Immune challenge of mating effort: steroid hormone profile, dark ventral patch and parasite burden in relation to intrasexual competition in male Iberian red deer.

摘要: Testosterone secretion may regulate the reproductive effort and development of sexual traits, but it also involve costs at immunological metabolic levels. However, evidence for this trade-off in wild populations is scarce. Cortisol plays an important role mediating immune functions. In study, we analyzed whether endoparasite burden relates to hormonal levels (fecal testosterone cortisol metabolites) and/or morphological traits (size dark ventral patch, a trait that indicates males) male Iberian red deer. For purpose, sampled deer harvested during hunting actions 2 types south western Spain differed structure, affecting level male-male competition mates. We used coprological analyses estimate parasite mainly gastrointestinal bronchopulmonary nematodes protozoa, assessed metabolite from fecal pellets. found positive relationship host parasitation with both size these relationships depended on intensity population, being only under high-competition scenario. These results are discussed hypothesis immunocompetence handicap, suggesting cost level, and, therefore, higher susceptibility infection males make greater effort. effect seems be modulated by social environment (male-male competition) might lead different optima production development.