Research done by the USDA has shown that moving calving time from the spring to late winter increases calf growth. This means that calving season will be in early March instead of early May, which puts calves reaching 180 days of age in early September, while the grass is still growing, compared to early November, when the growing season slacks off. Calves that are born in late winter are shown to average 13 percent heavier than those born in spring.
Benefits of Early Calving Are Increasing Due to Late Winter Warming