[Udder infections with coagulase-negative staphylococci in freshly calved heifers]. / Uierinfecties met coagulase negatieve stafylococcen (CNS) bij nieuwmelkte vaarzen.

To determine the prevalence of udder infections in fresh calved heifers all quarters of 98 heifers on eleven commercial farms were sampled weekly during the first eight weeks of lactation. The samples during the first four weeks of this period were used for bacteriological examination and in all samples a somatic cell count was made. The prevalence of S. aureus after calving in these heifers was 12.5%. Coagulase-negative staphylococci (CNS) were isolated from half of the heifers. The predominant coagulase-negative staphylococcus species were S. xylosis and S. hyicus. The CNS, with exception of S. hyicus, had a very small effect on the cell count.

[Pasteurella haemolytica serotypes in cattle]. / Pasteurella haemolytica serotypen bij runderen.

Eight-two bovine Pasteurella haemolytica strains were serotyped. The majority of the strains were isolated from calves which had died from fibrinous pneumonia and small numbers from cases of pleuritis, sepsis and abortion. A total of eight different serotypes were noticed. Serotype A1 was found to be the most prevalent 37.8 per cent, followed by serotype A2 with 20.7 per cent. Antibiotic resistance was found for sulfonamide, tetracycline and penicillin in about half of all strains. Conventional combination of biotype to serotype per strain was not confirmed by the results of arabinose and trehalose fermentation.