Letting your cows ride the wave

It has been an unusual spring so far, and quite a contrast to last season for most of the South Island. Late August-early September have seen double the usual grass growth rates and good weather conditions for calving cows and less metabolic problems in general, which is good timing for farmers who are currently experiencing financial pressure. Less silage, more pasture and higher intakes have resulted in an early and higher peak in milk production per cow. The peak delivery to the factory will depend on last year’s submission and conception rate in the first six to eight weeks of mating.

Quite often the 10 day peak period is mentioned in pubs and discussion groups. A peak of 2.4 kg MS per cow or 7.5 kg MS/hectare/day sounds really good, but the challenge is to hang on to this as long as possible and keep the so called “post-peak decline to a minimum”, ideally below a 5% drop per month. This is really important for the total production per cow and per hectare for the season.

Dairy farms in New Zealand differ substantially; this is dependent on geographical and individual farming factors. Geographical factors include weather and soil types. Farm management also creates vast differences between farms, such as farm size, cow numbers, fertiliser application per hectare, cow type and feed inputs. Maintaining pasture quality is the one factor that should be consistent, as this is crucial to ensure that the farm is able to keep riding on top of the wave for as long as possible.

The following practices will help achieve pastures of 12+ MJ ME and 20+ % protein:
Maintain grazing residuals between 1500 and 1600 kg DM/ha.

  • Surplus pasture on the milking platform should be taken out of paddock rotation and kept for baleage or silage. Mow these paddocks before they are two cans high, i.e within 10 days after leaving it out of the round.
  • If necessary to get residuals and quality back, top the paddocks or use another stock class to get the residuals back to target levels.
  • Applying nitrogen helps tillering and new leaf formation.
  • Walk around the farm with the whole team and explain what quality and target residuals look like so everybody understands what to look for.
  • Take some pre-grazing pasture samples and get them analysed for feed quality, so you get precise feedback on metabolisable energy, protein, fi bre, dry matter etc. If you test for minerals as well, this can give useful feedback for your fertiliser programme.

Don’t forget to stay on top of animal health issues:

  • Keep up the magnesium levels via the water and dairy pellets/meal or mineral concentrate pellets in the shed. What is enough on one farm may not be enough on another farm, due to the difference in production levels, pasture composition, etc. Talk to your feed specialist and ask your vet for blood analysis of the herd.
  • Ensure your herd has adequate copper, selenium, cobalt and iodine via the feed or water system.

Remember not to assume that what worked last year, will be sufficient this year. Have the cows wintered differently? Have you got more new pastures? Have you changed your fertiliser use?

The in shed feeding system can be a great help to control post-peak decline too, but should not cover up pasture management issues:

  • Don’t suddenly drop the feeding levels of grain, dairy meal or pellets. Look at cow condition, milk production and weather conditions before you decide.
  • Increase the level e.g. from 2 to 3-4 kg’s if a bad spell of weather comes through and ease out when conditions improve.
  • One or two bad spells of weather over the November/December period can cost you a lot of production on a yearly basis and can also undermine the results of your herds mating period.
  • If you run two or more herds, or have a system in which you can favour higher producing and/or skinnier cows, you can use the in shed feeding tool even more efficiently.

Keep on the ball and make sure your cows have every reason to keep riding that wave and get in calf as well!