From: Doug Skrecky (oberon@vcn.bc.ca)
Date: Sat May 17 2003 - 21:52:37 MDT
This is the 88'th update of my fly longevity experiments. Average
temperature was 19.9 C during this run. Estimated maximal longevity using
the formula (363 - T*11.2) is 140 days.
Here I test NAD and niacin at doses higher than those used in run #85,
with null results.
I also tried retesting rice protein, both new and old batches.
Previous results in run #56 suggest rice protein is active in prolonging
fly lifespan mostly in the absence of citric acid, which had since become
a standard addition, since this acid keeps the fly food "fresh" and
thereby increases fly lifespan. Unfortunately I added a little extra water
in the current run, in the mistaken belief that the protein might exert a
dehydrating effect. Instead the surface of the fly food became slightly
sticky, which past experience has warned me is not a good thing for fly
longevity. In the presence of citric acid, the rice protein was slightly
detrimental, due I believe to this excess moisture. In the absence of
citric acid, I once again notice a puzzling benefit. Although at acid pH,
absorption of protein is known to be reduced, I suspect the real reason
citric acid counters rice protein, is that the acid pH destroys the active
ingrediant(s) in rice protein.
Run #88 Percent Survival on Day
supplement 37 43 48 53 60 67 72 77 82 89 95 101 106
___________________________________________________________________
control 68 64 41 36 32 14 9 0 - - - - -
NAD 10 mg 33 33 27 20 13 13 0 - - - - - -
niacin 100 mg 32 26 26 26 11 5 0 - - - - - -
niacin 200 mg 26 22 13 9 9 4 0 - - - - - -
rice protein, old 1 tsp 47 41 29 18 12 6 0 - - - - - -
rice protein, new 1 tsp 40 35 20 20 15 5 0 - - - - - -
rice protein, new 2 tsp 30 25 25 25 15 5 0 - - - - - -
-no citric acid control 36 36 29 21 7 7 0 - - - - - -
-rice protein, old 1 tsp 50 50 45 40 35 25 20 20 15 5 5 5 0
-rice protein, new 1 tsp 20 20 20 7 13 13 13 7 7 0 - - -
-rice protein, new 2 tsp 31 15 15 8 8 8 8 8 0 - - - -
This archive was generated by hypermail 2.1.5 : Sat May 17 2003 - 22:04:40 MDT