Development of sperm cryopreservation protocol for patin buah, Pangasius nasutus.

The development of sperm cryopreservation for Pangasius nasutus is necessary in order to serve the growing demand of this species through artificial fertilization and the preservation of valuable strains of male broodstocks. In the present study, the basic protocol of sperm cryopreservation for P. nasutus was established by identifying the optimal conditions for optimum cryoprotectant, toxicity of cryoprotectants, extenders, freezing condition and dilution ratio. Methanol (MeOH) at 10% concentration had the best post-thaw motility (26.3 ± 0.9%) and curvilinear velocity (VCL) compared to dimethyl acetamide and dimethyl sulfoxide. MeOH was the least toxic cryoprotectant; sperm suspended in 5 and 10% MeOH maintained motility up to 50 min. No significant differences were detected between the three types of extenders tested (0.9% sodium chloride, Calcium-free Hanks' Balance salt solution and ringer solution). P. nasutus sperm had a narrow range of optimal cooling rate. Significantly higher post-thaw motility was identified when cooling at 9.23 °C min-1, obtained by freezing at height of 14 cm above liquid nitrogen vapor for 7 min, showing lower cooling rate is suitable for this species. However, when cooling below and above the optimal cooling rate, post-thaw motility dropped drastically. There were no significant differences among the dilution ratios investigated, indicating the volume of cryodiluent at all tested ratios (1:9, 1:19 and 1:49) was sufficient for the protection of cells during the cryopreservation process. The development of the protocol for cryopreserved P. nasutus sperm will assist artificial seed production and provide an important tool for genetic and breeding research.

Effects of pH and temperature on striped catfish Pangasianodon hypophthalmus juvenile: Data on growth performance and survival rate.

The growth performance and survival rates of juvenile striped catfish, Pangasianodon hypophthalmus, reared at various levels of pH and temperature were described in this article. Two rearing trials were conducted separately for pH and temperature where both trials lasted for 35 days. One hundred and twenty juveniles (1.5 ± 0.23 g) were randomly stocked into 12 rectangle glass aquariums (n = 10 fish/tank; three replicates per treatment) with 100 L of water for each trial. The treatment consisted of four different pH level (7.5, 8.0, 8.5 and 9.0) and four different temperature level (26 °C, 28 °C, 30 °C and 32 °C). The survival of fish was counted at the end of experiments, and the weight of the juvenile was measured once a week. The quantification of feed intake was determined through the measurement of the residual weight of the feeds after the feeding process. Upon the conclusion of the experiment, the data pertaining to weight and feed intake were utilized to calculate the specific growth rate (SGR) and food conversion ratio (FCR) as indicators of growth performance. Additionally, the number of live fish was employed to ascertain the survival rate. The data obtained from the calculation of SGR, FCR and survival rate were next subjected to a normality test, one-way analysis of variance (ANOVA), and a Tukey post-hoc test. The information in this article will help in the business, experimental, and personal usage for P. hypophthalmus juveniles rearing process.

Enhancing Reproductive Performance of Freshwater Finfish Species through Dietary Lipids.

Dietary lipid manipulation in the feed of commercially cultured finfish is used not only to improve production and culture but also to enhance their reproductive performances. The inclusion of lipid in broodstock diet positively affects growth, immunological responses, gonadogenesis, and larval survival. In this review, existing literature on the importance of freshwater finfish species to aquaculture and the inclusion of dietary lipid compounds in freshwater fish feed to accelerate the reproduction rate is being summarized and discussed. Although lipid compounds have been confirmed to improve reproductive performance, only a few members of the most economically important species have reaped benefits from quantitative and qualitative lipid studies. There is a knowledge gap on the effective inclusion and utilization of dietary lipids on gonad maturation, fecundity, fertilization, egg morphology, hatching rate, and consequently, larval quality contributing to the survival and good performance of freshwater fish culture. This review provides a baseline for potential future research for optimizing dietary lipid inclusion in freshwater broodstock diets.

Sexual dimorphism of Malaysian Mahseer, Tor tambroides broodstock reared in captivity: Morphometric measurements dataset.

Despite having high economical value and declining wild population, the aquaculture of the Malaysian mahseer (Tor tambroides) is still way behind. Crucial information such as on its sexual dimorphism is scarce thus making its broodstock management in captivity challenging. The first step in studying fish sexual dimorphism is by observing and identifying the morphological differences between each sex. Thus, this article collected and described morphometric measurements data of broodstock reared in captive conditions. The broodstock were reared and raised in captivity for five years since they were bought from a local commercial supplier while they were five-inch fingerlings. Seven conventional and 21 Truss network morphometric measurements were taken from 27 male (TL: 53.88 ± 2.86 cm; W: 1.82 ± 0.23 kg) and 27 female (TL: 53.97 ± 3.62 cm; W: 1.86 ± 0.35 kg) T. tambroides broodstocks using digital image analysis. Photograph of the fish broodstocks were captured and the morphometric measurements were conducted using imageJ freeware. Statistical analysis was later conducted on the morphometric data to identify the morphological differences between the broodstocks. This dataset will not only aid the sex identification of this species but also in stock population studies thus accelerating the development of T. tambroides aquaculture while improving its conservation efforts.