Inulin Supplementation in Diets for Tropical Gar (Atractosteus tropicus) Larvae: Effects on Growth, Survival, and Digestive and Antioxidant Enzyme Activities

Abstract

The effect of adding inulin to balanced diets for tropical gar (Atractosteus tropicus) larvae on growth, survival, digestive enzyme activity, and antioxidant activity was evaluated. The diets were supplemented with 0.5, 1.0, 1.5, 2.0, and 2.5% inulin in addition to a control diet (0% inulin). A total of 1800 larvae of A. tropicus distributed in 18 tanks were used; the larvae were fed five times a day (8:00, 11:00, 13:00, 15:00, and 18:00) with Artemia nauplii from the absorption of the yolk (from 3–7 days after hatching, DAH) up to 10 DAH, which was mixed with the experimental feeds from 8–11 DAH (co-feeding) and exclusively with the balanced diets from 12 DAH to 21 DAH. Larvae fed the control diet (0% inulin) had the highest growth in weight and length, followed by fish fed the 2.5 and 2.0% inulin inclusions. However, survival showed that the fish fed with the inclusion of 2.5% inulin had the highest percentage (34.7%) compared to the rest of the treatments. On the other hand, the highest digestive enzymatic activities (acid and alkaline proteases, amylase, and lipase) were recorded in the larvae fed with 2 and 2.5% inulin. Likewise, catalase (CAT) and superoxide dismutase (SOD) activities were higher in larvae fed the control diet with 0% inulin. Supplementation of 2.0% to 2.5% inulin in the diet is recommended for A. tropicus larvae as it improves survival and digestive enzyme activity during this early stage of life.

Inulin Inulin supplementation in feed as a prebiotic for red tilapia Oreochromis sp.

“…Prebiotics can improve substrate hydrolysis and increase the number of metabolites produced by the intestinal flora (Ziółkowska et al, 2021), improving fish absorption and digestion (Kumar et al, 2018). The study results are supported by De La Cruz-Marín et al (2023), who found that the activity of protease and amylase in tropical gar (Atractosteus tropicus) larvae increased with inulin supplements in feed. Enzyme activity is stimulated by adding inulin in the right ratio so that the nutrients from the feed can be easily digested and the molecules can be absorbed, thereby achieving better digestion (Hunt et al, 2019).…”

“…Dobrianska et al (2021) noted that when the intestine is welldeveloped, nutrient absorption is improved, which has an impact on growth and decreases FCR. There is variation in growth, feed utilization, and health benefits when the use of prebiotics depends primarily on the species, time of application, and dosage of the supplement, as well as the type of prebiotic (De La Cruz-Marín et al, 2023). Red tilapia reared for 30 days did not experience death or the survival rate reached 100% in all treatments.…”

Effect of the combination of fluoxymesterone and a commercial blend of additives on the sex proportion, growth, and survival of Nile tilapia (Oreochromis niloticus) fry

“…Commercial additives containing one or several of the ingredients included in the blend used in this work (cinnamon, garlic, vitamin C, inulin) have been shown to improve growth performance (Toyama et al 2000, Naftal-Gabriel et al 2019, Rahman et al 2019, Fattahi et al 2021, Habiba et al 2021, Pérez-Jiménez et al 2022, Faust et al 2023). However, in other studies, although evidence of improved health, chemical, digestive, or hematological parameters has been observed, no positive effect on growth was recorded (Kalko-Schwarz et al 2011, Abdelhamid et al 2012, Mörschbächer et al 2014, Sakaguti-Graciano et al 2014, de Araújo et al 2018, de la Cruz-Marín et al 2023. These variations in growth performance could result from several aspects, including species, age, duration of additive supplementation, and, more importantly, concentration and type of additive (Dawood et al 2018).…”

Fish Responses to Alternative Feeding Ingredients under Abiotic Chronic Stress

“…Fish fed with 2.5% inulin showed diminished intestinal activities of GPx, SOD, and CAT, which resulted in improved antioxidant status. Additionally, the larvae survival increased as the concentration of inulin increased [ 55 ]. In Nile Tilapia ( Oreochromis niloticus ), similar effects of dietary inulin were observed under 16 hypersaline-stressed conditions for eight weeks, similar to a chronic state as CAT and GAST diminished in the gut [ 56 ].…”