The use of antibiotics in livestock is indispensable to treat most infectious diseases that affect livestock. In addition to their therapeutic application, antibiotics have been used in livestock for preventive purposes and as growth promoters, but due to the emergence of resistant bacteria their use has been restricted to stimulate growth and prevent undiagnosed diseases. Faced with this situation, farmers are demanding alternative methods to reduce the use of antibiotics without reducing the profitability and quality of their production.
Currently there are multiple alternatives that allow to improve the health and well-being of animals among which are probiotics, prebiotics, enzymes, organic acids, and especially phytogenic compounds. Among the phytogenic products whose effectiveness has been more widely demonstrated by the research community are the derivatives of garlic and onion. Its use as medicinal plants dates back to the early days of humanity and in all known cultures.
There are numerous scientific studies in which it has been shown to be effective in treating various infections and parasites which together with their stimulating properties of the immune system and anti-inflammatory cause them to be considered among the compounds to promote animal health status and improve productive rates.
Alterations in the gut microbiota weaken the mucosa by allowing bacteria to easily pass through it. The organosulfur compounds (OSCs) present in garlic and onion exert direct action on the microorganisms attached to the intestinal epithelium, so their use in livestock has multiple advantages:
The antimicrobial action of OSCs has been widely demonstrated in many studies, proving highly effective in decreasing pathogenic bacteria of livestock interest such as Salmonella, E. coli, Brachyspira, etc. In addition, its mechanism of action is not only antibacterial but has a marked anti-parasitic action mainly against coccidia of the genus Eimeria, one of the main causes of economic losses on farms.
Fig 1. The excretion of oocysts in brooilers infected with coccidia is significantly lower in those animals that consume additive feed with the thiosulfonates present in Garlicon (Kim et al. 2012).
OSCs have been shown to act against enteropathogenic bacteria (Salmonella, E. coli, etc.) while respecting beneficial bacteria (Lactobacillus and Bifidobacterium), which contributes to proper fermentation absorption of its derivatives, such as volatile fatty acids, vitamins and minerals (Hairstyle et al., 2013).
Fig. 2. Evolution of the different bacterial groups at intestinal level during the fattening and finishing phase after the addition of Garlicon to the diet of weaned piglets (day 0) until the end of the fattening phase (day 103). A decrease of enterobacteria, clostridia and salmonella is observed, while lactobacilli and bifidobacteria are maintained or increased. (Sanchez et al. 2020). # P<0.010; * P < 0.05; **P< 0.01; ***P< 0.001
The use of the OSCs present in garlic and onion causes the increase of the absorption surface and thickness of the intestinal mucosa. This improvement influences a multitude of beneficial processes for the animal such as nutrient absorption, defense against external pathogens and correct inflammatory respons
Fig. 3. The mucosal state of the colon of mice with colitis that consumed Garlicon is similar to that of healthy mice (negative control), unlike those animals with colitis that did not consume it (positive control) (Vezza et al., 2018).
OSCs have the ability to inhibit excessive production of proinflammatory cytokines, reducing intestinal inflammation that causes dehydration, poor absorption of nutrients and the entry of pathogenic microorganisms.
In addition, this decrease in inflammation extends to other areas of the body, helping to prevent airway obstruction or inflammation of joints that limit the movement of the animal and food intake.
Fig. 4. Influence of OSCs on the production of pro-inflammatory cytokines in pig lung macrophages (Liu et al. 2012).
The principles assets present in garlic and onion has the ability to stimulate antibody production against specific antigens, stimulating this mode the immune system of the animal.
Fig. 5. Stimulation of antibody production against coccidia stimulated thanks to the action of the active substances present in the Garlicon (Kim et al. 2012).
The benefits of these compounds and their scientifically proven efficacy indicate that, of all existing phytogenic compounds, the use of Garlicon as an alternative to the use of antibiotics as preventive and growth promoters, is the right choice.