Optimising Fertility Post-Calving

The late spring has resulted in a lack of grazing for a lot of farms. As a result, in spring calving herds fertility could take a hit if feed intakes are restricted and cows start to lose body condition in the lead up to service.

For vets discussing with clients post-calving management strategies to achieve fertility targets, it is worth considering the role of micronutrient supplementation, particularly with sources high in iodine.

Micronutrient status

Trace elements and vitamins play a crucial role in breeding performance. It’s particularly important to ensure iodine levels are maintained before and after calving to support early foetal growth and calf development through milk produced by the cow.

Iodine is also essential for hormone production, which is key in preparing cows for service. It’s recommended farmers work alongside their vet to identify and manage ‘at-risk’ cows that had problems while calving down, such as difficult births or metabolic disease.

These cows will be particularly vulnerable to nutritional imbalances ahead of the breeding season and, as such, are prime candidates for poor fertility.

In conjunction with iodine, manganese, zinc and copper also help optimise fertility as well as strengthening bone structure and enhancing muscle development.

And other trace elements, such as selenium and cobalt, work with vitamins to support a healthy immune system and drive milk production.


With an increasing number of herds transitioning to lower-input, grass-based systems, supplementing micronutrients using boluses is becoming very popular due to its convenience.

Although some labour is required to administer boluses at the outset, farmers can then have peace of mind that cows out at grass are receiving a reliable and consistent supply of nutrients every day for the duration of the grazing period.

This is particularly important for spring calving herds, which will be going back to the bull in the coming months.

To ensure a reliable and sustained delivery of trace elements and vitamins daily, it’s important to select a bolus with a single point of erosion, such as BriniBol®.