Study ties fetal sex to milk production
A new study offers the first evidence that fetal sex can affect the amount of milk cows produce, a finding that could have major economic implications for dairy farmers. The study, co-authored by a Harvard scientist, examined 2.4 million lactations by nearly 1.5 million dairy cows in the United States, finding that cows that gestated back-to-back daughters produced as much as 1,000 pounds more milk than those that give birth to sons over the first two lactations. The work is described in a Feb. 3 paper in PLoS One. The study authors included an estimate on the potential value of using artificial insemination techniques to increase the number of female calves cows produce. “If this were adopted by the dairy industry today, not counting the cost of the technology for sperm selection, the growth in terms of wholesale milk value is in the ballpark of $200 million gross — just by manipulating the...