Problem robaczyc żołądkowo-jelitowych u jałówek w przemysłowej technologii chowu

The levels of infection with gastro-intestinal nematodes were compared in heifers of various technological groups. The highest inddence and intensity (EPG) were found in the oldest age-group (2-year-old). Mean values of the highest infectionin seasonal dynamics occured in May and August.The infection of the Nilverm treated heifers, used for mating and of those used for breeding, was lower than that of the untreated ones.The average final body-weight gain of pregnant heifers after treatment was by 24.3 kg (4.6%) higher compared with that of the untreated heifers.The average final body-weight gain of heifers in production cycle after treatment was by 7.6 kg (1.6%) higher compared with that of the untreated heifers. The heifers after treatment were used for mating 18 days earlier than untreated ones.