Maternal effects and early-life performance are associated with parasite resistance across life in free-living Soay sheep

• Published in: Parasitology 2010-07, Vol.137 (8), p.1261-1273
• Main Authors: HAYWARD, A. D., PILKINGTON, J. G., PEMBERTON, J. M., KRUUK, L. E. B.
• Format: Article
• Language: English
• Subjects: Animals; Animals, Wild - genetics; Animals, Wild - parasitology; Animals, Wild - physiology; Biological and medical sciences; early-life performance; faecal egg counts; Feces - parasitology; Female; Fundamental and applied biological sciences. Psychology; General aspects; General aspects and techniques. Study of several systematic groups. Models; Invertebrates; Litter Size - physiology; Male; Mammalia; maternal effects; Offspring; Parasite Egg Count; Parasite resistance; Parasites - isolation & purification; Parasites - pathogenicity; Parasitic Diseases, Animal - immunology; Parasitic Diseases, Animal - parasitology; Phenotype; Pregnancy; Sheep - genetics; Sheep - parasitology; Sheep - physiology; Sheep Diseases - immunology; Sheep Diseases - parasitology; Soay sheep; strongyles; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution
• ISSN: 0031-1820; 1469-8161
• DOI: 10.1017/S0031182010000193

Maternal effects occur when the maternal phenotype influences that of the offspring in addition to the effects of maternal genes, and may have a considerable influence on offspring parasite resistance. These effects, and the effects of early levels of reproduction and parasite resistance, may persist into later life and even influence ageing rates. Here we analyse a 20-year longitudinal data set collected on a free-living population of Soay sheep, to investigate the associations between a suite of maternal phenotypic traits and early-life performance on measures of parasite resistance across life. Our results show that maternal effects are important in determining offspring parasite resistance, since lambs born as twins and those born to the youngest and oldest mothers show higher parasite burdens. We show that the association between parasite resistance and natal litter size persists into adulthood. We also show that age-specific changes in parasite resistance in males are associated with natal litter size, and that age-specific changes in females are influenced by early-life levels of reproduction and parasite infection. These results add to the growing evidence that conditions experienced by individuals during development can have a profound influence on immediate and late-life performance and may even influence ageing.