Recently, global demand for seafood such oysters is increasing as consumers seek healthy and nutritive alternatives to a diet dominated by animal protein. This trend is attributed to the growing interest in sustainable seafood strategies and a surge in customer demand. Despite oysters being one of the most promising seafoods, the oyster industry faces various challenges, such as increased infectious diseases promoted by climate change, pollution, and environmental burdens. Hence, the industry’s current challenges must be addressed to ensure long-term viability. One of the current challenges in the production industry (in response to climate change) is mortality or poor product quality from microbial infection. This review reveals that climate change fosters pathogen development, significantly impacting disease spread, host susceptibility, and the survival rates of oysters. Rising temperatures, driven by climate, create favourable conditions for bacteria and viruses to multiply and spread quickly, making oysters more susceptible to diseases and ultimately adversely affecting the oyster industry. Climate-induced changes in oyster-associated microbes and pathogens, coupled with disruptions in biochemical pathways and physiological functions, can lead to increased disease outbreaks and reduced survival in the industry, impacting production and profitability. These adverse effects could result in decreased oyster supply, potentially affecting seafood markets and prices, and necessitate additional investments in disease management strategies. This review identifies and highlights how aquatic pathogens promoted by climate change will affect the oyster industry on a global scale. This review also presents an in-depth global assessment of climate change’s impacts on oysters relative to their disease exposure and pathogen spread and identifies possible future directions.
This research examined the role of nano curcumin (NC) on growth performances, body composition, and blood parameters of red tilapia (Oreochromis sp.) challenged with Aspergillus flavus. Fish (5.0 g ± 0.30) were randomly distributed in four equal groups (20 fish per pond in triplicates) and fed various concentrations of NC fortified with 0 (Control), 40 mg/kg (NC1), 50 mg/kg (NC2), and 60 mg/kg diet (NC3) of nano curcumin. After eight weeks of the feeding trial, the fish were challenged with A. flavus for 15 days, and the cumulative mortality was recorded. Fish fed with different concentrations of NC improved significantly (p < 0.05) the growth performances, feed utilization, and survival rate. There was no significant (p > 0.05) difference between NC2 and NC3 treatments. However, NC3 exhibited higher performances. Fish feed supplemented with NC decreased the mortality rate when challenged with A. flavus. Hence, dietary supplementation of NC enhanced the growth and health status of Oreochromis sp. and protected it from A. flavus infection. This study suggests the optimum inclusion level of NC is a 50–60 mg/kg diet.
U(Universiti Sains Malaysia Centre For Marine And Coastal Studies (Cemacs)
Universiti Sains Malaysia Centre For Marine And Coastal Studies (Cemacs)
This study used a two-phase feeding trial to determine the influence of selected dietary prebiotics and probiotics on growth performance, feed utilisation, and morphological changes in snakehead (Channa striata) fingerlings as well as the duration of these effects over a post-experimental period without supplementation. Triplicate groups of fish (22.46 ±0.17 g) were raised on six different treatment diets: three prebiotics (0.2% β-glucan, 1% galacto-oligosaccharides [GOS], 0.5% mannan-oligosaccharides [MOS]), two probiotics (1% live yeast [Saccharomyces cerevisiae] and 0.01% Lactobacillus acidophilus [LBA] powder) and a control (unsupplemented) diet; there were three replicates for each treatment. All diets contained 40% crude protein and 12% crude lipid. Fish were fed to satiation three times daily. No mortalities were recorded during Phase 1; however, 14% mortality was documented in the control and prebiotic-amended fish during Phase 2. At the end of Phase 1, growth performance and feed utilisation were significantly higher (p<0.05) in the LBA-treated fish, followed by live yeast treatment, compared with all other diets tested. The performance of fish on the three prebiotic diets were not significantly different from one another but was significantly higher than the control diet. During Phase 2 (the post-feeding phase), fish growth continued until the 6th week for the probiotic-based diets but levelled off after four weeks for the fish fed the prebiotic diets. The feed conversion ratio (FCR) was higher in all treatments during the post-feeding period. The hepatosomatic index (HSI) did not differ significantly among the tested diets. The visceral somatic index (VSI) and intraperitoneal fat (IPF) were highest in the LBA-based diet and the control diet, respectively. The body indices were significantly different (p<0.05) between Phases 1 and 2. This study demonstrates that probiotic-based diets have a more positive influence on the growth, feed utilisation, and survival of C. striata fingerlings compared with supplementation with prebiotics.
The present study investigated the effect of Chlorella vulgaris on growth performance, feed consumption, body composition, and immune response of white shrimp (Litopenaeus vannamei) against Vibrio parahaemolyticus infection. Shrimps (4.00 ± 0.04 g) were divided into five groups (3 replicates/20 each) in 15 hapa (1 m3) and cultured for 56 days with five C. vulgaris experimented diets at five different concentrations (0, 15, 20, 25, and 30 g/kg feed). Growth performance, feed utilization, biomass, and body composition (protein, lipid, and ash) were analyzed and revealed significant increase (P < 0.05) in shrimp fed the high C. vulgaris diet. Additionally, the survival rate of shrimp in all experimental feeds was improved, but was not significant. Shrimp fed with C. vulgaris at different concentrations showed significantly (P < 0.05) higher antioxidant activity. The study showed that shrimp fed with a concentration of 30 g/kg C. vulgaris in the diet showed significantly (P < 0.05) highest disease resistance against the pathogen tested. Hence, dietary C. vulgaris might be used to improve growth performance, feed utilization, body composition, and immune biomarker responses, leading to disease resistance in cultured shrimp.