[Mastitis in sheep in the Netherlands]

Little is known of udder health in sheep in the Netherlands. The present study represents an effort to gain some insight into this matter. For this purpose, test samples were taken during the period from March 6, 1981 to April 17, 1981, on sixteen commercial farms in the province of Gelderland, on which there were a total number of 936 nursing ewes; this was done again during the period from June 22, 1981 to June 25, 1981, final sampling being done during April 1982, though this was confined to animals showing poor udder health in the year before. Cell counts were made by an adjusted method using the Coulter Counter. The cell counts recorded were higher than those reported in the literature. Of the samples examined, from 20 to 25 per cent contained more than 2,000,000 cells per ml. Cell counts were high during the early period of lactation, subsequently diminished and then increased again about the time of weaning. Moreover, cell counts increased with age and possibly, though not significantly so, with the number of suckling lambs. Bacteriological examination shortly after lambing was positive in 7.3 per cent of the ewes and 4.1 per cent of samples of udder halves.