VALUTAZIONE NUTRIZIONALE DI DIETE E ADDITIVI NELL'ALIMENTAZIONE DEL CANE

In the last few years, there has been an increased interest in pets’ nutrition and feeding. In term of research both basic and applied nutrition has expanded the knowledge of canine nutrition, it is now known that a well-balanced diet must include not only macronutrients but also an appropriate amount of minerals, vitamins, certain essential amino acids (from proteins), and specific essential fatty acids (from fats). These components are needed to build and maintain tissue and carry out biological reactions, and the necessary amounts vary somewhat with the dog's stage of life (puppy, adult, pregnancy, senior), activities (sport, game, ect.), and physiological state (pregnancy and lactation). Above this in the recent past, there have been an increase in different types of diets present in the market that are characterized by different composition and target market segments (premium, dietetic, ect.). In light of this, in the present thesis three main topics have been addressed: i) the nutritional characteristics and in vitro digestibility of different dogs’ diets available on the market (premium, super premium, with particular nutritional purposes, wet food and BARF); ii) the effects of yeast supplementation in pregnant and lactating bitches and their effects in their respective puppies; iii) the effects of yeast supplementation in adult dogs. In particular, the thesis investigated the composition the in vitro digestibility of different dogs’ diets, and the effects of two yeasts, Saccharomices cerevisiae and S.cerevisiae var boulardii. In this latter case the studies investigated the effects of yeast on: growth performance (weight, body condition score and feed intake), fecal characteristics (fecal score, dry matter, total apparent digestibility and presence of pathogens), local immune response (IgA), e intestinal microbiota and fecal odor profile (by electronic nose). Thus, it can be suggested that different market names/classifications like premium, super premium, and BARF diets, do not always support big nutritional differences. All diets are in line with dogs ‘main recommendation. When yeast supplementation is consider the effects observed in the present studies seem to be related to an optimization of feed preparation/diet according to the ideal national profile, and for this reason not always so visible in term of recorded figures. A key aspect in defying the response however is also the exposure time that at least in one of the studies, was probably limited. For this reasons large-scale and long-term studies that can generate high-quality nutritional evidence on the relationships between diets and supplements are required.