A waterborne chemical cue from Gulf toadfish, Opsanus beta, prompts pulsatile urea excretion in conspecifics

PHYSIOLOGY & BEHAVIOR

卷:171

Article

Fulton, Jeremy¹  LeMoine, Christophe M. R.^1,2  Bucking, Carol^1,3  Brix, Kevin V.⁴  Walsh, Patrick J.^1,4  McDonald, M. Danielle⁴ 

[1] Univ Ottawa, Dept Biol, Ottawa, ON K1N 6N5, Canada

[2] Brandon Univ, Dept Biol, Brandon, MB R7A 6A9, Canada

[3] York Univ, Dept Biol, Toronto, ON M3J 1P3, Canada

[4] Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Dept Marine Biol & Ecol, 4600 Rickenbacker Causeway, Miami, FL 33149 USA

关键词: Chemical communication;    Social/territorial signaling;    Ureotely;    Nitrogen excretion;    Urea;    Ammonia;    Serotonin;    Cortisol;   

DOI  :  10.1016/j.physbeh.2016.12.037

来源: Elsevier

【 摘 要 】

The Gulf toadfish (Opsanus beta) has a fully functional ornithine urea cycle (O-UC) that allows it to excrete nitrogenous waste in the form of urea. Interestingly, urea is excreted in a pulse across the gill that lasts 1-3 h and occurs once or twice a day. Both the stress hormone, cortisol, and the neurotransmitter, serotonin (5-HT) are involved in the control of pulsatile urea excretion. This and other evidence suggests that urea pulsing may be linked to toadfish social behavior. The hypothesis of the present study was that toadfish urea pulses can be triggered by waterborne chemical cues from conspecifics. Our findings indicate that exposure to seawater that held a donor conspecific for up to 48 h (pre-conditioned seawater; PC-SW) induced a urea pulse within 7 h in na ve conspecifics compared to a pulse latency of 20 h when exposed to seawater alone. Factors such as PC-SW intensity and donor body mass influenced the pulse latency response of na ve conspecifics. Fractionation and heat treatment of PC-SW to narrow possible signal candidates revealed that the active chemical was both water-soluble and heat stable. Fish exposed to urea, cortisol or 5-HT in seawater did not have a pulse latency that was significantly different than seawater alone; however, ammonia, perhaps in the form of NH4Cl, was found to be a factor in the pulse latency response of toadfish to PC-SW and could be one component of a multi-component cue used for chemical communication in toadfish. Further studies are needed to fully identify the chemical cue as well as determine its adaptive significance in this marine teleost fish. (C) 2016 Published by Elsevier Inc.

【 授权许可】

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