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1.
Environ Sci Pollut Res Int ; 27(18): 23015-23025, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32329003

ABSTRACT

This work aimed at using Little Egrets (Egretta garzetta), for the first time in Egypt, as a bioindicator of heavy metal contamination from three different Egyptian land use types (Qillin within Kafr El-Sheikh (S1, agricultural), Toukh within Qalyubia (S2, semi-rural area), and Abu Rawash within Giza (S3, urban)). Concentrations of aluminum (Al), barium (Ba), cobalt (Co), cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn) were analyzed in liver and kidney samples of twenty-six adult Little Egrets collected from the three localities during winter 2018. Moreover, the study calculated the Metal Pollution Index (MPI) to highlight the health of the surrounding environment using birds' internal organs as a mirror. Results revealed that, throughout the three sampling sites, the total metal concentrations in liver samples exceeded that of the kidney, indicating that the liver is the target organ of metal accumulation. The Little Egret's liver was found to be the best-recommended organ to use in future biomonitoring of Cu, Zn, Fe, Mn, and Ni, whereas Al, Co, Cr, Ba, Pb, and Cd can be monitored in the kidney. Cu and Pb were higher in the Little Egret's tissues collected from the agricultural site (S1), whereas Ba, Ni, and Fe were higher in the semi-rural site (S2), followed finally by Cd in the urbanized site (S3). The concentrations of trace elements reported in Little Egrets were within the known background level for water birds. However, alarming concentrations were found for Ni levels in liver (from Qillin and Toukh), as well as Pb and Cr levels in kidney samples (from the three localities). MPI of the eleven studied metals in both liver and kidney of the studied species decreased in the order Qillin (24.36) > Abu Rawash (17.98) > Toukh (3.90). In the three investigated localities, the overall calculated MPI values were higher than one, indicating that the ecosystem is polluted. The study suggested using Little Egrets as a bioindicator of metal contamination.


Subject(s)
Environmental Biomarkers , Metals, Heavy/analysis , Animals , Birds , Ecosystem , Egypt , Environmental Monitoring
2.
Parasitology ; 146(1): 50-73, 2019 01.
Article in English | MEDLINE | ID: mdl-29921333

ABSTRACT

The importance of parasites as a selective force in host evolution is a topic of current interest. However, short-term ecological studies of host-parasite systems, on which such studies are usually based, provide only snap-shots of what may be dynamic systems. We report here on four surveys, carried out over a period of 12 years, of helminths of spiny mice (Acomys dimidiatus), the numerically dominant rodents inhabiting dry montane wadis in the Sinai Peninsula. With host age (age-dependent effects on prevalence and abundance were prominent) and sex (female bias in abundance in helminth diversity and in several taxa including Cestoda) taken into consideration, we focus on the relative importance of temporal and spatial effects on helminth infracommunities. We show that site of capture is the major determinant of prevalence and abundance of species (and higher taxa) contributing to helminth community structure, the only exceptions being Streptopharaus spp. and Dentostomella kuntzi. We provide evidence that most (notably the Spiruroidea, Protospirura muricola, Mastophorus muris and Gongylonema aegypti, but with exceptions among the Oxyuroidae, e.g. Syphacia minuta), show elements of temporal-site stability, with a rank order of measures among sites remaining similar over successive surveys. Hence, there are some elements of predictability in these systems.


Subject(s)
Helminthiasis, Animal/epidemiology , Helminthiasis, Animal/parasitology , Murinae/parasitology , Rodent Diseases/epidemiology , Rodent Diseases/parasitology , Age Factors , Animals , Binomial Distribution , Egypt/epidemiology , Female , Male , Prevalence , Sex Factors , Spatial Analysis , Time Factors
3.
Exp Appl Acarol ; 72(4): 415-427, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28849399

ABSTRACT

Following the description of Babesia behnkei in the region of St. Katherine, Sinai, the present study was undertaken to determine the role of local tick species as vectors of piroplasms. First we assessed the local fauna of ticks, especially species occurring on rodents, camels and encountered in the environment, and then we compared genotypes of ticks from isolated wadis. Finally, we assessed the role of local tick species as potential vectors of Babesia spp. During our expedition to the Sinai Massif in a 4-week period in August-September 2012, 393 ticks were collected, including 235 adult questing ticks collected from the environment (ground level in the wadis) and 158 engorging ticks from camels and rodents. Amplification and sequencing of a 600 bp fragment of the conservative 18S rDNA and a 440 bp fragment of the more variable mitochondrial (mt) 16S rDNA were carried out to enable the identification of 54 ticks and to assess the genetic variability of ticks collected from two distant isolated wadis. The camel tick Hyalomma dromedarii constituted the majority (80-90%) of adult ticks collected from three wadis in the Sinai Mountains near St. Katherine. Among juvenile ticks collected from rodents, three genotypes were identified: H. dromedarii; Hyalomma sp. showing low homology with H. dromedarii, H. lusitanicum or H. aegyptium; and Rhipicephalus sp. A new genotype of Hyalomma was identified in an isolated montane valley, W. Gebal. Babesia/Theileria DNA was not detected in any of the ticks, which is likely due to the low infection rate in the limited number of ticks that were examined.


Subject(s)
Babesia/classification , Babesiosis/transmission , Ixodidae/classification , Ixodidae/genetics , Phylogeny , Animals , Camelus/parasitology , Egypt , RNA, Ribosomal, 16S/analysis , RNA, Ribosomal, 18S/analysis , Rodentia/parasitology
4.
Vector Borne Zoonotic Dis ; 17(7): 483-494, 2017 07.
Article in English | MEDLINE | ID: mdl-28541836

ABSTRACT

Bartonella spp. are parasites of mammalian erythrocytes and endothelial cells, transmitted by blood-feeding arthropod ectoparasites. Different species of rodents may constitute the main hosts of Bartonella, including several zoonotic species of Bartonella. The aim of this study was to identify and compare Bartonella species and genotypes isolated from rodent hosts from the South Sinai, Egypt. Prevalence of Bartonella infection was assessed in rodents (837 Acomys dimidiatus, 73 Acomys russatus, 111 Dipodillus dasyurus, and 65 Sekeetamys calurus) trapped in 2000, 2004, 2008, and 2012 in four dry montane wadis around St. Katherine town in the Sinai Mountains. Total DNA was extracted from blood samples, and PCR amplification and sequencing of the Bartonella-specific 860-bp gene fragment of rpoB and the 810-bp gene fragment of gltA were used for molecular and phylogenetic analyses. The overall prevalence of Bartonella in rodents was 7.2%. Prevalence differed between host species, being 30.6%, 10.8%, 9.6%, and 3.6% in D. dasyurus, S. calurus, A. russatus, and A. dimidiatus, respectively. The phylogenetic analyses of six samples of Bartonella (five from D. dasyurus and one from S. calurus) based on a fragment of the rpoB gene, revealed the existence of two distinct genetic groups (with 95-96% reciprocal sequence identity), clustering with several unidentified isolates obtained earlier from the same rodent species, and distant from species that have already been described (90-92% of sequence identity to the closest match from the GenBank reference database). Thus, molecular and phylogenetic analyses led to the description of two species: Candidatus Bartonella fadhilae n. sp. and Candidatus Bartonella sanaae n. sp. The identification of their vectors and the medical significance of these species need further investigation.


Subject(s)
Bartonella Infections/veterinary , Bartonella/classification , Gerbillinae/microbiology , Animals , Bartonella/genetics , Bartonella/isolation & purification , Bartonella Infections/epidemiology , Bartonella Infections/microbiology , DNA, Bacterial , Egypt/epidemiology , Genotype , Phylogeny
5.
Parasit Vectors ; 9: 195, 2016 Apr 08.
Article in English | MEDLINE | ID: mdl-27059180

ABSTRACT

BACKGROUND: Long-term field studies of parasite communities are rare but provide a powerful insight into the ecological processes shaping host-parasite interactions. The aim of our study was to monitor long-term trends in the haemoparasite communities of spiny mice (Acomys dimidiatus) and to identify the principal factors responsible for changes over a 12 year period. METHODS: To this end we sampled four semi-isolated populations of mice (n = 835) in 2000, 2004, 2008 and 2012 in four dry montane valleys (wadis) located in the Sinai Massif, Egypt. RESULTS: Overall 76.2 % of spiny mice carried at least one of the five haemoparasite genera (Babesia, Bartonella, Haemobartonella, Hepatozoon, Trypanosoma) recorded in the study. Prevalence of haemoparasites varied significantly between the sites with the highest overall prevalence in Wadi Tlah and the lowest in W. El Arbaein, and this changed significantly with time. In the first two surveys there was little change in prevalence, but by 2008, when the first signs of a deepening drought in the region had become apparent, prevalence began to drift downwards, and by 2012 prevalence had fallen to the lowest values recorded from all four sites over the entire 12-year period. The overall mean species richness was 1.2 ± 0.03, which peaked in 2004 and then dropped by more than 50 % by 2012. Species richness was highest among mice from Wadi Tlah and peaked in age class 2 mice (young adults). Site was the most significant factor affecting the prevalence of individual parasite species, with Trypanosoma acomys and Hepatozoon sp. occurring mainly in two wadis (W. Tlah & W. Gharaba). In four of the five genera recorded in the study we observed a significant drop in prevalence or/and abundance since 2004, the exception being Hepatozoon sp. CONCLUSIONS: During the 12-year-long period of study in the Sinai, we observed dynamic changes and possibly even cycles of prevalence and abundance of infections which differed depending on parasite species. Although the exact reasons cannot be identified at this time, we hypothesize that the effects of a 15-year-long scarcity of rainfall in the local environment and a fall in host densities over the period of study may have been responsible for a drop in transmission rates, possibly by a negative impact on vector survival.


Subject(s)
Apicomplexa/isolation & purification , Bacteremia/veterinary , Bacteria/isolation & purification , Kinetoplastida/isolation & purification , Murinae/parasitology , Parasitic Diseases/epidemiology , Animals , Apicomplexa/classification , Bacteremia/epidemiology , Bacteremia/microbiology , Bacteria/classification , Egypt/epidemiology , Kinetoplastida/classification , Parasitic Diseases/parasitology , Prevalence , Spatio-Temporal Analysis
6.
Parasit Vectors ; 7: 572, 2014 Dec 09.
Article in English | MEDLINE | ID: mdl-25487227

ABSTRACT

BACKGROUND: Although a number of new species of Babesia/Theileria have been described recently, there are still relatively few reports of species from Africa. In this study based on the evaluation of morphology and phylogenetic relationships, we describe a novel species from Wagner's gerbil, Babesia behnkei n. sp. METHODS: Rodents (n = 1021) were sampled in four montane valleys (wadies) in 2000, 2004, 2008 and 2012 in the Sinai Mountains, Egypt. The overall prevalence of Babesia spp. was highest in the Wagner's gerbil (Dipodillus dasyurus; 38.7%) in comparison to the prevalence in the spiny mice species, Acomys dimidiatus and A. russatus. Morphological investigations were conducted for the comparison of trophozoites of the novel species of Babesia with the B. microti King's 67 reference strain. Thirty-two isolates derived from D. dasyurus over a 9 year period (2004-2012) from two wadies (29 isolates from Wadi Gebel and 3 from Wadi El-Arbaein) were investigated by microscopic, molecular and phylogenetic analysis. A near-full-length sequence of the 18S rRNA gene and the second internal transcribed spacer (ITS2) region were amplified, sequenced and used for the construction of phylogenetic trees. RESULTS: A novel species of Babesia was identified in two isolated populations of D. dasyurus. Phylogenetic analysis of 18S rDNA and ITS2 sequences revealed that B. behnkei n. sp. is most closely related to B. lengau from cheetahs from South Africa and to Nearctic species found only in North America (the pathogenic B. duncani and B. conradae) and that it is more distant to the cosmopolitan rodent parasite B. microti. Trophozoites of B. behnkei were smaller and less polymorphic than trophozoites of B. microti. CONCLUSION: Babesia behnkei n. sp. is a novel species of the 'Duncani group' maintained in isolated populations of Dipodillus dasyurus occurring in the Sinai Mountains of Egypt.


Subject(s)
Babesia/classification , Babesiosis/parasitology , Gerbillinae , Rodent Diseases/parasitology , Animals , Babesia/isolation & purification , Babesiosis/epidemiology , DNA, Ribosomal Spacer/genetics , Egypt/epidemiology , Phylogeny , Rodent Diseases/epidemiology
7.
J Wildl Dis ; 47(4): 958-62, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22102666

ABSTRACT

Eastern spiny mice (Acomys dimidiatus; also known as Sinai spiny mice) have been extensively studied in terms of the influence of parasite load on population size and reproductive fitness. The physical isolation of these rodent populations makes them interesting models for disease interactions in a real-life population as opposed to a laboratory. We identify betaherpesvirus sequences in eastern spiny mice and Wagner's dipodils (Dipodillus dasyurus), species that inhabit dry montane wadis (dry creek valleys) of the Sinai, highlighting the need for a comprehensive analysis of the full pathogen repertoire of these rodents in long-term studies.


Subject(s)
Betaherpesvirinae/isolation & purification , Gerbillinae/virology , Herpesviridae Infections/veterinary , Murinae/virology , Rodent Diseases/virology , Amino Acid Sequence , Animals , DNA, Viral/analysis , Disease Reservoirs/veterinary , Disease Reservoirs/virology , Herpesviridae Infections/epidemiology , Herpesviridae Infections/virology , Molecular Sequence Data , Sequence Alignment
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