PHYSIOLOGY OF THE REPRODUCTIVE CYCLE IN THE COCKROACH BYRSOTRIA FUMIGATA (GUÉRIN)

¹ Department of Zoology, University of Texas, Austin, Texas 78712

1. Four reproductive processes (vitellogenin secretion, yolk deposition, colleterial gland activity and pheromone production) are initiated on about the fifth day after adult ecdysis. There is no apparent sequence of initiation of these processes except that vitellogenin secretion either precedes or occurs concomitantly with the initiation of yolk deposition.

2. Two blood proteins, which are female-specific yolk precursors (vitellogenins A and B), reach a concentration peak on day 16 and then decrease in response to rapid yolk deposition. A second peak on day 22 is thought to represent yolk precursors which were released to the blood as a result of the resorption of some basal oocytes. The vitellogenins are either absent or occur in trace quantities in the blood of pregnant females.

3. Sex pheromone is detectable on the surface of the cuticle by day 10 in 94% of the females tested. Following mating pheromone production is drastically curtailed.

4. Glucoside activity in colleterial glands increases almost linearly from day 8 to 24. After ootheca formation, which involves the utilization of colleterial gland secretion, there is a 78% reduction in glucoside activity.

5. The sequence of events in the reproductive cycle of females of B. fumigata is compared with that of other cockroaches.