Evaluation of the Combined Administration of Chlorella fusca and Vibrio proteolyticus in Diets for Chelon labrosus: Effects on Growth, Metabolism, and Digestive Functionality

Abstract

This study aimed to evaluate the combined effect of dietary Chlorella fusca and ethanol-inactivated Vibrio proteolyticus DCF12.2 (C + V diet) in Chelon labrosus juveniles, highlighting their nutritional, physiological, and morphological effects. The results showed that the combined dietary inclusion of C. fusca and V. proteolyticus significantly enhanced growth performance and feed utilization compared to the control group. The C + V diet increased the fish lipid quality index (FLQ), n-3 polyunsaturated fatty acids, and n-3/n-6 ratio, which might be beneficial in terms of human nutrition. The C + V diet considerably increased carbohydrate metabolic activity by statistically boosting plasma glucose. The dietary inclusion of C. fusca in conjunction with V. proteolyticus increased metabolic enzyme activity as well as intestinal absorption capacity compared to that found in the control group. In conclusion, the experimental diet was suitable for feeding C. labrosus, increasing their growth and the nutritional characteristics of the muscle and intestine, without causing tissue damage.

Effects of Phytase and Microalgae Supplementation on the Utilization of Aquafeeds for European Seabass (Dicentrarchus labrax) Formulated with a High Inclusion Level of Plant Protein

“…All the samples were screened via high-resolution field emission scanning electron microscopy (FESEM) (Carl Zeiss, Sigma 300 VP, Jena, Germany). All the digital images were analyzed with Image J (National Institutes of Health, USA) software and a morphometric analysis was performed to determine the enterocyte apical area (EA) [37].…”

Combined Dietary Administration of Chlorella fusca and Ethanol-Inactivated Vibrio proteolyticus Modulates Intestinal Microbiota and Gene Expression in Chelon labrosus

“…The microalga, Chlorella fusca (Chlorophyta), strain BEA1005B, from the Spanish Collection of Algae (BEA), was produced in pilot-scale photobioreactors (PBRs) at the SABANA Project facilities, located at the University of Almeria, Spain. Detailed methodologies for microalga cultivation are provided in García-Márquez et al [15], including specifics on culture conditions and processing steps such as harvesting, cell disruption, and spray-drying. Similarly, information on the culture and ethanol-inactivation process of the bacterium Vibrio proteolyticus DCF12.2, isolated from healthy wedge sole (Dicologlossa cuneata), is comprehensively documented in García-Márquez et al [15].…”

“…Detailed methodologies for microalga cultivation are provided in García-Márquez et al [15], including specifics on culture conditions and processing steps such as harvesting, cell disruption, and spray-drying. Similarly, information on the culture and ethanol-inactivation process of the bacterium Vibrio proteolyticus DCF12.2, isolated from healthy wedge sole (Dicologlossa cuneata), is comprehensively documented in García-Márquez et al [15].…”

“…The enhanced carbohydrate metabolic activity and increased enzymatic activity observed in the plasma further suggested metabolic improvements associated with the combined diet. Moreover, the diet contributed to heightened metabolic enzyme activity and augmented intestinal absorption capacity [15]. However, while the previous study offered valuable insights into the physiological benefits of the combined administration of C. fusca and V. proteolyticus, the influence of this diet on the intestinal microbiota and the immune response in C. labrosus was not assessed.…”

“…Given the potential significance of C. labrosus in aquaculture, research efforts have been directed towards optimizing its growth and nutritional qualities [12][13][14]. In this sense, in a previous study, García-Márquez et al [15] highlighted the significant growth-enhancing effects of the combined dietary inclusion of Chlorella fusca and ethanol-inactivated Vibrio proteolyticus in Chelon labrosus juveniles. As reported by the authors, the diet not only improved growth performance and feed utilization but also positively influenced lipid quality indices and n-3 polyunsaturated fatty acid composition, potentially increasing the nutritional value of this fish species for human consumption.…”