SBW Fall 2021 Sect. I
8/24/21
9:28 AM
Page 20
Tightening Up Calving Season By Olivia Amundson
One of the most important indicators of success in a cow-calf herd is reproductive efficiency of that population. A major profit-determining factor is the percent of calf crop weaned. This is accomplished through incorporating a shortened and defined breeding and calving season. According to USDA APHIS, (2008) 54.5% or one-half of operations from 24 states failed to have a defined breeding season. Cultivating uniformity of a calving season can be the first step toward improving production efficiency.
Cultivating uniformity of a calving season can be the first step toward improving production efficiency. Photo taken at Tom Brothers Ranch by Ellen Tom.
What is calving distribution?
calving interval: •When the third mature cow (3years-old or older) has calved or: •Begin the first 21-day period 285 days after the start of the breeding season.
Calving season can be defined as the number of calves born within a 21day calving period. Ideally, 60% of the herd should calve within the first 21-day period. According to the Standard Production Analysis Guidelines there are two ways to start the first 21-day
How do we fall out of a shortened calving season?
son cows are culled from the herd. Instances such as illness, injury, poor cow nutrition, depressed body condition score, and extreme weather events are some reasons cows fail to rebreed or become pregnant late in the breeding season. If there is not a defined calving season in place cows slowly fall farther and farther out of the assumed calving period.
Cows fall out of a defined calving season for multiple reasons. Reproductive failure is the number one rea-
Uniformity of calving produces multiple benefits for the production herd.
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Fall, 2021 • SIMBRAH World
Why is it important?
