In the November issue of Dairy Herd Management, veterinarian Mel Wenger summarized three important monitors for maximizing return on investment from your heifer program.
The first area discussed was age at first calving (AFC).
Obviously, we want to get the replacement heifer into the milking herd as soon as possible so we can begin to reap the profits of milk production. However, it is important to keep this monitor in perspective and realize what areas of your operation impact the age when a heifer freshens. If we use this metric as a benchmark, we have already missed the boat, as it will take a long time to change this parameter given the lag (gestation length).
So where do we start?
First hours of life
Well, some may say it all starts with age at first breeding, but I’ll suggest that we go back to the first few hours of life. We know that colostrum is important, but many people do not link it to their AFC. A number of peer-reviewed trials have demonstrated the benefits of passive transfer (the transfer of antibodies from colostrum to the calf) on improved growth rates, reduced treatment and mortality rates, decreased age at first calving and increased first- and second-lactation milk production. So, this is where it starts. What we do during the first hours of life can impact the AFC.
Are you routinely monitoring colostrum quality and serum total protein in calves?
Maximize growth potential
Secondly, we must maximize the growth potential of the milk-fed calf so that we can reach the desired height and weight at the optimal age.
Once a calf is weaned, we can’t forget about her either. I see herds where growth during the milk feeding phase is excellent and then the program breaks down. We need to continue to balance and feed rations that are suitable for the specific weight of the heifer. Feeding one ration through the transition and growth phases will not provide for optimal growth potential. It is important to continue monitoring growth on a regular basis so that management and ration adjustments can be made.
Are you routinely monitoring heifer rations?
Get them pregnant
Once we have that heifer to the optimal height and weight for breeding, we now need to get her pregnant. It is common to find herds with excellent attention to the adult herd reproduction program, but for some reason it does not transfer over to the heifer program.
There are a number of synchronization programs for heifers that can yield excellent results with proper compliance. But starting with a routine program for heat detection should be a top priority. Then, work with your veterinarian to develop an overall program, just as in your cow herd, to get those heifers not seen in heat inseminated. Routine determination of open or pregnant status and re-insemination is obviously another critical step of the program. A wide breeding window will just yield a wide window for AFC.
Do you have a routine heifer reproduction/synchronization program?
Once you get these heifers pregnant, don’t forget them again. Properly balanced rations, vaccination protocols and pre-fresh transition programs will all benefit the soon-to-be-fresh heifer that enters your milking herd.
In this health column last month, Mel Wenger provided an excellent review of heifer nutrition and transition pen management. Pick up that issue again.
In summary, don’t forget that age at first calving is a number with a lot of lag time. We can start doing a great job growing and breeding heifers today, but our AFC won’t change for a long time. Select monitors that are timely and relevant to access your program. It starts within the first hours of life and gets back to the basics. Excellent colostrum and health management, optimal milk-fed and transition/pre-breeding growth, attention to reproduction and pre-calving management are the key areas to develop protocols and monitors to get that heifer putting milk in the tank.
Mark J. Thomas is a veterinarian and partner in Countryside Veterinary Clinic, LLP and Dairy Health & Management Services, LLC in Lowville, N.Y.