The way New Zealand farmers approach calving is unique in that we tend to have a condensed calving spread, with the majority of cows calving over the spring period to take advantage of increasing pasture growth.
This contrasts with a year-round calving approach in other countries where cows are housed and fed indoors.
Our farming system results in many calves being born and reared in a short period of time, which means having proven and scalable calf rearing systems is hugely important.
EpiVets and Fonterra recently conducted a study of 213 farms across nine regions to find out more about rearing and weaning strategies.
The results found:
Facilities
Eight different bedding types were used including woodchip, sawdust and sand. Over 80% of farms use a wood based product (bark chips, sawdust) as their calf bedding. Calf shelters provided, included permanent structures (e.g. barns), temporary shelters (towable shelters/shed) and natural shelters (trees, hedges, straw bales).
Feeding
87% reported feeding calves at least twice a day for at least three weeks.
Weaning
The most common criteria for weaning calves were weight (between 80-100kg), meal consumption (1-2kg per day) and age. The weaning approach varied significantly with some farms gradually reducing milk, others transitioning to once-a-day feeding, and others implementing a 'cold turkey' approach once the appropriate age, weight or meal consumption criteria was reached.
Practices related to putting calves outside
Most farmers determined calves could go outside based on weather (27%), age (24%), space in the calf sheds (19%) and size (19%). Around a third of farmers waited until 4-6 weeks after birth before calves were put outside, and most allowed calves to come back into the calf shed based on weather conditions and/or age.
Grazing management after weaning
Most farmers had dedicated calf paddocks on the farm (47%).
Monitoring growth and health
97% of respondents monitored the health and growth of their calves after weaning with visual inspection and regular weighing.
The researchers found many New Zealand farmers have focused on cost and time efficient systems for rearing calves which often results in feeding lower milk volumes alongside other forms of feed, but there is a growing body of evidence to support a move to higher milk feeding systems to deliver increased efficiencies and better calf outcomes.
"There is adoption of high milk feeding systems as research-based evidence of the benefits grow," report the researchers. "However, we still lack good data on weaning targets for New Zealand dairy farms: both for what targets should be chosen and how they are met."
The research highlighted the variability of systems and how important good data can be in driving improvements. "Regular weighing and collection of morbidity and mortality data, provides an indication of what is happening on their farm, and even better, benchmarking against others who may be doing things differently."
More details from the study will be published in Hoofprint, the magazine of the Dairy Cattle Veterinarians Society.
To discuss calving practices for your farm get in touch with your local Farm Source team.