The results of research into accelerated calf rearing were presented at the Dairy On PAR calf roadshow in Tasmania last year. Calves that are fed ad lib (as much as they want) milk doubled their birthweight in just 42 days compared with 56 days for calves fed four litres of milk per day. This finding was part of a research project conducted at the Tasmanian Institute of Agriculture Dairy Research Facility in 2016-17 that compared three differing accelerated calf-rearing programs.
The ad lib calves also reached weaning weight an average of 10 days earlier than the control group fed four litres of milk.
Researcher with the TIA Dairy Centre Mark Freeman also spoke about the other two accelerated programs studied ù fortified milk until weaning and fortified milk for only the first four weeks. Milk is fortified by adding milk powder to the colostrum/fresh milk. Both of these programs also resulted in calves reaching weaning weight earlier than did the control group.
The group of calves fed fortified milk until weaning took an average of 80 days to reach weaning weight (the same as the ad lib group). The calves fed milk fortified for just the first four weeks took an average of 86 days to reach weaning weight. The control group took 90 days.
Extra or fortified milk is an additional cost to a calf rearing system, so it needs to be determined if it is worth it. This answer is yet to be determined.
Research conducted before this project has suggested pre-weaning growth rates account for up to 25 per cent of the variation in first lactation milk production. That is, the faster pre-weaning growth rates, the higher first lactation milk production.
This increased production is thought to be as a result of 'switching-on' genes during the pre-weaning period.
The heifers will continue to be monitored to see if the growth difference achieved in the pre-weaning period is maintained and whether there is a difference in milk yields once they join the herd.
This project was funded by a DairyTas small grant.
Article courtesy of Tassie Dairy News