An in-depth survey conducted on 66 dairy farms in NI has identified key factors that hold back daily liveweight gain in calves.

Results from the study by the Agri Food and Biosciences Institute and Queen’s University Belfast have recently been published in the scientific journal Animals.

It shows that the average weight gain for 369 pre-weaning calves on participating dairy farms was 0.57kg/day.

The researchers describe this as “comparable” to previous NI-based studies, but it is “lower” than other regions, such as Britain (0.79kg/day) and the USA (0.74kg/day).

Findings

A wide range of factors on participating farms that could potentially influence calf performance were investigated as part of the study.

One issue was cold temperatures, as reduced weight gain was associated with calves spending over 50% of the time below their lower critical temperature, which requires extra energy to be used to stay warm.

The study also found that reduced calf performance was linked to exposure to elevated airspeeds, also referred to as draughts, in calf sheds.

Another factor influencing calf weight gain was reduced dry matter levels in bedding in solid floor pens.

Interestingly, the survey found a trend where average weight gains reduced as the number of calves weaned each year on farms increased.

Also, farms that used manual milk feeding methods had better performance than dairy units with automatic milk feeders.

The researchers state that the results show that “management of the rearing environment” is important for optimising weight gain in dairy calves prior to weaning.