PREPARING FOR A WINTER FORAGE CRISIS
The inclement weather for the past 2 months with seasonally high temperatures in October has created an impending fodder crisis in many areas of Ireland. Dairy herds have been housed by night and indeed by day in many parts of North Kerry, Clare and Galway for the past six weeks.
Grass growth rates have been excellent. However it has not been possible to graze this grass without prohibitive wastage and soil damage. Zero grazing has been used on many farms to successfully harvest the grass with minimal soil damage.
Grass is very low in dry matter. Over the past 6 weeks, grass dry matters have been as low as 10-12%. Silage is considered wet if less than 20% dry matter. We have had a very wet autumn with poor sunshine resulting in low/no sugar in grass. Low sugar grass equates to low energy levels. Autumn fertilizers have pushed protein levels up in grass but with the low energy there is an imbalance. Wet autumn grass has no fibre, therefore grass will not stay in the digestive tract long enough. Hence cows will scour and loose body weight. These are the reasons why grass needs to be balanced with appropriate ingredients in the correct proportions by a qualified nutritionist.
This scenario has been avoided on several farms visited by balancing the diet using high dry matter silage. Zero grazing has a place on many farms where farm fragmentation, excessive walking distances on the grazing platform and inclement weather increases the risk of soil damage and herbage wastage. The science of managing cows with zero grazing needs to be improved.
Zero grazing also increases the health risk of Neospora and Stomach fluke. Cows do not have the opportunity to selectively eat contaminated forage. These diseases are primary health risks associated with poorer reproductive survival of cows. Some of our clients in the North have switched back to harvesting more silage where these health risks are minimised. There are also less daily demands of a scarce labour resource. Grass silage will have less day to day variation in nutritive value which can be easily balanced using supplemental concentrates.
Current milk price will entice many farmers to milk their cows for a longer lactation this year. Indeed some farmers plan to milk their late calvers through the Christmas period. You need accurate ageing of pregnancies of you plan to reduce the dry cow period to the minimum of 8 weeks for mature cows and 12 weeks for first lactation cows and those carrying twins.
The opportunity to extend the lactation period primarily depends on managing body condition score. Supplemental silage and concentrates are a necessity at this stage of lactation when grass dry matters and grazing conditions are so poor.
There is an excellent profit margin to be made by harvesting late lactation milk with high solids concentration. This cannot be at the expense of a declining BCS. Your cow survival rate in the next lactation will be poor. Plan now on your forage requirements for the winter period. Remove empty cows from the herd if you have limited housing capacity. You should focus on a cubicle space for every cow and sufficient feed space for all the cows to access simultaneously. As cow numbers have increased, there has been insufficient regard for the water requirements of cows. You need to ensure adequate access points to water troughs and the use of rapid fill units.
Forage requirements will be a limiting factor on many farms this winter. There will be a need to supplement with concentrates or purchase forage from other farms. Plan a budget for these requirements now.
It is paramount that the 6 week period prior to calving and the first 2 weeks after calving encompassing the dry and fresh cow transition period are conducive to optimisation of dairy herd health. Our end of season herd scans are identifying significant numbers of cows in need of a 12 to 14 week dry cow period so that BCS can be restored to a 3.0 for a 6 week period pre calving.
Contributing factors include first lactation cows, cows in 5th and greater lactation with poor BCS, cows carrying twins and cows with poor locomotion scores. Lameness has become a major problem on many farms in the past 4 weeks. Farm roadways have been eroded with the continuous rainfall since August.
Dr Dan Ryan is a bovine reproductive physiologist and can be contacted at www.reprodoc.ie
Article written by Dr. Dan Ryan for the Farming Independent 24th of October 2017.