Basrah Journal of Agricultural Sciences

The stock of Otolithes ruber in north-west Arabian Gulf was studied from March 2004 to July 2005. A total of 4790 specimens of O. ruber were collected, their lengths ranged from 7 to 64cm. Length-weight relationship was obtained as W= 0.0101 L^ 3.090. The relative condition factor ranged from 0.9 in June to 1.06 in February. The fish stock was assessed using FiSAT program. Growth and mortality parameters estimated were L∞= 71.96cm, K= 0.28, Z= 0.91, M= 0.58 and F= 0.33. The current exploitation rate (0.36) of O. ruber was lower than the optimum level (E0.5= 0.27). A bimodal recruitment pattern of unequal strength was observed. The maximum yield per recruitment could achieved at Emax= 0.44.

Stock of Pseudorhombuss arsius in north-west Arabian Gulf was studied from March 2004 to July 2005. A total of 6772 specimens of P. arsius were collected, their lengths ranged from 8 to 33cm. Length-weight relationship was obtained as W = 0.0271 L 3.0011. Relative condition factor ranged from 0.97 in June to 1.05 in March. The fish stock was assessed using FiSAT program. Growth and mortality parameters estimated were: L∞= 40.1 cm, K= 0.59, Z= 2.3, M= 1.2 and F= 1.1. Current exploitation rate (0.48) of P. arsius was slightly lower than the optimum level. A bimodal recruitment pattern of unequal strength was observed. Maximum yield per recruitment could achieved at Emax= 0.52.

The study included the morphological desicription of species of the family Ergasilidae which include the genera Ergasilus, Dermoergasilus, Paraergasilus and Mugilicola. Sample were examined in 85% lactic acid, Drawings were done using wooden slide method with the aid of a camera lucida fixed on compound microscope.
Description included the morphology of the cephalothorax, abdomen, second antenna and egg sacs M. kabatai was simply identified from members of the other genera, because its body consists of three major parts, i.e head, neck and trunk, while P. inflatus was identified from its second antenna which tipped with three strongly curved clasws. The second antenna of Dermoergasilus varicoleus developed a cuticular membrane, morover the three segments of the abdomen were distinctly elongated. Cephalothorax of the members of the genus Ergasilus showed different shapes (ovoid, elongated or guitar shape). Egg sacs varied in shape and length according to the length of parasite body.

Morphology, age and growth of Barbus luteus (Heckel, 1843) in Al-Suwaib marsh, south Iraq, were studied from December 2004 to November 2005. A total of 547 B. luteus (78-293mm TL) were collected using gill nets of different mesh sizes and electrical fishing.
Twenty one morphometric and seven meristic characters were described. The morphometric characters were calculated as numerical ratio to standard and head lengths. Fish of 140-190mm length groups of B. luteus were dominants in the samples. Total length–weight relationship of B. luteus was W= 1.32 × 10-5 L 3.0074. The mean relative condition factor was 1.003.
The annuli on scales formed during December and the growth of the scales were high during the period from February to August and were associated with water temperatures. The relation between standard length (L) and scale radius (S) was: L = 7.287 + 4.358 S. The age composition was ranged from 1 to 7. The standard lengths for these ages were 97.1, 123.7, 150.6, 174.1, 200.5 and 235mm respectively. The growth of B. luteus was within the growth of other Iraqi waters. The von Bertalanffy growth model was Lt = 350 (1-e -0.131 (t+ 0.374)).

Yellow fin seabream Acanthopagrus latus (Houttuyu, 1782) collected from Shatt al-Arab river, Shatt al-Basrah Canal and Iraqi marine water, North West Arabian Gulf were classified depending on the morphometric and merstic characters. Samples were obtained from December 2006 to October 2007. Twenty two morphometric characters and twelve characters for the species were described. The morphometric characters were calculated as numerical ratio to standard and head lengths and the relationships between the standard length and other morphometric characters were calculated. The indices characters associated with standard length varied from 0.79 of fork length in Shatt al-Arab to 17.54 of snout length in Iraqi marine water. While indices of characters associated head length ranged from 0.93 of head depth in Shatt Al-Arab to 5.95 of snout length in marine water. The slopes of the regression line between the standard length and the morphometric measurements ranged from 0.026 of eye diameter in marine water to 1.084 of total length in Shatt Al-Arab. The lowest values of correlation coefficient were observed between the standard length and eye diameter (0.75) and between the head length and eye diameter 0.83 in Shatt Al-Arab. No significant variations in merstic characters of fish between the three regions. The low values of the coefficient of variation (CV%) for characters (<10) may indicate little influence of environmental variation on morphometric variability. The morphometric and merstic characters showed that the A. latus in Shatt Al-Arab river, Shatt Al-Basrah Canal and Iraqi marine water considered as one group no more.

Biometry characters of genus Carassius from Qarmat Ali river southern
Iraq were studied, the results showed that all specimens belong to gold fish
Carassius auratus (Linnaeus, 1758). Number of scales in the lateral line
ranged from 25 to 31. Number of dorsal branched rays varied from 15 to
18, anal fin with 5-6 branched rays usually 5. Gill rakers long varied from
45 to 48. Total vertebrae 28-30. Pharyngeal teeth were in one row 4-4.
Body ratios of fishes were calculated, its means ranged from 0.99 of
CPL/CPD to 3.47 of HL/ED, while was 2.41 of SL/BD.