Use of former food products in dairy buffalo nutrition: In vitro and in vivo evaluation

Abstract

A feeding strategy that maintains high content of functional molecules in buffalo milk has been verified by giving Sorghum vulgare as green fodder, but it is not available all year round. The aim of this study was to evaluate the inclusion of former food products (FFPs) containing 87% biscuit meal (nonstructural carbohydrate: 60.1%; starch 14.7; crude protein 10.6), in the diet of buffaloes in terms of: (a) fermentation characteristics through gas production technique; (b) milk yield (MY) and quality; (c) content of some biomolecules and total antioxidant activity. The experiment was performed involving 50 buffaloes divided into two groups: Green group and FFPs group (animals fed Total Mixed Ration with either green forage or FFPs respectively). Daily MY was recorded and milk qualitative analyses were determined monthly for 90 days. Furthermore, fermentation characteristics of the diets were studied in vitro. No significant differences were recorded in feed intake, BCS and MY and quality. Similar in vitro fermentation data of two diets were found, with slight differences in terms of gas production and degradability. During the incubation, kinetic parameters showed a faster fermentation process with the diet of the FFPs group in relation to Green group (p < 0.05). Green group had higher levels (p < 0.01) of γ-butyrobetaine, glycine betaine, l-carnitine and propionyl l-carnitine in milk, whereas no differences were observed for δ-valerobetaine and acetyl l-carnitine. Total antioxidant capacity and iron reduction antioxidant assay were higher (p < 0.05) in the plasma and milk of the Green group. The administration of a diet high in simple sugars, obtained with FFPs, seems to favour the ruminal biosynthesis of some metabolites in milk, such as δ-valerobetaine and acetyl- l-carnitine, similar to green forage administration. Overall, the use of biscuit meal can be an alternative to green fodder when it is not available to ensure environmental sustainability and optimize costs without compromising milk quality.

Keywords: fermentation kinetics; green feed; health-promoting biomolecules; in vitro degradability; milk quality.