Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico.
Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, Mexico.
PLoS One. 2023 Sep 29;18(9):e0287097. doi: 10.1371/journal.pone.0287097. eCollection 2023.
Many digenean trematodes require three hosts to complete their life cycle. For Cymatocarpus solearis (Brachycoeliidae), the first intermediate host is unknown; the Caribbean spiny lobster Panulirus argus is a second intermediate host, and the loggerhead turtle Caretta caretta, a lobster predator, is the definitive host. Trophically-transmitted parasites may alter the behavior or general condition of intermediate hosts in ways that increase the hosts' rates of consumption by definitive hosts. Here, we examined the effects of infection by C. solearis on P. argus by comparing several physiological and behavioral variables among uninfected lobsters (0 cysts) and lobsters with light (1-10 cysts), moderate (11-30 cysts), and heavy (>30 cysts) infections. Physiological variables were hepatosomatic index, growth rate, hemocyte count, concentration in hemolymph of cholesterol, protein, albumin, glucose, dopamine (DA) and serotonin (5-HT). Behavioral variables included seven components of the escape response (delay to escape, duration of swimming bout, distance traveled in a swimming bout, swim velocity, acceleration, force exerted, and work performed while swimming). There was no relationship between lobster size or sex and number of cysts. Significant differences among the four lobster groups occurred only in concentration of glucose (lower in heavily infected lobsters) and 5-HT (higher in heavily and moderately infected lobsters) in plasma. As changes in 5-HT concentration can modify the host's activity patterns or choice of microhabitat, our results suggest that infection with C. solearis may alter the behavior of spiny lobsters, potentially increasing the likelihood of trophic transmission of the parasite to the definitive host.
许多复殖吸虫需要三个宿主才能完成其生命周期。对于拟角贝科的 C. solearis，第一个中间宿主未知；加勒比刺龙虾 Panulirus argus 是第二个中间宿主，而作为捕食者的红海龟 Caretta caretta 是最终宿主。营养传播的寄生虫可能会以增加中间宿主被最终宿主捕食的速度的方式改变中间宿主的行为或一般状况。在这里，我们通过比较未感染的龙虾（0 个囊蚴）和轻度（1-10 个囊蚴）、中度（11-30 个囊蚴）和重度（>30 个囊蚴）感染的龙虾的几种生理和行为变量来检查 C. solearis 感染对 P. argus 的影响。生理变量包括肝体比、生长率、血球计数、血淋巴中胆固醇、蛋白质、白蛋白、葡萄糖、多巴胺 (DA) 和血清素 (5-HT) 的浓度。行为变量包括逃避反应的七个组成部分（逃避延迟、游泳回合持续时间、游泳回合中移动的距离、游泳速度、加速度、施加的力以及游泳时所做的功）。龙虾的大小或性别与囊蚴数量之间没有关系。仅在四个龙虾组之间发生了显著差异，仅在血浆中葡萄糖（重度感染的龙虾中较低）和 5-HT（重度和中度感染的龙虾中较高）的浓度上。由于 5-HT 浓度的变化可以改变宿主的活动模式或微生境选择，我们的结果表明，C. solearis 的感染可能会改变刺龙虾的行为，从而增加寄生虫向最终宿主营养传播的可能性。
