Herbage tests were taken on the monitor farms last week, with most of the results typical of the late spring/early summer period in most seasons.

The drymatter content of the pastures across the four Monitor Farms are showing a variety of levels. All drymatter levels are within the parameters of typical spring pastures but samples from the Opotiki and Awakeri Monitor Farm’s look to be trending towards the summer parameters already. As we head further into the summer months start thinking about summer management strategies.

Energy content of the diet is usually the most significant factor limiting cow production and the common perception currently would be that is the case. Based on these pasture samples, all of the Monitor Farms have pastures with energy contents at the lower end of what might be considered typical for this stage of the season. Based on these pasture samples, with a pasture only diet and cows being fed to requirements, the energy content of the Pongakawa pasture sample would be likely to limit milksolids production. It’s important to note that the impact would be less where cows were selectively grazing, but management of the remaining herbage would be important to ensure feed quality wasn’t further compromised.

In general, summer pasture will contain protein levels in excess of cow requirements through the mid lactation period.  Where protein levels are lower, milk production levels may become compromised. Overall, pasture protein levels should not be unduly limiting milk production levels.
Fibre is the final factor in the equation. When cows are grazing good quality pastures NDF content has only a very small impact on intake. This is because the NDF in good quality pastures is highly digestible and rapidly degraded. However, as pasture quality (energy content) declines, and digestibility levels decrease, NDF will play a bigger role in regulating intake. This combination is starting to exist across the Monitor Farms, and is more obvious in the Pongakawa pasture sample. With a predominantly pasture based diet, it would be likely that there would be some suppression of potential milk production.

Pasture is still providing a balanced feed and managed effectively will provide all the energy and nutrients that a milking cow requires through the summer period. Heading into a potential dry period, the focus needs to remain on ensuring pastures continue to be adequately grazed and stem content kept to a minimum.