Maternal Matters: Nutrition for heifers

Studies have shown that poor nutrition between weaning and breeding can result in fewer heifers reaching puberty before the start of the breeding season, as well as reduced conception rates and higher pregnancy loss. Therefore, getting nutrition right is key to a successful heifer development programme.

To successfully calve heifers at two years of age, it is recommended that they reach 65% of their mature weight before breeding: if your cows weigh 650kg, heifers must weigh 420kg before having access to the bull.

Suckled heifers should easily achieve one kg/day whilst on their mothers, which means they have to grow at approximately 0.7 kg/day, post weaning to reach the necessary weight before the breeding season.

Getting heifers to reach 65% of their mature weight before 15 months of age can be difficult if nutrition during their first winter isn’t optimal.

Between weaning and breeding, heifers need to have a steady growth rate of around 0.7 kg/day. This can be achieved by feeding good quality silage, and an additional 1-2 kg of concentrates.

Find out more about producing good quality silage using AHDB’s Silage Production Manual.

Feeding concentrates does increase development costs, but compared with the value of an additional calf, it really is worthwhile. When supplementing with concentrates it is important to ensure there is enough feed barrier space for all heifers to feed at the same time. This prevents bullying and variations in growth rates.

Once the winter housing period is over, focus on ensuring heifers are turned out onto quality pasture, to ensure heifers continue growing up to the breeding season.

To learn more about producing quality pasture, take a look at our AHDB Grass page.

Inadequate maternal nutrition at any stage of foetal development has been shown to impact calf development. This produces calves with lower birth weights and which have a higher chance of morbidity and mortality.

Even though most of the foetal growth occurs during the last trimester, most of the placental growth happens during the first two-thirds of gestation. Therefore, any disruption caused during this stage can have a big impact on future development of the calf.

Approximately 75% of calf losses from breeding to calving are due to early embryonic loss. The embryo does not attach fully to the uterus until 42 days after fertilisation, so any dietary changes during this time can impact embryo survivability.

It is recommended that nutrition and management of heifers remains constant for at least six weeks after the breeding season ends to prevent early embryo loss.

By the time heifers approach calving, they should weigh 85% of their mature cow weight. This means they must grow at approximately 0.5 kg/day between breeding and calving.

Pre-calving nutrition is crucial to ensuring heifers breed successfully again within a 365-day period. Heifers have a naturally longer post-partum interval (time between calving and first oestrus) which is heavily influenced by body condition score.

Studies have shown that thin heifers have a 30-day-longer post-partum interval than those heifers calving in good condition. This reduces rebreeding success because thin heifers often don’t cycle again before the start of the breeding season.

Thin heifers at calving are also more likely to encounter calving difficulties, resulting in an increased risk of calf mortality. Colostrum quality and quantity is also impacted.

Further information on feeding heifers can be found in the Managing Heifers For Better Returns.

Formulating a ration is not easy and often requires nutritional expertise. A ration must supply three key components:

1. Energy – maintenance and weight gain
2. Protein – for growth
3. Fibre – to keep the rumen functioning well

Depending on the animal’s particular life stage, the components will differ slightly.

Feed is a vitally important input to livestock production systems. It makes up most of variable costs and contributes to determining how well animals perform and the profitability of the system. This guide covers a range of feeds (excluding forages) that are suitable for beef and sheep rations. 

Grass grown for silage has different needs to grass grown solely for grazing. Silage can provide high quality forage for winter feeding. However, as with all crops, it depends on using the right varieties of grass and optimising soil conditions. This manual covers the key issues when making silage.  

The latest grass growth and quality figures can be found on our interactive dashboard, along with the latest updates and resources.