Better mating performance across the herd

Better mating performance across the herd

24 September 2019

When it comes to herd fertility, it pays to take special care of heifers in order to set them up for a productive life.

Being mindful of industry targets and adopting a considered nutritional approach for the entire herd will pay dividends throughout the coming lactation season and beyond.

It’s the time of the year when the dairy farming focus shifts towards achieving a strong in-calf rate. After all, a farm’s profitability is inherently linked to the reproductive performance of its herd. As a result, cows that don’t readily get in-calf represent the problem of delayed calving, and high empty rates are ultimately a cost to the business.

Industry in-calf targets recommend 76 percent of cows should be in-calf within the first six weeks of mating. However, in order to achieve this, it’s important to be mindful of the underlying fundamentals


“First and foremost, the cow’s metabolism is already performing at its extremes,” explains Paul Sharp, SealesWinslow’s Science Extension Officer. “Keep in mind she has just grown a calf and started lactation while her uterus is contracting and her rumen is expanding.” This massive metabolic load means she simply can’t cope with additional stress such as insufficient quantity or quality of feed. Should this occur, the very first casualty is invariably the reproductive function.

To minimise delayed calving and/or empties it’s crucial to adopt a nutritional approach that ensures feed consistency in terms of both quality and quantity. Ensuring ongoing feed availability and providing additional rations if the weather turns hostile is absolutely critical to promote timely cycling. What’s more, cows should be on a rising plane of nutrition with a high-quality feed allowance (four percent of liveweight) which will help them achieve better condition through mating.

As first-time mothers, heifers naturally demand some special care and attention. “They need dedicated nutritional attention because it’s liveweight rather than age that determines when a heifer reaches puberty,” says Paul. “For best conception results to occur, heifers should be 60 percent of mature liveweight at 15 months.” Feeding levels need to be managed appropriately to ensure heifers reliably reach their mating target weight.

This significantly contributes to good production levels in the first lactation with better mating performance and enhanced animal utilisation.

To address any pasture shortages and reduce energy deficits, Paul recommends keeping high-energy feed on hand. SealesWinslow’s Hi Energy Hi Starch is a pellet option containing a range of starches with different breakdown rates. The upshot is a longer availability of starch and a more stable and efficient rumen environment. Additionally, this superb pellet also contains bypass fats which provide targeted energy tailored for cows to get in calf and maintain pregnancy.

Lastly, the lead-up to mating is also the perfect time for boosting the metabolic performance with minerals. Make a beeline for trace elements such as copper, selenium and iodine as they provide essential support for strong heats and help conception to take and hold. These minerals are especially important as they are often deficient in New Zealand soils yet can be easily supplemented with a quality formulation such as SealesWinslow’s water-soluble Micromax range. It is specifically formulated to offset regional pastoral deficiencies in our soils and includes a concentrated blend of micronutrients to support the metabolism and immune system in the month prior to calving through until the second round of mating. The range even includes an option with organic copper – ideal for situations where high levels of iron in the soil inhibit copper absorption.

To discuss your nutritional strategy for improved mating success, head to your local Farm Source store or visit

Article supplied by SealesWinslow