Time to stop breeding cows and manage milk quota
Article by Dr. Dan Ryan published in the Farming Independent July 26th 2011
It is now time to stop breeding cows for Spring-calving in 2012. Cows bred now will calve in May next year. In previous years there was a market for late calvers. However, as the number of breeding stock has increased dramatically we are now faced with the risk of a superlevy over the next four years.
Farmers are taking action now to avoid a superlevy. Stock bulls are being removed earlier. We are being booked to scan herds of cows from the middle of August to identify empty cows for culling. There is little point in living in hope that a superlevy will not apply.
With EU quota year starting in April and Spring calving starting in late January, there is too much scope to increase milk production with an increased number of first lactation cows coming into the national herd.
Plan now to match your cow numbers with quota available. The welfare of both stock and staff managing the herd hinges in this match. Increased cow numbers require an investment in land, housing and qualified staff to manage same.
Body condition management
Many farmers have resorted to options of once a day milking and removal of concentrates from the diet. This will reduce the level of milk production and maximize profit from same. However, if body condition scores suffers, it will impact negatively on your breeding programme next year.
Your cows need to gain body condition at this stage of the production cycle. Too many farmers get hung up on strict grass-based milk production. If the cow has a genetic potential for milk production above 22 litres at this time of year, grass alone will result in body condition score loss. There is also an issue of insufficient fibre in grass-based diets where cows are on after grass. We have several clients reporting butterfat percentages dropping close to their protein percentage with outbreaks of acidosis.
Target pregnancy rates
Pregnancy rates for Spring calving herds based on scanning vary enormously. Currently we record the pregnancy rate based on cows fit for service 21 to 45 days prior to the scan and an overall pregnancy rate for the period 21 days prior to scanning. The target of 90% calving in a 10 week period is no longer realistic on the majority of grass-based dairy farms Pregnancy rates have decreased by the order of 15-20% over the past 20 years. Crossbreeding, which introduces hybrid vigor has helped reverse this trend.
However, excellent reproductive performance can be achieved with Holstein Friesian cows if management skills are good. To date we have recorded ten week pregnancy rates in excess of 85% in dairy herds of Pat Cotter, Coolnakilla, Fermoy, and Danny Bermingham, Doonbeg, County Clare. Both of these dairy herds milk 68 and 80 cows respectively. In both of these case studies, the cows had excellent body condition scores and lameness was not an issue at the time of scanning. AI was used for breeding for the first six weeks of the breeding scan and a stock bull was used to breed cows failing to settle in calf to AI. Embryonic death was not an issue on either farm. Concentrates were fed to cows based on their genetic potential for milk production.
Embryonic death in dairy cows
The nail in the coffin, and where you feel like the grim reaper scanning cows, is reporting a high incidence of embryonic death. This can quickly reduce your results from AI to C3!. In these situations, we require further investigation using blood and bulk milk samples. Both stomach and liver fluke outbreaks are currently common on many dairy farms. These will result in depression of the immune system and outbreaks of IBR ensue.
Conclusion, aim to match your cow numbers with quota available. Ensure body condition score increases from now until cows are dried off. Identify and take action on diseases causing a depression in the immune system and a breakdown in your herd.