Asymmetry analysis has been carried out for some bilateral characters of Decapterus russelli (Family: Carangidae) collected from Oman Sea. The results showed that postorbital length demonstrated the highest incidence of asymmetry among the characters studied. The lowest asymmetry value was for the number of pectoral fin rays. An increasing trend in the asymmetry value with fish length is also obtained for preorbital length, number of pectoral fins and number of lateral line scutes. A similar trend is also evident in the postorbital length and eye lens diameter of individuals with body sizes <160 mm. The possible causes of asymmetry in this species are herein discussed in relation to different pollutants and their presence in the area.

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The present study was conducted to determine the adverse effects of high incubation temperature on growth, development and genome stability of broiler chick embryo in ovo). One hundred twenty broiler eggs from Cobb Company, USA were weighted and divided into two groups. The first group was incubated at 37oC ± 0.5oC, and the second group was incubated at 41oC ± 0.5oC from 0 to 18th day. Starting on day 4th and every other day; three eggs from each group were examined following performed measurements as weight of eggs post incubation, embryo, yolk, and egg shell for measuring growth index. Blood smear was also prepared for counting heterophiles, and lymphocytes to determine H/L ratio. Micronucleus formation and presence of binucleated red blood cells were investigated as genome stability parameters, in 2000 cells. Significant reduction (P<0.01) in growth indices was observed in embryos grown at 41oC compared to those grown at 37oC ± 0.5oC. Reduction in H/L ratio was statistically significant (p≤0.01) in embryos of 2nd group comparing to 1st group embryos. Blood of embryo from heat stress group group (2) showed Red blood cells with micronuclei and binucleated cells while no such phenomenon could be seen in embryos from control group group (1). These results suggested that heat stress is influencing cell division at telophase and induces chromosomal damage. 88% of chicks from group (1) were hatched on day 21st; only 18% of chicks from group (2) were hatched lately on day 23rd, while the others were found dead. These results indicate that heat stress not only adversely affects growth and development of embryo stem cells but also induces genome instability which intern resulted in poultry production losses.

The current study focused on assessing the presence/absence of cysts of some harmful algal species in Sohar Industrial Port (SIP) and in the seawater intake basin of the desalination plant located in the Sea of Oman. A total of seven type's species of potential harmful dinoflagellate cysts species were identified inside Sohar Port and in its surrounding area, while no cysts were found in the intake area of the desalination plant. The presence of cysts-forming algae in the port and their absence from the intake site of the desalination plant indicates that the port is providing a suitable environment for their survival. M. polykrikoides cysts were found during the two periods of sampling indicating their establishment of population and may well pose serious threat to the desalination plant in the future.