The productive system could be generally classified as
semi-intensive pasture grazing. Stocking rate of the grazing
area was approximately 5.5 cows/ha. Pasture was
composed of perennial Bermuda grass Tifton 85 (Cynodon
spp) during late spring and summer (warm season) and
Raygras/Trifolium spp during fall and winter (cold season).
Lactating cows were maintained exclusively on pasture,
receiving corn silage and concentrate after each milking to
provide nutrition requirements; nutrient requirements of
dairy cattle [10]. Concentrate was made of soybean meal
(44%–48% crude protein), citrus pulp, rice bran, milled
sorghum grain, wheat bran, and a mineral–vitamin premix,
containing approximately 20.0% to 22.0% crude protein,
3.5% ether extract, 85.0% dry matter, and approximately
70% total digestible nutrients. The amount of concentrate
offered changed according to milk production and stage of
lactation. An anionic prepartum supplementation was
provided for at least 21 days and a maximum of 30 days,
based on the nutrient requirements of dairy cattle (2001)
recommendations and urine pH monitored (pH 6.0–6.5
indicating anionic supplementation effectiveness).