By Lisa Schnirring
Scientists who examined the impact of an H5N1 avian flu outbreak in an Ohio dairy herd that had about 3,900 cows found a milk production drop in clinically affected cows that lasted 60 days and extensive asymptomatic infections in other cows. The team, led by researchers at Cornell University, published their findings as a preprint study in Nature Portfolio.
The first illness in the herd was noted about 2 weeks after apparently healthy lactating cows from Texas were introduced into the herd. Decreased rumination and a decline in milk production appeared to decline about 5 days before clinical diagnosis.