Another season, another series of newspaper articles opining the dwindling reproductive efficiency of the national dairy herd. It’s a problem, a real problem. There are not really any insightful and learned generalisations that can be uttered on this topic, only that every farm is different. Virtually every herd can do with improving reproductive performance. System 1 to system 5, high producing cows to lower producing cows, once a day herds or robotic milking herds – it can always be better.
And that’s the crux of the issue, when examining reproductive performance, the issues on every farm are different and the emphasis on each issue is different. So, we must break down the process. Winter feeding, calving management, milk fever and ketosis control, trace element sufficiency, energy sufficiency and utilisation over calving and strong positive energy input leading up to mating.
Primarily, the first goal is to get cows bulling. In my view, the current expectation of 6 weeks for a cow to bull from calving is too long. It is entirely feasible for cows to bull within a month. Furthermore, (and herd size logistic aside) if you need anything expensive and electronic to pick bulling cows then cows are just not displaying heat strongly enough and this is indicative of a problem. Once we know we have cows bulling effectively and the heats are picked effectively we can then move onto bull side issues if necessary.
As the hoary old saying goes, “You can’t manage what you can’t measure”. So, for each of these aspects the extent to which these animal health conditions and energy balance issues are acting on the individual herd need to be measured. This can be done by dietary analysis, analysis of previous reproductive performance issues via, for example MINDA data, and milk production and quality data. Together a picture can be gleaned of the likely issues that need to be addressed to work toward better reproductive efficiency.
The answers can be as simple as a trace element deficiency or as complex as a fundamental system change. It may take a mindset change on feeding cows or provide the impetus for impending change. It may be simply fixed in one season or a may take a major infrastructure change over several seasons. No one said this was easy.
Our genetic companies have been outstandingly successful in selecting a productive cow. Perhaps the most profound impact has been that energy distribution is prioritised to milk production at the expense of most other physiological systems. Meaning that energy deficiencies and the factors that influence efficient energy utilisation will limit reproduction well before they limit milk production.
We have bred magnificent animals, we just haven’t quite figured out how to manage them yet.