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The association between faecal egg counts and serum IgG response against somatic (SAg) and two excretory/secretory antigens (ESAg-4h, ESAg-24h) obtained from adult Haemonchus contortus was monitored over one season in young Polish Wrzosowka ewes naturally infected with gastrointestinal nematodes. There was a considerable variation in faecal egg counts and in the proportion of larvae from each species recovered from faeces at different months. Very similar IgG responses against the three antigen preparations were observed; the differences among months were significant. The distribution of antibody among young ewes was unimodal and positively skewed. The repeatabilities of IgG responses against SAg and ESAg-24h were all positive and statistically significant, although repeatabilities against ESAg-4h were of border line significance. The correlation coefficients among IgG responses tended to increase in the second half of season. There was a significant association between increased IgG responses to somatic antigens and reduced faecal egg counts. The combination of antibody responses against different antigen preparations of H. contortus and faecal egg counts appear better at identifying resistant Polish Wrzosowka sheep than either method used in isolation.