ONE BREEDING PROGRAMME FINISHES HERALDS THE ONSET OF SPRING BREEDING IN 2014
The past month has literally put icing on the cake for dairy farmers in grass based milk production systems. The memories of a harsh summer in 2012 and spring of 2013 have now been overcome to a large degree by an excellent summer grazing season in 2013. The farming community has definitely learned lessons from the past eighteen months.
Farmers have taken the opportunity to harvest extra silage where available because of poor first cuts. The weather has lent itself admirably to enable the conservation of excellent silage, crops of barley and wheat and the prospects of a bumper crop of maize.
With spring breeding programmes now complete, it is time to evaluate what stock you will have for calving in 2014. It is essential to scan those cows not confirmed pregnant to date at least thirty days after removing the bull or the last AI date. Embryonic mortality will be significant up to day 35 of pregnancy. Less than 5pc of pregnancies will be lost beyond day 35, which is primarily accounted for by losses of twin pregnancies, followed by cases of Neospora and Samonella in later stages of pregnancy.
With the autumn grass growing season and grazing conditions set to exacerbate the risk of a super levy situation, it is paramount that action is taken to reduce the risk. Some farmers plan to put their cows on once a day milking, which will reduce milk output whilst maintaining output of milk solids. However, care has to be taken that SCC is not increased significantly.
In my opinion, one should now focus on the number of cows needed to fill your milk quota in 2014/2015 quota year. Identify those in-calf heifers and cows which will calve before the end of April 2014. If this number meets your quota, then you should evaluate your winter forage requirement making an allowance for a longer wintering period. Most farmers now accept that extra silage in the pit is no longer an “inventory cost” and safer than money in the bank!
It is essential to measure your stocks of forage now and consult your advisor if assistance is needed. Plan on this basis the most opportune time for the sale of empty cows and the retention or otherwise of late calvers in 2014. Empty cows may produce cheap milk until the close of the milking season, but at the expense of the breeding programme for the in-calf herd in 2014.
This brings me to the kernel of our management practices at this time of year. Our focus has to be one of achieving a body condition score (BCS) of 3 to 3.5 at the time cows are dried off. The big risk at this time of year is the production of cheap milk from grazed grass associated with the loss of body condition. High faeces passage rate associated with either lush grass after grass or heavy infestation of liver or stomach fluke have to be avoided as they will result in BCS loss. Tight grazing to either extend the rotation or avoid topping are unacceptable practices if BCS is compromised.
The ideal BCS achieved at the time of drying off has to be maintained until cows calve. Attempting to gain BCS when cows are within 2 months of calving is the wrong approach to next year’s breeding programme. It may be difficult to comprehend that management practices now can have an impact on next year’s breeding programme. However, there is research data, which clearly shows that cows which maintain an ideal BCS through the final two months of pregnancy have fewer cases of retained after births, calving difficulty and metabolic diseases around the time of calving, which in turn has been associated with subsequent improved reproductive performance.
Finally, we have just completed a study involving over 1,000 dairy cows, showing that adverse events either during the dry cow period or around calving were associated with significantly higher SCC in milk harvested between 13 and 22 days post calving. The cows in this study were grouped on the basis of a scan of the womb into healthy and unhealthy, with 35% of the cows classified as unhealthy and having significantly higher SCC.
Therefore, milk processability and ultimately milk process may in the future be dictated by management practices in late lactation prior to drying off. In essence, it is essential to have healthy cows at all stages of the production cycle to produce healthy milk which will give you healthy profits!
Article written by Dr. Dan Ryan in The Farming Independent September 3rd 2013.