Worm Breeder's Gazette 14(1): 103 (October 1, 1995)

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

THE EFFECT OF LOW TEMPERATURES DURING EARLY DEVELOPMENT ON LONGEVITY AND FECUNDITY IN THE NEMATODE C. elegans

Vladimir V. Bakaev

box 45, Novosibirsk, 630107, USSR

The purpose of the present experiment is to investigate, how low
temperatures in the early stages of development can influence fecundity,
length of prereproductive period, length of reproductive period, length of
postreproductive period ad mean life span in the nematode C. elegans
(Bristol, N2, wild type). To microtitre wells were added 0,75 ml of liquid
medium with E. coli (OP 50) and 3 adult nematodes. Animals were kept
during 12 hours in the room temperature, then adult nematodes were
discarded and wells were stored in different temperatures during 2
days, then they were transferred in room temperature. Newly appeared worms
were transferred in next wells, every well contains a single nematode. In
every following day these worms were transferred in next wells. All the
experiments were done in the darkness.

Tempe-   Number              Length of                       Mean
rature     of                                                life
  C     progeny        prerepro-   reproduc-    postrep-     span
                       ductive     tive         roductive    days
                       period      period       period                  n
                       days        days         days

21,3  79,8+/-5,4      2,2+/-0,1   8,3+/-0,4    12,8+/-1,1  24,4+/-1,1   26
9,0   77,0+/-5,5      3,3+/-0,1   7,7+/-0,6    11,1+/-1,3  22,8+/-1,5   25
63    67,8+/-3,4      3,8+/-0,1   7,0+/-0,4    11,7+/-1,5  23,2+/-1,5   23
2,0   68,5+/-5,0      4,3+/-0,2   7,1+/-0,4     8,6+/-1,2  21,1+/-1,1   20

Then, lowering of ambient temperatures during early development of
nematode C. elegans resulted in decreasing of progeny. There is a decrease
in the mean life span as temperature during larval development decreased,
as well as the length of reproductive and the length of postreproductive
periods. Then, the length of prereproductive period is increased by
diminishing of the temperature of early development. These results
demonstrate, that the higher is the temperature, the earlier nematodes
started reproduction. These results do not support the widely accepted
point of view, that lowering of temperature increases life span of
different animals. There exist optimal life conditions for species, in
which life span of this species is maximal. But the problem arises: what
must we do in order to obtain the marked increase of longevity and,
probably, immortality? Undoubtedly, it appeared reasonable to seek a new
unusual experimental approaches.
Acknowledment: he author wishes to express his thanks to CGC for providing
C. elegans and E. coli.