Effects of the irrigation and of the integration between setaria-grass and ryegrass pastures on milk production

Abstract

The experiment was carried out at the Embrapa-Centro Nacional de Pesquisa de Gado de Leite, in Coronel Pacheco, MG, Brazil, during two periods of dry season. The objective was to evaluate the milk production from crossbred Holstein-Zebu cows kept exclusively under setaria-grass (Setaria sphacelata (Schum.) Moss., cv. Kazungula) and ryegrass (Lolium multiflorum Lam.) grazing conditions. Treatments were: (T₁) = cows grazing on irrigated setaria, plus two to three hours grazing ryegrass; (T₂) = cows grazing on setaria without irrigation, plus two to three hours grazing ryegrass; and (T₃) = cows grazing on irrigated setaria. Six 2^nd to 4^th lactation cows were used for each treatment, in each period. Dry matter availability (DMA) was kept around to 1,800 and 1,500 kg/ha, for setaria-grass and ryegrass, respectively. Extras cows were used to keep DMA as proposed. Fat corrected, milk produced per animal and per area and the stocking rates observed were: 12.2, 10.8, and 8.7 kg/cow/day; 28.1, 24.4, and 21.7 kg/ha/day; and, 2.3, 2.3 and 2.5 cows/ha, respectively for treatments T₁, T₂ and T₃.