Ichthyofauna and some biological indices in Karoon, Dez and Bahmanshir Rivers (southwest of Iran)

During one year survey (1992-1993) 47 different species of fishes were caught by drift gill net from Bahmanshir, Karoon and Dez rivers. Distribution, frequency, ecological indices (diversity, richness and dominance), salinity coefficient (for Karoon and Bahmanshir rivers) were also calculated. In Karoon Rivers 32 species, in Bahmanshir 25 species and in Dez 12 species were identified. Freshwater fishes of Karoon include 17.9%, Bahmanshir 5.9% and Dez 14.6% of total freshwater fishes in Iran. Among identified fishes 4 nor endemic species, 2 anodermus species and the rest are dwelled and one species is rare. The most frequent species were: Clupeidae (3 genus and 3 species) in Bahmanshir river, and Cyprinidae (10 genus 16 species) in Dez river and (12 genus and 19 species) in Karoon river. Also the maximum fish abundance was in autumn, in Bahmanshir and Dez rivers and in spring in Karoon River. The similarity percentage of species between Karoon and Bahmanshir was very low. The maximum diversity and evens also belong to Bahmanshir and the maximum species richness and dominance belong to Karoon River

Molecular evaluation of the population of Silver Pomfret (Pampus argenteus) in the Persian Gulf and Oman Sea (Iranian &Kuwaiti waters)

A total of 162 specimens of Silver Pomfret (Pampus argenteus) including 38 samples from Kuwait and 124 samples from Iran (24 from Khouzestan, 24 from Chabahar and 38 from Bushehr) were examined for their DNA structure. DNA from all specimens was extracted using the Phenol-chloroform and amplified using PCR method with a pair of primers with ND sub(2) gene sequence. The PCR products were about 1300 (bp) for all samples. For RFLP analysis 16 restriction enzymes Bcl I, Pst I, Acc II, BseN I, Tru I, Dra I, Alw26 I, Hin6 I, Tas I, Alu I, EcoR I ,Hae III, Hinc II, Hind III, Hinf I and Hpa II were used. DNA bands were visualized by Gel electrophoresis (polyacrylamid) and staining with silver nitrate. Out of 16 enzymes, four showed polymorphism that includedg Hinf I, Alu I, Acc II, and Hpa II. Of the total 162 samples, 13 showed polymorphic patterns. Six haplotypes were rare occurring only once, but others which were only four different kinds occurred more than once. The REAP test gave no significant result for the examined regions (P>0.05). Therefore, our results revealed that the Pampus argenteus stocks in the Persian Gulf and Oman Sea of Iranian and Kuwaiti waters constitute a unique population

Reproduction and feeding biology of madagascar meager (Argyrosomus hololepidotus) from Khuzestan coastal waters

Biological attributes of Madagascar Meager (Argyrosomus hololepidotus) was studied from October 2008 to September 2009 in coastal waters of Khuzestan province. Average maximum length was 128.4±7.50 in October and average minimum length was 104.86±12.47 in May. The maximum weight was 27500g, the minimum weight was 5700g and mean weight for males and females were 15.222±4.40 and 16.942±5.09, respectively. Reproductive studies showed that peak maturity season occurred in July. The length­ weight relationship were calculated as W=0.042L 2 70 for males and W=0.06L2 61for females. The male-female sex ratio was calculated as 1:1.07 and chi-square analysis showed no significant difference (P>0.05) between the two sexes. The average absolute and relative fecundity were estimated to be 4054045±37265 and 179.19±50.41, respectively Madagascar Meager is carnivore and we found the diet of the species consisted of fish (75%), crustaceans (20%) and mollusks (5%). Analysis of monthly variation in the condition factor (CF) indicated a fluctuation throughout the year, with a high level during May. Vacuity index indicated a higher feeding rate in males compared to females. We also found that the species continues feeding in the spawning season