Monthly carapace length frequency data of green tiger prawn, Penaeus semisulcatus were collected from the coastal waters of Bushehr, Persian Gulf, from January 2002 to March 2003. ELEFAN in the software package FiSAT was used to analyse of their length frequency data. The L ∞ and K for males were estimated at 38 mm CL and 1.6 year −1 , respectively and for the females 50.40 mm CL and 2.20 year −1 . Using the L ∞ and K estimates for both sexes and average water temperature of 24.1 • C the instantaneous rate of natural mortality (M) for males and females were calculated as 2.11 and 2.41 year −1 , respectively. The instantaneous rates of total mortalities (Z) were estimated from length-converted catch curves and the values at 6.4 year −1 for males and 8.2 year −1 for females, and the instantaneous rates of fishing mortalities (F) for males were 4.3 year −1 and for females 5.8 year −1 . Thus, the exploitation rates (E) were 0.67 year −1 and 0.7 year −1 for males and females, respectively. Maximum age (T max ) was 20 months for the males and 15 months for the females. Based on the results of the present study, P. semisulcatus growth is rapid during summer and autumn and negligible during winter and spring. Natural mortality rates were not grossly different for both sexes, although the males were more vulnerable to fishing than the females. Also the results showed that P. semisulcatus was overexploited in the study area. The exploitation of P. semisulcatus in Bushehr waters is intended to protect the spawners and juveniles stock for renewal.

Annual gonad hormonal profile of wild, matured mahseer (29 males and 23 female) averaging in weight between 0.95±0.26 and 1.19±0.23 kg for males and females, respectively, were investigated from November 2007 to November 2008 using enzyme-linked immunosorbent assay (ELISA) technique. Blood was collected from caudal vein, monthly and plasma separation by centrifugation was done to measure reproductive hormones: 17β-estradiol (E(2)), testosterone (T), and 11-keto-testosterone (11KT). Gonads were sampled for histology processing to observe their maturity. Highest T level in females and males was recorded at 0.22±0.016 and 0.88±0.014 ng/ml, respectively. The 11KT showed several peaks and the highest value was noted at 0.7±0.018 ng/ml in November 2008. The female E(2) initially was at 1.48±0.16 ng/ml and significantly increased (P<0.05) to 1.53±0.39 ng/ml in November 2008. Ovaries were laden with oocytes in several stages in all the samples while testes gonad showed a high level of spermatids throughout the year. Changes in plasma level of the gonadal hormones were correlated with the ovarian and testes maturities. In conclusion, the study suggests that mahseer can be categorized as asynchronized and multiple spawner. The information gathered is important for appropriate breeding and conservation programs of the Malaysian mahseer.

Eurycoma longifolia Jack is well known among the communities in Southeast Asia because of its aphrodisiac properties and its effectiveness as the cytotoxic, anti-malarial, anti-ulcer, anti-tumor promoting and anti-parasitic agent. Micropropagation through direct plant regeneration from in vivo shoot tip explants was carried out. The highest regeneration percentage (90%) and multiple shoots formation were obtained with the basal Murashige and Skoog (MS) medium supplemented with 5.0 mg l Ϫ1 kinetin. Roots were induced after 14 days of culture in the basal MS medium supplemented with 0.5 mg l Ϫ1 of indole-3-butyric acid. Plantlets regenerated from shoot tip explants survived well with no morphological differences from parent plants after two months of transplantation to soil.

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This study analysed morphology and histology of the developing mouth and digestive tract of the Malaysian mahseer larvae to assess the best weaning time to a compound diet for the fry on the basis of their morphological features. The mouth development was monitored using light and scanning electron microscopy; the development of the alimentary canal was followed histologically using light microscopy after haematoxylin-eosin staining. The larval mouth opened 1 day after hatching (1 DAH); the histological structures of oesophagus were completed by 5 DAH. At 2 DAH, differentiation of enterocytes began, and at 7 DAH the supranuclear protein inclusion appeared in the posterior intestine. The hepatopancreas was structurally completed at 4-5 DAH, coinciding with the start of exogenous feeding and the evidence of lipid storage in the liver. It was concluded that Malaysian mahseer larvae should certainly be able to ingest, and possibly digest and absorb, a formulated diet of 287 lm Ø from 7 DAH onward.