Waste Milk from Antibiotic Treated Cows as Feed for Young Calves1,2

Abstract

Our objective was to determine whether discard milk from cows treated with antibiotics for mastitis and other disorders could be fed safely to young calves. In Trial 1, control calves were fed whole milk, the experimental group waste milk; calf starter plus hay were offered ad libitum. In Trials 2 and 3, fermented colostrum was fed to controls, and all groups were offered a dry complete feed. Trial 3 included one group fed waste milk to which .05% formaldehyde had been added prior to storage at ambient temperatures. Milks were fed to age 6wk in Trial 1 and 5wk in Trials 2 and 3. Total period of observation was from birth to age 8 wk. Growth by calves fed fresh waste milk was equal or superior to that by controls during both the milk feeding period and to 8 wk. Calves fed the formalin-preserved waste milk tended to reject it initially, resulting in lowered food intakes and slower growth to age 5 wk. These calves tended to suffer mild nutritional scours. Other health problems were minimal. Fermented colostrum contained greater numbers of microorganisms than waste milk; it also tended to show low inhibitory activity as indicated by the disc assay test for antibiotics.