Hydration-induced modulation of feeding responsiveness in terrestrial slugs

✍ Scribed by Prior, David J.

• Book ID: 102890352
• Publisher: John Wiley and Sons
• Year: 1983
• Tongue: English
• Weight: 680 KB
• Volume: 227
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402270104

✦ Synopsis

In various species of animals the level of body hydration is known to affect feeding responsiveness. In order to understand the mechanisms that underlie this form of behavioral modulation, hydration-induced changes in feeding have been examined in the terrestrial slugs L i m a pseudoflaws and Lehmannia ualentiana. Air-dehydration of slugs to 70-60% of initial body weight (%IBW) abolishes feeding. Feeding responsiveness is rapidly restored in these slugs after they are allowed to rehydrate in contact with a moist surface. Injections of hyperosmotic mannitol or sucrose solution also result in abolition of feeding, thus suggesting that hemolymph osmotic pressure is involved in modulation of the feeding response. Correspondingly, if mannitol-injected or air-dehydrated slugs are injected with 0.1 x saline, feeding is restored in a manner similar to that observed following contact-rehydration. Feeding was restored, however, only in those slugs whose hemolymph was diluted to at least 180-190 mOsm/kg H 2 0 , which is the hemolymph osmolality of slugs at 75-70% IBW. The present results are consistent with the hypothesis that hydration modulation of feeding in slugs is mediated by hemolymph osmotic pressure.