Intra-puparial development in Oestrus ovis (Diptera : Oestridae)

The phenology of intrapuparial development in Oestrus ovis L. is described, based on 302 specimens collected from the head cavities of goats and reare d in the laboratory at a photoperiod of 12:12 (L:D) h and 32 and 16 degrees C. Dissection and histology of puparia at pupariation and at 3, 6, 9, 12, 15, 18, 21, 24, 30, 36, 42, 48, 66, and 72 h after pupariation and every da y of the intra-puparial period showed that pupariation was achieved in appr oximate to 12 h in heavily pigmented larvae (range, 2-46 h in postfeeding p eriod). Larval-pupal apolysis began immediately after pupariation and was c ompleted by 18-36 h after pupariation (prepupal period). The cryptocephalic pupa was found from this time to the 5th d, when head eversion occurred. P upal-adult apolysis was initiated before head eversion and completed by day 7. The pharate adult presented progressive coloration in compound eyes (tr ansparent, white, yellow, orange, red, brown, silver) while integumental pi gmentation and sclerotization were in progress. Adult emergence occurred at 22 and 23 d in males and females, respectively. Changes in the weekly pupa rial weight of specimens reared under both field and laboratory conditions was described. It was concluded that although the intra-puparial developmen t of O. ovis displayed some unique characteristics, it was essentially simi lar to other cyclorraphous flies. The actual pupal period of O. ovis lasted from the 2-7 d postpupariation, whereas approximately two-thirds of the in trapuparial period was used for the maturation of the pharate adult.