Balance milk and starter feeding for efficient calf growth

By Dr. Zach Sawall
A calf is born with a sterile rumen environment void of bacteria, protozoa and fungi.  Microbes in the gut populate slowly at first, but speed up over time.  This process of developing the calf into a ruminant is one of the main goals of the nursery phase.  This is necessary for a successful transition into weaned groups to maintain growth and reduce disease incidences.

Colostrum acts as a natural prebiotic, promotes the growth of beneficial bacteria, and reduces the colonization of E. coli and other pathogenic bacteria in the small intestine.  The establishment of beneficial bacteria from colostrum happens within the first 12 hours after feeding.

After colostrum feeding, calves need to transition onto the milk feeding program.  The amount of liquid fed will influence the amount of starter great intake.

If a calf consumes more than 0.4 pounds of fat from milk, starter grain intake begins to be suppressed.  Therefore, to maximize starter grain intake, a balanced milk feeding program should accompany a quality starter grain.

Starter grain matters
In addition to the liquid feeding program, calves gain energy by acquiring glucose through volatile fatty acid (VFA) production from starter grain digestion in the rumen.  For this to happen, the rumen must develop and mature, which does not occur overnight.  But, the sooner it happens, the better.

Research shows that calves that consume starter grain at a younger age have a more developed gastrointestinal (GI) tract and a superior ability to fight disease.  With a stronger immune system, the improved digestion and fermentation of nutrients in the rumen can provide energy and protein for additional growth.  Microbial protein produced through starter grain digestion and fermentation also has nearly optimum amino acid composition for growth and development.

Fueling starter intake
A few management factors can promote starter grain intake.

• Young calves must be able to easily reach the grain.  Ensure starter buckets are no higher than 24 inches from the top of the bucket to the ground.
• Offer fresh starter grain to young calves daily to encourage starter intake.  The starter grain should have a limited amount of fines.
• Water is a vital nutrient to achieve proper intakes of high-quality starter grain.  Calves will need to consume approximately 4 pounds of water (0.5 gallons) for every 1 pound of starter grain consumed.

Know where you’re at
Take time to monitor starter grain intake as calves go through the nursery phase.  At the time of weaning, calves should consume 4 to 6 pounds of starter grain per day.

In addition to grain intakes, pay attention to manure color and consistency.  As the rumen matures, manure changes color from a light brown to a darker brown.  The manure consistency will also thicken as the GI tract develops.

The sooner that calves consumer starter grain, the greater the development of papillae growth and density in the GI tract, which will ensure that calves are well on their way to becoming mature, productive ruminants.

This article was originally written for the September 25 issue of Hoard’s Dairyman.

About the author:  Dr. Zachary Sawall grew up on a dairy farm in northeast Wisconsin. He attended the University of Minnesota where he earned his bachelor’s degree in animal science with an emphasis in ruminant nutrition. In 2013, Sawall was named Outstanding Master’s Student by the Department of Animal Science at the University of Minnesota.  He continued there to earn his Ph.D. in ruminant nutrition.  Sawall joined Vita Plus in 2015 as a dairy nutritionist and technical services specialist in central Wisconsin. In his free time, Sawall enjoys hiking, hunting, spending time with his wife, Sandra, and their family, and working on their parents’ dairy farms.