Many variables affect a calf’s health and performance. However, calf expert Dr. Sheila McGuirk, DVM, University of Wisconsin-Madison School of Veterinary Medicine, said three main categories can really guide how calf raisers provide top notch care to their calves.
During her presentation at the Dairy Calf and Heifer Conference, McGuirk told producers to think of a calf like a three-legged stool, with its health balanced on colostrum, environment and nutrition. The stronger each of these areas is, the better off a calf will be.
Every calf raiser probably knows that colostrum is vital to a calf’s survival in the first couple of months because it boosts the immune system. But McGuirk said colostrum’s role goes far beyond that.
“Colostrum also has long-term implications on growth rate, feed efficiency, reproductive efficiency, milk production and longevity in the herd,” she said.
McGuirk reminded attendees that colostrum quality varies from one cow to the next and is influenced by immune status, parity of the cow, genetics, hormones and many other factors. She said that it can be helpful to select colostrum donors by health and vaccination status, but cowside tools that accurately measure immunoglobulin (IgG) levels are essential. Colostrum should have a minimum IgG concentration of 50 gm/L.
In addition, producers should take steps to minimize colostrum contamination and work to get the colostrum to the calf as quickly as possible. If producers are challenged with getting enough high quality colostum to the calves fast enough, they should consider using colostrum replacers.
Industry standards say that a calf should double in birth weight by 56 days of age. To meet that goal, calves should be fed 1.8 to 2.5 pounds of milk solids per day and have unlimited access to high quality calf starter and water. McGuirk cautioned producers to make gradual adjustments to the diet when increasing milk volume.
“Variability in the milk diet of calves puts them at risk for indigestion, bloat, ulcers, abnormal abomasal emptying, intestinal motility problems, altered intestinal flora, and rumenal, abomasal and intestinal bloat,” she said.
McGuirk also said that water is always an essential nutrient, but is especially important when calves are outside their critical temperature range, fed a diet high in milk solids or scouring. When it’s cold, calves should be fed water immediately after milk. That’s because they’re more likely to drink while they’re still standing. If you wait, the calf is much less likely to leave its warm bedding to drink water later.
When it comes to the calf’s environment, cleanliness reigns supreme. Remove the calf from the calving pen within 10 minutes after it’s born to protect it from pathogens in the maternity area. Make sure it is draft-free and has adequate bedding in a pen that has been sanitized between calves.
McGuirk said approximately 30 square feet of space is recommended for calves in individual pens and empty space is also important.
She said, “There should be 15 percent more pens than calves at maximum occupancy to provide time to clean, disinfect and rest pens between successive calf occupants.”
As the calf grows, you should still take the proper steps to limit its exposure to pathogens. This includes removal of refused milk, milk replacer, water and starter. The bedding should also be dry. Remember that most bacteria lie at the bottom of the calf pen. By providing deep bedding, you increase the distance between the calf and pathogens.
Just like it is with colostrum and nutrition, consistency is also important in terms of the calf’s environment. Limit the number of times you move a calf and allow enough time for gradual changes and adjustments in location, occupants, feed and bedding management.
Lastly, McGuirk reminded producers that “a best environment” doesn’t exist. Any system can work and any system has its challenges. As with anything, the key to optimizing the calf’s environment is good management.