Die Eignung der Leitfähigkeitsmessung zur Eutergesundheitsüberwachung bei Milchschafen

Summary

Sheep milk production is not very common in Germany. Only 10,000 sheep are used for milking. However, a considerable number of farmers work according to the stan-dards of organic farming. Only farm dairies process the milk and sell the products directly to the consumer. Thus, the quality of the raw milk has to be high although the EU regulations for sheep milk are not as strict as for cow’s milk. Animal recording is not a standard in dairy sheep production and farmers lack the information which might be gained by this monthly monitoring of each animal. Animal side tests are necessary and the aim of our study was to investigate the usability of conductivity measurement as an indicator of sub clinical mastitis in ewes. Data were collected from 164 ewes in six organic dairy sheep farms. At first, electrical conductivity (EC) of foremilk was measured to avoid the influence of alveolar milk ejection. Afterwards samples for cyto-bacteriological analyses were gained aseptically. 318 samples could be used for statistical analysis. Prevalence of sub clinical mastitis was low. Only 5.3% of all sam-ples showed a somatic cell count over 100,000 cells per ml in combination with a positive result of the bacteriological investigation. The important pathogens were coagulase-negative staphylococci (79.1% of all positive tested samples). Mean EC was low, but differed significantly between the group of udder halves with normal secretion and with mastitis: 4.9 and 5.5 mS/cm, respectively. The calculation of EC differences between the halves of each udder leaded to the same result: healthy halves had a mean difference of 0.1 mS/cm; 0.4 mS/cm was the difference between healthy and mastitic halves. Nevertheless, the EC difference was to low to use it as an indicator alone. EC measurement can be used to monitor udder health in dairy sheep, but should be carried out on a regular base to achieve reliable results.