Almost a quarter of heifers fail to reach target live weight at 22 months of age. These smaller animals are disadvantaged in the herd, often resulting in early culling.

Autumn is a crucial time to weigh heifers, checking that they have met their targets. By doing so, it is easy to identify the lightest animals for preferential treatment.

By nine-months old, heifers should be 40 percent of their adult weight, while pregnant rising two-year-old heifers should be at 90 percent adult weight at 22 months old. Weighing a sample of four to five-year-old cows in November and December will give you a good indication of the mature weight of the herd. Achieving targets now ensures the heifers reach puberty and cycle well at 15 months. Staying on target, they should then calve down at 24 months having achieved healthy growth.

Reaching target requires live weight gain from weaning through to two years of age of between 700 to 800 g per head per day. Maintaining growth rate targets in summer dry regions can be more challenging, but all regions suffer from underperformance.

Contributing factors include a lack of feed quality not delivering enough energy and protein within a balanced diet, sufficient dry matter intake, parasite challenge and trace element deficiencies.

Supplementary feed is a good way to correct energy and protein deficits. Identifying the deficits first helps you choose the best supplement. Specialist forage crops can also be effective. Pasture cover assessments and feed herbage testing are useful tools to identify where the deficiencies are.

Parasites in autumn can be a problem, especially where calves are grazed without older cattle in the system. Always use a combination product containing Levamisole so Cooperia worms are treated effectively. The best option is a triple oral combination product, repeated monthly until late autumn, then extending the intervals as good worm management in the summer and autumn reduces the need to drench from winter onwards. Cross-grazing with older R2 cattle helps reduce the parasite risk.

Pregnant R2 heifers can also suffer from worms with Ostertagia being the main culprit. Products from the mectin family are best, however, consideration must be made for any milk and meat withholds.

Trace elements programmes should be monitored via bloods or liver biopsies to check adequate levels and adjust where necessary. The key four trace elements for growth and reproduction are cobalt, copper, iodine and selenium.

Contact your local PGG Wrightson Technical Field Representative for assistance with formulating a plan to support your heifers to achieve target live weights.