Testing the effect of including exogenous carbohydrases in plantbased feeds for gilthead seabream

Abstract

Non-starch polysaccharides (NSPs), carbohydrates present in plant ingredients, are formed by cellulose and other heteropolymers of more complex sugars such as mannose, xylose, and arabinose, among others. They give important differences in solubility, water retention capacity, interaction with other food ingredients, and in the intestinal microbiota. In many cases, NSPs form a matrix that hinders the access of digestive enzymes to the protein and starch present in seeds of cereals and legumes. Therefore, the use of enzymatic complexes capable of partially degrading NSPs, has shown positive effects in the nutritive use of feeds with high amounts of plant ingredients. Additionally, exogenous carbohydrases can promote the development of a beneficial microbiota and consequently results in a better health status. The inclusion of these enzymes has been evaluated in feed for freshwater species such as tilapia, catfish, rainbow trout and carp, but not in marine fish. Consequently, the present study aimed to assess the effect of including a commercial mixture of carbohydrases in a feed containing high amounts of plant ingredients on growth, digestion, metabolism, and gut microbiota in the gilthead seabream (Sparus aurata).