Synbiotic Application to Enhance Growth, Immune System, and Disease Resistance Toward Bacterial Infection in Catfish (Clarias gariepinus)
Author: Esti Handayani Hardi, Rudy Agung Nugroho, Rita Rostika, Choirum M. Mardliyaha, Komsanah Sukarti, Widyaningsih Rahayu, Ali Supriansyah, Gina Saptiani
Photo by Supersmario from Getty Images/Canva
This research comprehensively evaluated the additional extract of Solanum ferox (SFE) and probiotic Lactobacillus casei (LC) on catfish (Clarias gariepinus var.) feed to enhance growth, feed efficiency, and resistance toward Aeromonas hydrophila and Pseudomonas fluorescens bacterial infection. Five different pellet types were made by adding various composition of SFE and LC as follows: pellet 1 (0 SFE + 0 LC), pellet 2 (0 SFE + 10 g kg 1 LC), pellet 3 (2 g kg 1 SFE + 10 g kg 1 LC), Pellet 4 (4 g kg 1 SFE +10 g kg 1 LC), Pellet 5 (6 g kg 1 SFE +10 g kg 1 LC). In total, 150 Catfish (initial weight ± 4 g) were randomly distributed into 15 plastic boxes and cultured for 12 weeks.
Catfish were fed with different composition pellets for two weeks, followed by a regular pellet. The observation of growth was examined in weeks four and eight after feeding time. In week 8, the bacterial challenge against A. hydrophila and P. fluorescens was performed, and the observation was continued until week 12.
The results showed that catfish grew to weigh an average of 45 g in week 8. Catfish fed higher concentrations of SFE and LC extractions showed a specific growth rate significantly higher (8–9%) than that of the control treatment catfish.
Additionally, SFE and LC extractions enhanced immune system function between weeks four and eight in comparison with other treatments. Resistance against bacterial infection increased with the SFE extraction to reach 99.65–100%. Fish feed containing only the LC extraction also showed higher resistance than control-treatment feed. In conclusion, higher concentrations of SFE and LC extractions in catfish feed has been shown to enhance growth, with no attendant risk.
Importantly, the use of the synbiotics enhanced both the immune system and resistance to A. hydrophila and P. fluorescens bacterial infections.
Keywords: Solanum ferox, Lactobacillus casei, Catfish, Aeromonas hydrophila, Pseudomonas fluorescens
Prebiotics (Hardi et al., 2018a, 2018b; Kurniasih et al., 2013; Nugroho and Fotedar, 2015; Ringø and Song, 2015; Zhang et al., 2013), probiotics (Akbari Nargesi et al., 2020; Kurniasih et al., 2013; Nayak, 2010; Verschuere et al., 2000; Widanarni et al., 2014), and synbiotics (Amenyogbe et al., 2020; Praseto, 2015; Yılmaz et al., 2020) have been previously used in aquaculture to enhance growth, immune systems, and disease resistance, reduce feeding costs, restore the cultivation environment, and help sustainable aquaculture evolve.
The product of mixing probiotics and prebiotics is commonly known as synbiotics, and was first introduced by Schrezenmeir and de Vrese (2001) to support the survival rate and growth of beneficial bacteria in the digestive system. Synbiotics are a balanced combination of probiotics and prebiotics which have the potential to rapidly enhance aquaculture production through increased fish growth and improved immune systems, digestion and absorption, disease management, and
water quality control (Okey et al., 2018; Torrecillas et al., 2018; Van Nguyen et al., 2019; Waagbø and Remø, 2020).
The extraction of S. ferox (SFE; more commonly known as “hairy eggplant”) as an immunostimulant raw material for fish has been widely investigated (Hardi et al., 2016a, 2016b, 2017, 2018a, 2018b, 2018c, 2019) for its potential to supply nutritious quantities of carbohydrates, flavonoids, and alkaloids. For example, SFE has produced satisfying results through constitution as fish feed for tilapia and goldfish, significantly elevating digestibility in comparison to non- extraction fish feed. Prebiotics can take the form of mannan oligosaccharides, fructose oligosaccharides, galactooligosaccharides, and isomaltooligosaccharides, and improve fish health by boosting the work of the intestinal microbiota, intestinal histology, and hematological parameters, and increasing disease resistance (Ringø and Song, 2015).
Lactobacillus bacteria is a probiotic which undoubtedly enhances the digestive fish feed mechanism (Okey et al., 2018). Additionally, synbiotics in aquaculture have been broadly reported to improve production, as measured by growth rates, enhanced immune systems, improved digestion and absorption, increased disease resistance, and greater water quality control (Carnevali et al., 2006; Hussein et al., 2020; Okey et al., 2018; Thompson et al., 1999; Verschuere et al., 2000).
However, little research has yet been conducted on the application of prebiotics and probiotics specifically on catfish growth, immune function, and disease resistance. Thus, the present research evaluated the effects of prebiotic and probiotics application in catfish feed. For this study, a single S. ferox extract combined with the L. casei (LC) probiotic was administered to catfish and evaluated for its effects on growth, immune system function, and resistance to bacterial A. hydrophila and P. fluorescens infection.
This article has been published in Aquaculture
Esti Handayani Hardi a,b,*, Rudy Agung Nugroho b,c, Rita Rostika d, Choirum M. Mardliyaha a, Komsanah Sukarti a, Widyaningsih Rahayu a, Ali Supriansyah a, Gina Saptiani a,b
a Microbiology Laboratory of Fisheries and Marine Sciences, Department of Aquaculture, Fisheries and Marine Science, Mulawarman University, Indonesia
b Research Center of Medicine and Cosmetics from Tropical Rainforest Resources PUI-PT OKTAL, Mulawarman University, Samarinda, Indonesia
c Department of Biology, Faculty of Mathematics and Natural Sciences, Mulawarman University, Samarinda, East Kalimantan, Indonesia
d Fisheries Study Program, Fisheries, and Marine Sciences Faculty, Padjadjaran University, Indonesia
To appear in: Elsevier Aquaculture
Volume 549, 25 February 2022, 737794
Received 20 January 2021, Revised 25 May 2021, Accepted 29 November 2021, Available online 3 December 2021, Version of Record 7 December 2021.