Tighter joinings, how to get there

Managing joining periods in cattle herds should be clear cut - but, as most producers know, it often isn’t.

One of the chief challenges is not only maintaining a short, disciplined mating period but, in some cases, it is also trying ‘fix’ herds that have slipped beyond their optimum six to nine week joining window.

Cattle veterinarian Dr Alison Gunn, who is a presenter at this month’s MLA ReproActive workshop in Bairnsdale, Victoria, will advise producers on how to implement strategies to optimise their joining periods.

Here are some of her top tips for achieving tight calving intervals.

1. Discipline: Clarify the timing and length of the joining period and be disciplined about when bulls go in and when they come out. For southern production systems, the ideal joining period is six weeks for heifers and eight to nine weeks for cows, with heifers joined prior to the cow herd. A six-week joining for heifers applies selection pressure for fertility and gives them more time to re-join as first calvers.
2. Plan ahead: A cow’s breeding career starts at weaning. Aim to keep about 70% of the heifer drop and if numbers need to be reduced, remove the smaller, younger heifers. Weigh them at weaning and any heifers that will struggle to make the critical mating weight, (generally a minimum of 300-330kg for British breeds depending on frame size) should be separated and preferentially fed.
3. Dietary requirements: Adequate nutrition is essential for breeders to cycle and get back in calf on time. Following is a guide to minimum body condition scores, ranging from 1 (emaciated) to 5 (obese) for autumn and spring calving herds:

   

4. Bulls need to be healthy, sound, vaccinated and, at a minimum, have a Bull Breeding Soundness Examination (BBSE) with a crush-side semen check to ensure fertility. Once out with the mob, they should be inspected closely at least once a week.
5. Pregnancy test six weeks after the bull-out date so cull cows can be identified early and producers can explore their options.

Alison said once cows’ joining period slips back, it is very difficult to pull them forward again.

“The key to tightening a herd’s joining period is address the issue using heifers,” she said.

“Join as many heifers as you can for a six-week period and give this group preferential treatment for nutrition to maintain a body condition score of 3-3.5 to ensure they re-join on time.

“The overall herd will be younger for a few years but this will enable producers to cull cows that no longer fit within the eight-week joining period.

“The end result is shorter calving intervals, requiring less labour, that produce even lines of steers and heifers.”

The MLA More Beef from Pastures ReproActive Workshop will be held at Bairnsdale, Victoria on Tuesday, 19 July.

More information: Dr Alison Gunn T: 0409 144 825 E: info@herdsolutions.com.au

For more information or to register online go to http://www.reproactivebairnsdale.eventbrite.com.au by 18 July. Registrations prior to 15 July would be appreciated for catering purposes.