Structural cutaneous adaptations for defense in toad (Rhinella icterica) parotoid macroglands
| Autor: | Carlos Jared, Edmund D. Brodie, Simone G.S. Jared, Maria Cecília Fleury-Curado, Marta M. Antoniazzi, Eduardo Regis-Alves, Beatriz Maurício, Pedro Luiz Mailho-Fontana |
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| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
0301 basic medicine biology Toad Anatomy Toxicology biology.organism_classification 010603 evolutionary biology 01 natural sciences Bufonidae Rhinella icterica 03 medical and health sciences Dogs Exocrine Glands 030104 developmental biology Predatory Behavior biology.animal Dorsal region Amphibian Venoms Animals |
| Zdroj: | Toxicon. 137:128-134 |
| ISSN: | 0041-0101 |
| DOI: | 10.1016/j.toxicon.2017.07.022 |
| Popis: | Toads have a pair of glandular accumulations on each side of the dorsal region of the head known as parotoid macroglands. These macroglands consist of secretory units (granular glands), each one capped with an epithelial plug. When threatened, toads point one of the parotoids toward the aggressor, and if the aggressor squeezes the parotoid with its teeth, jets of poison will come out of the secretory units and hit the predator's oral mucosa, thereby causing poisoning. Our study focused on the mechanism of parotoid function by comparing parotoids from toads naturally attacked by dogs with those manually compressed. We verified that the process of glandular emptying in response to dog bites is very similar to that following manual compression. We observed that the structure of the plug plays an essential role in the release of the poison jets. Our results suggest that the parotoids may act as "bulletproof vests," reducing the impact of the force exerted by predator attacks, and thus may function as a passive antipredator mechanism. |
| Databáze: | OpenAIRE |
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