Using Beneficial Bacteria to Improve Antibiotic-Free Turkey Performance

Photo: iStockphoto_Mark Kokkoros

The poultry industry has gone through some tremendous changes recently, including genetic improvements, preventive disease control, increased biosecurity measures and the introduction of modern intensive production methods. The changes have been implemented due to increased demand for animal protein. From 1990 to 2005, the consumption of poultry meat increased by 35 million tons in developing countries (Narrod et al., 2007). In some countries where the production of red meat is not suitable, turkey meat has been a well-accepted replacement. However, its production, as with any other livestock sector, comes with complex challenges such as the need to enhance growth performance, nutrient absorption and to reduce enteric bacterial diseases.

Doing more with less antibiotics

Enhanced growth and feed efficiency are relevant topics for any turkey grower. In many places, reliance on nonmedically important poultry antibiotics has been essential to keep up with rising demand for safe and affordable animal protein. However, increasing pressure from consumers, food retailers and regulators has spurred the reduction of antibiotic usage in farm animals. Furthermore, the development of resistant pathogenic bacterial strains to certain antibiotics may jeopardize the effectiveness of antibiotics when treatment is needed. Already, an increase in susceptibility to some infections through immunosuppression or through the alteration of the gut microbiota has been observed (National Research Council, 1980).

A boost from beneficial bacteria

To counteract the undesired effects of antibiotic growth promoters (AGPs) and to reduce the use of antibiotics overall, novel feed additives and preventive drugs have been developed, such as phytogenics, organic acids, probiotics, prebiotics, synbiotics (combined probiotic plus prebiotic), and vaccines, that offer alternatives to promote animal performance and prevent health issues. PoultryStar® is a well-defined, multi-species synbiotic product that promotes a beneficial gut microflora through the combined action of carefully selected species-specific probiotic microorganisms and prebiotic fructooligosaccharides derived from inulin. It was designed to improve gut health and make chicks more resistant to pathogenic infections, while also achieving enhanced performance.

Antibiotic-free turkey trial in the US

In a scientific experiment in the United States with 540 poults (Koch's turkey hybrid) conducted over 98 days, the synbiotic PoultryStar® sol from BIOMIN was used in drinking water at a dose of 20g/1000 birds/day in combination with the commercial antibiotic-free (ABF) diet. The additive was applied in days 1-3, 7, 13-15, 21, 28, 35, 41-43, 49, 56, 63, 69-71, 77, 84 and 91 (first three days, every three days, around feed change and once a week). The control flock was administered only the commercial ABF diet, devised to support the marketing of “naturally fed” turkeys whose organic diets were free from animal protein products and antibiotics.

Trial results

The results of the trial show that PoultryStar® sol improved turkey performance. Final live weight was significantly higher (P<0.05) in the PoultryStar® group compared with the negative control (Figure 1). At 98 days of age, the supplemented birds achieved 9.120kg compared to 8.604kg in non-supplemented birds, a significant difference of 516g. Feed intake was 8% greater in the supplemented group, which may partly explain the achieved weight at the end of the trial (Figure 2). The feed conversion ratio (FCR) was not statistically different between the two groups.

Figure 1. Body weight per hen

Body weight per hen

Figure 2. Compilation of overall feed intake and FCR

Compilation of overall feed intake and FCR 

Related findings in chicken

These findings have also been confirmed in multiple scientific, commercial and field trials in broilers. A recent study found that the synbiotic PoultryStar® was able to improve intestinal histomorphology (Palamidi et al., 2016), which in turn improves digestibility due to an improved digestive function. Probiotics may induce enhancements in intestinal architecture forming an increased surface area, which may contribute to a greater absorption of nutrients (Awad et al., 2009). However, this must be confirmed specifically for turkeys with further studies.

Furthermore, trials in chickens have shown that the early prophylactic supplementation of PoultryStar® improves immune response of the birds, evidenced in peer reviews. PoultryStar® considerably reduced the incidence of pathogenic diseases, such as Salmonella Enteritidis in cecal content (Sterzo et al., 2007), decreased lameness attributable to bacterial chondronecrosis (Wideman et al., 2012) and enhanced performance and provided an additional protective effect against a mixed Eimeria challenge (Ritzi et al., 2016).


Scientific studies and trials have highlighted the benefits of using natural growth promoters, such as a synbiotic that includes a mix of probiotic strains and a prebiotic. This makes them an interesting tool in antibiotic-free feeding programs or in conventional operations as feed supplements to improve gut health and achieve better overall flock performance.

In Brief
  • Pressure from consumers is fueling the reduction of antibiotic use in turkey production
  • Without antibiotics, a performance gap opens up
  • Supplementing the diet with feed additives can help to close the performance gap
  • Feed intake and final body weight increased when PoultryStar® was added to the diet

Note: At time of writing, PoultryStar® has EU authorization for use in feed or water for chickens for fattening, chickens reared for laying and minor avian species to the point of lay. PoultryStar® is under evaluation for EU authorization for use in turkeys.


Awad, W., Ghareeb, K., Abdel-Raheem, S. and Bohm, J. (2008). Effects of dietary inclusion of probiotic and synbiotic on growth performance, organ weights, and intestinal histomorphology of broiler chickens. Poultry Science, 88(1), pp.49-56.

Narrod, C., Tiongco, M. and Costales, A. (2007). Global poultry sector trends and external drivers of structural change. FAO. Online. Available from: bangkok2007/docs/part1/1_1.pdf [Accessed 12.01.18].

National Research Council. (1980). The Effects on Human Health of Subtherapeutic Use of Antimicrobials in Animal Feeds. National Research Council, Commission on Life Sciences. Committee to Study the Human Health Effects of Subtherapeutic Antibiotic Use in Animal Feeds. Division on Earth and Life Studies and Division of Medical Sciences. National Academies Press.

Palamidi, I., Fegeros, K., Mohnl, M., Abdelrahman, W., Schatzmayr, G., Theodoropoulos, G. and Mountzouris, K. (2016). Probiotic form effects on growth performance, digestive function, and immune related biomarkers in broilers. Poultry Science, 95(7), pp.1598-1608.

Ritzi, M., Abdelrahman, W., van-Heerden, K., Mohnl, M., Barrett, N. and Dalloul, R. (2016). Combination of probiotics and coccidiosis vaccine enhances protection against an Eimeria challenge. Veterinary Research, 47(1).

Sterzo, E., Paiva, J., Mesquita, A., Freitas Neto, O. and Berchieri Jr, A. (2007). Organic acids and/or compounds with defined microorganisms to control Salmonella enterica serovar Enteritidis experimental infection in chickens. Revista Brasileira de Ciência Avícola, 9(1), pp.69-73.

Wideman, R., Hamal, K., Stark, J., Blankenship, J., Lester, H., Mitchell, K., Lorenzoni, G. and Pevzner, I. (2012). A wire-flooring model for inducing lameness in broilers: Evaluation of probiotics as a prophylactic treatment. Poultry Science, 91(4), pp.870-883.