As more and more farms install milking robots in Canada and the United States, research on those farms gives us more and more knowledge of what works and what might not in our production systems. In the past few months, there have been a few new research trials.
One trial looked at locomotion scores, hock lesion scores and hygiene scores on a number of farms in the U.S. Midwest. Cows were scored by a member of the research team. The researchers collected additional information about the farm, including production data.
The farms had two robots on average. The largest farm had eight robots. There were farms that had been purposely constructed for the robots, as well as farms with retro-fitted barns. There were a range of stall and bedding strategies that included sand-bedded freestalls, bedded packs, mattresses, water beds and mattresses with access to pasture.
Cows were scored for locomotion on a scale from 1 to 5. Cows were scored as lame if they had a score of 3 or more. They were scored as severely lame if they had a score of 4 or more. The percentage of lame cows differed according to bedding type. Barns with sand-bedded freestalls and bedded packs had significantly fewer lame cows than barns with other types of bedding. The farms with mattresses and access to pasture and farms with waterbeds had a similar number of lame cows. Their scores were lower than cows in barns that only had mattresses.
Looking at the percentage of cows with severe lameness (a score of 4 or more), there were differences between barns with different bedding strategies too. Barns with mattresses and waterbeds had significantly more lame cows than farms with sand-bedded freestalls, bedded packs or mattresses plus access to pasture.
There were differences in hock scores too. Barns with sand-bedded freestalls, bedded packs or water beds had fewer cows with high hock scores than barns with mattresses. Barns with sand-bedded freestalls or with waterbeds also had fewer dirty cows and severely dirty cows than all the other bedding systems. As you’d expect, manure removal systems also had an impact on the number of dirty cows. Manual manure removal had fewer dirty cows than barns with either automatic scrapers or slatted floors.
Another recent study looked at the impact of housing and management on productivity on 33 farms with robot milking systems, also in the Midwest. All the barns used free-flow cow movement management. Barns that used automatic feed push-up with a robot produced more milk (both per cow and per robot) than farms that pushed up feed manually. There were no differences in production between new versus retrofitted barns, between barns with different freestall surfaces or between barns with different manure handling. There were also no differences in productivity between barns with different numbers of robots per pen.
Amongst the management factors that were associated with better average milk production per robot were the average age of the cows, the cow-milking frequency, cow-milking speed, number of cows per robot and daily amount of concentrate feed offered per cow in the robot. Amongst the factors that were found to be associated with lower production per robot included the number of failed visits to the robot, the time it took to prep the udder before milking and apply teat disinfectant after milking and the amount of feed left after milking.
Both these studies show that barn design and management are just as important in robot barns as in any other milking system. Some of these factors can be anticipated during barn construction while others may only become obvious once cows get into the barns.
Dr. Robert Tremblay is a veterinarian for Boehringer-Ingelheim and lives near Guelph.