To put before farmers the risks and benefits of particular aspects of cow management and encourage them to make decisions about change appears to be the modern approach. Advice comes from many directions and increasingly professional advisors are engaged, including the vet. Case histories are brought forward to enthuse about particular approaches and the findings of research are proffered to support technical developments. Over this winter and for the foreseeable future, it appears that many aspects of cow care are being related to antibiotic usage and the benefits of reducing volumes by better feeding, fertility, immune response, housing, milking technique, staff training and a wide range of activities and directives. It seems that by mentioning antibiotics, farmers will listen to whatever message follows.
The benefits and drawbacks of block calving
It was interesting to attend an on-farm session on autumn block calving presented by AHDB Dairy. In block calving, all cows calve within a twelve-week period. To achieve this, there must be a strong motivation because the management of the herd has to undergo a different mind-set to all-year-round milk production. There are issues about milk price contracts and the demands from purchasers for even milk intake, and the farmer is committing to long-term change, but beneficial changes appear to be due to intensification of activities.
On the farm visited, the management of the baby calves had been left to one person and there had been difficulties with healthy rearing and a higher than desired pneumonia count. With block calving, too many calves are born each day for one person to manage, so the whole colostrum uptake and rearing regime becomes more “professional”. By Christmas, baby calf management is over and this intensification of effort has yielded more healthy calves, better growth and conception rates and more heifers entering the herd either as replacements or for herd expansion. Of great importance was the view that calf rearing was now a job well done.
The farm had to consider carefully the availability of tracks. Access for the cows onto the pasture takes place approximately six weeks earlier (February/March). Cow tracks that are not used by tractors enable the cows to walk into the fields with less impact on gateways and walking through mud. Infrastructure had been put in to enable earlier and longer grazing periods with water troughs in the middle of the fields. With the cows dry in the summer months (July/August), attention is paid to the grazing paddocks and achieving two or three cuts of silage.
The farmer was asked what motivated him to start the process of breeding and management to achieve block calving. “So that we could get some time off during the summer,” was the reply.
The Vital 90
Throughout February, Elanco arranged a series of discussion meetings for veterinary surgeons and their clients to consider the value of concentrating knowledge and effort on the 60 days before calving and 30 days afterwards (“The Vital 90”). Dr Christian Scherpenzel (GD Animal Health Holland) outlined the relevance of developments in gene research to everyday mastitis. The speaker summarised the findings as showing a “zoo of bugs in the udder”.
A healthy quarter yields 7,000 bacterial sequences. Where there is a clinical infection, the dominant strain reduces the presence of other species, but treating with antibiotics has not been shown to reduce the volume of commensals. Clearly, a much deeper understanding of infection and therapy will follow as the technology is applied.
The anti-inflammatory response of the cow during pregnancy and the dry period was highlighted by the speaker. In the third trimester of pregnancy there is a stronger antiinflammatory response to protect the new born calf. Lactoferrin inhibition of bacteria has been identified for many years but this is lower in high yielding cows. Emphasis is placed on the drying-off technique and it was clear from the discussion that there are different approaches in individual herds and for individual cows. Feeding and energy levels can increase immunity and improve the immune response to infection in the udder.
Veterinary surgeons are urged to discuss drying-off technique in detail with clients. AHDB Dairy and University of Nottingham have produced videos and fact sheets to aid implementation of best practice. Cows bred for quick milk release have a higher susceptibility to mastitis infections, with 60 percent of cows recorded with open teat canals two weeks after drying off. The speaker advises that the use of a teat sealant only at drying off needs to be combined with hygienic dry cow housing. Because the cow has a higher susceptibility to intramammary infections in late gestation, management to improve the pro-inflammatory response is likely to be beneficial.
Mike Overton has moved to Elanco following research at the universities of California and Georgia. Highlighting the risks, costs and opportunities with transition management, he noted that healthier transition cows yield greater profit for the farmer. Studies have shown a wide variation in the recorded incidence of disease between herds. The speaker emphasised that the accurate recording of disease is critical for understanding the impact of disease on a herd and for improving herd management. Different people define and record disease differently. The true impact of disease is underestimated due to the poor quality of recording.
Rewarding disease detection
There are essential aspects to be developed between the veterinary advisor and the farmer client. It is important to agree what is being detected and recorded with treatment decisions and standardised protocols. The veterinary surgeon needs to pay attention to records and provide feedback to the farmer and the farm staff. It is important to show value to the farmer of him taking the trouble to record. The cost of veterinary time to do this is low with the effort mainly coming from the farmer, but the up-front effort to have effective systems yields long-term benefits. One of the factors to be addressed early on is that better recording leads to higher levels of disease recognised within the herd. It is necessary to reward staff for better working practices. The initial rise in disease should fall with earlier treatments and disease prevention management.
There were gems of information that came out during discussion. Having emphasised the subsequent impact on immune dysfunction from a negative nutritional balance with transition cows, the speaker advised that cows should not be moved within 10 days of calving. It would have been useful to establish the practice on different farms and whether individuals are moved to calving accommodation during the risk period. This was just one of many aspects that will need to be discussed between the vets and their clients on the way home.
