Mastitis prevalence in first calf beef heifers and effect on calf weaning weight

摘要

A study was conducted to determine the prevalence of mastitis in pregnant beef heifers and the effect of this disease in dams on calf weaning weight of their calves during the subsequent lactation. Bacteriological analyses of quarter milk samples collected prepartum and during lactation showed that CNS predominated, with SCC of 436,000/mL followed by S. Aureus, with SCC of 6,000,000/mL. Dams with CNS mastitis weaned calves that weighed 15 lb lighter than uninfected controls, and dams with S. Aureusmastitis weaned calves that weighed 23 lb lighter. At a market price of 0.85 dollar per lb for 400- to 500-lb beef calves, producers may be losing over 18.00 dollar per head or 5 percent of sales value due to this disease.