Wosnick Natascha, Chaves Ana Paula, Niella Yuri Vieira, Takatsuka Veronica, Hazin Fábio Hissa Vieira, Nunes Jorge Luiz Silva, Morick Danny
Programa de Pós-graduação em Zoologia, Universidade Federal do Paraná, Curitiba 81530-000, Brazil.
Laboratório de Organismos Aquáticos, Universidade Federal do Maranhão, São Luís 65080-805, Brazil.
Animals (Basel). 2020 Nov 4;10(11):2030. doi: 10.3390/ani10112030.
Physiological adaptations have evolved to help sharks face rapid periods of feast. Tiger sharks are generalist apex predators that rely on a high-lipid/protein diet. To achieve a satisfactory nutritional condition, proper lipid absorption and hepatic storage are needed. Bile secretion in sharks is low and sporadic but increases during short periods of fasting. The present study describes a physiological impairment caused by bile accumulation in juvenile tiger sharks, possibly due to prolonged fasting. These evidences suggest that, even though sharks have adaptations that prevent them from dying from starvation, alarming physiological alterations might occur. Future studies are needed to assess how such a condition can affect wild populations, as well as possible sublethal consequences that could impact their long-term survival.
生理适应性的进化有助于鲨鱼应对快速的丰食期。虎鲨是依赖高脂/高蛋白饮食的广食性顶级掠食者。为达到令人满意的营养状况，需要适当的脂质吸收和肝脏储存。鲨鱼的胆汁分泌量少且不连续，但在短期禁食期间会增加。本研究描述了幼年虎鲨因胆汁积累可能导致的生理损伤，这可能是由于长期禁食所致。这些证据表明，尽管鲨鱼具有防止它们饿死的适应性，但仍可能发生令人担忧的生理变化。未来需要开展研究，以评估这种状况如何影响野生种群，以及可能影响其长期生存的潜在亚致死后果。
