Calf milk pasteurization
In the ongoing quest for improved biosecurity and maximum dairy herd health, it stands to reason that pasteurizing calf milk would be a worthwhile and beneficial management practice. Yet in reality, conservative industry estimates indicate that far fewer than half of all dairies currently perform any type of heat treatment on waste milk fed to calves. Is calf milk pasteurization effective? Does it address current disease and biosecurity concerns on the average dairy? And if so, what role can dairy practitioners play in promoting its adoption?
Heat inactivation of Mycobacterium paratuberculosis in raw milk: are current pasteurization conditions effective?
Currently, it is not known whether commercial pasteurization effectively kills Mycobacterium paratuberculosis in contaminated raw milk. Results from holder test tube experiments indicated that a residual population of viable bacteria remained after treatment at 65, 72, 74, or 76 degrees C for 0 to 30 min. Use of a laboratory-scale pasteurizer unit demonstrated that treatment of raw milk at 72 degrees C for 15 s effectively killed all M. paratuberculosis.
Waste Milk from Antibiotic Treated Cows as Feed for Young Calves
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 6 wk in Trial 1 and 5 wk 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.