Earlier this year we sent out a survey to understand how long our farmers’ beef cows are typically mated in our region, how the animals perform during that time, and what trace element supplements they receive.
We thought you might be interested to see our findings!
We began by asking about heifer mating...
Responses showed a wide range in mating durations, from 20 to 133 days. After removing an outlier, the average mating period was 55 days, which equates to just over two and a half oestrous cycles.
As shown in the graph below, you can see that leaving the bulls with heifers for longer has a slight correlation to higher in-calf rates. However, it’s worth noting that many farmers with shorter mating windows still achieved excellent results.
The graph below illustrates the distribution of in-calf rates among heifers. Across the sample, the average in-calf rate was 92%, though results varied widely. Encouragingly, around one-third of farms achieved in-calf rates of 95% or higher – which is an amazing outcome.
Next, we looked at mating periods for mixed aged cows...
The duration ranged from 31 to 141 days, with an average of 66 days (just over three oestrous cycles).
As shown in the graph below, extending the mating period beyond 80 days resulted in very few additional pregnancies. The relatively flat dotted trend line indicates that the length of joining has little to no correlation with in-calf percentage rates.
The graph below illustrates the distribution of in-calf rates among mixed aged cows. Amongst the cows in this survey, 64% achieved in-calf rates of 95% or higher. The overall average in-calf rate for mixed aged cows was 94%.
Then, we also asked farmers what supplements they had used for their cows over the past 12 months...
Responses varied widely, from no supplementation at all, to salt licks and more comprehensive approaches, including copper, B12, selenium, and iodine via injections or capsules.
14 out of 22 farmers reported applying selenium prills on their farms, and half were using injectable forms of selenium (such as Selovin long-acting, Multimin, or B12 with selenium). Of note, some reported use of both prills and other supplementation of selenium.
Results showed a lack of trace element testing, with over 80% of those surveyed not testing for selenium levels in the past 12 months.
By testing your animals' current trace element levels, you can target the necessary supplementation and methods to support their health, growth and production – while gaining more control over your animal health spend.
With so much variation in farmers’ approaches, it was impossible to pinpoint a single best practice...
This highlights that achieving good in-calf rates in cows and heifers is influenced by many factors – and we'd certainly recommend more regular trace element testing of your animals to make sure what you're supplementing or not supplementing is appropriate.
We’re always happy to discuss your cattle performance with you (even if our conversations often get sidetracked with talk of sheep!).
We carried out this survey after hearing reports from parts of the North Island indicating poor scanning results in beef cows, which were linked to selenium deficiency. However, none of the respondents to our survey reported that their cows had tested low for selenium, and it was not identified as a concern in our area.
A big THANK YOU to the 22 farmers who took the time to complete our survey! We hope you find these results useful and interesting. It’s always valuable to have local data to benchmark your own herd’s performance.
