Ionophoric Additives to Augment Performance Outcomes and Economics in Ruminants

Abstract

Ionophores are a group of carboxylic polyether antibiotics used as ‘medicated feed additives’ for ruminants. These include monensin, salinomycin, lasalocid, narasin, maduramicin, semduramicin and laidlomycin propionate. Monensin acts by inhibiting gram-positive bacteria—including protozoa and fungi—result-ing in increased propionate production, decreased acetate and reduced methano­genesis. In addition, feed protein deamination is lowered, making it available for post-ruminal digestion and utilisation. These effects of monensin translate into a remarkable improvement in body weight gain in growing cattle and milk yield response in lactating cows. Thus, the augmented feed efficiency noted with iono­phores directly benefits farm economics. Besides, monensin attenuates some of the digestive disorders (bloat, acidosis, etc.) apart from enhancing energy status of cows in fresh lactation, leading to a lower risk for ketosis and displaced abomasum. This chapter presents a holistic overview of the modes of action, multifaceted benefits, economic returns, along with safety aspects of ionophore supplementation for a sustainable ruminant production. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.