EC Microbiology

The massive and sometimes inappropriate use of antibiotics in livestock farming has encouraged the emergence of antimicrobial resistance (AMR), posing a major threat to animal, human and environmental health. In the global fight against AMR, the search for effective, safe and sustainable alternatives to antibiotics is becoming a priority. This review looks at three promising alternatives: phytotherapy, probiotics and organic acids.

Firstly, phytotherapy is based on the use of medicinal plant extracts with antimicrobial, anti-inflammatory, immunostimulant and antioxidant properties. Certain species, such as Azadirachta indica, Allium sativum and Thymus vulgaris, have been shown to be effective against a range of bacterial pathogens, while also boosting the intestinal health of animals. These plants therefore offer significant potential in the prevention and treatment of infectious diseases.

Secondly, probiotics, defined as live micro-organisms administered in adequate quantities, help to restore the balance of the intestinal microbiota, boost immune defences and reduce the adhesion of pathogens to the digestive mucosa. Strains such as Lactobacillus spp., Bacillus subtilis and Saccharomyces cerevisiae are commonly used in poultry and pig production. As a result, probiotics are perfectly suited to strategies for preventing digestive disease.

Organic acids such as formic, propionic or butyric acid have an acidifying effect in the digestive tract, inhibiting the growth of pathogenic bacteria while improving digestibility and zootechnical performance. Their use in animal feed is recognised for improving feed conversion rates and reducing digestive tract infections. They are therefore a complementary solution to phytotherapeutic and probiotic approaches.

Ultimately, these alternatives, alone or in synergy, offer concrete ways of reducing the use of antibiotics while maintaining farm productivity. However, their effectiveness depends on a number of factors, including formulation, dose, target animal species, administration method and rearing conditions. The review therefore stresses the importance of rigorous evaluation, based on sound scientific data, as well as support for farmers as part of integrated biosecurity programmes and good husbandry practices.

 Keywords: Antibiotics; Livestock Farming; Phytotherapy; Probiotics; Organic Acids

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