Iraqi Journal of Aquaculture

The Groupers fishes consist many important marketable species, in the world and the Gulf region, but it's populations were gravely reduced. The production of Groupers was either by fisheries- based aquaculture, or by artificial breeding. The baby Groupers were caught during early summer from the costal waters, estuaries and tidal pools. The Groupers are mostly Protogynous hermaphrodites, and the hormones implantation were used for sex reverse. The enrichment of the brooders diet must be done with polyunsaturated fatty acids, that to amelioration the eggs quality and increasing larval quality and survival rate. The hormone injection was used either for artificial insemination or semi-natural breeding. The induced brooders were placed in spawning tanks, and then the floating fertilized eggs were collected by collecting funnel. The hatching troughs were used for hatching the fertilized eggs. The larvae could be produced in raceways, earthen ponds, and outside cement tanks. The live food must produce in the hatchery for the feeding of the newly hatching larvae. Then the fingerlings could be reared to marketing size for a period of 6-8 months.

The present study showed the effect of water currents (0.20 – 0.25 m\sec.) on the movement behaviour of Macrobrachium nipponense during 2 and 24 hour periods inclusive of weight group five (g) . In the first period, the results indicated that group one (0.10 – 0.49 g) aggregated towards the water currents or contrary currents by the relative percentage of 64.47 & 35.33 % , where as the groups were distributed in the following sequences : two , three and four 44 & 56 , 40.67 & 59.33 and 38 & 62 % , respectively . But the results of group five were 3.33 & 96.67 % . However, the results of the second period for the five groups were : 38 & 62 , 27.33 & 72.67 , 22 & 78 , 19.33 & 80.67 and 13.33 & 86.67 % , respectively . The distribution of these age-groups determined at different parts of the tank .

An experiments were conducted in open culture system to study the effect of food additives i.e. vitamin C and sodium bentonite to improve the diets characteristics of common carp Cyprinus carpio in concentrations 100, 250 and 500 mg vitamin C/ kg diet and 10, 20 and 30 gm S.B./ kg diet. The results indicate that there was a significant differences (P0.01) were noticed between diets in food in take which ranged between 2.62 to 3.43 % from body weight .The body protein levels were increased (16.36 – 21.00 %) compared to it level before experiments (15.59) .The diets contain all levels of vit.C and 20 gm of sodium bentonite showed high protein digestibility. The feces weight increased with vit.C level but decreased with sodium bentonite level. It was concluded from the present study that food additives are economically important to increase growth and food efficiency which in turn lowering fish production cost.

The aim of this study was to produce fish protein concentrate from marine fish Cynoglossus bilineatus, the fish brought from local Basrah market and dried in the oven at 025 °C for 06 h. The chemical composition of the dried fish were 48.62 % protein (N×6.25), 19.49 % fat and 19.95 % ash, while for the processed protein concentrate were 79.56 % protein (N×6.25), 6.38 % fat and 9.51 % ash. The obtain yield was 67.58 % of dried fish. The processed product characterized with light brown and acceptable fishy smell, and also showed good strong stability after 90 days of storage regarding to TVNB, TBA and total bacterial count at 28 °C, 10 °C and - 4 °C without objectionable changes in color and smell. The processed product also had low total bacterial count which was 487, 481 and 462 CFU/gm for the temperatures and storage time above respectively, as well as, coliform bacteria was not detected. The total volatile nitrogen bases were 8.4, 8.2 and 8.0 mg N/ 100 gm, while the TBA were 0.628, 0.266 and 0.263 mg malon aldehyd / kg for the same temperatures and storage time respectively.

The aim of the present study is to find out if the occurrence of the zooplankton with the incubated eggs of the common carp (Cyprinus carpio L.) could increase the fungal infection causing saprolegniasis in the main fish hatchery in Iraq during the artificial propagation from April to June 2009. Four eggs treatments were used, the highest hatching rate was 85.8 % in treatment no. 2 in which filtered water was used to incubate the eggs and lowest hatching rate was 21 % in the negative control according to the availability of zooplankton and the absence of fungicidal treatment. Crustacea identified were: Bosmonia, Cyclops, Daphnia, Moina, Nauplii and aquatic insects were: Chironomas, Notonicta, Culex.