Plant Feed Additives as Natural Alternatives to the Use of Synthetic Antioxidant Vitamins on Livestock Mammals’ Performances, Health, and Oxidative Status: A Review of the Literature in the Last 20 Years

Abstract

In the last two decades, the interest in natural plant feed additives (PFA) as alternatives to synthetic vitamins in livestock nutrition has increased. After a systematic review, a total of 19 peer-reviewed papers published between 2000 and 2020 were retained to evaluate the antioxidant effects of PFA compared to synthetic antioxidant vitamins (mainly vitamin E; VitE) in livestock nutrition. These studies demonstrated that PFAs could be as efficient as VitE in counteracting oxidative stress in pigs, rabbits, and ruminants. However, PFAs only positively affected animals’ growth performance and feed efficiency in some monogastric studies. The PFA can affect antioxidant enzyme activity in a dose- and method of administration-dependent manner. The antioxidant capacity of both PFA and VitE were depressed in cows fed with diets rich in polyunsaturated fatty acids. Variability among studies could be related to species differences. Despite the interest of the feed industry sector in PFA, there are still very few studies evaluating their antioxidant effect in species other than poultry.

Intake of nutrients (polyunsaturated fatty acids, tocols, and carotenes) and storage efficiency in different slow-growing chickens genotypes reared in extensive systems

“…In SG6 and SG5, the intake of tocols was mainly furnished by feed. Indeed, tocopherol-acetate is generally added to the poultry diets to improve the shelf life of meat, [ 49 ], greatly contributing to the tocols furnished by feed.…”

Advances in the Application of Phytogenic Extracts as Antioxidants and Their Potential Mechanisms in Ruminants

“…Proanthocyanidins , one of the polyphenol compounds that are abundant in bearberry and green tea, has been proven to donate hydrogen atoms/electrons and to function as an antioxidant [ 39 , 40 ]). Second, with more hydroxyl groups present in the skeletons of plant extracts such as flavonoids, the plant extracts can potentially possess a higher capacity of antioxidants because they can provide more electrons [ 41 ]. Many studies have reported that phenolic compounds with higher hydroxylation, particularly those located ortho to one another (catechol moiety, namely, vicinal OH groups), exert extremely high antioxidant activities [ 42 , 43 ]).…”

Broiler Chickens' Growth, Haematological Indices, Guts Microbiota, Carcass and Meat Analysis in Response to Dietary Supplementation with Anacardium occidentale Leaf Powder and A Mix of Prebiotic, Probiotic and Acidifier

“…Co., Ltd. Seoul, Korea), the cholesterol concentrations were measured phytobiotics, and acidifiers have all been investigated as nutritional supplements to assist offset the detrimental effects of elevated environmental temperature and heat stress (Awaad et al, 2018;Awad et al, 2020). When used as dietary supplements, a variety of tropical botanicals or phytogens show antioxidant action (Manuelian et al, 2021;Oloruntola et a., 2022). Prebiotics has been associated with an increase in the beneficial microbial population, whereas probiotics have been connected to a reduction in antioxidative stress in animals (Zhang et al, 2011;Awad et al, 2020).…”