TDK conference 2014

Nowadays mastitis has been identified as the most costly disease within the dairy industry. Economics of clinical mastitis have been subject to many recent studies. However, the subclinical form of mastitis has often been suspected to have a large influence on the revenue of a farm, but has been analysed rarely. The aims of this study were, to provide adequate information on the revenue loss of East-German dairy farms due to subclinical mastitis.

The data was taken from 12 farms in the Elbe-Elster region in the east of Germany. The number of dairy cows subjected to this study totalled 7,648. Their milk composition data were taken individually once a month, two to three times on the test day, according to the number of milking, in the period of June 2011 to June 2012. A fluorescent optical measurement via the Fossomatic was the test method. “Herde” which is a herd management program by Agrosoft, was used to analyse the data. The 100,000 cells/ml cut off value was used to identify subclinical udder inflammation in the survey.

The results of this study show that subclinical mastitis has an impact which causes a large milk yield depression. Even cows with a SCC more than 50,000 cells/ml, but below 100,000 cells/ml showed a remarkable milk production loss of over 8% which really underlines that inflammatory changes must be present in cows showing a SCC of more than 50,000 cells/ml. Cows that had an average SCC between 100,001-250,000 cells/ml showed a reduced milk production of over 15% even though this is still lower than the average SCC of 284,320 cells/ml. Average figures on an individual basis showed a daily decrease in milk production of 2.98 kg, 5.41 kg and 6.41 kg for a somatic cell count of 50.001-100,000 cells/ml, 100,001-250,000 cells/ml and over 250,001 cells/ml respectively.

According to the average milk price at the time a single cow, depending on the just mentioned SCC classification, showed a loss of € 294.85, € 536.80 and € 634.40 per lactation, respectively, in gross milk receipts. On an average herd level which was in case of this study 637 dairy cows, a total decrease of gross milk receipts of almost € 241,000.00 per year was estimated. Possible savings of feed costs were seen as fixed costs, as the lower milk production was not taken into account. The total loss of over € 273,000.00 was calculated taking premature disposal, discarded milk and reduced milk receipts into account. The findings show that the reduced milk receipts, due to lower milk production of cows with SCC higher than 50,000 cells/ml, had the highest influence of all the factors.