New Delhi, January 01, 2018: Variation in nutrient content and bacterial counts in pasteurized milk fed to dairy calves might be more than expected, according to research findings by Land O’Lakes Animal Milk Products Company.
“Many farms have a readily available supply of waste milk and want to feed it to their calves,” said Tom Earleywine, director of nutritional services at Land O’Lakes Animal Milk Products. “But even if you pasteurize waste milk, it isn’t providing consistent nutrition for calves.”
Solids levels as well as protein and fat percentages in pasteurized milk can change day to day — and even from feeding to feeding. That high level of variation makes it challenging to provide a consistent nutritious diet to young calves, Earleywine said.
Variations in total solids, fat and protein percentages occur when milk is mixed from cows in different lactation stages and health statuses. That can cause gaps in nutrition. Research conducted by Land O’Lakes scientists showed total solids in pasteurized-waste milk can vary as much as 6.58 percent on individual farms, with protein variation of 7.9 percent and fat variation of 17.3 percent agupdate.com.
Concern about antibiotics in waste milk has given some dairy producers pause when deciding whether to feed pasteurized waste milk. Of samples in the study, about 57 percent contained traces of antibiotics. Many factors may affect antibiotic resistance in calves. But research shows an increase in resistance in calves fed waste milk, compared to calves fed milk replacer.
“You can’t always rely on an on-farm pasteurizer to effectively kill 100 percent of bacteria,” Earleywine said.
More than 40 percent of pasteurizers in the Land O’Lakes study failed to kill a necessary amount of bacteria when tested immediately after pasteurizing. Samples tested at the last calf fed showed there was more bacteria present at the end of the feeding.
“Exposing calves to milk with a high pathogen load can increase incidences of sickness, leading to lower performance and even mortality,” Earleywine said. “Proper management of milk, pasteurizers and feeding equipment — along with supplementing a pasteurized milk balancer and feeding milk replacer to younger calves — can help reduce bacteria fed to calves and improve nutritional quality of their diet.”
The study was conducted from October 2006 to January 2017. Pre- and post-pasteurized milk samples were collected from 618 dairies throughout the United States, with each farm feeding between five and 5,000 calves. Milk samples from each farm were collected for seven consecutive days to determine total solids, protein, butterfat, somatic cell count, antibiotic presence and bacteria count.