2016-17 Rapid Ag: Investigating the Efficacy of Multiple Antimicrobial Interventions Against Salmonella Heidelberg Colonization in Turkeys

November 1, 2015

Principal Leader

Anup Kollanoor Johny


Department of Animal Science

Funding Awarded

  • 2016 Fiscal Year: $70,000
  • 2017 Fiscal Year: $64,958.51 

The Problem

Minnesota ranks no. 1 in the production of turkeys with 45 million turkeys produced in 2014. S. Heidelberg, one of the most invasive of all Salmonella serotypes, has surfaced to importance causing significant economic loss to poultry industry, including turkeys.


United States is the world’s largest turkey producer and the largest exporter of turkey products (AgMRC, 2015). Minnesota ranks no. 1 in the production of turkeys with 45 million turkeys produced in 2014 (NASS, 2014). Among the leading turkey processors in the United States, Jennie-O turkey store is the second largest processor of turkeys with 1.25 billion lbs. of meat processed each year. Most turkeys undergo further processing steps and ground turkey is an important area of product growth. The fact that ground turkey is a lower fat substitute for ground beef (AgMRC, 2015) invites tremendous consumer acceptance for the product. However, contamination of ground turkey with foodborne Salmonella has resulted in product recalls causing huge economic losses to the industry, historically (CDC, 2011a, b). Since turkeys can act as reservoir hosts for Salmonella and contaminate the environment and products, antimicrobial interventions that reduce the environmental load of the pathogen and product safety is urgently required. Despite several control efforts, Salmonella remains a major cause of foodborne outbreaks in the United States resulting in an annual estimated economic loss of $4.4 billion (Scharff et al., 2012; Scallan et al., 2011). Recently, USDA has proposed a performance standard designed to achieve at least 30% reduction in illness from Salmonella in poultry, including ground turkey (USDA, 2015).

Salmonella Heidelberg – an emerging problem: S. Heidelberg, one of the most invasive of all Salmonella serotypes, has surfaced to importance causing significant economic loss to poultry industry, including turkeys. In 2011, the consumption of contaminated ground turkey meat resulted in 136 human infections in 34 US states (CDC, 2011a). In 2013, multidrug resistant S. Heidelberg infections were linked to contaminated poultry products from Foster Farms in California (CDC, 2013). Yet another outbreak caused by S. Heidelberg was reported from a Tennessee Correctional Facility linked to the consumption of mechanically separated poultry meat (CDC, 2014). Historically, S. Heidelberg has been one of the commonest Salmonella associated with poultry (Jackson et al., 2013; Scharff, 2012; Zhao et al., 2002; Layton et al., 1997; CDC, 1996; Schonei et al., 1995; Bokanyi et al., 1990; Mahony et al; 1990; CDC, 1986; Snoeyenbos et al., 1969). In the 90s, S. Heidelberg was reported to cause an average of ~2100 infections annually accounting for 6% of all confirmed human Salmonella infections (Hennessy et al., 2004). Of the 20 Salmonella serotypes associated with human infections, five were commonly isolated from turkeys, the most frequently isolated being S. Heidelberg (Foley et al., 2007). Latest reports indicate that S. Heidelberg has become one of the three serotypes of poultry origin contributing to more than 80% human outbreaks (Jackson et al., 2013).

Problem of Salmonella in turkeys: Salmonella can colonize the intestinal tract of turkeys (Gruenberg, 2014, Kasbohrer et al., 2013, EFSA, 2008). The pathogen colonizes the ceca, two sac-like structures located between small and large intestines, from where it gets excreted outside, resulting in environmental contamination. In addition, meat may get contaminated with Salmonella during processing. Turkeys and turkey products have been implicated in Salmonella-associated outbreaks in the past (CDC, 2011, Cook et al., 2009, Foley et al., 2007; Fakhr et al., 2006), indicating a potential source-pathogen link (Salmonella – turkeys link). Infected turkeys on farms can be critical sources for Salmonella contamination in turkey meat and products (Rostagno et al., 2006). In addition to birds, there are multiple sources for Salmonella on farms including bedding, drinkers, feed, box liners, yolk sac, ceca, feed shipments, and air (Nayak et al., 2003; Hoover., 1997). Salmonella has been isolated from ground turkey meat in a range of 19% to 60% from American processing facilities during 1996-2006 (Zhao et al., 2008). Studies indicate that ground turkey samples have been contaminated with Salmonella from 20.3 to 26.4% (White et al., 2007). In a US study, Rostagno and coworkers observed a higher overall prevalence of Salmonella in six Midwestern turkey farms (33.3%), the contamination levels being similar in birds on farms and processed meat from those birds (Rostagno et al., 2006), indicating that contamination in meat could have originated from turkeys on farms. 


  1. To determine the efficacy of combined treatment of vaccination, direct fed microbials (DFM) of turkey origin (probiotics) and prebiotics on Salmonella Heidelberg in turkey hens.

  2. Disseminate project results to turkey growers and general public.