Feeding Colostrum: Long-Term Gain

The recommended practice of feeding colostrum to newborn calves has more benefits than first believed. When your dairy calves achieve their potential, they reach maturity faster, calve at an earlier age and generally become more productive. Feeding colostrum has always been a key factor in getting young females off on the right track, but researchers have found it also puts more milk in your bulk tank when they join your milking herd.

Some recent studies have examined the impact of colostrum quantity and quality on the longer term success of dairy cows. Specifically, they have found calves receiving a higher quality and quantity of colostrum produce more milk in their first and subsequent lactations.

A University of Arizona study divided Brown Swiss calves into two groups. Just after birth, one group received four litres of colostrum and the other group two litres. These groups were then remixed and treated the same. Researchers monitored their subsequent first two lactations.

Calves receiving four litres at birth had a 30 per cent higher calf growth rate, had a 16 per cent higher survival rate to the end of second lactation and produced 2,263 litres more milk by the end of the second lactation. This result suggests getting high amounts of colostrum into calves early in life impacts positively on their productive lives as cows.

What are reasons for this result? Other studies completed by the University of Minnesota suggest healthier calves getting adequate colostrum can fight off disease better. Colostrum contains immunoglobulins, also known as antibodies. A calf's immune system uses these specialized proteins to identify and neutralize disease-causing pathogens such as bacteria and viruses.

For every incidence of respiratory infection, Minnesota researchers found, calving age increased by 0.21 months. Two or more incidences increased calving age by 0.53 months.

Heifers that had multiple disease outbreaks during their first 12 months had the lowest survival rate in the herd. Heifers that had no calfhood diseases were five per cent more likely to remain in the herd past first lactation than those with two disease incidences as calves. Calf health problems also affected milk production by one to five litres per day, this study found.

How does colostrum feeding help control disease and improve performance?
Calves with higher immunoglobulin status from colostrum feeding seem to be able to stop pathogens cold before they have to mount a full immune response. These animals don't have to divert energy and nutrients away from maintenance and growth to fight disease.

Calves with low immunoglobulin status need to mount a full immune response to fight a disease attack. That takes nutrients away from growth and maintenance

How much colostrum should you feed and when?
Calves will absorb around 35 per cent of immunoglobulins in colostrum if it is fed immediately after birth. This has been shown to decline to less than five per cent 20 hours after the calf is born. Some studies have shown calves fed colostrum from a bottle after birth had better passive immunity transfer than calves allowed to suckle their dams.

Feeding high-quality maternal colostrum at 12 to 15 per cent of a calf's birth weight will get it off to a solid start. General recommendations include four litres at birth and two to three litres more within the next eight hours.

How do you measure colostrum quality?
Generally mature cows have higher percentages of immunoglobulinsthey have lived longer, been exposed to more disease challenges and built up more immune system defenses. The immunoglobulin content in colostrum from a first milking is typically five to six per cent, or 50 to 60 grams per litre. It can range from less than two per cent (20 g per L) to greater than 15 per cent (150 g per L).

You can get an accurate estimate of immunoglobulins in colostrum by using an instrument called a colostrum hydrometer available from farm suppliers. Follow manufacturer directions and look for readings of more than 50 g per L.

Make sure the colostrum you feed to calves is from cows free of Johne's disease. As well, store colostrum carefully since bacteria can contaminate it quickly when it's left in a warm environment. It can be refrigerated for up to a week or frozen for up to a year.