الفهرس 
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Abstract
In the present study, two different locations
were studied, one of them is a group of houses in
Haradia Village, and the other is an agricultural field,
about 50 m away from the Village. Both of them
belong to El Maragha District which is about 25 km
away from Sohag, City.
This study has paid attention to identify the
species of rodents in houses and field habitats, their
density, population structure, outbreak, monthly
changes over the two successive years 2013 and
2014, and their effects on agricultural crops in the
field area.
This study has proved that there were four
species in houses area, these were:
(1) Rattus rattus frugivorus.
(2) Rattus rattus alexandrinus.
(3) Arvicanthis niloticus.
(4) Rattus norvegicus.
And three species in the field area:
1. Rattus rattus frugivorus.
2. Rattus rattus alexandrinus
3. Arvicanthis niloticus.
In the present study, the body length, tail length
and the ratio between the body length and tail length
and abdomen colour were used to distinguish
between the different species. The ratio between the
body length and tail length was the most important
classification character that separates the different
species.
Summary
130
Also, the study has proved that the most common
species at houses area was Rattus rattus frugivorus
then Rattus rattus alexandrinus while the two
species: Arvicanthis niloticus and Rattus norvegicus
were the less common.
In the field area the most common species was
Arvicanthis niloticus followed by Rattus rattus
frugivorus and the less common was Rattus rattus
alexandrinus and Rattus norvegicus was not recorded
in this area.
The study proved also that, in big species, tail
length was longer than body length. So, the body
length to tail length ratio was less than ”One”. In the
Rattus rattus frugivorus species it was about 0.85 and
in Rattus rattus alexandrinus species it was about
0.95. In Arvicanthis niloticus species the body length
was longer than the tail length and the ratio was more
than ”one” and about 1.5.
The study also showed an alternate temporal
relationship between Rattus rattus frugivorus and
Rattus rattus alexandrinus. The species Rattus rattus
frugivorus was common in autumn and winter but the
species Rattus rattus alexandrinus was common in
summer and spring. The species Arvicanthis niloticus
didn’t appear except in the beginning of summer and
disappeared in the other months of the year.
In the field area (Rattus rattus frugivorus) was
most common in summer and spring and less in
autumn and winter. Rattus rattus alexandrinus was
common at the end of summer and beginning of
autumn, the end of winter and the beginning of
spring. The species (Arvicanthis niloticus) appeared
Summary
131
in spring and the beginning of summer. (Rattus
norvegicus) didn’t appear at all in the field area.
The study also, proved that in all months, almost
all species have two generations, a young and an
older one. But due to the small collected numbers and
absence of the new recruits, the analysis of study was
difficult and needs more information.
The study paid attention to the effect of the
present species in field area on two kinds of
economic crops: The wheat and maize. The study has
proved that the damage in wheat crop was about
24.3% to 50% in 2013, and 30.6% to 36.8% in 2014.
The percentage of damage was increasing near to
the irrigation cannal and far away from the main
road.
The percentage of damage in maize crop was about
4% to 5.8% in 2013 and 5.2% to 5.8% in 2014. The
percentage of damage was high near the irrigation
canal and decreases away from it, and it was less near
to the main road and increased away from it.
The study showed that the moving ability and
wandering of the present species in the field area