Abstract:

This dataset is derived from an experiment to determine olfactory acuity of control and oil exposed late juvenile and early adult mahi-mahi using an electro-olfactogram (EOG) technique.

Suggested Citation:

Schlenker, L.. 2019. Control and oil-exposed juvenile mahi-mahi (Coryphaena hippurus) electro-olfactogram data. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-jhhx-4k44

Publications:

Schlenker, L. S., Welch, M. J., Mager, E. M., Stieglitz, J. D., Benetti, D. D., Munday, P. L., & Grosell, M. (2019). Exposure to Crude Oil from the Deepwater Horizon Oil Spill Impairs Oil Avoidance Behavior without Affecting Olfactory Physiology in Juvenile Mahi-Mahi (Coryphaena hippurus). Environmental Science & Technology, 53(23), 14001–14009. doi:10.1021/acs.est.9b05240

Purpose:

This dataset is derived from an experiment to determine olfactory acuity of control and oil exposed juvenile mahi-mahi (Coryphaena hippurus) using an electro-olfactogram (EOG) technique to measures the voltage change across the olfactory epithelium.

Data Parameters and Units:

The dataset consists of 3 excel files describing water chemistry, fish biometric data, and initial and final sum 50 PAH data. Dataset also consists of EOG and filtered EOG in several text files. Initial and final sum 50 PAH data from 6% 24-hr HEWAF exposures (MAHI EOG PAH DATA.csv); mahi-mahi lengths, masses, treatment group, and fish ID number (Mahi EOG Data.csv); voltage change across the olfactory epithelium of control and oil exposed bicolor damselfish while various olfactory cues were delivered (Labchart .txt files; e.g., file mahi 11_25_18.txt is EOG recordings from several mahi-mahi on November 25, 2018)

Methods:

Initial and final sum 50 PAH data from 6% 24-hr HEWAF exposures (MAHI EOG PAH DATA.csv); mahi-mahi lengths, masses, treatment group, and fish ID number (Mahi EOG Data.csv); voltage change across the olfactory epithelium of control and oil exposed mahi-mahi while various olfactory cues were delivered (Labchart .txt files; e.g., file mahi 11_25_18.txt is EOG recordings from several mahi-mahi on November 25, 2018). Consult Mahi EOG Data.csv for fish numbers that were used in analysis. Fish numbers that are present on Labchart .txt files, but do not appear on the Mahi EOG Data.csv file are fish that were not used in analysis because reliable recordings were never established. All mahi-mahi were 33-50 days post hatch and were raised at the University of Miami Experimental Hatchery from wild-caught parents. MAHI EOG PAH DATA.csv: PAH Data represents the sum PAH concentration (micrograms per liter) of 50 listed PAHs as part of a static 24-hr treatment. Initial and final samples were collected for each 24-hr incubation. All oil treatments were a 6% HEWAF. Sum % refers to the percent of a particular ring class (e.g. 2-ring, 3-ring, 4-ring, and >4-ring). LABCHART TEXT FILES: Labchart text files need to be imported into Labchart (AD Instruments) to be used. File names include the date of recording (e.g. file Mahi 11_25_18.txt is EOG recordings from several juvenile mahi-mahi on November 25, 2018) which can be matched to fish information (Mahi EOG Data.csv), PAH exposure information (MAHI EOG PAH DATA.csv), and water chemistry information (Mahi EOG Water Chem Data.csv). Two-channels were used for recording, EOG and Filtered EOG. Filtered EOG had a 60hz filter and was used for all measurements and analysis. Electro-olfactogram (EOG) experiments were performed to directly quantify the ability of control (n=12) and oil-exposed (n=12) juvenile mahi-mahi to a WAF of crude oil as an olfactory cue at the olfactory epithelium (OE). Additional olfactory cues were also tested. These experiments were done blinded, so the researcher did not know whether the fish were oil exposed or control at the time of experiment. All EOG experiments were done in clean seawater. Not all fish included in the Labchart files provided robust data. See the Mahi EOG Data.csv to see which fish were used. Mahi-mahi were anesthetized with 0.2 g/L MS-222 (tricaine methanesulfonate, Western Chemical, Inc., Ferndale, WA), buffered with NaHCO3 (Sigma Aldrich, St. Louis, MO), and transferred to the submerged experimental chamber where they were ventilated with aerated culture water containing 0.1 g/L MS-222. To access the olfactory epithelium the septum that separates the anterior and posterior nares was removed and a recording electrode, a non-polarizable Ag-AgCl electrode (Warner Instruments, Hamden, CT), fitted with a 1.5 mm glass capillary tube (Warner Instruments) pulled to a fine tip and filled with 3 M potassium chloride (Sigma Aldrich) was placed on the longest lamellae of the anterior dorsal section of the OE. An identical reference electrode was placed directly posterior to the eye. All recordings were performed blind such that the researcher did not know whether the fish was a control or oil exposed individual. The output from the recording and reference electrode was differentially amplified 1000x (DP-311, Warner Instruments), filtered (0.1Hz-0.1kHz, 50/60Hz; DP-311, Warner Instruments), digitized and filtered (60 Hz, Power Lab, AD Instruments, Dunedin, NZ), and recorded (Chart Software v. 8.1.3, AD Instruments, Colorado Springs, CO). All cues were delivered in a randomized order with each cue delivered three times and a blank cue was administered three times within the randomized olfactory cues. Cue abbreviations are as follows: food=food pellet rinse, food.1=10% dilution of food pellet rinse rinse, oil/5xHEWAF=WAF of crude oil cue, ala-2=10-2 M l-alanine, ala-3=10-3 M l-alanine, tca-3=10-3 M taurocholic acid, blank=control seawater. The food pellet extract was made by soaking 5.4 g of Otohime C2 pellets in 800 mL of seawater for 12 hours and filtering it through 100 m mesh. This batch of pellet que was frozen in 10 mL aliquots at -20C and each aliquot was further diluted with an additional 40 mL of seawater upon thawing to make the pellet cue. For the oil cue a full strength HEWAF was made as described previously with the exception that 5 g of oil was blended with 1 L of seawater and this 100% HEWAF was used full strength as a cue. Mahi EOG Data.csv: Mahi EOG Data.csv data includes lengths and masses of experimental mahi-mahi and treatment (oil or control). This dataset only includes data from fish that were included in analysis. If a particular fish is present in the Labchart files but not included in Mahi EOG Data.csv it was excluded from analysis because reliable recordings were not established. Fish ID corresponds to comments in Labchart files.

Instruments:

A non-polarizable Ag-AgCl electrode (Warner Instruments, Hamden, CT), fitted with a 1.5 mm glass capillary tube (Warner Instruments) pulled to a fine tip and filled with 3 M potassium chloride (Sigma Aldrich) was placed on the longest lamellae of the anterior dorsal section of the olfactory epithelium. The output from the recording and reference electrode was differentially amplified 1000x (DP-311, Warner Instruments), filtered (0.1Hz-0.1kHz, 50/60Hz; DP-311, Warner Instruments), digitized and filtered (60 Hz, Power Lab, AD Instruments, Dunedin, NZ), and recorded (Chart Software v. 8.1.3, AD Instruments, Colorado Springs, CO).

Individual Files: