The effect of a national mastitis control program on the attitudes, knowledge, and behavior of farmers in the Netherlands.

Over the years, much effort has been put into implementing mastitis control programs in herds. To further improve utilization of such programs, there needs to be an understanding of the attitudes, knowledge, and behavior of farmers regarding udder health, and the way this can be influenced by mastitis control programs. This study aimed to explore the effect of a national mastitis control program on Dutch farmers' attitudes, knowledge, and behavior regarding mastitis. A total of 378 dairy farmers completed a survey on attitudes, knowledge, and behavior regarding mastitis before the start of a national mastitis control program in 2004, and 204 completed a similar survey in the final year of the program (2009). Although the average annual bulk milk somatic cell count (BMSCC) remained the same, the farmers' self-reported attitudes, knowledge, and behavior changed significantly. The problem level of BMSCC decreased from 285,000 cells/mL in 2004 to 271,000 cells/mL in 2009. More farmers perceived that they had sufficient knowledge about the prevention of mastitis (34% in 2004 vs. 53% in 2009) and they more often perceived that they knew the cause of a mastitis problem (25% in 2004 vs. 37% in 2009). The use of gloves for milking increased from 15 to 46%, the use of a standardized mastitis treatment protocol increased from 7 to 34%, and freestalls were cleaned more often (2.28 vs. 2.51 times/d) in 2009 compared with 2004. Most changes in attitudes, knowledge, and behavior did not differ between groups of dairy farmers whose herds had an initially low (≤ 162,000 cells/mL), medium (163,000 to 205,000 cells/mL), or high (>206,000 cells/mL) BMSCC. The high BMSCC group significantly decreased their annual BMSCC level by 15,000 cells/mL. Regression analysis showed that the decrease in BMSCC was associated with a change in farmers' perceptions (e.g., increased perceived knowledge about the effect of the milking machine on mastitis) and with a change in certain management practices (e.g., disinfecting all teats after milking). The results showed that a national mastitis control program affected the attitudes, knowledge, and behavior of farmers regarding mastitis and could contribute to udder health improvement in the long term.