Some observation on rodents and their fleas in suez area, U.A.R.

ABSTRACT

Suez district being a main receptive area of rat-borne diseases, warrants special attention and regular study of its rodent population and ecto-parasites. The present investigation attemps to reveal the present status of domestic and commensal rodents and their fleas both qualitatively and quantitatively in the distinct environments of this area. The rodent index was found to differ from one locality to another depending on the sanitary conditions and adequacy of antirat measures. Also the frequency of the various species differs, depending on the prevailing environmental conditions. A negative relationship was observed between the frequency of R. norvegicus and that of the three subspecies of R. rattus. Also it was noticed that Acomys cahirinus and A. dimidiatus can coexist in certain localities. Nevertheless the former species prevails more in rural areas, whereas the latter dominates in desert settlements. Amongst the important conclusions, a direct relationship was observed between the percentage frequency of a given species and the pregnancy rate among its females. The percentage immature can be also taken as an indirect measure of the growth in size of a given population. As regards fleas, it was noticed that the Norway rat which represents the most frequent rodent host, revealed the highest density of flea infestation. Again, this was found to differ from one milieu to another. On the other hand, the small rodent species, viz., M. musculus, and Acomys spp. showed very low flea densities which may account for a minimum role as flea carriers. X. cheopis constitutes the most dominant flea infesting rodents of this area, Ct. felis, Ct. felis strongylus and Papapulex chephrenis were occasionally met with. Females of the rodent host showed higher flea densities and again female fleas were found more abundantly than males. Ultimately, it may be stated that the rodent population being dynamic and affected with multitude of factors is so liable to change and should be always kept under strict supervision especially in receptive areas like sea ports