Previous articles have emphasised the importance of good feeding and management during the transition period around calving, so early lactation management should build on a good transition foundation. Early lactation is a stressful time for dairy cows, as they recover from calving, rapidly increase milk production while losing body condition, and prepare for the next pregnancy. It is important to feed and manage cows well during this period, as this will set them up well for the rest of their lactation.
Most dairy herds start calving a month or more before pasture growth is at its maximum, so rely on winter conserved pasture (feed wedge) to feed their cows after calving. A risk is that if the quality and quantity are insufficient to match demand, especially in a late spring, then milk yield may suffer, and cows may lose too much weight, resulting in higher empty rates.
Many dairy farmers feed supplements during this period in the form of conserved forages, such as high quality inoculant treated silages, or concentrate feeds, such as meals, grains and by-products. Second round pasture is usually low in fibre but high in nitrogen (protein), leading to farmers offering their cows low protein, high starch or sugar supplements to help balance rumen energy and protein supply for rumen microbes.
A low fibre and high sugar/starch type diet may lead to sub-clinical or clinical acidosis, resulting in reduced milk yields, loss of appetite, increased weight loss and lower fertility rates. Options are to offer some long fibre (minimum 2.5 cm), a rumen buffer, or rumen specific strains of live yeast.
Specific strains of live yeast are increasingly being used, as more trials demonstrate their efficacy in improving rumen function and maintain appetite. Research demonstrates that rumen specific live yeasts promote growth of anaerobic fibre degrading microbes by scavenging oxygen, which in turn helps maintain a more stable rumen pH. The yeast may also act as a source of nutrients for rumen microbes. Live yeast cultures can be fed with silages or mixed with concentrate supplements or meals.
As featured in NZ Dairy Farmer