Performance of crossbred dairy Friesian calves fed two levels of Saccharomyces cerevisiae: intake, digestion, ruminal fermentation, blood parameters and faecal pathogenic bacteria

Abstract

One of the major challenges facing the animal production industry in developing countries is to improve efficiency of production and to maintain feed utilization. Many attempts have been made by researchers to overcome these challenges, such as including the incorporation of antimicrobials and other natural products into animal feeds (Ahmed et al. 2015; Rojo et al. 2015; Morsy et al. 2016). Feed additives of microbial origin, ionophores and antibiotics have become a common practice in ruminant nutrition; however, most studies have been conducted with lactating cows or in vitro, with few studies on pre-weaned calves.