FIELD: food industry.SUBSTANCE: this invention relates to agriculture and fodder production, in particular, to a fodder additive and fodder containing the homotrimer, the heterotrimer, the homotetramer and/or the heterotetramer of a carbohydrate component, its derivative or extract or their mixtures； the said carbohydrate component is selected from the group consisting of a pentose saccharide and a hexose saccharide, glucuronic and galacturonic acid, the carbohydrate components linked with ?- or ?-links, as well as a medium chain fatty acid (MCFA) or its salt or derivative and/or their mixture, the said MCFA selected from the group consisting of capronic acid (C6), caprylic acid (C8), capric acid (C10) and lauric acid (C12). This invention also relates to application of the fodder additive or fodder for production of a composition for: improvement of microbial ecosystem in the animal gastrointestinal tract, selective control and regulation of enteropathogens in the animal gastrointestinal tract, optimisation of microbial colonisation of gastrointestinal tract by way of specific suppression and agglutination of enteropathogens, increase of body weight gain, reduction of fodder conversion and/or stimulation of farm animals specific growth.EFFECT: implementation of the group of inventions ensures increase of animal breeding production efficiency due to improvement of microbial ecosystem in the animal's gastrointestinal tract thanks to specific elimination of pathogens from the gastrointestinal tract.15 cl, 2 tbl, 1 dwg, 3 exНастоящее изобретение относится к сельскому хозяйству и кормопроизводству, а именно к кормовой добавке и корму, содержащему гомотример, гетеротример, гомотетрамер и/или гетеротетрамер углеводного компонента, его производную или экстракт, или их смеси, при этом указанный углеводный компонент выбран из группы, состоящей из пентозного сахарида и гексозного сахарида, глюкуроновой и галактуроновой кислот, и где углеводные компоненты связаны α- или β-связ
