Cracking the “hidden killer” of broilers: A new report from China Animal Husbandry & Veterinary Medicine reveals a powerful gut‑protecting duo—benzoic acid and cinnamon essential oil.

The study used wheat. - Soybean meal-based diet + A The classic method of oral administration of Clostridium perfringens type A. NE Induction Model:

Test subjects: Three hundred one-day-old 817 broiler chickens were randomly divided into five groups.

Group Settings: CON group (control, no challenge), CP group (challenged, NE model), SLLEO-L / M / H groups (challenged + diet supplemented with 1000 / 2000 / 3000 mg/kg SLLEO)

Challenge protocol: Days 15–17: Administer 1 mL of Clostridium perfringens suspension (1×10⁹ CFU/mL) by gavage daily for 3 consecutive days.

Indicator Testing: Slaughtered at 35 days of age; intestinal morphology, pH, and cecal 16S rRNA microbiota were analyzed.

CP challenge resulted in a significant increase in ileal pH (6.84 → 7.32), whereas SLLEO intervention exhibited a dose-dependent decreasing trend:

Intestinal acidification is a key mechanism for inhibiting the colonization of Clostridium perfringens— pH The lower it is, the harder it is for pathogens to survive.

CP challenge significantly reduced cecal microbial diversity (Shannon ↓, Chao1 ↓, Simpson ↑); however, in the 3000 mg/kg SLLEO group, all indices returned to levels not significantly different from those of the CON group:

Shannon index: CP group 2.83 → SLLEO-H group 3.51 (restored to CON levels)

Chao1 index: CP group 301.52 → SLLEO-H group 378.92 (even slightly higher than CON)

Simpson index: CP group 0.13 → SLLEO-H group 0.07 (significantly reduced)

This means a high dose. SLLEO Not only can " Stop-loss " , and can further restore a more resilient gut microbiota.

Phylum level: Firmicutes ↑, Bacteroidetes ↓

CP infection caused the relative abundance of Firmicutes to plummet from 56.95% to 42.56%, while the Bacteroidetes/Firmicutes ratio surged from 0.51 to 0.99; in contrast, the SLLEO-H group achieved complete reversal:

Phylum Firmicutes: 61.24% (even higher than the CON group)

Phylum Bacteroidetes: 26.00% (returned to the normal range)

Bacteroidetes/Firmicutes ratio: 0.42 (better than the CON group’s 0.51)

Phylum level: Three major key bacterial phyla showed a significant rebound.

An interesting phenomenon: at the phylum level, the abundance of Bacteroidetes decreases, while at the genus level, the abundance of Bacteroides actually increases. This suggests that different genera within Bacteroidetes exhibit divergent responses to SLLEO—SLLEO may specifically promote the proliferation of beneficial Bacteroides genera while inhibiting other harmful ones.

Integrating multi-dimensional data, including intestinal pH, microbial diversity, and phylum- and genus-level microbial composition, benzoic acid combined with cinnamaldehyde essential oil (SLLEO) exerts a significant ameliorative effect on CP-induced necrotizing enteritis:

Lower the ileal pH to create an acidic environment unfavorable for pathogenic bacteria.

Enhance cecal microbial diversity and restore a stable microecological structure.

Optimize the gut microbiota composition and increase the abundance of beneficial taxa such as Firmicutes, Bacteroides, and Enterococcus.

The results of this experiment demonstrate that SLLEO exhibits a positive intestinal protective effect at various addition levels, with the effect being dose-dependent:

1000 mg/kg (low dose): It can effectively alleviate the elevation of intestinal pH and the decline in microbial diversity caused by Clostridium perfringens infection, making it suitable for routine prevention and for farming environments with low or moderate infection risk; it is an economical choice for daily intestinal health management.

2000 mg/kg (medium dose): It performs better in optimizing gut microbiota structure and promoting the proliferation of beneficial bacteria, making it suitable for broiler flocks that already exhibit mild NE symptoms or are in a high-risk stress period (such as feed changes, vaccinations, or exposure to high temperature and humidity).

3000 mg/kg (high dose): It demonstrates the most pronounced effects in restoring ileal pH, rehabilitating cecal microbiota diversity, and optimizing microbial community structure at the phylum and genus levels. It is recommended as a therapeutic intervention during periods of high Clostridium perfringens infection pressure, when NE symptoms are evident, or during outbreaks, helping poultry flocks rapidly re-establish intestinal microecological balance.

Pig farms can flexibly adjust the inclusion level within the range of 1,000–3,000 mg/kg, based on their specific disease pressure, husbandry management conditions, and economic considerations, to achieve precise disease control while reducing costs and improving efficiency.

The combination of benzoic acid and cinnamaldehyde essential oil, with its advantages of being pollution-free, residue-free, and synergistically effective, offers a new approach to the green control of NE in poultry. Further research is still needed in the future:

Applicability of SLLEO in broilers of different breeds and at different growth stages

The specific functional mechanisms of the genus Oceanobacillus in NE prevention and control

Combination strategies of SLLEO with other control measures, such as vaccines and probiotics

This study provides a solid theoretical basis for the use of the “acidifier + plant essential oil” compound formulation in poultry, and also offers a scientific solution to reduce reliance on antibiotics and promote green development in animal husbandry.

For more related content, please click the link below: Acidified Feed Solutions for Broilers (Part 1) 》, 《 Acidifying Agent Solutions for NE in Broilers (Part II) 》