Do intensive calf nutrition programs make calves grow faster? Do they produce heifers that produce more milk as adults? And, ultimately, do they make economic sense?
At the recent 4-State Dairy Nutrition and Management Conference in Dubuque, Iowa, Michigan State University researcher Mike VandeHaar shared his observations about intensive calf feeding programs. He reviewed research conducted with his Michigan State colleague Miriam Weber Nielsen, and provided their conclusions about intensive feeding programs.
In the Michigan State study, 40 calves were raised on a conventional, 20:20 milk replacer at 1.2 percent of bodyweight; and 40 calves were fed an intensified, 28:15 milk replacer at 2.1 percent of bodyweight. The traditionally raised calves were restricted on starter grain intake to limit gains to 1.0 pound per day, while the calves in the more nutrient-dense program were allowed starter grain free-choice. Both groups of calves were weaned gradually in the last week, and were removed from their milk diets completely at 42 days of age.
Calves were managed similarly after weaning and bred by size. The trial results included:
· Intensively fed calves entered lactation at an earlier age (701 vs. 715 days).
· After adjusting milk yield for genetics using parent-average milk, first-lactation-projected 305-day ME milk yield was 4 percent higher for intensively fed calves.
The researchers noted that allowing the traditional group free-choice access to starter grain likely would have improved their growth rate, with unknown influence on their future milk production.
Based on this research and that of others who have examined intensive feeding for several years, VandeHaar offered several overall conclusions:
(1) Intensive milk-feeding programs can produce larger calves at weaning and heifers that reach breeding size at a younger age.
(2) Intensively fed calves may have looser stools during the pre-weaning period, but health status does not appear to be affected.
(3) Milk yield tends to be higher in calves raised on intensive feeding programs. The economic advantage of this improvement is dependent on milk prices.
(4) Feed costs for intensive rearing will be about $10 more per week, but this likely is recovered by a decrease in age at first calving and a trend toward higher milk production. If milk production is not increased, the cost of intensive milk feeding is hard to justify. If milk production is increased, it is worth it.
(5) Calves in cold weather need more milk in conventional systems; intensive calves could probably have a milk replacer with more fat.
(6) Intensive feeding requires a higher degree of management.
(7) The exact level of nutrients necessary to improve gains and growth without overfeeding have not been determined yet. VandeHaar questions whether the protein:fat content and feeding level of current, intensive programs is optimal. He would like to explore if similar improvements could be achieved with somewhat lower milk-fed nutrient levels, and/or if methods to enhance starter grain intake could be a workable alternative to promoting growth in young calves.
Read the full text of VandeHaar's paper here: