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Feeding and nutrition play a critical role in a young heifer's development. A well-fed heifer grows more, produces more milk, and competes better with mature cows. Your heifer's diet needs sufficient energy and protein for optimal growth. A balance of minerals and water availability is also vital. Growth rates can guide you on whether you're meeting your heifer's nutritional requirements. Ryegrass pastures can fully satisfy a heifer's dietary needs. Monitor your heifer's weight gain to ensure you're meeting her nutritional needs and providing enough minerals and water. Good pre-puberty nutrition influences skeletal growth. Adequate energy and protein intake support both growth and maintenance. When it comes to supplements, use them wisely as over-reliance can be uneconomical and risky.
Feeding and nutrition is vital for the growth of young heifers. Well-grown heifers will produce more milk, compete better with mature cows and survive longer in the herd.
Well managed ryegrass pastures are a complete diet for heifers at all stages of life, including leafy kikuyu pastures. Heifers should be fed diets greater than 10.5MJ ME per kg DM and the appropriate protein to ensure that they meet liveweight targets.
Heifer liveweight gain is the best indication of meeting nutritional requirements as well as adequate minerals and water provision. Farmers should focus on meeting key weight for age liveweight targets for heifers rather than a particular pattern of weight gain.
Nutrition pre-puberty (before 50% mature liveweight) is where skeletal growth is influenced, if R2 heifers are significantly shorter than mature cows pre-calving it will be due to feed management pre-puberty.
Energy and protein required (eaten) for maintenance and growth in heifer diets.
|Liveweight||Maintenance||Growth per 1 kg||Protein|
|Kg||MJ ME/day||MJ ME/day||%|
*Energy does not account for energy required for pregnancy
The required protein percentage of the diet declines as the heifer gets heavier because the relative weight gain slows down. For example, a heifer would double her liveweight in her first three months of life, but typically it takes another nine months before she doubles her weight again.
The below table shows the required daily feed intake
|Start weight||DM intake for different rates of Lwt gain (kg/hd/day)|
*This table is for feed eaten, feed offered needs to account for wastage.
*This table does not include walking/ hard hill/ unfavourable weather and is based on feed quality of 11MJME/kg.
Add/subtract 10% per MJME for diets below/above. Add additional 5% for rolling to steep land.
*Pregnancy requirements: Requirements for different stages of pregnancy based on calf born at a weight of 30 kg. 1705 total MJME for pregnancy (assumes 11 MJME).
|Weeks before calving||-12||-8||-6||-4||-2||0 (due date)|
The below table shows the average required daily water intake of heifers
|Bodyweight (kg)||Litres per day|
Mineral requirements of growing young stock will vary by farm and region. Look at soil types, pasture fertiliser history, and types of crops or supplements being fed. Speak to your vet about developing a mineral supplementation plan.
Supplementing pasture may be required to maintain heifer growth. If pasture is limited, it is cost effective to feed heifers crops and supplements. Supplements for pasture diets should contain at least 11 MJ ME/kg dry matter and crude protein suitable to meet the animal’s nutritional stage.
Animals may gain slightly more weight from supplement feeding, but the weight gain is rarely economical. Supplementation may be justified if heifers are behind liveweight targets and need to achieve weight for age targets before the end of a contract. Short term supplement feeding can also be beneficial if it helps increase pasture growth rates to fill feed shortfalls and reduce the amount of supplement needed overall.
You may see an increase in heifer liveweight gain from crops or supplements, this is a result of increased feed supply, not an increase in feed quality or crude protein content.
Feeding crops and supplements will reduce animal health risks associated with pasture (such as ryegrass staggers) but have risks and limitations of their own.
Crops and supplements typically require rumen transition and may have issues with palatability, nutritional composition, mineral composition, differences in feed management, suitability to the wider system, or low yields. Take these aspects into consideration when choosing a crop or supplement to feed.
Nutritional considerations of crops and supplements
It is dangerous to rely on compensatory growth as it varies for each animal. Compensatory growth rarely makes up the difference for mobs to meet target weights and fails to close liveweight gaps. Using supplements and crops when pasture is limited increases the chances of heifers reaching target weight.