for years now dairy cows have been growing in stature, however that trend needs to be arrested to ensure efficiency. that was the message at a recent ahdb calf to calving meeting held in aberdeen.ahdb dairy technical manager andy dodd explained that a maintenance value had been added into the most commonly used breeding indices to try and stop uk dairy cattle getting any bigger. in time the value should see fewer very large cows being bred.while breeding indexes such as the profitable lifetime index (£pli) and the spring calving index (£sci) have always included key traits such as fertility, longevity and production, maintenance has been a more recent addition. using the genetics of the terminal sire it estimates the mature weight of the daughter compared to the average heifer which means farmers should be looking for a negative result.mr dodd said: “we don’t necessarily need cow size to reduce, we just need them to stop getting bigger and bigger. the maintenance value will estim...