Strategies to control Salmonella in Poultry Farms
Salmonella is one of the most widely found bacteria in poultry farms across the world. Salmonella colonization can cause major infections and lead to severe economic losses. Earlier in India it was a taboo to accept the presence of Salmonella in flocks which lead to lack of awareness, acceptance and thus farmers were unable to diagnose or detect the cases of Salmonella. Recent rampant usage of antibiotics to control Salmonella has led to the development of increase of antimicrobial resistance strains of Salmonella. However, with increased awareness about food safety, poultry farmers are looking forward to new technologies and are in search of alternative means to control the problem of Salmonella to have better food safety and sustainable business, which will improve their reputation and set new standards of poultry farming.
An integrated and holistic approach that focuses on farm, feed and health management can protect birds from Salmonella infection and lower its load in poultry produce, thereby supporting the feed-to-food safety efforts of farmers. Good farm management practices and targeted medication programs will help to control Salmonella prevalence in the farm.
Several monitoring programs have detected a wide variety of Salmonella serotypes in layer, breeder and broiler feed. They can often be traced back to feed raw material contaminated by Salmonella. Maintaining proper hygiene of all the feed raw material and final feed is a key to a successful Salmonella control program.
In mash or pellet feed preparation, the temperature plays a vital role to control Salmonella & reduces the moisture in feed. The presence of moisture in feed may lead to fungal growth and provides a favorable environment for the growth of Salmonella. In Pelleting, the temperature reaches upto 85-900 C where the Salmonella gets killed due to high temperature, which should be preferred. But farmers usually prefer conventional mash feed which does not fulfil these conditions mainly due to lack of awareness and low exposure to advanced technology as pelleting involves high investment.
In order to address the economic challenges, we need to combine chemical decontamination with pelleting process for effective reduction in Salmonella levels. It will contribute to an improved, economical & hygienic feed . Chemical decontamination is the best way to reduce the microbiological load of the feed. Formaldehyde is particularly effective in reducing the levels of Salmonella in poultry feed. SCFA based products are also excellent alternatives to reduce the Salmonella load in the feed.
Recontamination after pelleting can also impair feed hygiene. The best way to avoid cross contamination is to follow standard pest control practices, ensure proper segregation, dust control & safe transport systems. The addition of chemical compounds like organic acids in the poultry feed can reduce the risk of contamination.
Farm management practices
To control the transmission of Salmonella within broiler, layer and breeder operations, poultry farmers must follow and maintain proper hygiene practices. Routine testing in the flock needs to be conducted to mitigate the risk of Salmonella in the farm.
Salmonella spreads not only through feed, but also drinking water and equipment. Reducing the microbiological load of the drinking water and preventing the formation of biofilms are necessary. Chlorination is the most used water sanitization technique while acidification with organic acids helps reduce the pH of drinking water supply and support water hygiene in the absence or presence of chlorine. If applied properly, both these techniques together are very effective for control of Salmonella in drinking water. Biofilms in the drinking water supply are another reservoir for Salmonella and are a continuous source of contamination. Chemical/mechanical cleaning and regular flushing can help remove and prevent biofilm formation.
The primary route of Salmonella infection is through fecal transmission. Unfortunately, specific drinking water/feed additives can complicate the process of colonization and invasion. Low acid strength short chain fatty acids strengthen the lower pH barrier of the upper gut and the mucosal barrier in the lower gut. High acid strength short chain fatty acids make it more challenging in the non-acidic areas of the gut.
Non-digestible oligosaccharides are complex carbohydrates that maintains the gut microbiota with beneficial effect on normal microflora and causes competitive exclusion of harmful pathogens including Salmonella. Some oligosaccharides have a high binding affinity to the fimbriae of gram negative bacteria, including Salmonella, which reduces their ability to colonize in the intestine. Some short chain fatty acids can downregulate Salmonella virulence and reduce their intestinal invasion.
Bacteriophage feed additives
Innovative phage-based feed additives are the most advanced way to prevent harmful bacterial infection in poultry. They selectively target and eliminate the specific bacteria, without negatively impacting the balance of the birds’ gut microflora. They have no side effects, are natural, non-GMO, and biodegradable. They can be easily applied through the water system, and top-of-the-line products like BAFASAL+G which are designed to control Salmonella, improve gut health, support production performance and reduce the unnecessary use of antibiotics. The current climate calls for producing better quality poultry produce with best farming practices that can help reduce the economic losses and reputational risks of pathogenic outbreaks, the addition of improved feed additives like bacteriophages will form a part of healthy and safe farm management practices