Iraqi Journal of Aquaculture

This study was carried out to look for the effect of each copper and zinc on survival of grass carp Ctenopharyngodon idella juvenile and to compare these effects with the combined effects of a mixture of both copper and zinc in same concentration (0.1, 0.5) ppm for 15 days. The results of the study revealed that there is mortality has increased among the juvenile of grass carp with increasing of concentration of the metals and with exposure of them to combination mixture .In addition the bioaccumulation and recovery of both metals were studied in gill, kidney, and muscle. It was reported that the highest bioaccumulation and recovery was in the gill, kidney and muscle respectively.

The out-of season induced spawning of the Cyprinus carpio was done during the period October 2009 to February 2010 (Autumn and Winter), in the hatchery of Marin Science Center. The brooders average weight was 1.700-4.000 kg for females and 1.500-1.800 kg for males. The brooders were acclimated on 22 °C, for a period of 10 days. The photoperiod was 12-14 hour/day. The results showed that in this regime only one female and 3males had positive reaction to the pituitary gland hormone injection. While 4 female were positive to the Ovaprim during the second regime, in which the brooders were acclimated for 25 days, with same temperature and photoperiod. It was seen that the thermal acclimation for a long period out-of season was better for the maturation and spawning, and the use of Ovaprim give more response than PG extract. The indoor rearing of the larvae gives average weight of 0.5 g after 6 weeks. These results means that we can produce the fry of common carp before one month prior to the usual spawning season, which will prolong the production season in Basra Province.

Taxonomic studies on freshwater fishes of Iraq were reviewed. Considerable differences in number of species that have been recorded in Iraqi freshwater were noticed, the number ranged from 44 to 70 species. The difference might be due to recording of synonyms or incorrect records. The continuous record of new species on various periods may have contributed to such variation. Thirty eight species, mainly cyprinids, fell into the disagreement category. A final list of the species which have received majority agreement was proposed with a total of 53 species and 12 families.

A total of 34 fishes, belonging to the yellow-finned sea bream Acanthopagrus latus were collected, in April 2008 from Khor Abdullah northwest Arabian Gulf, by using trawler net. Fishes were surveyed for parasites. The study revealed the presence of two species of parasites the first one is a monogenetic trematode, Polylabris mamaevi and the second is a digenetic trematode, Paradiscogaster farooqii. The detection of P. farooqii in the present study represents its first record in the fishes of the Iraq.

The present study was carried out from December 2007, during which to November 2008 more than 210 fish (Barbus barbulus) were caught and measured, including, 57 males, 64 females and 89 immature fishes. Maximum and minimum total lengths were 885 mm and 210 mm respectively. Maximum and minimum total weight was 8460 g and 99 g respectively. The length-weight relationship was Y=0.00002 L2.90 (n=57, R2=0.85) for males, Y=0.000002 L3.22 (n=64, R2=0.87) for females and Y=0.00005 L2.96 (n=210, R2 =0.90) for total fishes, these results showed isometric growth of the studied fish. The mean value of GonadoSomatic Index (GSI) for the male and female were 1.58 ± 0.41 and 1.85 ± 0.22 respectively. For both sexes, the highest GSI value was in March and the lowest in December. GSI and maturity stages indicated that spawning time was during March to April. The mean size at first sexual maturity (Lm) was 380-430 mm for males and 470-520 mm for females.