X-Message-Number: 22313
Date: Sat, 9 Aug 2003 09:55:07 -0700 (PDT)
From: Doug Skrecky <>
Subject: 99'th update on fly longevity experiments

    This is the 99'th update of my fly longevity experiments. Average
temperature was 22.4 C during this run. Estimated maximal longevity using
the formula (363 - T*11.2) is 112 days.
    Exposure to sunlight reduces some measures of immunity in mammalian
skin. Since viral infections are my main proposed controlling factor in
early fly lifespan, I decided to test whether keeping some flies in
darkness could increase their survival, at least early in the experiment.
Vitamin D deficiency can lower immunity, I also added a skim milk bottle
to see if adding a little extra vitamin D could further improve survival.
    Early (22 day) survival in dark control was indeed increased, but
adding skim milk offered no benefit then. Milk may have been beneficial
by the day 44 census. Milk was toxic with regard to maximum lifespan back
in run #91 as well, but this result was not yet available when I started
this experiment.
    It is interesting that the normal control bottle had the highest
maximum longevity. However this result was due to only one fly. If this
single animal is ignored then no significant differences in maximal
longevity were evident in any bottle. Soya bean drink may have slightly
reduced early survival.
    Pomegranate was dissapointing in this run, but it was an very old
bottle of pomegranate paste that was used, instead of a fresh one, which
may have skewed the results.

Run #99                              Percent Survival on Day
supplement                      22 27 33 39 44 49 55 60 65 72 78 83 88
______________________________________________________________________
control                         82 82 77 64 41 32 27 27 23 14  5  5  0
almond juice                    80 70 55 55 50 45 40 35 20  0  -  -  -
dark control                    93 86 71 36 36 36 36 29 21 14  0  -  -
 +skim milk                     80 80 75 70 60 45 40 25 25 10  0  -  -
 ++annatto 1/8 tsp + B3 100 mg 100 94 94 88 88 82 35 18 12  6  0  -  -
 ++pomegranate 1/2 tsp          89 89 89 89 78 78 44 33 33 11  0  -  -
oat drink                       82 76 70 70 64 52 27 24 15  3  0  -  -
soya bean drink                 69 69 56 56 50 50 25 13 13  0  -  -  -
sugar beet syrup 1/8 tsp        82 76 76 59 53 53 41 35 18 12  0  -  -
sugar beet syrup 1/2 tsp        69 56 56 44 44 44 31 31 31 13  0  -  -

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