الفهرس 
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Abstract
I -Survey study:-
The captured rodents throughout four successive years from 2003 to 2006 in the surveyed localities (El-Edwa, Samallout, Minia and Mallawy) were classified into species and subspecies. according to Schwartz (1960). The occurrence percentages were recorded by dividing the number of the captured species or subspecies from the total numbers the captured rodents.
The rodents recorded in the all tested localities and years were Rattus norvegicus, Rattus r. frugivorous, Rattus r. alexandrinus and Mus musculus. The highest occurrence percentage (54.5%) was recorded with Rattus r. frugivoroius in El-Edwa during 2006. This subspecies recorded the highest average percentage (47.28%) during the surveyed years. In contrast, the lowest average percentages (0.0, 0.35, 0.80 and 1.77%) were observed with Arvicanthus niloticus in Sammallout, El-Edwa, Mallawy and Minia, respectively.
Acomys c. cahirinus and Arvicanthus niloticus disappeared from 2003 to 2005 in El-Edwa. On the other hand Arvicanthus niloticus disappeared in Mallawy samples from 2005 to 2006. The field may be due to considered the field rodents and not entres the buldings to get the food only and go out to the field. The highest occurrence of Rattus norvegicus (15.1 %) was registered in Minia locality because the species preferred the organic methods and stay in buldings .
II-Studies on the population dynamics of the common species during the years of study:
Population dynamic of rodents was assessment as trap index in habitation masses in Mania Governorate during the study period from the year of 2003 to 2006.
A- Seasonal fluctuations in the population density
1- Seasonal fluctuations in the population density of rodents species (Rattus rattus, Rattus norvegicus and Mus musculus) during 2003:-
The seasonal study throughout the four successive years for all species (Rattus rattus, Rattus norvegicus and Mus musculus) showed that the highest density was observed during autumn especially in September followed by summer in Jun then during spring in March for the three tested species.The highest densities i.e. 0.45, 0.090 and 0.052 with R.rattus, R. norvegicus and M. musculus were realized in September 24 and 10. The low densities were noticed through winter months especially in January and 1th, recording 0.05, 0.01 and 0.008 trap index with R. rattus, R. norvegicus and M. musulus, respectively. three annual abundance periods of R. rattus were registered under the Minia Governorate conditions. The first abundance period was found to be from 29th of January to 9th of April 2003 .The second abundance period started from 23rd of April to 16th of July 2003. The third abundance period appeared from 16th of July to 31st of December 2003.
As for as the Norway rat, R. norvegicus, had four abundance periods could be registered. The first abundance period was initiated from 15th of January to 26th of February and the second abundance period was from 12th of March to 23rd of April, While the appearance of the third abundance period was on 7th of May and continued to 16th of July.The fourth and last abundance period of R. norvegicus was from 30th of July to December .
The house mouse, M. musculus surpassed the other rats in the number of annual abundance periods . This species completed five abundance periods throughout the year of 2003 under Minia conditions as follow: First abundance period was from First of January to 26th of March, The second abundance period was from 9th of April to 21st of May, The 3rd abundance period was from 4th of Jun to 16th of July, 4th peak was from 30th of July to 8th of October The last abundance period was from 22nd of October to the thirty one of December.
2-Seasonal fluctuations in the population density of rodents during 2004:-
The high density was attained with R. rattus species followed by R. norvegicus while M. musculus was the least density. It was obvious that all rat index was recorded during 2004 were less than other recorded in 2003. The seasonal study throughout the year of 2004 for all species showed that the highest density was observed during autumn especially in September. Whereas the highest densities as rat index of R.rattus, R. norvegicus were 0.220, and 0.045 in the 23rd of September and the high density of M. musculus was 0.033 in 9th of September. The low densities were noticed through winter months especially in January. In 29th of January, R. rattus rat index was 0.025 while the other two rats, R. norvegicus and M. musulus attained the low densities 0.005 and 0.004, respectively in the 1st of January. It may be due to the colled wheather and the rodents preferred to stay on there borrows and not appeure.
Three annual abundance periods of R.. rattus were also distinguished under the Minia Governorate conditions during 2004. The first abundance period was found to be from 29th of January to 8th of April .The second abundance period started from 22nd of April to 15th of July. The third abundance period took long time (12 weeks) from 29th of July to 30th of December 2004.
As for as the Norway rat, R. norvegicus, had four abundance periods could be registered. The first abundance period initiated from 1st of January to 26th of February and the second abundance period was from 11th of March to 22nd of April, while, the appearance of the third abundance period was on 6th of May and continued to 15th of July. The fourth and last abundance period of R.. norvegicus was from 29th of July to 30th of December.
The house mouse, M. musculus surpassed the other rats in the number of annual abundance periods . This species completed five abundance periods throughout the year of 2004 under Minia conditions as follow: First abundance period was from 1st of January to 25th of March, 2nd abundance period was from 8th of April to 20th of May, 3rd abundance period was from 3rd of Jun to 15th of July, 4th abundance period was from 29th of July to 7th of October and 5th abundance period was from 21st of October to the 30th of December .
3-Seasonal fluctuations in the population density of rodents during 2005:-
The seasonal study of the dominant rodents i.e. Rattus rattus, Rattus norvegicus and Mus musculus throughout the year of 2005 show that the high density was attained with R. rattus followed by R. norvegicus while M. musculus was the least density. The seasonal study throughout the year of 2005 for all species showed that the highest density was observed during autumn especially in September whereas the highest densities as rat index of R.rattus, R. norvegicus were 0.315, and 0.063 in the 24th of September and the high density of M. musculus was 0.045 in 10th of September. The low densities were noticed through winter months especially in January. In 29th January R. rattus rat index was 0.035 while R. norvegicus and M. musulus attained the low densities 0.007 and 0.006 rat index in the 1st of January and 12th of February, respectively .
It could be concluded that three annual abundance periods of R. rattus were registered under the Minia Governorate conditions. The first abundance period was found to be from 29th of January to 9th of April 2005 .The second abundance period started from 23rd of April to 16th of July. The third abundance period took long time (12 weeks) from 30th of July to 31st of December 2005.
In concerns of the Norway rat, R. norvegicus, four abundance periods could be registered. The first abundance period initiated from 1st of January to 26th of February and the second abundance period was from 12th of March to 23nd of April, while the appearance of the third abundance period was on 7th of May and continued to 16th of July.The fourth and last abundance period of R. norvegicus was from 30th of July to 31st December.
The house mouse, M. musculus surpassed the other rats in the number of annual abundance periods . This species completed five abundance periods throughout the year of 2005 under Minia conditions as follow: 1st abundance period was from 12th of February to 26th of March, 2nd abundance period was from 9th of April to 21st of May, 3rd abundance period was from 4th of Jun to 16th of July, 4th abundance period was from 30th of July to 8th of October and 5th abundance period was from 22nd of October to the 31st of December.
4-Seasonal fluctuations in the population density of rodents during 2006:-
Throughout the year of 2006 the seasonal study of the dominant rodents i.e. Rattus rattus, Rattus norvegicus and Mus musculus indicate that the densities of the all tested rats were high than the other recorded in the previous years (2003, 2004 and 2005).The density of R. rattus surpassed the other of R. norvegicus while M. musculus density was less in the density than R. norvegicus. The seasonal study throughout the year of 2006 for all species showed that the highest density was observed during autumn especially in September whereas the highest densities as rat index of R.rattus, R. norvegicus were 0.720, and 0.144 in the 23rd of September and the high density of M. musculus was 0.102 in 9th of September. The low densities were noticed through winter months especially in January. In 29th January R. rattus rat index was 0.080 while R. norvegicus and M. musulus attained the low densities 0.016 and 0.010 rat index in the 15th of January and 30th of December, respectively.
Under the Minia Governorate conditions R. rattus attained three abundance periods. The first abundant period was found to be from 29th of January to 8th of April 2006 .The second abundance period started from 22nd of April to 15th of July 2006. The third long abundance period (12 weeks) was from 29th of July to 30th of December 2006.
Norway rat, R. norvegicus recorded four abundance periods . The first abundance period initiated from 15th of January to 26th of February and the second abundance period was from 11th of March to 22nd of April, while the appearance of the third abundance period was on 6th of May and continued to 15th of July. The fourth and last abundance period of R. norvegicus was from 29th of July to 30th of December.
The house mouse completed five abundance periods throughout the year of 2006 under Minia conditions as follow: 1st abundance period was from 292th of January to 25th of March, 2nd abundance period was from 8th of April to 20th of May, 3rd abundance period was from 3rd of Jun to 15th of July, 4th abundance period was from 29th of July to 7th of October and 5th abundance period was from 21st of October to the 30th of December.
B-The effect of the daily mean temperature and relative humidity on the population of rodents during the years from 2003 to 2006:-
1-The effect of the daily mean temperature and relative humidity on the population of R. rattus during the years from 2003 to 2006:-
Correlation values between R. rattus population densities and the daily mean temperatures were posotive for the all periods in the tested years. The high but insignificant correlation values, + 0.6980 and +0.7335 were recorded in the 1st period that continued during winter and spring seasons of 2004 and 2006, respectively, while the correlation coefficient values were low in the 1st period of 2003 and 2005 recording +0.2672 and +0.1908, respectively.
Simple regression values of R. rattus rat index on the daily mean temperature during 2003-2006 were positive and insignificant and this means that the daily mean temperatures were around their optimal ranges of R. rattus activity. It is worth to mention that the increament ratios in the population of R. rattus were high in the 1st period during spring of 2004 and 2006, whereas the increase of 1ºC in the departure of the daily mean temperature caused an increase of 0.0186 and 0.0267 rat indices, respectively.
Negative correlation values between R. rattus density and the daily mean relative humidity were registered with the whole studied periods. High correlation values are shown with the 1st periods during spring months in the all studied years especially in 2003 and 2005, whereas the relative humidity effects were negative and highly significant recording -0.9050 and -0.9363, respectively.
It could be concluded from the regession of R. rattus population density on the daily mean relative humidity that an increase of 1 % in the departure of relative humidity caused the highest drop in the average rat index by 0.0132 and 0.0174 in the first abundance period of 2003 and 2005, respectively.
2-The effect of the daily mean temperature and relative humidity on the population of Rattus norvegicus as rat index during the years from 2003 to 2006:-
Statistical analysis of data showed positive correlation between the daily mean temperature and the density of R. norvegicus. In 1st period during the winter seasons of 2003 and 2004, correlation coefficient (r) values were low recording +0.1545 and +0.1134, respectively, while in the 2nd abundant period during spring season of 2003, 2005 and 2006, the correlation coefficient values were high but insignificant recording, +0.6572, +0.6675 and +0.5059, respectively. During the 4th abundant period from the end of July to the end of December moderately correlation values i.e. +0.4268, +0.4780, +0.2057 and +0.4663, were recorded in 2003, 2004, 2005 and 2006, respectively
Simple regression values of R. norvegicus rat index on the daily mean temperature during 2003-2006 were positive and insignificant and this means that the daily mean temperatures were around their optimal ranges of R. norvegicus activity. It is worth to mention that increment ratios in the population of R. norvegicus were high in the 2nd period during spring season, whereas the increase of 1ºC in the departures of daily mean temperature caused noticed increments of 0.0021, 0.0012 and 0.0027 in the density of R. norvegicus during 2003,2005 and 2006 , respectively.
Computing the “r” values between the daily mean relative humidity and the rat index of R. norvegicus revealed that the “r” values were negative with the whole studied abundance periods and these values were moderately and insignificant in the 1st period during 2003, 2004 and 2005 recording -0.4819, -0.3730 and -0.3417, respectively but the correlation value was high and insignificant (-0.7642) with the 1st period of 2006.
Regression values were also negative and insignificant with the whole studied periods, this means that the daily mean relative humidity was around its optimal range of R. norvegicus activity. The daily mean relative humidity that increased 1% in the departure caused high decrease (0.0021 and 0.0016) in R. norvegicus density during the 1st and 4th periods of 2003 and 2004, respectively. While the highest depressions (0.0013 and 0.0084) in R. norvegicus density were recorded with the 2nd periods of 2005 and 2006.
3-The effect of the daily mean temperature and relative humidity on the population of Mus musculus as rat index during the years from 2003 to 2006:-
The high correlation values between M. musculus population densities and the daily mean temperatures were recorded in the 5th period of 2003, the 2nd period of 2004 and 2005 as well as the 1st period of 2006, these values were +0.5967,+0.9564, +0.8554 and +0.9124, respectively. The low correlation values were recorded in the 4th abundance period in the summer, whereas these values were +0.0505, +0.1308 and +0.0235 in 2003, 2005 and 2006, respectively. While in this period of 2004, abnormale correlation value (+0.6604) was recorded.
As for regression of M. muscles population density as rat index on the daily mean temperature during the course of work, it was obvious that all regression values were positive and insignificant except the regression values with the 2nd period in 2004 and the 1st period in 2006, they were significant, recording +0.007 and +0.005, respectively. The high effect of temperature was clear in these periods (2nd of 2004 and 1st of 2006) whearas the increase of 1ºC in the departure of the daily mean temperature caused an increase of 0.007 and 0.005 rat index in these periods, respectively. It is worth to mention that all daily mean temperatures were around the optimal range of M. musculus activity except in the 2nd and 1st periods of 2004 and 2006, respectively.
The correlation values between the daily mean relative humidity and M. musculus density were negative with the all tested periods. The high correlation values were in the 2nd periods of 2004 and 2005, recording -0.9129* and -0.6444, respectively, while the highest correlation values in 2003 and 2006 were with the 3rd period of these tested years recording -0.8857 and -0.9728**, respectively.
Regressions of M. muscules density on the mean relative humidity indicate that the high regression values, -0.0020, -0.0017, -0.0021 and -0.0064* were attained in the 3rd, 4th, 1st and 3rd abundance periods of 2003, 2004, 2005 and 2006, respectively. Regression values of the daily mean relative humidity were insignificant during the whole studied periods except the 3rd period in 2006 and this means that the daily mean relative humidity was around its optimal range of M. musculus in the most studied periods.
C-Seasonal abundance and yearly fluctuation of rodent communities in Minia governorate during the study period from 2003 to 2006 :-
The highest densities of rodents in all tested localities were observed in spring and autumn followed by summer and the least density was observed during winter. The low density appeared through the hot dry seasons in summer and the other cool seasons in winter. The population densities of rodents during the period from 2003 to 2006 fluctuated between 0.269, 0.130, 0.174 and 0.319 in 2003, 2004, 2005 and 2006, respectively. During the tested years from 2003 to 2006, the highest mean density (0.3185) was attained in Mallawy district followed by the mean densities, 0.2525, 0.1652 and 0.1560 in Minia, Samallout and El-Edwa districts, respectively .
III: Damage caused by rodents in maize and sorghum :-
Damage percentages caused by rodents in maize were high than those in sorghum. Damage percentages of rodents against maize or sorghum were significantly recorded in the outer 6 meters toward the canal and the road, recording 29.5 and 24.73 % in maize, while in sorghum the damage percentage means were 23.3 and 19.5, respectively.
The damage toward the canal surpassed the damage toward the road, and the damage was high in the border than inside the field. Means of the damage percentages in maize were in the descending order recording 29.50, 20.44, 14.26, 1.41, 0.94 and 0.47% at the distances of 6, 12, 18, 24, 30 and 36 meters from the canal, respectively. While the damage percentages at similar distances toward the road were 24.73, 13.76, 9.5, 0.94, 0.47 and 0.0 %, respectively.
The average of damage percentages in sorghum were less than other recorded with maize and were also in descending order recording 23.3, 17.10, 11.86, 0.86, 0.47 and 0.47% from canal as well as 19.5, 12.8, 9.5, 0.47, 0.47 and 0.0 % from the road, respectively
The peak of damage had attained in 13th of July, with maize and sorghum plants. Negative simple correlation was recorded between the rate of damage and the distances from the canal or the road and the correlation values were significant or highly significant varied according to the time of the sampling during the different growth stages of maize or sorghum plants
IV: Loss of maize and sorghum yields caused by rodents in El-Edwa district during the year of 2005:-
In the end of the season percentages of yield loss were estimated for 30 plants at the distances of 6, 12, 18, 24, 30 and 36 meters from the two edjes of the field toward the canal and toward the road.
The loss caused by rodents in maize yield surpassed the loss of sorghum yield. The loss of maize or sorghum yield was oppositely relative to the distances from the field edjes, toward the canal or the road.Yield loss in maize or sorghum was high in the samples were taken toward the canal than other were taken toward the road. Losses in maize yield were 19.4, 16.5, 12.4, 8.0, 0.0 and 0.0 % at the distances of 6, 12, 18, 24, 30 and 36 meters from the canal, respectively. While the losses in maize yield in similar distances but toward the road were 14.6, 12.4, 8.2, 0.0, 0.0 and 0.0%, respectively. Loss in sorghum yield gradually declined from the outer to the inner distances of the field, recording loss percentages of 14.5, 11.2, 10.0, 6.4, 0.0 and 0.0 from the canal and 12.5, 9.6, 5.8, 0.0, 0.0 and 0.0 from the road at 6. 12. 24, 30 and 36 meters, respectively. The mean of yield losses in maize from all samples of the tested distances toward the canal and the road were 9.50 and 5.86%, respectively. While the mean of yield losses in sorghum were 7.1 and 4.63% from the all tested distances toward the canal and the road, respectively.
Correlation between the distances from the canal or road and the maize or sorghum yield loss recorded negative and highly significant values
V: Damage to standing and lodging wheat plants caused by rodents in El-Edwa district during the year of 2005 :-
This experiment was conducted in two fields whereas the plants were standing in one and lodging in the other. The highest significant damage (8.4 %) was recorded with the lodging plants in contrast 4.0 % with standing plants in 12 April when the grains were in pasty stage.
Attack of rodents to wheat was gradually declined before and after the pasty stage. All damage percentages in different dates of sampling were lowest in standing field than in the other lodging field. Lowest damage 0.8 %
VI-Control of Rattus rattus alexandrinus in El-Minia new city:-
In this experiment Zinc phosphide, Racumin, Tomorin were evaluated against Rattus rattus aexandrinus in the physician buildings in El-Minia new city by estimation of mortality percentages every one day for Zinc phosphide and 3 days for other antiogulants of repeated exposure by using food consumption.
Zinc phosphide surpassed Racumin and Tomorin in killing Rattus r. alexandrinus. This rodenticide was faster, whereas the high reduction of density was observed within one day after application giving a mean value of 78.8 % reduction. The bait consumption disappeared in the 3rd day of application with zinc phosphate while with Racumin and Tomorin the bait consumption gradually reduced and the completely nonconsumption was attained after 18 and 21 days of application, respectively, More than 50% reduction in rat density was observed in the 6th and 12th days from application with Racumin and Tomorin, respectively.
The estimated LT50 (The time needed for reducing the density to 50% after repeated exposure to fixed concentration in the bait) was less than one day with zinc phosphide.The LT50 with Rocumin were 5.20 days with upper confidence limit (6.66) and lower than from (4.06) day the L.T.P line slope was heterogeneity with a value of 2.66± 0.39 . Tomorin came in last whereas the LT50 was 7.98 days with upper confidence limit (9.38) and lower than (6.79) and the L.T.P line slope was heterogeneity with a value of 2.35 ± 0.36.
The conclusion :-
1. The household rodents replaced the desert rodents in the new cities such as New Minia city.
2. The Nile grass rat (Arvicanthus niloticus) lives in the fields and does not enter the houses except for obtaining nourishment in the case of nourishment rarity in the field then depart the residence to the field.
3. The studied rodent species differed in their abundance periods were recorded with Rattus rattus, Four abundance periods were recorded with Rattus norvegicus and five abundance periods were recorded with Mus musculus. Abundance periods may be related to the nourishment availability, temperature and relative humidity.
4. Maize and sorghum field were found to be affected by rodents and the injuries caused by rodents concentrated in the field edges and this may be attributed to the multitude of burrows and nests in the field rims, so the rodent control operations must be concentrated in the field edges.
5. Maize was found to be more affected by rodents than sorghum. This may be attributed to high concentration of the botanical oils preferred by rodents.
6. Rodents preferred the lodging wheat plants that mad the ears of wheat available to rodents, so we can recommend the avoiding lodging of wheat Atems by avoiding the irrigation in wind.
7. Before reclaiming new lands for building or planting we must survey the rodent species in these lands for making control program against these pests.
8. Control experiment in the physician buildings in New Minia city indicated the surpassing of Zinc phosphide than Racumin and Tomorin in killing Rattus .ralexandrinus. This rodenticide was faster. So we can advice for using Zinc phosphide as faster rodenticide for reducing the population of this rat then using other rodenticides for stobling this reduction.