Increasing colostrum intake immediately after birth leads to better health, growth and higher long-term milk production
It has long been understood that quality colostrum intake just after birth is essential for the health of neonatal calves. The IgG that is transferred in the colostrum protects young calves from sickness and disease as they grow, and while they develop their own antibodies. It's essential that they attain at least 10 mg /mL of serum IgG from colostrum for transfer of passive immunity to be successful. But, what are the other benefits that colostrum can impart? And, how much colostrum is needed and how quickly after birth, in order to attain the greatest benefits? In their 2005 ground breaking study, Faber et al. addressed these questions and the results are quite striking.
In order to assess whether the amount of neonatal colostrum feeding impacted average daily gain (ADG) and long-term lactational performance, as well as the host of known health benefits, sixty-eight Swiss brown heifers were randomly assigned to receive either 2 litres (37 = 2L) or 4 litres (31 = 4L) of colostrum within one hour of their birth. Bottles were used to force-feed all calves, with the occasional esophageal tube being used if the bottle was refused. All calves were then managed in exactly the same way, after the initial difference in colostrum amount. For example, beginning a maximum 12 hours after the initial feeding, all calves were fed an additional cup of colostrum twice a day in addition to their regular milk feeding, for the first 14 days of life. After day 14, no colostrum was fed. All calves were weaned by eight weeks, at which time they were also all fed the same diet and otherwise treated similarly.
Differences in health and growth
As expected, calves who received 4 litres of colostrum within one hour of their birth had greater resistance to sickness and disease than those who received 2 litres of colostrum, with lower veterinarian bills. In fact, veterinary costs for calves in the 2L treatment were 70% higher than those in the 4L treatment. While the number of illnesses didn't vary between treatments, it was the nature of the illnesses of the 2L calves (requiring repeated treatments and monitoring) which caused the higher costs. Additionally, septicemia was common in the unhealthy 2L calves, signalling that they failed to absorb enough protective Ig.
Calves who received the 4L treatment were not only healthier, but also had higher ADG than the 2L calves up to 500 days of age, with 1.03 kg vs. 0.80 kg, respectively.
Differences in milk production
Perhaps the greatest benefit to the farmer between the two treatments can be seen in actual milk production through the first two lactations, as the 4L group produced significantly more milk compared with the 2L group. In fact, over the first two lactations, the 4L group produced 1027 kg more actual milk per heifer than the 2L cohort. While the exact action of the extra colostrum on the mammary glands is as of yet unknown, as Faber et al. state, "the growth-promoting constituents present in colostrum may be related to proliferation and maintenance of the mammary gland." While the researchers didn't test for actual concentration of IgG in the blood and based their findings solely on the feeding of 4 litres vs. 2 litres of colostrum, one thing is for sure: you can't argue with performance. And, if you want your heifers to have greater lactational performance, feeding 4 litres of colostrum within the first hour of life is a good way to get them on the right track.