Feeding protected fish oil to dairy cows

This study evaluated the effects of feeding dual-protected fish oil, a source of omega-3 fatty acids, on milk production and reproductive performance in early- and mid-lactation Holstein cows. A total of 145 lactating cows (mean days in milk: 116 ± 72.5; average milk yield: 48 ± 10.8 kg/day) were allocated to two groups: a treatment group receiving 170 g/head/day of protected fish oil and a control group receiving 132g/head/day of palm fatty acids. The dual-protection process involved Ca-saponification and coating with palm fatty acids. The supplements were top-dressed daily for 110 days. Compared with the control group, cows fed protected fish oil showed higher milk yield and a trend toward improved fat-corrected milk yield, with no significant changes in milk fat or protein percentages. Reproductive parameters improved in the treatment group, with a shorter interval from calving to first oestrus and a lower insemination-to-pregnancy ratio. In conclusion, dual-protected fish oil supplementation may enhance both reproductive and productive outcomes in lactating dairy cows.