A shorter calving season can have many benefits
There are a number of beneficial reasons for a producer to work toward shortening their calving intervals. A smaller window for laborious tasks like round-the-clock calf checks, a calf crop that will be ready for market at about the same time and being able to identify the most productive cows in the herd, to name a few. While this might seem like a daunting task, shortening the calving interval can be broken into achievable steps.
Keep Up Condition
It is no secret that well-conditioned females breed better. To work towards shortened calving intervals, producers will need to keep cows and heifers in good shape.
“The herd should be at or near a body condition score of 5, where only a faint outline of the last couple of ribs is visible, or none at all,” Andy McCorkill, livestock field specialist with the University of Missouri Extension, said.
First-calf heifers will keep up their body condition better if they can be fed separately from mature cows, prior to breeding and during gestation.
Dr. Eric Bailey, MU Extension State Beef Specialist, encourages producers to remember that heifers are still growing, and that appropriate extra groceries will set them up for success, both as first-time calvers and second-year cows.
Shorten the Breeding Season
To shorten the calving window, a producer must first shorten their breeding season. While many producers operate on a 60- to 90-day window, to really tighten things up, consider a 30- to 45-day breeding period.
“The use of a shorter breeding season is a great way to select those heifers that are more likely to go on to make great, reproductively-efficient, longer-lasting cows for your breeding herd,” McCorkill said.
To effectively breed the herd in 30 to 45 days, it is highly recommended bulls have a breeding soundness exam (BSE) and a semen test to ensure their good condition and fertility if a producer is breeding naturally as opposed to artificial insemination.
Synchronize Estrus
One method to shorten the breeding season, and therefore the calving season, is to synchronize estrus in the herd. This can be achieved by utilizing Controlled Internal Drug Release (CIDR) devices.
“For those beef producers utilizing some type of estrus synchronization, the use of a CIDR is very common. A majority of protocols include the use of the device,” Dr. Scott Poock, veterinarian and Associate Extension Professor with the University of Missouri, said.
Assistant Extension Professor and Beef Reproduction Specialist with the University of Missouri, Dr. Jordan Thomas, explained how the device works:
“The CIDR is a t-shaped piece of nylon that has flexible ‘wings’ that allow it to be loaded into an applicator. The t-shaped piece is coated with silicone, and embedded into that silicone is 1.38 gram of the hormone progesterone. The CIDR is loaded into the applicator, placed in the vagina, and remains in place for a period of time, usually ranging from five to 14 days, depending on the protocol schedule. During that time, progesterone is slowly released from that CIDR at a low level. Progesterone is a hormone a cow or heifer makes naturally during the luteal phase of the estrous cycle, so this is one tool we can use as part of an estrus synchronization protocol.” There is a $10 to $15 cost per device associated with this type of estrus synchronization, but for many producers the pros outweigh the cons in this area. “There is a lot of potential return on that investment,” Thomas said. “Getting cows or heifers pregnant early in the breeding season is one of the big drivers of profit in the cow/calf business.”
These steps can aid producers in achieving a narrower window for calving, and typically result in a more uniform calf crop, which has a number of benefits.
Consulting with a veterinarian can help a producer keep cows in good shape, acquire CIDR devices, and answer additional breeding and calving questions.
