Effects of GroBiotic®-A supplementation on growth performance, body composition and liver and intestine histological changes in European Seabass (Dicentrarchus Labrax) juveniles

Abstract

The effects of GroBiotic®-A supplementation on growth performance, body composition, liver and intestine histology in European seabass (Dicentrarchus labrax) juveniles were evaluated. The commercial GroBiotic®-A was added to diets at four different levels (0, 1, 2 and 3%), three replicates and fed 4 times a day (9:00, 11:30, 14:00, 16: 30 hours) for 60 days as ad libitum. Total 480 European seabass juveniles with a starting weight of 1.40±0.08 g were randomly stocked into 12 tanks with a volume of 1 m3. At the end of the study, the changes observed in weight, feed conversion ratios (FCR) and survival rates were calculated as 6.69 ± 5.35-7.40 ± 5.47, 0.80 ± 0.18-0.88 ± 0.20 and 96.6 ± 1.51-100 ± 0.0, respectively. When the body composition of the control and treatment groups were compared, no statistically significant differences were observed between the protein and lipid values (p>0.05), except ash (p <0.05). Histological sections of intestinal tissue; the number of goblet cells was higher than that of the control group. The highest values were determined in the group supplemented 2% GroBiotic®-A. The highest microvillus length was found in the group added 1% GroBiotic®-A. It was detected an inverse relationship between microvillus length and contribution rates as the the GroBiotic®-A additive levels increased. Also, degeneration and necrosis was detected in hepatocyte cells of seabass juvenile fed with diets supplemented 2% and 3% GroBiotic®-A as well as increase of the number of fatty vacuoles in liver tissue due to the increase in the amount of GroBiotic®-A. In conclusion, when the growth parameters, body composition and histological data were evaluated together, the feeding group supplemented 1% GroBiotic®-A performed the best.

The effects of Dietary GroBiotic®-A on growth performance and survival rate of Penaeus semisulcatus (de Haan, 1844) juveniles

“…Similar to the results obtained in our study, the addition of GBA did not affect the survival rate of fish in rainbow trout Betiku et al, 2018;Bockus et al, 2021), red drum (Buentello et al, 2010;Rossi et al, 2017), tilapia (Vechklang et al, 2012), starry flounder (Wang et al, 2016), goldfish (Raggi et al, 2012), Totoaba macdonaldi (González-Félix et al, 2018), Largemouth bass (Yu et al, 2019) and European sea bass (Yazıcı et al, 2020).…”

“…On the other hand, the results of studies on the growth performance of Grobiotic-A in fish are conflicting. Previous studies indicated that GroBiotic®-A has no effect on growth performance in rainbow trout (Betiku et al, 2018;Bockus et al, 2021;Sealey et al, 2007), brown trout Salmo trutta macrostigma, (Sönmez et al, 2020), European sea bass Dicentrarchus labrax, (Yazıcı et al, 2020), red drum (Buentello et al, 2010;Rossi et al, 2017) and tilapia (Peredo et al, 2015;Vechklang et al, 2012). However, some researchers reported that Grobiotics showed an increase in growth performance in their studies with rainbow trout Oncorhynchus mykiss , red drum Sciaenops ocellatus , tilapia Oreochromis niloticus, (Zheng et al, 2011) fathead minnow Pimephales promelas, (Lochmann et al, 2011), great sturgeon Huso huso , starry flounder Platichthys stellatus (Wang et al, 2016), largemouth bass Micropterus salmoides (Yu et al, 2019).…”