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Machine milking-induced alterations of teat tissue may impair local defense mechanisms and increase the risk of new intramammary infections. The objective of the current study was to assess the influence of short-term and long-term alterations of teat tissue and infectious status of the udder quarter on the risk of naturally occurring new intramammary infections, inflammatory responses, and mastitis. Short-term and long-term changes in teat condition of right udder quarters of 135 cows of a commercial dairy farm in Saxony-Anhalt, Germany, were recorded monthly for 10 mo using simple classification schemes. Quarter milk samples were collected from all examined quarters at each farm visit. Bacteriological culture results and somatic cell counts of quarter milk samples were used to determine new inflammatory responses (increase from ≤100,000 cells/mL to >100,000 cells/mL between 2 samples), new infections (detection of a pathogen from a quarter that was free of the same pathogen at the preceding sampling), and new mastitis (combination of new inflammatory response and new infection). Separate Poisson mixed models for new inflammatory responses, new infections, and new mastitis caused by specific pathogens or groups of pathogens (contagious, environmental, major, minor, or any) were used to estimate risk ratios and 95% confidence intervals. Data preparation and parameter estimation were performed using the open source statistical analysis software R. We observed no effect of any variable describing teat condition on the risk of new intramammary infections, inflammatory responses, or mastitis. Intramammary infections of the same udder quarter in the preceding month did not affect risk either.

The aim of this study was to determine if raw milk cheese or cheese to be made out of heated milk, manufactured in small German cheese dairies might be a reservoir of contaminations with methicillin-resistant Staphylococcus aureus (MRSA). Due to predominantly manual handling during cheese making, recontaminations with Staphylococcus (S.) aureus or MRSA cannot be excluded. Commercial cheese products (n = 72) available in the region of Hanover (Lower Saxony) and dairy products offered via internet were analyzed with regard to the occurrence of S. aureus and MRSA. Thereof, two cheese samples, manufactured from pasteurized milk and two samples, produced from raw milk, were S. aureus positive with CFU/g between 1.0 × 10 1 and 7.0 × 10 1. MRSA was not detected. All analysed cheese samples could be considered safe for consuming.

This field study focused on the possible effects of increased milking frequency (milking four times a day in comparison with milking twice a day) on clinical and bacteriological cure rates of clinical, antibiotically treated mastitis cases. Parameters tested were clinical, microbiological and full (cytomicrobiological) cure as well as the development of milk yield after the clinical mastitis episode. Cows from a large dairy herd meeting the study criteria (n=93) were assigned to two treatment groups by a systematic randomization scheme (blocked by body temperature <=or >39.5 degrees C). Both groups were randomly divided by experimental treatments: a) antibiotic intramammary treatment and milking 2-times a day; b) antibiotic intramammary treatment and milking 4-times a day. Treatments were initiated before the culture results were known. Cows were surveyed and evaluated on days 1-6, 24 and 31. No significant differences between treatment and control groups regarding clinical cure, microbiological cure, full cure and milk production could be established. Applying a 4-times a day milking regime did not lead to any significant effect, either positive or negative. Therefore, the results suggest that milking 4-times a day as a supporting therapy for mild, moderate and severe antimicrobially treated mastitis cases cannot be recommended.