Necrotic enteritis is a persistent problem for poultry producers made even more challenging as antibiotics are being removed from production practices.
Caused by the bacterium Clostridium perfringens, necrotic enteritis has been estimated to impose an annual cost of US$2 billion on poultry producers worldwide. Many experts, however, believe the actual cost may be much higher because subclinical cases of necrotic enteritis in flocks are difficult to diagnose.
These costs are expected to rise. As growing concern about antimicrobial resistance prompts regulatory bodies to ban in-feed antibiotics, and as consumers demand more transparency when it comes to how their food is produced, poultry producers must find alternatives, or face an increase in cases of necrotic enteritis and consequent negative impacts on productivity.
While clinical necrotic enteritis may cause death within one to two hours and result in mortality rates of 50 percent, subclinical cases are harder to diagnose and can be chronic. Signs of subclinical necrotic enteritis include reduced weight gain, wet droppings and increased feed conversion ratios. All of these signs can negatively impact producers’ bottom lines.
Economic losses from necrotic enteritis on broiler farms is estimated to be in excess of US$2 billion annually. | Courtesy Trouw Nutrion.
How can producers address the performance consequences posed by subclinical necrotic enteritis in today’s production and regulatory landscape?
The following are five practical insights for rethinking approaches to support enteric health.
1. Organic acids
Feeding birds a synergistic blend of organic acids may achieve similar results to feeding antibiotic growth promoters. Studies have evaluated growth performance, health, carcass and the immune oxidative status of broilers fed a blend or organic acids under a C. pefringens Type A challenge, and found that, not only were results similar to birds fed antibiotic growth promoters, but that intestinal lesions in birds receiving organic acids were numerically lower compared to the challenge control group.
2. Three-pronged growth, performance approach
Replacing in-feed antibiotics with a combination of organic acids, hydroxy trace minerals and water acidification has been found to result in growth comparable to administering an antibiotic after disease challenge. Chicks administered this combination during the starter phase have also been found to have higher body weights than those receiving an antibiotic.
3. Boost sub-standard diets
While the nutrient density of poultry diets varies by geographic region, research has found that applying a combination of copper hydroxychloride and a synergistic feed additive to the sub-optimal diet may improve nutrient digestibility and allow broilers to grow at a similar rate to birds fed a standard diet.
A study comparing standard and sub-optimal diets with and without additives, found that, regardless of a diet’s nutrient density, broilers receiving copper hydroxychloride and a feed additive showed health and performance benefits comparable to birds receiving an antibiotic growth promoter.
4. Scoring to inform gut health approaches
Some signs of subclinical necrotic enteritis are easily observable. However, other indicators within birds’ GI tracts are not visible and can contribute to reduced growth.
Gut scoring can provide a broad overview of internal conditions affecting enteric health, such as redness of mucosa, consistency of gut content, feed passage and the severity of internal lesions. Gut scoring can also identify underlying issues that may compromise growth performance and provides a useful tool for comparing the enteric conditions of flocks and the efficiency of different interventions and products.
Gut scoring can help to assess the severity of necrotic enteritis lesions. | Courtesy Micronutrients
5. Feed-farm-health management
Despite their widespread use, antibiotics were never a panacea for gut health and their use resulted in unintentional consequences such as decreased diversity in gut microflora. Achieving optimal enteric health and performance requires management across the entire production chain including feed formulation, farm management such as water hygiene and farm biosecurity and health management to support microbial balance and gut integrity.
While producers can no longer address the necrotic enteritis threat with the same tools used for decades, farm and health management combined with alternative functional feed additives can support flock health, growth and performance.
Necrotic enteritis increasing in antibiotic-free broilers
