Research highlights from 2017 ADSA meetings - calves and robotic milking
We have been conducting research at the University of Minnesota on dairy automation in recent years, especially automated milk feeders for preweaned calves and robotic milking systems for dairy cows. At the recent ADSA meetings in June 2017 there were a few abstracts presented on these topics and this article will summarize some of them.
Researchers from the Universities of Guelph, British Columbia and Minnesota (I am a collaborator) presented preliminary results of a study being conducted in Canada using data recorded by automated feeders to help detect sick calves. Sick calves had reduced milk intake as compared to healthy calves up to 5 days before treatment administration and their milk intake returned to normal 5 days after treatment administration. Another measurement that differed between sick and healthy calves was drinking speed. It decreased with disease and increased after treatment as well; however, it was not as noticeable as milk intake. It was concluded that milk intake can be a useful variable for producers to follow because they can observe how milk intake is affected by disease and recovery after treatment.
Another study from the same group of researchers investigated the association between farm management factors and prevalence of disease in group-housed calves fed with auto feeders. The median prevalence of scours within herd was 24% (range: 8 to 46%) and the median prevalence of respiratory disease was 14% (range: 3 to 31%). Main factors that can help reduce disease included: use of individual maternity pens; use a barn exclusively for milk fed calves or young calves (no older calves housed in the same barn); feeding probiotics, vitamin E and selenium to the calves; clean, dry, deep and comfortable bedding; feeding high quality milk, low in bacteria counts and appropriate percent of total solids. Cleaning the auto feeder and all parts must be a daily routine.
A study at the University of Minnesota investigated which farm management factors were associated with calf feeding behaviors at the farm level. We found that peak milk allowance, age difference among calves within the group, and age at weaning were positively associated with drinking speed. Milk allowance was also positively associated with the number of rewarded visits (when milk is fed by the auto feeder) and negatively associated with the number of unrewarded visits (when no milk is fed). What this means is that the more milk we feed the calves, the more satisfied they are and they do not keep coming to the auto feeder trying to get more milk. They will rest more hours per day. It is important to establish a gradual weaning protocol when feeding higher amounts of milk so that calves eat more starter feed prior to being weaned off milk completely.
A study at the University of Guelph investigated the use of anesthetics during caustic paste disbudding. Studies have shown that anesthetics and analgesics are effective on reducing pain with thermal disbudding but there is very limited research with caustic paste. Their study showed that caustic paste appears to cause pain for at least 180 minutes after application. Calves that received a local anesthetic nerve block prior to paste application had less pain sensitivity than calves that received a caustic paste containing anesthetic or calves that received a saline solution prior to paste application. As I mentioned in my previous article highlighting topics discussed at the 2017 ADSA meetings, pain management during disbudding and dehorning was suggested by Dr. Ruegg to be the next market access issue for the dairy industry.
On the topic of robotic milking, we presented results of a study at the University of Minnesota comparing milking frequency of heifers and older cows in 32 farms with free flow Lely robotic milking systems. Daily, individual cow data were collected from the robot software for 18 months. We found that heifers on average, across farms, were milked approximately 2.4 times per day during the first 4 weeks in lactation compared to older cows being milked about 3.2 times per day. Late in lactation (>240 DIM) heifers were milked more often than older cows. This might indicate that heifers are lagging behind older cows in early lactation. Is this a result of competition with older cows or inadequately training heifers to use the robot? More research is needed to answer this question.
A study from the University of Guelph showed that acute transition cow health disorders such as retained placenta, displaced abomasum and mastitis, were associated with changes in daily milk production and rumination time from three to six days before diagnosis in herds with robotic milking systems in Canada. Subclinical ketosis and endometritis resulted in longer term changes in productivity and behavior. Another study from the University of Guelph suggested that there might be potential to use feed tables in robotic milking systems to reduce negative energy balance and subclinical ketosis by accounting for milk production of fresh cows.