Effect of calf stimulation during milking on milk yield and fat content of Bos indicus×Bos taurus cows

Suckling before milking is a common practice to stimulate milk let down in Bos taurus×Bos indicus cows in dual purpose herds, extensively used in tropical American lowlands. An experiment was carried out to evaluate the influence of four cow management strategies at milking on milk yield and composition and on calvesʹ live weight (LW) gain. Twenty-four Brahman×Holstein cows were used to compare four treatments: without calf stimulation at milking (W), suckling before milking until let down occurred (S), calf tied beside its mother during milking (P) and suckling before milking followed by calf tied beside its mother until the end of milking (SP). The cows were machine milked twice daily, at 06:30 and 15:30 h, and suckling was allowed for 30 min after morning milking until weaning at 17 weeks. On treatments W, S, P and SP, average saleable milk yields until weaning were 7.7, 9.7, 11.4 and 9.9 kg/day (P<0.05), consumed milk values after milking were 4.1, 2.1, 2.0 and 1.3 kg/day (P<0.001) and calvesʹ LW gains were 0.61, 0.46, 0.37 and 0.41 kg/day (P=0.056). It was shown that suckling before milking or the simple presence of calf during milking elevates the amount of saleable milk and its fat content, at the expense of consumed milk.