Top-spraying xylanase and β-glucanase improves digestible energy content and optimizes protein and amino acids digestibility in high-fiber diet fed to growing Nile tilapia

Top‐sprayed mixture of phytase, xylanase and β‐glucanase enhances energy and nutrient matrix in all‐vegetable diets for Nile tilapia

“…To the author's knowledge, no previous studies have reported the effects of phytase, in combination with the XB, on the ADC of amino acids in Nile tilapia. These findings align with the previous studies involving individual supplementation of phytase in Nile tilapia (Riche et al, 2002) and grass carp ( Ctenopharyngodon idella ) (Liu et al, 2013), xylanase and β‐glucanase in Nile tilapia (Brito et al, 2021), and phytase and xylanase in Atlantic salmon ( Salmo salar ) (Jacobsen et al, 2018). Previous studies have demonstrated that the phytic acid's detrimental effect on the ADC of amino acids is associated with an increase in the endogenous amino acid loss in the intestine rather than directly affecting protein digestibility (Cowieson et al, 2004).…”

“…A similar phenomenon was observed in the ADC of P in the European seabass fish offered the same commercial mixture (0.4 g/kg diet) of XB used in the current study (Magalhães et al, 2018). This phenomenon was further reinforced in rainbow trout (Dalsgaard et al, 2012) and Nile tilapia (Brito et al, 2021; Maas et al, 2019). The most reasonable explanation is that xylanase releases the bound minerals during the NSP cleavage processes (Frølich & Asp, 1985; Persson et al, 1991).…”

“…The control diet contained 5 g kg −1 of Cr 2 O 3 as an indigestible marker (Table 1). We assumed that all‐vegetable containing blend of XB (1120 TXU kg −1 diet of 1,4‐β‐xylanase and 500 TGU kg −1 diet of 1,4‐β‐glucanase) enhances the digestible energy content by 0.41 MJ kg −1 diet (Brito et al, 2021), and phytase at 1000 FTU kg −1 diet increases the available P content by 4.5 g kg −1 (Pontes et al, 2021). These assumptions were based on those mentioned above‐published research conducted in our laboratory to determine the optimum levels of these exogenous enzymes supplemented in all‐vegetable diet fed to Nile tilapia.…”

“…Additionally, β‐glucanase hydrolyzes β‐glucan units present in the endosperm cell walls of cereals (Bach Knudsen, 2014). For instance, evidence from previous research studies revealed that xylanase and β‐glucanase supplementation decreased intestinal viscosity and increased the ADC of gross energy and nutrients in Nile tilapia, Oreochromis niloticus (Brito et al, 2021; Sinha et al, 2011).…”

“…Therefore, vegetable ingredients, such as wheat bran, could be applicable in large‐scale aquafeed production (Ghosh et al, 2019). Recent research studies conducted in our laboratory have proved that individual phytase and a mixture of xylanase and β‐glucanase can improve the nutritive value of the all‐vegetable diet fed to Nile tilapia (Brito et al, 2021; Pontes et al, 2021). Nevertheless, based on the author's knowledge, the effects of the exogenous phytase and xylanase and β‐glucanase preparation enzymes individually or in combination with increasing digestible energy, digestible protein and available P contents in all‐vegetable diets fed to Nile tilapia are yet to be investigated.…”