Manchester, 6/15

Screening day.

Some hiccups, but nothing devastating. Grace screening, Olivia working buckets/setup, me sampling/counting. Initial visual inspection of larval buckets look like larvae aren’t doing as well as they were last week. But, we’ll see!

Screening data: image image

Snafoo: the SN-10 Ambient group was mislabeled as SN-10 Low, and before realizing I stocked the 224um larvae (of which there were ~30k!) in the SN-10 Low setting tank. This error was caught moments later, and labeling/data entries were corrected. Unfortunately, the SN-10 Low setting tank, which had been stocked with ~4,300 larvae since 6/5 and which I know there were still swimmers, is now mixed with ~30k SN-10 Ambient larvae. I started a new SN-10 Low setting silo. I kept the mixed up batch, labeled as such. Most of the animals in this group are from SN-10 Ambient.

Collected new larvae:

image

Started larval growth experiment

All four SN treatment groups spawned considerably today… image

… so I set up a larval growth experiment similar to Katherine’s 2015 growth trial. Here’s the gist: I grow a small amount of larvae in tripours and sample at day 0, 7 & 14, image and measure growth rate. Larvae are stocked at 1/mL, and water is changed daily with fresh FSW+algae at 100k cells/mL. I have access to handy little silos that fit perfectly in a tripour (THANKS STUART!), which makes water changes a breeze - simply transfer the silo to a new tripour with fresh water. Preparing the new water takes a bit of time, as I first count the algae density to ensure 100k cells/mL.

Filled the tripours to 800 mL, and stocked 800 larvae per tripour. Using the above counts I determined the volume needed for 800 larvae. Grace used a large plastic pipette and plunged/stocked triplicates from each group:

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Harvested and counted algea and added 33 mL algae cocktail to each tripour.: image

Written on June 15, 2017