing Hamua or Pawera, and less (P<0.05) in summer than those grazing Hamua. Cows grazing Hamua produced more (P<0.05) milk protein in summer and autumn than those grazing Pawera. Sodium supplementation had no significant effect (P>0.05) on milk production from any of the swards.

Keywords:

• red clover
• Pawera
• Hamua
• Trifolium pratense L.
• milk production
• sodium supplementation
• dairy cows
• nutrition