codSDA: Oxygen uptake data from a juvenile Atlantic cod before and...

In denis-chabot/fishMO2: Calculate and Plot SMR, O2crit and SDA, and convert between oxygen units

Description

Oxygen uptake data from a juvenile (22.9 g) Atlantic cod (Gadus morhua) measured by intermittend-flow respirometry before and after ingestion of a meal (about 3.5% body mass, experimental diet). This is to illustrate calcSDA and plotSDA.

Format

A data frame with 947 observations on the following 5 variables:

DateTime

a POSIXct vector indicating date and time for each measurement

Logtime_hr

a numeric vector indicating the time, in hours, relative to feeding. Measurements obtained before feeding have a negative value for this variable

MO2

a numeric vector representing oxygen uptake, in micromoles of oxygen per min per kg of body mass

MO2cor

same as MO2, except for the first 10 hours after the meal: these measurements were corrected for the increase in MO2 resulting from the feeding procedure. The correction was based on an exponential decay function fitted to data obtained after a sham feeding that took place the day prior to feeding.

r2

a numeric vector representing the coefficient of determination R^2 of the regression between dissolved oxygen and time for a given value of MO2

Details

Intermittent flow respirometry and a 2.56 L respirometer were used to measure oxygen uptake in this juvenile cod (salinity of 27⋅6 ± 1⋅7, 11⋅8 ± 0⋅1∘ C, mean ± s.d.). The fish was fasted for 66 h before being placed into the respirometer to insure it was in post-absorptive state, a requirement to measure its standard metabolic rate. After 3 days, it was taken out of the respirometer, anasthetised, a tube was inserted in its stomach and water was flushed in its stomach (sham feeding). Approximately 24 h later, the same procedure was repeated but water was replaced by a paste made of the experimental pellets and water. Approximately 3.5% of body mass was fed to the fish, which was then returned to the respirometers. Oxygen uptake was measured for an additional 4 days.

This fish was placed into the respirometer on the 2009-01-05 and removed on 2009-01-13. The first MO2 after feeding was measured 16:01:12 on 2009-01-09, which was taken at time zero. The first and last MO2 measures were obtained at -97.22 and 88.84 h. Sham-feeding was completed at -25.65 h. Examination of the raw data suggested that only MO2 measurements with a $r^2$ > 0.96 should be considered valid. This particular fish acclimated slowly to the respirometer and it is recommended to exclude the first 24-h of data before calculating SMR. Data recorded during the first 10-h after sham-feeding or after feeding should also be excluded when calculating SMR.

Source

Collected by Denis Chabot at the Maurice-Lamontagne Institute, Department of Fisheries and Oceans, Canada.

References

Chabot, Denis, Koenker, Roger and Farrell, Anthony P. (2016) The measurement of the specific dynamic action in fishes. Journal of Fish Biology 88, 152-172.

Examples

data(codSDA)
plot(MO2~DateTime, data=codSDA)

denis-chabot/fishMO2 documentation built on July 16, 2020, 1:53 a.m.