4 22 2015 Heat/Mechanical Shock Experiment

Today I ran the Heat and Mechanical Shock experiment on my oysters. While most groups got liquid nitrogen treatment, the mechanical H and S groups did not due to lack of Liquid N2. For those samples I placed them on ice and moved them to the -80 as soon as possible.  The procedure went as follows.

Pre-Experiment

Oysters

• 8°C
• fed daily with 5-10 ml per tank commercial shellfish diet (Isochrysis 1800 mix Marine Algae)
• Partial water changes once per week (remove 5 gallons, replace with fresh 5 gallons)
  • Seawater from Seattle Aquarium
• Aeration with aquarium aerator/stone
• circulation with underwater pump
• Tanks 10 gallon plastic storage tubs (costco storage tubs)

Homogenization tubes for ctenidia prelabelled with date (42215,42315), pop (N,H,S), treatment (T,M) and time point (1, 24) or Control, and oyster # (1,2,3...)

Collection 1.5 ml tubes (screw cap) for ctenidia prelabelled with date (42215,42315), pop (N,H,S), treatment (T,M) and time point (1, 24) or Control, oyster # (1,2,3...), and tissue type (C, M)

Collection 1.5 ml tubes (screw cap) for mantle prelabelled with date (42215,42315), pop (N,H,S), treatment (T,M) and time point (1, 24) or Control, oyster # (1,2,3...), and tissue type (C, M)

15 ml conical tubes for whole oyster prelabelled with date (42215,42315), pop (N,H,S), treatment (T,M) and time point (1, 24) or Control, and oyster # (1,2,3...)

Warm fresh seawater in 500 ml beaker to 38°C by immersing it in a water bath at 38°C.

Experiment

Heat Stress

• 22 oysters each pop in a mesh bag were lowered (stagger each pop by 1 hour) into 500 ml of prewarmed 38°C sea water (1 hr timer started)
  
  • N pop first, H pop next, S pop last
• after 1 hour exposure heat stress ends, animals returned to 8°C water.
• 1 hour post exposure 8 animals sampled from each group staggered by 1 hour
  • N pop first, H pop next, S pop last
  • collected with ethanol flame sterilized forceps and scissors
    • tools kept in 100% EtOH
    • ran through EtOH flame
    • allow EtOH to burn off
    • Collect tissue
    • replace in 100% EtOH
    • wipe occasionally with paper towel and resterilize
  • ctenidia sample (50-100 mg) homogenized in 1 ml Trizol stored at -80°C
  • 2nd ctenidia sample (any remaining) in 1.5 ml screw cap tube dropped into liquid nitrogen then to -80°C
  • mantle sample (decent size) in 1.5 ml screw cap tube dropped into liquid nitrogen then to -80°C
  • remaining tissue placed in 15 ml conical with 75% EtOH at -20°C
  • shells in individual labeled ziploc bags so correspond to sample including oyster id

Mechanical Stress

• 22 oysters from 1 pop placed in bucket in centrifuge and spun for 5 minutes at 1000 rpm.  Samples staggered by 1 hour. Completed after all heat shock treatments and samples were taken.
  • N pop first, H pop next, S pop last
• after 5 minutes of mechanical stress, animals returned to 8°C water
• 1 hour post exposure 8 animals sampled from each group staggered by 1 hour
  • N pop first, H pop next, S pop last
  • collected with ethanol flame sterilized forceps and scissors
    • tools kept in 100% EtOH
    • ran through EtOH flame
    • allow EtOH to burn off
    • Collect tissue
    • replace in 100% EtOH
    • wipe occasionally with paper towel and resterilize
  • ctenidia sample (50-100 mg) homogenized in 1 ml Trizol stored at -80°C
  • 2nd ctenidia sample (any remaining) in 1.5 ml screw cap tube dropped into liquid nitrogen then to -80°C
  • mantle sample (decent size) in 1.5 ml screw cap tube dropped into liquid nitrogen then to -80°C
  • remaining tissue placed in 15 ml conical with 75% EtOH at -20°C
  • shells in individual labeled ziploc bags so correspond to sample including oyster id