Review: In vivo and postmortem effects of feed antioxidants in livestock: a review of the implications on authorization of antioxidant feed additives

Abstract

The pivotal roles of regulatory jurisdictions in the feed additive sector cannot be over-emphasized. In the European Union (EU), antioxidant substances are authorized as feed additives for prolonging the shelf life of feedstuffs based on their effect for preventing lipid peroxidation. However, the efficacy of antioxidants transcends their functional use as technological additives in animal feeds. Promising research results have revealed the in vivo efficacy of dietary antioxidants for combating oxidative stress in production animals. The in vivo effect of antioxidants is significant for enhancing animal health and welfare. Similarly, postmortem effect of dietary antioxidants has been demonstrated to improve the nutritional, organoleptic and shelf-life qualities of animal products. In practice, dietary antioxidants have been traditionally used by farmers for these benefits in livestock production. However, some antioxidants particularly when supplemented in excess could act as prooxidants and exert detrimental effects on animal well-being and product quality. Presently, there is no exclusive legislation in the EU to justify the authorization of antioxidant products for these in vivo and postmortem efficacy claims. To indicate these efficacy claims and appropriate dosage on product labels, it is important to broaden the authorization status of antioxidants through the appraisal of existing EU legislations on feed additives. Such regulatory review will have major impact on the legislative categorization of antioxidants and the efficacy assessment in the technical dossier application. The present review harnesses the scientific investigations of these efficacy claims in production animals and, proposes potential categorization and appraisal of in vivo methodologies for efficacy assessment of antioxidants. This review further elucidates the implication of such regulatory review on the practical application of antioxidants as feed additives in livestock production. Effecting these regulatory changes will stimulate the innovation of more potent antioxidant products and create potential new markets that will have profound economic impacts on the feed additive industry. Based on the in vivo efficacy claims, antioxidants may have to contend with the legislative controversy of either to be considered as veterinary drugs or feed additives. In this scenario, antioxidants are not intended to diagnose or cure diseases as ascribed to veterinary products. This twisted distinction can be logically debated with reference to the stipulated status of feed additives in Commission Regulation (EC) No 1831/2003. Nonetheless, it is imperative for relevant stakeholders in the feed additive industry to lobby for the review of existing EU legislations for authorization of antioxidants for these efficacy claims.

Milk somatic cells, factors influencing their release, future prospects, and practical utility in dairy animals: An overview

“…Antioxidants (both vitamins and minerals) protect the body from damage by the free radicals and have been used both in humans and animals to prevent or delay cell damage. The supplementation of dairy cows having high SCC with antioxidant vitamins such as Vitamin A, C, and E and β-carotene as well as antioxidant minerals such as selenium, zinc, and copper is very effective in reducing their SCC, normalizing their milk composition, and ensuring an early recovery from mastitis [ 80 , 85 , 112 , 113 ]. Supplementation of inorganic selenium reduced IMI in S. aureus -infected dairy cows as compared to non-supplemented animals [ 114 ].…”

Citrus and Winery Wastes: Promising Dietary Supplements for Sustainable Ruminant Animal Nutrition, Health, Production, and Meat Quality

“…Inclusion of citrus and winery by-products below 200 g/kg DM in ruminant diets has been reported to reduce the occurrence of parakeratosis and acidosis in ruminants [13,63]. However, when elevated levels of citrus pulp were fed, along with low levels of forage, rumen parakeratosis and acidosis occurred in lambs [13].…”

Modulation of ruminal and intestinal fermentation by medicinal plants and zinc from different sources

“…Screening plant species has found that bioactive compounds in medicinal plants can also decrease ruminal methane emissions (Bodas et al, 2008(Bodas et al, , 2012Patra, Kamra, & Agarwal, 2006;Patra & Saxena, 2010). Botanicals rich in polyphenols comprise a structurally diverse class of natural products with antioxidative and antiinflammatory effects in farm animals (Augustyniak et al, 2010;Gessner, Ringseis, & Eder, 2017;Salami et al, 2016). In ruminants, using high-concentrate diets that are high in starch and low in fibre can reduce ruminal pH and cellulolytic activity in various metabolic disorders (Alzahal, Kebreab, France, & McBride, 2007;Krause & Otzel, 2006;Owens, Secrist, Hill, & Gill, 1998).…”