Replacement heifers

Every spring we see groups of young heifers entering herds that are not quite where they need to be with respect to size, weight and body condition.

We know the consequences of light heifers at mating – more empty heifers and delayed first calvings. And we know the consequences of light heifers at calving – less milk produced in the first season (therefore lower life-time milk production), reduced fertility at second mating (therefore lower survivability in the herd), reduced ability to compete with larger mature cows for feed (therefore driving further weight loss) and what some farmers will find the worst scenario at the start of spring – heifers having trouble calving.

How do we avoid this?

Out of sight out of mind can be a problem with young heifers out grazing at a run-off or at a grazier’s property. Having a structured plan with respect to feeding, live weights and animal health and management is crucial to success.

There are heifer live weight targets at certain ages that are important to reach – (30% of mature weight at six months of age, 60% of mature weight at 15 months (mating) and 90% of mature weight at 22 months (pre-calving). They are important targets to reach because they give an indication that heifers are on track to reach puberty at 12 months of age, get in calf at 15 months of age and survive in the herd past two years of age. Targets also establish an agreed position for farmers involved in a contract grazing relationship.

Some of the most important aspects of growth (skeletal growth and udder development) occur at a young age. For an immature animal their feed conversion efficiency is greatest after birth and this quickly declines as they age. Therefore, pre-calving cow, calf, colostrum, meal and weaning management also play a major role in ensuring heifers reach target weights. Heifer growth and survival past weaning can be majorly affected by under feeding, low quality feed, parasitism, BVD, trace element deficiencies, pneumonia, IBR, Yersinia, lameness, pink eye, clostridial diseases and facial eczema to name but a few. Do you have a plan in place to maximise growth potential and to minimise the impact of animal health diseases?

If heifers are not weighed (scales or weigh band) and monitored regularly then how do you know targets are being met? If heifers are objectively (not by eye) weighed regularly then any check in growth can be investigated and rectified in a timely manner. During these weigh events animals can be sighted up close for animal health issues and these also investigated and rectified.

We can help you put in place plans to help you achieve well grown heifers at the start of their first calving. Just talk to your regular vet to get the process started.

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