Encel Stella A, Simpson Emily K, Schaerf Timothy M, Ward Ashley J W
School of Life and Environmental Sciences, University of Sydney, Camperdown 2006, Australia.
R Soc Open Sci. 2023 Aug 9;10(8):230579. doi: 10.1098/rsos.230579. eCollection 2023 Aug.
Immunocompetence and reproduction are among the most important determinants of fitness. However, energetic and metabolic constraints create conflict between these two life-history traits. While many studies have explored the relationship between immune activity and reproductive fitness in birds and mammals inoculated with bacterial endotoxin, very few have focused on fish. Fish have been neglected in this area due, in part, to the claim that they are largely resistant to the immune effects of endotoxins. However, the present study suggests that they are susceptible to significant effects with respect to reproductive behaviour. Here, we examined the reproductive behaviour of male guppies following exposure to bacterial lipopolysaccharides (LPS) in comparison to that of male guppies in a control treatment. Additionally, we investigated the responses of females to these males. We show that although immune challenge does not suppress general activity in male guppies, it significantly reduces mating effort. While females showed no difference in general activity as a function of male treatments, they did exhibit reduced group cohesion in the presence of LPS-exposed males. We discuss this in the context of sickness behaviours, social avoidance of immune-challenged individuals and the effects of mounting an immune response on reproductive behaviour.
免疫能力和繁殖能力是健康状况的最重要决定因素。然而，能量和代谢限制在这两种生活史特征之间产生了冲突。虽然许多研究探讨了接种细菌内毒素的鸟类和哺乳动物的免疫活动与繁殖健康之间的关系，但很少有研究关注鱼类。鱼类在这一领域被忽视，部分原因是有人声称它们对内毒素的免疫作用具有很大的抵抗力。然而，本研究表明，它们在繁殖行为方面易受显著影响。在这里，我们将暴露于细菌脂多糖（LPS）后的雄性孔雀鱼的繁殖行为与对照处理中的雄性孔雀鱼的繁殖行为进行了比较。此外，我们研究了雌性对这些雄性的反应。我们发现，虽然免疫挑战不会抑制雄性孔雀鱼的一般活动，但它会显著降低交配努力。虽然雌性在一般活动方面没有因雄性处理而表现出差异，但在存在暴露于LPS的雄性的情况下，它们确实表现出群体凝聚力下降。我们在疾病行为、对免疫挑战个体的社会回避以及免疫反应对繁殖行为的影响的背景下讨论了这一点。
