DTT Kavanagh – Autumn Calving Trial
Summer dry has been identified by farmers as being the most challenging climatic event in many coastal areas of the North Island. The average summer rainfall in coastal Taranaki is 240mm with evapotranspiration of 410mms. The result is long periods of moisture deficit, reduced pasture growth rates, and greater size and duration of feed deficits. In comparison, winter pasture growth rates have increased over the past 20 years, with more widespread use of urea and gibberellic acid, improved ryegrass cultivars, and increased soil temperatures (+1.6°C in 30 years).
To add to the incentive of feeding and milking cows during the winter, compared with summer, Fonterra and Open Country are actively pursuing more winter milk for UHT exports to China and short shelf life products that need to be made during winter. For example, Fonterra is offering winter premiums of $2.85 to $3.50 for the period 16 May to 15 July (less transport charges).
The current trial at DTT Kavanagh is investigating the benefits and costs of autumn calving. The Kavanagh farm is coastally located on the outskirts of Hawera.
- 2x 104 ha farmlets established spring 2017 – 4-5 ha paddocks randomized for soil fertility, location/block (equal number on coastal side of farm), and equal effluent paddocks
- Each farmlet 300 Friesian X cows – randomized, balanced herd based on age, PW, BW, LWT, calving date, MS production from previous season
- 300 cows mated in spring 2017 and dried off in May 2018
- 300 cows not mated in spring, milked through and mated in June 2018, then dried off in Feb 2019
Results 2017/2018 Season
|Kg MS/cow||Kg MS/ha||Days in milk
(up to 1 June 2018)
|Cow LWT (Kg)
Results 2018/2019 Season
|Kg MS/cow||Kg MS/ha||Days in Milk||Days in Milk
|Cow LWT (Kg)
Over the two transition years the autumn herd produced 107 kg MS/ha less than the spring herd.
Predicted production 2019/2020 Season
|Kg MS/cow||Kg MS/ha|
Overall, we see the benefits to an autumn calving system to include taking advantage of the winter premium milk price + the second flush in production/higher per cow production. Many farmers are also finding it to be a good lifestyle change. However, it does come at a cost with a greater amount of supplementary feed required to get through the winter feed deficit period.
Our trial is running for three seasons and we are yet to undertake a full financial analysis.
Feel free to follow the Kavanagh Farm Autumn Calving Trial progress via our weekly Farm Walk Notes, available on http://www.dairytrusttaranaki.co.nz/