Paper on the effects of the Dutch mastitis control programme

One of my ideas for this blog is to make an entry including the main results of scientific papers that we have published. Well, I am a little behind schedule. But here is a paper that was published last February. So for some of you, this post does not add much value I am afraid. On the other hand, not everybody is following the scientific literature so who knows it is interesting.

Last year, Theo Lam, projectleader of the Dutch 5-year mastitis control project and director of UGCN (the organization that was instituted just to carry out much of the work within that project) had the idea to write a paper on the changes in udder health in the Netherlands during the 5-year mastitis control project. This paper was published in the Journal of Dairy Science last February. Before the programme started, a "zero-measurement" was done, to see what the udder health status was in the Netherlands, in terms of incidence of clinical mastitis, somatic cell count as well as knowledge and attitude (mindset) of the farmers. Five years later these measurements were repeated. The difference between both measurements can be attributed to the mastitis control programme. Basic conclusions were that the indicence of clinical mastitis decreased significantly with 5.4 %. There was no significant difference in somatic cell counts. Also the mindset of farmers towards udder health did change during the programme time. The data were used for a normative economic study, which showed that, on the national level, the total failure costs (milk production losses, culling, treatment and veterinary costs) due to mastitis decreased with € 8 million per year.

However, this sounds OK, but there is one major problem: there is no control group. We do not know how the status of Dutch dairy farmers would be when the 5-year control programme would not have been there. So we have to be a bit careful when interpreting these figures. The full abstract of this paper is given below.

Because of increasing bulk milk somatic cell counts and continuous clinical mastitis problems in a substantial number of herds, a national mastitis control program was started in 2005 to improve udder health in the Netherlands. The program started with founding the Dutch Udder Health Centre (UGCN), which had the task to coordinate the program. The program consisted of 2 parts: a research part and a knowledge-transfer part, which were integrated as much as possible. The knowledge-transfer part comprised 2 communication strategies: a central and a peripheral approach. The central approach was based on educating farmers using comprehensive science-based and rational argumentation about mastitis prevention and included on-farm study group meetings. Comprehensive education materials were developed for farmers that were internally motivated to improve udder health. In the peripheral approach it was tried to motivate farmers to implement certain management measures using nontechnical arguments. Mass media campaigns were used that focused on one single aspect of mastitis prevention. These communication strategies, as well as an integrated approach between various stakeholders and different scientific disciplines were used to reach as many farmers as possible. It should be noted that, because this intervention took place at a national level, no control group was available, as it would be impossible to isolate farmers from all forms of communication for 5 years. Based on several studies executed during and after the program, however, the results suggest that udder health seemed to have improved on a national level during the course of the program from 2005 to 2010. Within a cohort of dairy herds monitored during the program, the prevalence of subclinical mastitis did not change significantly (23.0 in 2004 vs. 22.2 in 2009). The incidence rate of clinical mastitis, however, decreased significantly, from 33.5 to 28.1 quarter cases per 100 cow years at risk. The most important elements of the farmers' mindset toward mastitis control also changed favorably. The simulated costs of mastitis per farm were reduced compared with a situation in which the mastitis would not have changed, with € 400 per year. When this amount is extrapolated to all Dutch farms, the sector as a whole reduced the total costs of mastitis by € 8 million per year. It is difficult to assign the improved udder health completely to the efforts of the program due to the lack of a control group. Nevertheless, investing € 8 million by the Dutch dairy industry in a 5-yr national mastitis control program likely improved udder health and seemed to pay for itself financially.