Protein, Protease, and the Pathogen: Rethinking Campylobacter Control

Key takeaways

• Campylobacter jejuni is a major poultry-associated foodborne pathogen.
• High cecal Campylobacter jejuni increases processing contamination risk.
• Protein digestion shapes which bacteria thrive in the intestine.
• Better upper-gut digestion and absorption reduce nutrients available to Campylobacter jejuni.
• Jefo Protease improves amino acids digestion and absorption and strengthens intestinal integrity.
• Jefo Protease lowers harmful fermentation and reduces Campylobacter jejuni pressure.

Campylobacter jejuni in broilers

Campylobacter jejuni is frequently found in the poultry digestive tract and usually does not cause visible illness in birds. However, high levels in the cecum increase the likelihood of carcass contamination during processing. Reducing bacterial pressure before birds leave the farm remains an important objective for poultry producers.

Protein digestion shapes the gut environment

Protein digestion influences the gut environment primarily through the efficiency of amino acids and peptides absorption in the upper intestine rather than through the presence of intact proteins reaching the hindgut. Bacteria such as Campylobacter jejuni rely on free amino acids and small peptides, not whole proteins, as nutrient sources. When absorption in the upper intestine is suboptimal, higher concentrations of these substrates remain available further down the tract, supporting bacterial persistence. Improving protease activity upstream increases the release and uptake of free amino acids and small peptides, thereby reducing substrate availability in the lower intestine and helping shape a less favorable environment for pathogenic bacteria like Campylobacter jejuni.

Why better protein digestion can work against Campylobacter jejuni 

Campylobacter jejuni has limited ability to break down intact protein on its own. Instead, it depends on small amino acids and peptides that escape absorption earlier in digestion. When protein digestion is improved in the upper intestine, more of these nutrients are absorbed by the bird rather than passing into the lower gut. This leaves fewer resources available where Campylobacter jejuni typically establishes itself. 

Jefo Protease increases amino acid transporters and intestinal integrity barrier

Jefo Protease supplementation improves protein utilization by enhancing the release and absorption of free amino acids and small peptides in the upper intestine. University research has shown increased gene expression of amino acids and peptides transporters in different sections of the small intestine of animals supplemented with Jefo Protease. In broilers at 35 days of age, Jefo Protease supplementation increased jejunal occludin mRNA expression compared with both the positive and negative control groups, as shown in Figure 1. Occludin is a key tight junction protein, and higher expression reflects improved intestinal barrier integrity. Together, enhanced upstream nutrient absorption and a stronger epithelial barrier help limit substrate availability and bacterial translocation further down the intestinal tract, supporting overall gut health.

Reducing undesirable fermentation

When excess protein reaches the lower gut, it is fermented by potentially pathogenic bacteria, producing compounds such as ammonia and biogenic amines. These by-products can disrupt the gut environment and contribute to Campylobacter jejunigrowth. Protease supplementation has been shown to reduce these fermentation products, indicating that more protein is being used efficiently by the bird instead of fueling potentially pathogenic bacteria activity in the hindgut.

Campylobacter control prior to processing

Research conducted by the Montreal University Research Chair in Meat Safety and published in Gut Pathogens (2025) showed that improving protein digestibility through Jefo Protease supplementation can reduce Campylobacter jejuni pressure at key intestinal sites. Broilers receiving the protease-supplemented diet showed lower Campylobacter jejunilevels in the cecum, the primary intestinal reservoir, along with reduced Campylobacter jejuni dissemination to the liver early after colonization. Because high cecal loads and extra-intestinal spread are linked to contamination risk during processing, protein digestibility becomes an important consideration for Campylobacter jejuni control.

What this means in practice

Taken together, these findings highlight the importance of protein digestion as a practical way for managing Campylobacter jejuni pressure in broilers. By helping birds digest and absorb protein earlier, Jefo Protease supplementation limits nutrient availability in the lower gut, supports a better intestinal integrity barrier and reduces conditions that favor bacterial persistence. Used as part of an integrated production strategy, Jefo Protease can serve as a nutritional tool to support healthier birds and better-quality animal protein.