METHOD
Measuring oxygen concentration: One glass vial was filled with 7-13 Artermia. After incubation, uncapped at 15oC for 5 minutes, the glass vial was sealed underwater and incubated again for another 5 minutes. After this 5-minute incubation, a reading of oxygen concentration was taken via a fibre-optic cable held onto a sensor spot on the vial. The vial was then returned to the incubation bath. The first reading represented time zero and subsequent readings were taken every 5 minutes for 20 minutes. After the last measurement, the artemia were poured onto a watch glass and their lengths were measured individually under a dissecting scope and category noted. A fresh batch of artemia was then selected and the process repeated with incubation at 25oC. The length-specific consumption rate was calculated and a column graph was produced with average values calculated from collated from class results.
Measuring movement speed: Pre-recorded videos of Artemia moving in a jar at cold and warm temperatures were opened using a Tracker application. A time point and animal was chosen in the video and its movement was tracked across 30 frames. The average was taken and this was repeated for 5 animals at 15oC and 25oC. The calculated average velocity of the animal was also collated with class results and recorded in a table
RESULTS
Length-specific O2 consumption rate was shown to be slightly higher in the warmer temperature of 25oC compared to the O2 consumption rate of artemia at 15oC (Figure 1). Contrastingly, the opposite applies for velocity, with the artemia in the colder environment of 15oC showing faster speeds of movement in comparison to the artemia subjected to a temperature treatment of 25oC (Table 1).
Temperature (oC) | Average Velocity (mms-1) | Standard Deviation | 15 | 12.057 | 5.287 | 25 | 11.568 | 5.430 |
Table 1. The average velocity of artemia submitted to different temperature treatments measured