Phytogenic Feed Additives as a Sustainable Alternative to Antibiotics: Enhancing Growth and Disease Resistance in Nile Tilapia (Oreochromis niloticus)

• Published in: Animals (Basel) Vol. 15; no. 3; p. 380
• Main Authors: Gruber, Christina, Ocelova, Vladimira, Kesselring, Jutta C., Wein, Silvia
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.02.2025; MDPI
• Subjects: Additives; Animal feeding and feeds; Animals; Antibiotics; Antioxidants; Aquaculture; Bacterial infections; Costs (Law); Diet; Disease; Drug resistance in microorganisms; Efficiency; Enzymes; Ethylenediaminetetraacetic acid; Experiments; Feeds; Fish hatcheries; Fishes; Growth; growth performance; Health aspects; immunity; Mortality; Nile Tilapia; Oils & fats; phytogenic feed additive; Proteins; resistance; Statistics; Streptococcus agalactiae; Tilapia; Water levels; Vietnam; Austria; phytogenic feed additive; growth performance; immunity; Nile Tilapia; Streptococcus agalactiae; resistance
• ISSN: 2076-2615; 2076-2615
• DOI: 10.3390/ani15030380

Pathogens and challenging conditions in fish farming are common problems that cause mortality and reduce growth performance. Phytogenic feed additives can support the immunity of fish and thereby improve performance, production, and disease resistance. Two experiments with Nile Tilapia aimed to evaluate the effects of a matrix-encapsulated phytogenic additive (Digestarom® P.E.P. MGE) in different feed formulations, which vary in the marine meal inclusion level (5% and 12.8%), on growth performance and resistance against Streptococcus agalactiae. Fish were stocked in a recirculating aquaculture tank system per experiment and were fed with diets with or without the phytogenic supplementation for 8 weeks (six replicates per group). After an intraperitoneal injection with a sterilized saline solution and bath immersion with S. agalactiae (5 × 106 CFU/mL), mortality of the fish was recorded for 20 days. Independent of the diet formulation, the supplementation with the phytogenic feed additive significantly improved the fish production; feed conversion ratio; immune response (mainly lactic acid dehydrogenase, differential blood cell counts, and the lysozyme activity in blood); and fish survival after the S. agalactiae challenge. Thus, phytogenic feed additives are promising strategies to improve Nile tilapia production by enhancing fish growth performance, health, and protection against S. agalactiae infections.