ISSN: 1812-237X

Volume 3, Issue 1

Volume 3, Issue 1, Spring 2006, Page 1-73


INVASION OF ZEBRA MUSSEL DREISSENA POLYMORPHA( PALLAS,1771) INTO THE COOLING SYSTEM WATER SUPPLY OF AL-MUSAYAB THERMAL POWER PLANT / IRAQ

N.A. AL-NAKEEB; T.R. AL-RAWI; H.J.J. JAWEIR

Iraqi Journal of Aquaculture, Volume 3, Issue 1, Pages 1-9

Zebra mussels Dreissena polymorpha are tiny bivalve mollusca , invade water supply of cooling system unit in Al-Musayab power plant, 60 km south-west Baghdad and grow to dense clusters. Its ability to rapidly colonize intake structures, such as pipes and screens causing reduction in water pumping capabilities .Some biological aspects of zebra mussel Dreissena polymorpha have been studied and some physical & chemical parameters were examined as alimenting factors for the species Samples collecting was done monthly from two sites within the water system , the first was the traveling band screen (TBS ) and the other site was small canal collecting excess water passing from TBS .Biological studies revealed that the samples collected from the canal includes five size groups with average length of 5.7 ; 11.3 ; 16.7 ; 21.9 & 27.3 mm. In TBS , the individuals found all over the year with highest number of 135 individuals recorded in August . Individuals of a length of 11.3 & 16.7mm were the dominant.In general, from total number of 799 individuals collected from TBS, 388 individuals were of size of 11.3mm and 239 individual were of size 16.7mm while no large specimens of large size group of 27.3mm were recorded in TBS.To study the settlement rate of larvae, several concreat tiles of (25X25cm) were suspended at depths of 2,4& 6 m. in the sedimentation pond (12m depth). The number of juveniles were counted monthly . The result showed that there were two peaks of settlement , one in June and the other in September and October .Depth of 6m was the most suitable for settlement.The average length of settled juveniles ranged between 3.5-6.1mm. Water temperature in the site ranged between 11-32o C , Dissolved oxygen was 4.8-8.3ml/L . The highest value of turbidity was 49NTU.Ca++ was 68-136mg/l and Mg++ was 34-72mg/l

EFFECTS OF STARVATION ON THE PROXIMATE CHEMICAL COMPOSITION OF THE JUVENILES BUNNYI BARBUS SHARPEYI

Amel A.J. Mahdi

Iraqi Journal of Aquaculture, Volume 3, Issue 1, Pages 11-16

Juveniles bunnyi Barbus sharpeyi were subjected to starvation for a period of 11weeks, the proximate chemical analysis of body composition showed that the main effect of starvation was found on the depletion in lipid content, followed by gradual protein decreasing, coincided with an increase in both moisture and ash content. Muscle lipid was the more storage of reserve than that of viscera, that’s why the lost weight from muscles was more. This shows that energy utilized was derived from lipid catabolism in muscle more than viscera. Both condition factor (K) and viscera somatic index (VSI) tend to progressive decrease as starvation period proceded, and there was an inverse relationship between moisture and lipid content in whole specimen.

SAPROLEGNIASIS OF BARBUS SHARPEYI , GUNTHER (BUNNEI FISH) IN BASRAH / IRAQ

A.H. AL-DUBOON; MUKHTAR; M. A. AL; A.A.R. JASSIM; S.Q. BADER; J.M. AL-ZAWAR

Iraqi Journal of Aquaculture, Volume 3, Issue 1, Pages 25-29

Among 600 bunnei fishes transferred from Qurna marshes to fish ponds at Basrah University/Marine Science Center, 211 fishes were infected with saprolegniasis during the period from January to March, 2005 constituting a percentage of infection of 35.1% which was diagnosed by its clinical features and by direct examination with 10% KOH solution and by culture. The cultutred fungus was Saprolegnia parasitica.

STOCK ASSESSMENT OF COMMON CARP CYPRINUS CARPIO IN EUPHRATES RIVER, NEAR AL-MUSSAIB POWER STATION

A.R. M. Mohamed; A. J. Al-Rudainy; L. M. Abbas

Iraqi Journal of Aquaculture, Volume 3, Issue 1, Pages 31-41

The stock of common carp Cyprinus carpio in Euphrates river, near Al-Mussaib power station was studied from September 2002 to December 2003. A total of 766 specimens were collected, their total lengths ranged from 6.2 to 55.4cm and between 9-5500g in total weight. The catch rate was ranged between 8.4Kg/h in Summer to 30.2Kg/h in Spring. Length-weight relationship was W= 2.7 x 10-4 L 3.04. The lengths of fish were 23, 37, 48 and 54cm for the ages 1-4 years respectively. Growth and mortality parameters estimated were: L∞= 65cm, K= 0.26, Z= 1.02, M= 0.60 and F= 0.42. The exploitation rate (E) of carp was 0.41, lower than the optimum level. The values of Lc and Lm were 18cm and 27.1cm respectively and 55.3% of population was immature. A bimodal recruitment pattern of unequal strength was observed, the major contribution was 71.9% of the total recruits with a peak in May and the minor was contributed 28.1% with a peak in October.

CHANGES IN BLOOD PARAMETERS OF GRASS CARP CTENOPHARYNGODON IDELLA (VALENCIENNES, 1844) FINGERLINGS UNDER THE EFFECT OF CHLOROFETE

A. G. Y. AL-SAADI; T. S. Ali

Iraqi Journal of Aquaculture, Volume 3, Issue 1, Pages 43-55

The present study has carried out to clarify the changes of blood parameters of grass carp Ctenopharyngodon idella (Valenciennes, 1844), responding to chlorofete effect under laboratory conditions, in the presence and absence of aquatic plant Ceratophyllum demersum (L.). Three concentrations used during chronic exposure time extended to (15days). Blood tests of (R. B. Cs., Hb, P.C.V.) were studied for fish exposed to concentration investigated. The hematological parameters decreased with the increasing of pesticide concentrations. Moreover, values of indices (M.C.V.) showed significant increase with the increasing of pesticide concentration, particularly at highest concentration used (3.8) mg/l during (5, 6 and 9) days with absence aquatic plant. However, apparent increasing of (M.C.H.) were observed at especially at concentration of (3.8) mg/l during (6 and 9) days of exposure time. Significant increasing were recoded in (M.C.V.) values for treatment aquatic plant during (7 and 10) days at concentration (3.8) mgl and during (10) days for (M.C.H.). The present study showed non-significant reduction in (M.C.H.C.) values for both treatments with and without aquatic plant.

ANALYTICAL STUDY OF THE FISHERIES IN THE LOWER REACHES OF THE TIGRIS RIVER, NORTH QURNA, BASRAH, IRAQ

A.R. M. Mohamed; Saged S. Al-Noor; R. A.K. Faris

Iraqi Journal of Aquaculture, Volume 3, Issue 1, Pages 57-73

The fisheries of the lower reaches of Tigris river, north Qurna in Basrah Governorate have been analyzed during the period from January to December 2005. The fishing boats used there varied in lengths form 5 to 10m, of which 50% were motorized with 25-75 HP. Seine and drift gill nets are the main fishing gears used, their lengths ranged from 100 to 200m with mesh sizes of 14-100mm and 7-32mm for seine and gill nets respectively. The number of fishermen in each boat varied from 1 to 7. Twenty three fish species were recorded caught in the area, of which eight were marine species, belonging to twelve fish families, in addition to shrimps. The total catches ranged from 629Kg in January - march to 3335Kg in July- September with total catch of 7671Kg. Three species namely catfish Silurus triostegus, crucian carp Carassius carassius and khishni Liza abu comprised 86.93% of the total catches constituting 69.65%, 11.02% and 6.26%, respectively. The average catch per unit of effort was 19.8 Kg/hr/100m for seine nets and 2.42 Kg/hr/100m for gill nets. The diversity and evenness indices for biomass were 1.0 and 0.33, respectively, in July-September and 1.5 and 0.52, respectively, in October-December. The highest similarity index of species composition was between April-June and July-September (87%), and lowest between April-June and January-March (63%).