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Moina sp. recently has attracted the interest of hatchery operators because it is a renewable resource and has a low production cost. The effect of live and frozen forms of Moina in replacing Artemia during the larval rearing of river catfish, Pangasius nasutus, Bleeker, 1863, was investigated for 21 days. The eight-day-old posthatchling larvae were fed with live Moina (LM), frozen Moina (FM), and live Artemia (LA), of which LA served as control. The feeding trials were done in triplicate. There was no significant difference in the final mean weight and specific growth rate between all treatments. However, the larvae exhibited significantly (P <.05) higher survival when fed with LM (27.2 ± 1.1%) against LA (15.9 ± 3.9%) and FM (1.1 ± 0.7%). As a conclusion, live Moina could be used to replace Artemia in the larval rearing of P. nasutus based on comparable growth performance and improved survival. [ABSTRACT FROM AUTHOR]

Malaysian Mahseer (Tor spp.) is a highly priced native freshwater fish in Malaysia and much sought after as food, ornamental and recreational fish. However, the production of mahseer is still insignificant. Due to the decline in the wild stock population of mahseer, farmers are compelled to rely heavily on imported broodstock or hatchery-produced fingerlings. The R&D on mahseer is also limited with only several reports on breeding techniques, feed requirement and genetic distance between populations. The availability of superior breeding stocks, efficient hatcheries management and formulation of maturation diet that could expedite the maturation process could greatly assist in increasing mahseer aquaculture productivity. This paper presents the R&D carried out by the Fisheries Research Institute, Department of Fisheries Malaysia starting from the 11th Malaysia Plan (2016 to 2020), particularly on the broodstock development, breeding, disease, seed management, formulation and validation of maturation diet. In this programme, broodstocks obtained from five different states namely Pahang, Johor, Sarawak, Perak and Terengganu, Malaysia were used as a base population and mated using full diallel method to produce a total of 75 families. The maturation diet enhanced the breeding capacity and shortened the maturation period of mahseer from 3.0 years to only 1.8-2.0 years. Three innovations, hatching system, nursing system and maturation diet were produced from this programme were also registered innovations. This paper also deliberates the challenges faced in broodstock development programme and the way forward. [ABSTRACT FROM AUTHOR]

Pangasiids are an economically significant group of catfish, and many pangasiids are threatened in the wild from anthropogenic pressures, including increases in fishing pressure, habitat degradation, and improperly managed aquaculture practices. This study demonstrates the usage of DNA barcoding of the Cytochrome Oxidase subunit I (COI) gene as an identification tool in detecting potentially threatening invasive pangasiid species by establishing the diversity and phylogenetic relationship of Pangasiidae catfishes in Peninsular Malaysia. A neighbour-joining (NJ) dendrogram (Kimura-2-parameter model) generated five clades to represent distinct genera. Pangasius was further subdivided into two clades (Clade A: Pangasius bocourti-P. djambal and Clade B: P. nasutus-P. conchophilus). Given the marginal genetic divergence, indigenous and non-native species should be treated cautiously in allopatrically distributed species. The analysis used Automatic Barcode Gap Discovery (ABGD) and revealed barcode gaps between the intraspecific and interspecific distances. The sequences were partitioned into five groupings, corresponding with the species delineation based on the distribution of pairwise differences, which could not be differentiated using the NJ dendrogram. ABGD allows the recognition of one or two additional species using the recursive approach, but other taxonomic methods should be considered for a solid conclusion. DNA barcoding demonstrates the identification of closely related species, thus justifying its application towards the conservation of these fish. [ABSTRACT FROM AUTHOR]