A gradual increase in concentrate feeding over the first 21 days of lactation is recommended in the latest AgriSearch booklet.
Just published, this is the 30th farmer’s booklet from AgriSearch, the NI Agricultural Research and Development Council.
In practical farmer terms this booklet reveals the results of three separate trials examining early lactation concentrate build-up strategies.
One of these trials was an on-farm study conducted by AgriSearch and AFBI on five farms across Northern Ireland. All three studies were co-funded by DARD and AgriSearch, with the on-farm study being funded through DARD’s Research Challenge Fund.
High yielding dairy cows are unable to consume enough food in early lactation to meet their energy requirements, and may enter a prolonged period of negative energy balance. This is reflected in loss of body condition, and is also associated with metabolic disorders, lower immunity and a decline in ‘functional traits’ such as health and fertility.
To help meet their higher energy requirements, the quantity of concentrates offered to cows is normally increased rapidly in early lactation.
However, high yielding cows may increase their milk yields in response to the additional concentrates offered, and this may actually make the situation worse. In addition, feeding more concentrates will reduce the amount of forage that a cow consumes, and these two factors can lead to rumen health problems.
It has been suggested that these problems might be addressed by introducing concentrates into the diets of fresh calved cows at a slow rate, and by reducing the protein content of the concentrates offered. A slower or a delayed build-up of a lower protein concentrate might slow the rate of increase in milk production in early lactation so that it better matches the cow’s energy intake, thus reducing the extent of the negative energy balance. In addition, this approach should increase the amount of forage in the diet, thus reducing the risk of rumen problems.
To examine this concept, the three aforementioned studies were undertaken by scientists at AFBI Hillsborough.
Based on the results of the three experiments a ‘moderate’ build-up strategy, based on a gradual increase in concentrates over the first 21 days of lactation, is recommended.
Electronic copies of the booklet can be downloaded from www.agrisearch.org or to request a hard copy email firstname.lastname@example.org or telephone (028) 8778 8206.