POPULATION DYNAMICS AND REPRODUCTION ASPECTS OF THE NILE RAT, ARVICANTHIS NILOTICUS

Population dynamics, maturity status , sex ratio and female and male conditions of the Nile rat , A. niloticus were studied during 1988­1989 in Minia governorate . The adults of the Nile rat appeared more abundant than juvenile individuals during the whole year. Mean numbers of entrapped inidividuals of both stages of the nile rat and their relative percentages recorded in winter, summer, autumn and spring were : 42 individuals and 29.6 %, 43.7 individuals and 28.5%, 48.7 individuals and 30.6% , and 55.3 individuals and 35.8%, respectively . There was no significant difference between the numbers of females and males of Arvicanthis niloticus . Pregnant females were found from February to No­vember . Mean of featus per female had a positive correlation with per­cent of pregnant females. Potent males were found for nearly the whole year which corresponds with the pregnancy cycle of females . Spring and autumn were more suitable for the Nile rat reproduction than summer and winter seasons.