Molecular Phylogenetics and Population Structure of two Mahseer Species (Tor Tambroides Bleeker and Tor Douronensis Valenciennes: Cyprinidae) in Malaysia

This study examines the phylogenetic relationships of mahseer (genus Tor and Neolisssochillus) and their relationships with other selected cyprinids using sequence analysis of mitochondrial DNA cytochrome c oxidase I (COI) gene (464 base pairs). This study also describes the genetic structure of Tor tambroides and Tor douronensis, two important mahseer in Malaysia using both mitochondrial COI sequences and nuclear microsatellites DNA. The findings of the phylogenetic study strongly support the reciprocally monophyletic status between genus Tor (T. douronensis and T. tambroides) and genus Neolissochillus (represented by Neolissochillus stracheyi.) thus, strengthen the taxonomic status for all the three indigenous mahseer. For the other indigenous cyprinids, an interesting finding was that Barbonymus gonionotus was phylogenetically distinct from its morphologically similar species, Barbonymus schwanenfeldii (K2P distance value = 15.1%), and did not group together in a single Barbonymus clade. The population structure analysis inferred from mitochondrial COI sequences found high levels of intra and inter-population variations in T. douronensis. The presence of fixed haplotype differences among the populations, along with high FST values indicated that there has been little or no migration occur among the extant populations separated by large geographic distances, or river systems. For T. tambroides, low level of mitochondrial variations was found among the populations. The reason is probably due to the high proportion of the HKE1 haplotype found in most populations (0.736-1.000) studied except from Endau-Rompin (HKE4 is the dominant haplotype), or by the small number of samples used in the present study

A review of production protocols used in producing economically viable monosex tilapia

In the culture of tilapia seed various issues come into play tilapia when stocked in pond multiply excessively resulting in unhealthy competition for food and natural resources leading to a large number of stunted growths and a large number of mini fish that is not economically viable sexual diamophisim which means that the male fish grow bigger than the female in a mixed culture production, this results in culturists wanting only the seed of the male fish or ways that the sex of fish seed produced is skewed towards masculine fish. Culturist and farmers acknowledged the use of single sex fish also known as monosex fish as solution to the problem. The production of single sex fish which in the case of tilapia all male fish also has its own setback based on the production methods used in this case farmers ability to use the available resources in achieving the basic aim of production is a necessity. Monosex fish has the ability to tolerate sever environmental conditions including temperature, salinity low dissolve oxygen, greater uniformity of size is achieved at harvest because none of the fish is wasting energy in gonadal development. The various method used in producing monosex is based on the ability of the culturist to manage the structures (Pond, tanks) consumables (Hormones), systems (Water re-use, stagnant water) and skilled personal in producing and managing the production processes. In every step of production care is required because the production is gender specific pure breed most be used and strain confirm using current method of identification. INTRODUCTION The life history of the fish tilapia is made up of two distinct ability: Reproduction in captivity a virtue that has a positive and negative aspect (Nwachi, 2013). This characteristics of tilapia makes it a fish, farmers want to culture because of the fact that there will not be need for them to continually go back to procure fish seed after each circle of production at the same time this ability also results in production issue during culture. Tilapia, when stocked in pond multiply excessively resulting in unhealthy competition for food and natural resources leading to a large number of stunted growths and a large number of mini fish that is not economically viable (Campos-Mendoza et al., 2004), sexual diamophisim which means that the male fish grow bigger than the female, this results in culturists wanting only the seed of the male fish or ways that the sex of fish seed produced is skewed towards masculine fish. Monosex fish has the ability to tolerat

Comparative growth and survival of diploid and triploid mozambique tilapia (Oreochromis mossambicus) reared in indoor tanks

In the present study, the effect of cold shock on fertilized eggs of Oreochromis mossambicus was during triploid production. Two males (150 ? 224 g) and six gravid females (150 g to 264 g) were collected. The females were injected with ovulin at a dosage rate of 0.5ml kg(-1), the eggs were stripped into a dry bowl, fertilised with milt, divided into two groups (A and B) and incubated. After three minutes, group A was cold shocked at 50C for a period for 5 min, while group B was incubated normally. Tilapia larvae hatchlings were triplicated and stocked at a density of 200 larvae / liter in the aquaria for four weeks. Results showed that triploid fish had a lower hatchability (58%) and survival rate (47%) than diploid fish (of 85 and 70%, respectively), but a higher specific growth rate of 1.097 as compared to diploid at 0.931. While the improved growth rates have great commercial applications. Further research should be conducted to improve the lower hatchability and survivability of triploid tilapia

Molecular phylogeny of some Malaysian groupers (subfamily: Epinephelinae, family: serranidae) inferred from mitochondrial and nuclear gene sequences

Groupers are known as one of the important marine and estuarine fishes they are widely distributed in the tropical and subtropical open water. Nevertheless, the taxonomy and phylogenetic relationships among wild groupers in Malaysian waters are still poorly studied and need to be further clarified. Thus, this study aimed to elucidate the phylogenetic relationship of wild grouper using samples collected from eight coastal areas in Peninsular Malaysia. Samples were identified manually based on their morphological characteristics. Molecular phylogeny was inferred for subfamily Epinephelinae using a combined analysis of the mitochondrial cytochrome b and nuclear Recombination activating gene-1 (RAG-1) genes from 12 species representing three genera of subfamily Epinephelinae. Results from all methods of analyses (Neighbour-joining (NJ), maximum parsimony (MP), maximum likelihood (ML), minimum evolution (ME), and Bayesian analyses (BI)) produced similar tree topologies and strong supported the monophyletic status of the three genera within the subfamily Epinephelinae with genus Plectropomus was basal to the other genera. Phylogenetic analyses also divided genus Epinephelus into two different clades similar to other previous findings. Nevertheless, several relationships remain unresolved particularly among morphologically similar species (e.g between E. fario and E. longispinis) and species with limited number of individuals (E. coioides). Overall, the findings of this study have managed to provide new insights on the taxonomy, phylogeny and genetic diversity of grouper fishes in Peninsular Malaysia, which are important for their appropriate sustainable management, either for conservation or aquaculture purposes

Comparative growth and survival of diploid and triploid of mozambique tilapia (oreochromis mossambicus) reared in indoor tanks

In the present study, the effect of cold shock on fertilized eggs of Oreochromis mossambicus was during triploid production. Two males (150? 224g) and six gravid females (150 g to 264g) were collected. The females were injected with ovulin at a dosage rate of 0.5ml kg (-1), the eggs were stripped into a dry bowl, fertilised with milt, divided into two groups (A and B) and incubated. After three minutes, group A was cold shocked at 50C for a period for 5 min, while group B was incubated normally. Tilapia larvae hatchlings were triplicated and stocked at a density of 200 larvae / liter in the aquaria for four weeks. Results showed that triploid fish had a lower hatchability (58%) and survival rate (47%) than diploid fish (of 85 and 70%, respectively), but a higher specific growth rate of 1.097 as compared to diploid at 0.931. While the improved growth rates have great commercial applications. Further research should be conducted to improve the lower hatchability and survivability of triploid tilapia

Genetic structure and preliminary findings of cryptic diversity of the Malaysian mahseer (Tor tambroides Valenciennes: Cyprinidae) inferred from mitochondrial DNA and microsatellite analyses

This study examines the population genetic structure of Tor tambroides, an important freshwater fish species in Malaysia, using fifteen polymorphic microsatellite loci and sequencing of 464 base pairs of the mitochondrial cytochrome c oxidase I (COI) gene. A total of 152 mahseer samples were collected from eight populations throughout the Malaysia river system. Microsatellites results found high levels of intrapopulation variations, but mitochondrial COI results found high levels of interpopulations differentiation. The possible reasons for their discrepancies might be the varying influence of genetic drift on each marker or the small sample sizes used in most of the populations. The Kelantan population showed very low levels of genetic variations using both mitochondrial and microsatellite analyses. Phylogenetic analysis of the COI gene found a unique haplotype (ER8*), possibly representing a cryptic lineage of T. douronensis, from the Endau-Rompin population. Nevertheless, the inclusion of nuclear microsatellite analyses could not fully resolve the genetic identity of haplotype ER8* in the present study. Overall, the findings showed a serious need for more comprehensive and larger scale samplings, especially in remote river systems, in combination with molecular analyses using multiple markers, in order to discover more cryptic lineages or undescribed “genetic species” of mahseer

Mitochondrial DNA diversity of Tar douronensis valenciennes(Cyprinidae in Malaysian Borneo.

This study examines the population structure and taxonomy of Tor douronensis, an important indigenous freshwater fish species in Malaysian Borneo, by using sequence analysis of 466 base pairs of the mitochondrial cytochrome c oxidase I (COl) gene. A total of 62 fish samples were collected from five locations in Sarawak (N=54) and Sabah (N=8). The phylogenetic analysis using the Neighbour Joining (N]) method supported the monophyletic status between T. douronensis and Tor tambroides, which further reinforced their taxonomic status as distinct species. The T. douronensis haplo types were further divided into three major groups, with the Pelianuh from Sabah forming its own group (Cluster Ill) with strong bootstrap support. The large genetic differences separating the Sabah haplotypes from its Sarawak congeners suggested that the Pelian fish might represent a cryptic species. The current study showed high levels of intra and inter-population variations in T. douronensis. Within all population variations, T. douronensis populations were found, except in Bario. The presence offixed haplotype differences along with high FST values among the populations of T. douronensis, support the conclusion that little or no migration occurred among the extant populations separated by large geographic distances or river systems. However, the sharing of haplotypes between some such populations, for example between Batang Ai and Bario (HS6), and between Batang Ai and Ulu Limbang/Ba Kelalan (HS2) provided support that T. douronensis had a historically widespread natural distribution in the region probably during the Quaternary period. Overall, the present study was able to shed light on the taxonomy and population structure of T. douronensis in Malaysian Borneo

The Influence of Alien Fish Species on Native Fish Community Structure in Malaysian Waters

Introduction of alien fish species has resulted in major global change, harming native species and communities throughout the world. The main objectives of this review were to examine the species composition, ecology, and distribution of alien fish species in natural water bodies and evaluate the role and contribution of alien fish species through aquaculture to socio-economic development in Malaysia. The rate of introduction and the number of alien fish species introduced into local habitats have greatly increased since the early twentieth century. A statistical analysis of habitat differences among native fish species in Malaysia indicated that differences in fish assemblage structure in various sites was associated with differences in physical habitat. However, the occurrence of alien species has not only changed the structure of native ichthyo-fauna groups but has also caused ecological damage and economic harm to local fishermen. At present, alien fish species inhabit diverse environments including highland and isolated streams, rivers, rice fields, swamps, drainage areas, dams and reservoirs, lakes created from former mining areas, and estuaries in Malaysia. The examination of species composition, distribution and movement of alien fish in natural habitats revealed that these species have seriously spread and are now distributed in diverse aquatic habitats of Malaysia. This in turn provided evidence that there are no restrictions or limitations to the spreading of alien fish species in the natural habitats of Malaysia

Genetic characterization of the two colour-type of Kelah

Randomly Amplified Polymorphic DNA (RAPD) marker was used to examine the genetic relationships among three populations of two different colour-types (silver-bronze and reddish) of ikan kelah (Tor tambroides). Sixty three individuals of the kelah were sampled from Sia River of Pahang and Kampung Esok River of Negeri Sembilan (silverbronze)and Nenggiri River of Kelantan (reddish). Twelve RAPD primers generated a total of 226 scorable loci with 100% polymorphism across the sixty-three individuals. The RAPD banding patterns and sizes ranged from 4 to 17 and from 100bp to 1500bp, respectively. The intra-population UPGMA dendrogram produced two major clusters, with the Nenggiri River (Kelantan) samples formed a subcluster in both major clusters dominated by the Pahang samples (Cluster 1) and N. Sembilan (Cluster 2) samples, respectively. The inter-population UPGMA showed that the Kelantan samples were genetically closer to the N. Sembilan samples than to the Pahang samples. Thus, the results of this study did not support the hypothesis that the two colour-types of T. tambroides were genetically distinct from each other

A snapshot study on larval fish diversity in selected mangrove areas of Peninsular Malaysia, Malaysia / Izzati Adilah Azmir... [et al.]

The study on composition, abundance and diversity of larval fish was conducted with the aim to attain information on larval fish breeding ground and made easy for fishery management. Larval fish were collected during September 2015 from mangrove areas of Pekan Pahang, Pendas Johor, Matang Perak and Setiu Terengganu using a bongo net, towed at a depth of about 0.5 m from the surface for 5 min against the tidal flow. A total of 354 larval fish were collected, representing 21 families and 51 species. The top 3 families were Gobiidae (39.26%), Engraulidae (14.97%) and Clupeidae (14.40%), occurred in all sampling areas except in Setiu. The most abundant 11 species formed about 50% of all collected larval fish. Gobiidae spp. were the most abundant, making up 17.8% of the total catch, followed by Clupeidae spp. (12.7%), Engraulidae spp. (8.2%), Ambassis dusumieri (6.5%), Thryssa kammalensis (4.8%), Pseudogobius masago (both 4.8%), Sillaginidae spp. (4.2%), Ambassidae spp. (3.4%), Pseudogobius sp. (3.4%), Blenniidae spp. (2.8%), and Hemigobius hoevenii (2.5%). The highest diversity of larval fish was recorded for Pendas, Johor with Shannon Wiener index Hs = 2.699, and the lowest was Setiu, Terengganu (Hs = 0.832). The highest evenness index of larval fish species was recorded for Pekan, Pahang with Es = 0.815 and the lowest for Setiu Terengganu with Es = 0.465, indicating high single-species dominance. Species overlapping was the highest between Pendas and Setiu at 14.3%, and zero similarity of fish composition was recorded between Matang and Setiu according to Jaccard coefficient. Findings from surveillance of larval fish species provide valuable information for future biodiversity studies and allow better management of biodiversity resources in the mangrove ecosystem of Malaysia