The relationship between pollution levels in river sediment and fluctuating asymmetry of resident silurid fish species,
Thirteen morphometric characters of catfish
Variation in the numbers of pectoral fin spines and rays, pelvic fin rays, gill rakers on the first gill arch, anal fin rays, and the number of vertebrae of Silurus triostegus Heckel were examined in specimens from 16 localities that span its entire distribution range in the Tigris, Euphrates, and Shatt al-Arab rivers in Iraq. The mean number of the six meristic traits increases toward high latitudes with maximum and minimum values in the north and south of Iraq. Based on cluster analysis and PCA, the Mesopotamian river samples were clearly separated into three distinct groups. The upper Tigris populations were isolated from those of the middle and southern populations of this river and from those of
This study was achieved to investigate the accumulation of some heavy metals included: Cadmium, Lead and Nickel in the tissues (gill, intestine, liver, muscles and skin) of Silurus triostegus Heckel, 1843 (Siluriformes, Siluridae) and its larval stage of the nematode Contracaecum sp. (Rhabditida, Anisakidae). As well as to assess the infection patterns of Contracaecum among S. triostegus specimens which were purchased fresh from the local market in Baghdad. One hundred and nine nematodes specimens in larval stage were recovered from the fish host; the overall prevalence of Contracaecum sp. was 38.6%. The sex of the host was not significantly (P ˃ 0.05) associated with the infection of this nematode. Results showed that the ov
... Show MoreThis study was achieved to investigate the accumulation of some heavy metals included: Cadmium, Lead and Nickel in the tissues (gill, intestine, liver, muscles and skin) of Silurus triostegus Heckel, 1843 (Siluriformes, Siluridae) and its larval stage of the nematode Contracaecum sp. (Rhabditida, Anisakidae). As well as to assess the infection patterns of Contracaecum among S. triostegus specimens which were purchased fresh from the local market in Baghdad. One hundred and nine nematodes specimens in larval stage were recovered from the fish host; the overall prevalence of Contracaecum sp. was 38.6%. The sex of the host was not significantly (P ˃ 0.05) associated with the infection of this nematode.
Results showed that the overall me
Concentrations of heavy metals (Copper Cu, Iron Fe, Manganese Mn, Cadmium Cd, and Lead Pb) have been studied in river crab Sesarma boulengeri (Outer part of the shield and interior tissues) which caught from two stations in Shatt Al – Arab river (Salhia and Aldeir areas). Elements concentrations were measured by Flame Atomic Absorption Spectrophotometer, concentration of heavy metals in the internal tissues was higher than in the outer shield in both of the stations with the highest value of the elements was to iron 95.21 mg\ kg during the spring as well as copper was 55 mg\kg and manganese was 39.09 mg\kg. The study showed the presence of seasonal changes in the studied heavy metals concentrations values in the tissues of river crab;
... Show MoreFor the first time in Iraq, this study presented a putj;uance to ti the
main embryological development phases of the Asian catfish Silurus
triostegus .Embryological morphological illustrations and behaviour remark have been given.
It was found that eggs of this species are of Telolecithal type. Two hours after fertilization of the fi rst cleavage took place , it became
taster until the 64 cells stage, af\erward slowed down . In 4 hours the eggs reached the morula stage while gastrula stage achieved within 9 hours.
Separation of head and tail commence at 25 hours . First, heart
pulssing was observed at 35 hourswhile blood flow started 8 hours later .
Chromatop
... Show MoreA total of 109 fish specimens belonging to six species (Barbus grypus, B. luteus, B. xanthopterus, Cyprinion macrostomum, Cyprinus carpio and Liza abu) were collected from Tigris river passing through Salah Al-Deen province during the period from September 2008 till January 2009. These fishes were infected with nine parasite species which included two sporozoans (Myxobolus mülleri and Dermocystidium percae), three ciliates (Trichodina cottidarum, T. elegini and T. murmanica) and four monogenetic trematodes (Dactylogyrus rhodeianus, D. vastator, Paradiplozoon cyprini and Microcotyle donavini). Among these parasites, two trichodinids (T. elegini and T. murmanica) were reported for the first time from fishes of Iraq. Also, B. grypus is c
... Show MoreThe root lesion nematode, Pratylenchus neglectus, is one of the most damaging nematodes to affect wheat worldwide. The nematode is widely distributed in Montana, primarily affecting winter wheat within the state. Managing the nematode primarily involves rotation to resistant and moderately resistant crops (peas, lentils, and barley). A nematode survey was conducted across the state nearly 10 years after an initial survey, to reassess the nematode threat and assess the impact of changing trends in crop rotations. To assess the broad applicability of rotation crops to control P. neglectus across Montana, greenhouse trials were conducted to challenge rotational crops using eight populations of P. neglectus collected from geographicall
... Show MoreThe mineralogical investigation, geochemical analysis, and grain size calculation were carried out for floodplain sediment in the Tigris River to identify the properties of the sediment. The average values of the three main sediment classes, very fine sand, silt, and clay are 9.67, 62.53 and 27.80%, respectively. The silt size fraction was predominant. The classification and nomenclature of surface sediment types from the floodplain of the Tigris River are sandy-silt and mud, and they are the dominant sediment. Statistical parameters of grain size analysis refer to the average of the median values 3.74 Φ very fine sand; mean in average 6.16 Φ coarse silt; standard deviation evident by average 1.30 Φ poorly sorted, skewed; in
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