It seems there are as many different ways of rearing calves as there are dairies. Every farmer has his or her way of doing things, and this results in a rich variety of practices, some of them effective, some of them less so. When you take the time and the care to measure performance – as every farm should - there are clear winners and there are farms that lag behind. See where you stand on some of the bad habits that hinder performance.
1. Missing important weight milestones
Body weight (BW) at 30, 180 and 450 days is linked to age at first service and age at first calving (Brickell, et al. 2009b). The growth rate from birth to 180 days affects the likelihood that heifers will achieve target service weight (380kg) by 420 days. Less than 10% of heifers with a recorded growth of < 0.5 kg /day at any time between 30 and 180 days achieved the target weight. Fewer than 20% of those whose growth rate 0.5-0.69 kg/day achieve this target. What's more, the mortality to six months is higher in calves whose BW is low at 30 days.
2. Achieving a mediocre first lactation
Optimal growth rates at 60 days of age correlate to high first lactation (every extra gram of weight gained prior to weaning translates to 4 extra litres of milk). Coming in at a lower weight will translate to less volume at first lactation.
3. Insufficient attention to price and performance
The cost of rearing heifers is high, representing about 20% of dairy farm expenses and making it the highest variable cost after feed. The return on this investment does not occur until the second lactation. In the UK, replacement costs average around 2.6 pence per litre (ppL), (€0.36, USD 0.39), but for many herds these may be 23% higher. By keeping careful track of price and performance, farmers should be able to lower this price to 2 pence (€0.28, USD 0.30).
4. Paying a surplus for late first calving
With these costs in mind, the age at first calving will clearly impact price. The difference between 0.79 kg/day and 0.63 kg/day growth rates results in calving at 2 years (vs 2.5 years at the slower growth rate). This in turn translates to savings of USD 290.60 if the higher growth rate is achieved.
5. Poor colostrum management
Colostrum management requires vigilance on a number of fronts. Dropping the ball on good colostrum management can have a lasting impact on the health and productivity of your cows. The goal is for >50g/L IgG. But also, colostrum must be collected quickly (under 2 hours after parturition), it must be collected hygienically, and stored appropriately. Maintaining colostrum or milk from the cow for the first three to four days will facilitate gut maturation. This in turn will improve pre- and post-weaning feed efficiency significantly.
6. Insufficient milk quantity, consistency or quality in pre-weaning stage
The liquid feed diet (WM or CMR) should provide up to 900-1200g/day DM with hygienically sound milk reflecting the right composition, right consistency and served at the right intervals. Whole milk or CMR may be used, but both must meet strict criteria. Natural variability in whole milk composition and the risks of disease and antimicrobial resistance with discard milk can be barriers to calf performance. CMR should consist of 22% protein and 19% fat and must feature good consistency and digestibility.
7. Inappropriate roughage/concentrate supply at weaning
A successful transition from liquid feed to calf starter is essential and must be managed carefully, particularly for calves transitioning to calf starter from high-growth-rate liquid feed diets. Factors impacting success are palatability, the physical form of the calf starter, fresh forage and the availability of plenty of fresh water.