Trial is currently investigating the benefit of autumn calving.
DTT Kavanagh
Farm Data
- 213 effective ha
- Adjacent to Gibson property
Background
Autumn calving is becoming popular along the coastal belt of Taranaki. Summer dry is the most challenging climatic event with average summer rainfall of 240 mms and evapotranspiration of 410 mms resulting in periods of moisture deficit and reduced pasture growth rates and feed deficits. Also winter pasture growth rates have improved over the past 20 years with more widespread use of urea and gibberellic acid, improved ryegrass cultivars and increased winter soil temperatures (+1.6 degrees C in 30 years). Fonterra is paying a winter milk premium of $2.85 to $3.50 for the period 16 May to 15 July (less transport charges).
Trial Design
The Autumn/Spring calving trial was established in October 2017. 604 mixed aged Friesian-cross cows were randomly allocated into 2 herds with 104 ha/farmlet to give a stocking rate of 2.9 cows/ha. The spring calving cows were mated from 4 October to 20 December (11-week mating period). Autumn calving cows weren’t mated in spring with mating period 10 June to 27 August 2018 (11-week mating). Spring calving cows were dried off early May according to a feed budget and BCS with calving starting 10 July. Autumn calving cows were milked through the winter of 2018 and were dried late January 2019 based on BCS, expected calving date and feed budget starting December 2018. Start of calving for the autumn herd was mid-March 2019, with dry off date 27 January 2020. Year 1 & 2 were transition years from spring to autumn calving. It is proposed that the trial is conducted for 3 more lactations.
Measurements
- Milk production from 4 weekly herd tests + vat measurements. Milk can be stored and collected from 2 separate vats & 2 supply numbers via Fonterra.
- Pasture growth from calibrated weekly visual estimation of all paddocks (2 weekly in winter). Pasture calibrations to be done at DTT Gibson
- Pre and post herbage mass measurements and estimated cow intakes
- Supplements harvested and fed.
- 4 weekly cow Liveweight and condition score.
- All animal health and cow fertility events
- Full financial analysis of both systems
A full analysis of the transitional year including production and profitability is currently been done by a DairyNZ Masters student.