Results in for high input vs low input trial

The second season of the high-input vs low-input systems management trial on the Stratford Demonstration Farm is near the halfway stage and there have been some interesting results so far.

After a moderate winter, the spring has been up and down with the low-input herd a little ahead of last season in production, but with lower levels of supplementary feed made, while the high-input herd is well ahead in production, but has brought in much higher levels of supplements. The high-input herd has also had the use of the covered feed pad and stand-off shelter for the season.

The current EEE farmlet trial on the farm aims to determine the economics, efficiency of feed use and environmental effects of two widely different dairy farm systems. One farmlet is a low-stocked self-contained system on all grass feeding with no brought-in supplements except replacement stock are grazed off. This is system one under the DairyNZ classification system. The aim is to be lower stocked at 2.8 jersey cows per hectare to make use of modern genetics and good feeding to achieve high per cow and good per hectare production and have a very profitable system with low environmental effects per hectare. The other farmlet is a high-stocked high-input system with high levels of brought-in feed.

The aim is to use most of the pasture grown by milking cows, buy in feed to achieve high per cow production, very high per hectare production and a high profit while minimising environmental effects especially on a per kg milksolids basis. This is system four under the DairyNZ classification system. The stocking rate is 4.1 jersey cows per hectare this season.

Winter this year had moderate pasture growth and conditions.

The low-input herd was wintered on grass and grass silage and got through the winter without doing much pugging damage but had a few nights stood off. The main damage was done during wet August conditions when the cows were calving and not able to be put on the yard overnight. The high-input herd spent the winter and over calving on-off grazing spending four to nine hours on the paddock getting grass then were on the covered stand-off pad for the rest of the day with maize silage and palm kernel supplement. They ended up being fed 26 per cent more than the low-stock herd over the winter putting on more weight and condition ending up at a high 5.4 condition score at the start of calving compared to 4.9 for the low-input herd.

The early spring was warm with very good pasture growth. The low input herd required no supplement surviving well on all grass feeding and having some silage left over. The high-input milkers have been fed maize silage and PKE through the spring on the covered feed pad but have spent the rest of the time in the paddock. The milkers have generally been getting 3 to 4 kg DM/cow/day of supplement and this herd has used a very high 900 kg DM/cow and 3700 kg DM/ha of brought in supplement up to early December which is 50 per cent ahead of last seasons use. Cool weather from mid September to mid November has restricted pasture growth.

There has been enough grass to feed the cows well but levels of surplus grass for supplements have been low. The low-input herd has harvested 25 per cent of the farmlet but have only made 140 kg DM/cow of silage which is 40 per cent of last seasons level at the same time.

Stock performance has been good for the spring. The cows calved at a very good rate over the first six weeks then had a lull in mid-September, but were all calved by the start of October. This year's mating has also gone well to date with very high submission rates from both herds. The condition score advantage of the high-input herd has reduced, but they are still have a very good current condition score of 4.7. Milk production has been around 1.7 kg ms/cow/day and 4.8 kg ms/ha/day for the low-input herd and 1.95 kg ms/cow/day and 7.8 kg ms/ha/day for the high-input herd over the mid-September to mid-November period. Total production to the start of December for the low-input herd is 162 kg ms/cow and 463 kg ms/ha and is 1 per cent ahead of last season while the high-input herd has done 188 kg ms/cow and 740 kg ms/ha and is 16 per cent ahead of last season.

These levels should be about 45 per cent of final production as long as there is no drought and the low-input herd has enough supplements made to milk on into May.

We look forward to evaluating the economic results at the end of the season to see if the extra milk production pays for the high level of supplements used at this seasons predicted milk payout.

Graeme is Farm Management Consultant at the Stratford Demonstration Farm.