Evaluation of four pediculicides against the head lice Pediculus h. capitis.

Four pediculicides were tested against head lice in-vitro. The LT50 for Licid ranged between 10.75 (at conc. 50%) to 25.08 (at conc. 1%). All lice died with conc. 100% within 5 minutes. With Malathion, the LT50 ranged between 4.23 to 9.3 at conc. 50% to 1% respectively. All lice died with conc. 57% within 3 minutes. With Benzanil, the LT50 ranged between 20.85 to 44.34 at conc. 50% to 1% respectively. All lice died at conc. 2.5% within 10 minutes. With Para plus, the LT50 ranged between 18.46 to 29.5 at conc. 100% to 50% respectively. All lice died with conc. 100% within 30 minutes. So, the least time needed to kill all lice was given with Malathion (3 minutes). The least dose of pediculicide needed to kill all lice was those of Benzanil (1% = 0.025) and Malathion (1% = 0.57). The whole results were discussed regarding the advantages and disadvantages of these pediculicides.

Morphological studies on Phlebotomus papatasi (Scopoli) in Riyadh City, Saudi Arabia.

In general, leishmaniasis is more or less a problem not only in Saudi Arabia but also in all countries of the Eastern Mediterranean Region. In Saudi Arabia, the most important form is zoonotic cutaneous leishmaniasis (ZCI.). It's main vector, Phlebotomus papatasi has been reported and incriminated by many authors. In this paper, the diagnostic morphology of P. papatasi as compared to other species found in Riyadh as well as the immature stages was given. This is considered as a base line data for studying the ecology and biology of P. papatasi. No doubt the best control strategy is based on complete understanding of the insect vector of ZCL.

The seasonal and daily activities of Phlebotomus papatasi in Riyadh, Saudi Arabia.

The seasonal abundance of P. papatasi was determined by monthly collection. It was found that the greatest number of sandflies occurred most commonly during the summer season with a peak in June and another one in September. Male to female ratio was 1:1.25 in Riyadh and 1:1.48 in Al Kharj. During the winter season no insect was found and then the population density started to appear again from March. The daily indoor activity of P. papatasi was in May, in the periphery of Riyadh city, showed largest amount of Phlebotomus from 10-11 pm. with sex ratio (male to female) 1:3.5 and from 4-5 am. with a sex ratio (male to female) 1:3. In the central area of Riyadh city, the highest number was from 9-11 pm. with a sex ratio (male to female) 1:3.5 also from 4-5 am. with sex ratio 1: 3. The daily outdoor activity was in June, in the peripheral area in Al Kharj city, showed the highest number from 7-9 pm. with a sex ratio (male to female) 1: 2.3 and from 5-7 am. with a sex ratio 1:1.3, while in the central area of Al Kharj, the highest number was from 7-9 pm. with a sex ratio 1: 1.1 and from 5-7 am. with a sex ratio 1: 0.9. Both the indoor and outdoor collections showed that the number of females P. papatasi were higher than number of the males, and the sandflies were more abundant in the periphery than in the central of both Riyadh and Al Kharj cities.

Rodents and their ectoparasites in Sharkia Governorate, Egypt.

Rodents serve as reservoir hosts for many parasitic and bacterial diseases which are spread to man and animals by their habits, their droppings or by their arthropod ectoparasites. Commensal (semi-domestic) rodents were collected by different methods from Sharkia Governorate over a period of one year, 1989. The trapped rodents in descending order of prevalence were Rattus norvegicus, Rattus rattus, Mus musculus and Gerbillus gerbillus. The ectoparasites were collected and identified as five species of fleas, one species of lice and one species of mites. The role of these rodents as animal reservoirs and their ectoparasites as vectors of zoonotic diseases was discussed.

Effect of Altoside (ZR-515) on oxygen consumption, carbon dioxide out put and carbohydrate content of organophosphorus resistant strain of Musca domestica.

The effect of applying JHA ZR-515 at a concentration of 50 microliter/liter water in the larval rearing medium from the first larval instar on oxygen consumption, carbon dioxide out put and total carbohydrates was studied. The oxygen consumed by the pupae previously treated as larvae with ZR-515 was decreased and no adult could emerge. The carbon dioxide out put seems to follow a more or less the pattern of oxygen consumption. The concentration of total carbohydrate content in one day old pupae previously treated as larvae was significantly lower than normals. In three days old there was a marked significant increase and in five days old, the carbohydrate content was significantly higher than controls.

Immunohistochemical evidence of gastro-entero-pancreatic neurohormonal peptides of vertebrate type in the nervous system of the larva of a dipteran insect, the hoverfly, Eristalis aeneus.

Using rabbit and guinea-pig antisera, raised against GEP neurohormonal peptides of mammalian origin, cells were observed in the brain and/or in the fused ventral ganglia of the last (fifth) larval instar of the hoverfly, Eristalis aeneus, being immunoreactive with antisera against insulin, somatostatin, glucagon, PP, secretin, gastrin/CCK/caerulein; substance P, enkephalin and endorphin. Most of these GEP neurohormonal peptides also occurred in nerve fibers. No immunoreactive cells or nerve fibers could be detected with antisera against GIP, VIP, (the central fragments of) CCK, bombesin or neurotensin. The antisera tested failed to reveal any immunoreactive cells or nerves in Weismann's ring (fused corpus allatum/corpus cardiacum and thoracic gland) or in different parts of the alimentary tract. The observations support the hypothesis that neuronal GEP hormonal peptide production in the brain is a genuinely original mechanism and the appearance of endocrine cells in the gut a later feature in evolution.