The monogenean Gyrodactylus lavareti Malmberg, 1957 is recorded here in the present study for the first time in Iraq from gills of the common carp Cyprinus carpio. This is the twentieth gyrodactylid species to be recorded from fishes of Iraq. The description and measurements of this parasite as well as its illustration were given.   
 

First record of Myxobolus insignis Eiras, Malta, Varella, Pavanelli, 2005 (Myxozoa: Myxobolidae) in Iraq from gills of the common carp Cyprinus carpio

The monogenean Gyrodactylus taimeni Ergens, 1971 was recorded in this study for the first time in Iraq from gills of the common carp Cyprinus carpio Linnaeus, 1758. The description and measurements of this parasite as well as illustration were given. In addition, a list of species of Gyrodactylus so far recorded from C. carpio in Iraq is also included together with a list of all other hosts recorded for each gyrodactylid species.

The present study attempts to identify some of the differences between the skull bones of two species Cyprinus carpio and Carassius carassius, which belong to the Cyprinidae family. The study is a taxonomic diagnostic study between the two species which are considered local fish abundant in the Iraqi aquatic environment

    The monogeneans Gyrodactylus dzhalilovi Ergens & Ashurova, 1984, G. magnus Konovalov, 1967 and G. matovi Ergens & Kakachava-Avramova, 1966 were recorded in this study for the first time in Iraq from gills of the common carp Cyprinus carpio Linnaeus, 1758 collected from Tigris River in Baghdad city. The description, measurements and illustrations of these parasites were given.

    The examination of gills of the common carp Cyprinus carpio revealed the presence of two species of the family Trichodinidae belonging to the genus Dipartiella (Raabe, 1959) Stein, 1961 namely D. indiana Saha and Bandyopadhyay, 2017 and D. kazubski Mitra and Bandyopadhyay, 2009 for the first time in Iraq from Al-Graiat location on the Tigris River at Baghdad city. This also represents the first record of the genus Dipartiella from fishes of Iraq. The descriptions and measurements of these two parasite species as well as their illustrations were given.

In fish, a complex set of mechanisms deal with environmental stresses including hypoxia. In order to probe the hypothesis that hypoxia-induced stress could be manifested in varieties of pathways, a model species, mirror carp (Cyprinus carpio), were chronically exposed to hypoxic condition (dissolved oxygen level: 1.80±0.6mg/l) for 21 days and subsequently allowed to recover under normoxic condition (dissolved oxygen level: 8.2±0.5mg/l) for 7 days. At the end of these exposure periods, an integrated approach was applied to evaluate several endpoints at different levels of biological organisation. These included determination of (i) oxidative damage to DNA in erythrocytes (using modified comet assay), (ii) lipid peroxidation in liver sample

L-arabinose isomerase from Escherichia coli O157:H7 Was immobilized with activated Bentonite from local markets of Baghdad, Iraq by 10% 3-APTES and treated with 10% aqueous glutaraldehyde, the results refer that the yield of immobilization was 89%, and pH profile of free and immobilized L-arabinose isomerase was 7 and 7.5 and it is stable at 6-8 for 60 min respectively, while, the optimum temperature was 30 and 35°C and it was stable at 35 and 40°C for 60 min but it loses more than 60 and 30% from its original activity at 50°C for free and immobilized L-arabinose isomerase respectively. Immobilized enzyme retained its full activity for 32 day, but it retained 73.58% of its original activity after storage for 60 d