Morphology of heart and vessels of the cardiac base in Magellanic penguin (Spheniscus magellanicus)

ABSTRACT Magellanic penguin is medium-sized seabird originated from southern hemisphere with colonies near Patagonia. At certain times of the year in Brazilian coast, a few penguins lose their hunting routes and can´t return because they are very sick. Thirty-four penguins died in Espírito Santo´s coast. This study analyzed the cardiac morphology and morph metric of heart chambers and walls, valves, and arteries of the cardiac base. These parts were analysed and stained by Hematoxilin and eosin and Gomori´s trichrome. Mainly targeting the collagen´s composition in each described part the Picru-sirius Red´s stain under polarized light was used. Among thirty-four penguin hearts, none presented discrepancy in morphology, they were all very similar. The characterization of collagen by Picrusirius Red stain highlighted type 1 collagen in comparison to type 3 collagen in most structures, giving a more reddish appearance in almost of them. In conclusion, the cardiac anatomy of the Magellanic Penguin is similar to that of other birds, with a predominance of type I collagen.

摘要：麦哲伦企鹅（Magellanic Penguin）是起源于南半球的中型海鸟，其自然种群多栖息于巴塔哥尼亚附近海域。每年特定时段，巴西沿海会有少量麦哲伦企鹅因罹患重症而迷失捕猎航线，无法返回栖息地，本研究的样本为在圣埃斯皮里图州沿海死亡的34只该种企鹅。本研究对麦哲伦企鹅的心脏形态，以及心腔、心肌壁、瓣膜与心基部动脉的形态测量参数展开分析。所有组织样本均通过苏木精-伊红（Hematoxylin and Eosin）染色与戈莫里三色染色（Gomori's Trichrome Staining）进行处理与染色；为重点探究各目标结构的胶原蛋白组成，本研究采用偏振光下的苦味酸-天狼星红（Picrosirius Red）染色法。34份企鹅心脏样本的心脏形态均无显著差异，整体结构高度一致。通过苦味酸-天狼星红染色对胶原蛋白进行表征后发现，多数心脏结构中I型胶原蛋白（type 1 collagen）的占比高于III型胶原蛋白（type 3 collagen），样本整体呈现偏红的染色结果。综上，麦哲伦企鹅的心脏解剖结构与其他鸟类相似，且以I型胶原蛋白为主导。