The effect of temperature on the consumption of fat during pupal development inGlossina.

Abstract

The larva of the tsetse fly is nourished by a maternal secretion rich in lipoid (Hoffmann, 1954) and at the time of deposition it contains extensive reserves of chloroform-soluble substances, which will henceforth be referred to as fat. This fat constitutes the sole source of energy during pupal development (Bursell, 1958) and that which remains at the end of development makes up the greater proportion of the food reserves available to the fly prior to its first blood-meal. It is clear that any factor which affects the amount of fat consumed during development will influence the length of life of the newly emerged fly and hence its chance of obtaining a blood-meal. Temperature could be such a factor and, to estimate the magnitude of the effect, the fat content of newly emerged flies was determined following development at different temperatures. Material and methods.Most of the experimental work was done with puparia t of Glossina morsitans Westw. bred from females maintained in the laboratory. Puparia were recovered from the breeding tubes and weighed less than 10 hours after larviposition; they were kept in incubators at the stated temperatures until the flies emerged. The normal rhythm of emergence (Bursell, 1959a) appears to be abolished when puparia are kept at constant temperature, the flies emerging indifferently at all hours. The incubators were inspected at regular intervals from early morning till about 2200 hr., so that during this period flies were recovered soon after emergence. They were kept under observation at about 25°C. until they had reached the stage of being capable of flight and were then killed with potassium cyanide. Of the flies that emerged during the night, only those that were not yet capable of flight at the first inspection were included for analysis.After the flies had been killed, fat content and non-fatty dry weight (referred to as residual dry weight) were estimated by methods described elsewhere (Bursell, 1959a). Eegressions of fat contents on residual dry weight were calculated and samples compared at specified levels of this measure of size. As will be shown below, the relation between size and fat content is not rectilinear over the whole range of size, but within the restricted ranges over which regressions were calculated this departure from rectilinearity was not statistically demonstrable, and failure to take account of it is unlikely to affect the conclusions drawn.In attempting to relate present findings to the biology of tsetse flies under natural conditions it will be assumed that normal shade temperatures give a * Now at Department of Zoology, University College of Rhodesia and Nyasaland, Salisbury, Southern Ehodesia.t To avoid continual circumlocution, the word " puparium " will be used to denote the pupa-rial shell and its contents, whether these comprise a third-or fourth-instar larva, a pupa or pharate adult.

Stoichiometric estimates of the biochemical conversion efficiencies in tsetse metabolism

“…Puparia of Glossina morsitans orientalis Vanderplank consume roughly 4200 mm 3 oxygen total during this phase of their lifecycle [49] and use approximately 2.0 mg fat [50]. From the calculations presented here, the conversion of 2.0 mg fat to energy would require 4400 mm 3 oxygen which falls within 5% of the measured result, again validating these estimates.…”

Effect of temperature on the ovarian development in the pupa of Glossina pallidipes Austen II: Influence on the reversed sequence of egg follicle maturation

“…The high, significant positive correlation between the frequency of these abnormal sequences and temperature (Fig. This was in spite of the fact that the constant temperatures used were all well within 16-32°C, the natural reproductive range of tsetse (Bursell, 1960). This was in spite of the fact that the constant temperatures used were all well within 16-32°C, the natural reproductive range of tsetse (Bursell, 1960).…”

Temperature‐dependent lipid metabolism in the blow fly Lucilia sericata

“…For example, in the fire ant, Solenopsis xyloni (Hymenoptera: Formicidae), lipid losses of 35% were observed during pupation (Wheeler & Buck, ). An optimal temperature probably exists for every insect species, at which energy reserves are utilized most efficiently, the value of which is likely to be defined by enzyme kinetics (Bursell, ). Merkey et al .…”