Many issues can impact an animal’s ability to show heat. If you feel you are not finding cows in heat, it might be time to take a closer look at the issue.
First, you need to determine if the problem exists throughout the entire herd or within a specific subgroup. To do this, analyze your dairy's computer record system. Look at records for reproduction and events that have happened by lactation or lactation group. Once the group in which the problem exists is determined, you will be better able to find possible causes and solutions.
Here are some potential causes to consider:
How does flooring affect cows showing heat?
Slippery floors can be a deterrent to cows exhibiting heat and can also cause injury to animals. Generally concrete is the most common flooring surface in dairy facilities. To make concrete flooring more cow-friendly, one could groove or scabble slippery floors. Caution must be used when using grooving or scabbling floor options, as not to make the surfaces too abrasive on hooves. Another option is to use grooved rubber belting or similar rubber products.
How does lameness affect cows showing heat?
Lameness causes stress on an animal. Lameness also tends to cause animals to lie down and eat less. Obviously, if an animal lies down more, it becomes more difficult to observe signs of heat. And, if an animal eats less, lameness can cause a cow to lose body condition.
How does body condition loss affect cows showing heat?
A one-point loss in body condition can inhibit an animal's ability to exhibit heat. Keeping the ration adequate to prevent body condition loss is critical. Remember a cow is a mother; she needs enough energy to produce milk (feed her calf) before she will want to reproduce again.
How does the ratio of open to pregnant cows affect cows showing heat?
The higher the number of pregnant cows in a pen the lower the amount of estrus that is shown; pregnant cows and cows in mid-cycle are much less likely to mount cows in or near heat. A possible solution for this issue is to maintain a higher percentage of open cows within the breeding group.
How does transitioning affect cows showing heat?
The more metabolic problems an animal has when freshening, the greater probability of anestrus. According to research, clinical ketosis, dystocia and retained placentas are associated with more days to first service and a lower conception rate at first service. Overcrowding of transition groups may also lead to more metabolic problems at or after calving.
How does failure of proper observation for estrus affect cows in heat?
Some estimates place undetected heats on farms in the USA at 50%. One solution for the issue of failure to properly observe estrus may be to adequately train employees in heat detection technique. In regard to specific timeframes for observing animals for heats, the proper time to observe animals is not while they are eating; instead, for best results, it should be every employee's job to make sure they observe animals at all times and properly identify the animals in heat. If herds are housed in stanchion barns, they need to be turned out daily, to conduct proper heat detection.
How does heat stress affect cows in heat?
It is harder to detect heats during times of extreme high temperatures, and if you are able to catch them in heat, many have a hard time staying pregnant. A solution is to engage in heat abatement strategies, which may include sprinklers, fans, tunnel-ventilated barns, or multiple water sources for cows on pasture.
In conclusion, there are many different factors that could cause you to say, "My cows are not showing heat and conceiving the way they should." To overcome the obstacles, drill down through all layers to find the source of the problem - problems that could relate to the cows not showing heat or people not heat detecting correctly. Several products are also available to aid in heat detection such as Reveal™ Livestock Markers, Allflex® Livestock Intelligence cow monitoring systems, heat detection training and more. Work with your local resources (veterinarian, GENEX representative, etc.) to determine your challenges and the right fix for your operation.
Fourichon, C., H. Seegers, and X. Malher. “Effects of Disease on Reproduction in Dairy Cows.”
Theriogenology 53.9 (2002). 1729-59.Stevenson, Jeffrey S. “The question would be are their cows really not showing heat or are we not heat detecting correctly.” 1997.
Varner, M. A. “Stress and Reproduction.” Dairy Integrated Reproductive Management.