Introduction

Why it matters in modern poultry production
– Rapid multiplication of Eimeria can produce substantial intestinal injury within a short period.
– Subclinical coccidiosis may reduce feed efficiency, growth and flock uniformity without dramatic clinical signs.
– High oocyst contamination of litter increases exposure and repeated infection pressure.
– Effective control requires attention to parasite biology, farm management and appropriate anticoccidial programmes.

Etiology
Seven major Eimeria species are recognized in chickens. E. acervulina and E. maxima are frequently encountered, while E. tenella is particularly pathogenic and associated with severe caecal disease and haemorrhage (Yaqub et al., 2023). Species differ in preferred intestinal sites, lesion patterns and pathogenicity.

Transmission
The principal route is faecal–oral transmission. Birds ingest sporulated oocysts from contaminated litter, feed, water, equipment or the environment. Moisture, oxygen and suitable temperature favour sporulation, allowing infective oocysts to accumulate and maintain the infection cycle (Pal et al., 2023).
Life Cycle of EIMERIA

Ingestion of sporulated oocysts → release of sporozoites → epithelial invasion → multiplication → gamete formation → oocyst formation → faecal shedding → environmental sporulation.

Clinical Signs
Severity depends on Eimeria species, infective dose, bird age, immunity and environmental management. Signs include reduced feed intake, depression, ruffled feathers, drooping wings, enteritis, diarrhoea or dysentery, poor growth and increased mortality in severe cases (Pal et al., 2023).
– Reduced body-weight gain and flock uniformity
– Poor feed conversion and production performance
– Diarrhoea or blood-stained droppings in severe infections
– Dehydration, weakness and depression
– Mortality when tissue damage and blood loss are extensive
Species-specific sites

Post-Mortem Lesions
Post-mortem examination helps identify likely Eimeria species and estimate the distribution and severity of intestinal damage. Lesion patterns should be interpreted with clinical findings, litter condition, performance data and, where appropriate, laboratory diagnosis (Pal et al., 2023; Yaqub et al., 2023).

Key lesion patterns

Prevention and Control
Effective control integrates anticoccidial programmes with litter management, hygiene, stocking-density control, ventilation and sound flock management. Continuous or inappropriate use of a single anticoccidial can contribute to reduced efficacy and resistance selection; rotation, shuttle programmes, combinations and vaccination are among approaches used for longer-term control (Usman et al., 2011; Chapman, 2017; Noack et al., 2019).

Anticoccidial programmes
– Rotation changes the active ingredient or mode of action between production cycles.
– Shuttle programmes use different anticoccidial strategies during different feed phases.
– Combination programmes can broaden anticoccidial activity and may help address reduced sensitivity when appropriately designed (Chapman & Rathinam, 2022).
– Vaccination can provide controlled exposure to selected Eimeria strains and support protective immunity.

Ionophore vs Chemical

Combination programmes
Combining compatible anticoccidial activities can broaden control and reduce dependence on a single mode of action. Programme selection should consider disease pressure, previous anticoccidial history, susceptibility patterns, compatibility and label requirements (Chapman & Rathinam, 2022).

STALLEN’S DUAL APPROACH TO COCCIDIOSIS CONTROL
Stallen South Asia offers a dual approach to coccidiosis management with Manacox Plus, bringing together ionophore and chemical anticoccidial activity in one formulation. This approach is designed to support practical, structured coccidiosis-control programmes while reducing dependence on a single mode of action.

MANACOX PLUS
Manacox Plus is a dual-active anticoccidial formulation combining an ionophore and a chemical anticoccidial. It contains Monensin Sodium 8% + Nicarbazin 8% for practical coccidiosis prevention programmes in broilers.
Key Product Points

WHY A DUAL APPROACH
Using monensin sodium together with nicarbazin brings ionophore and chemical anticoccidial activity into one formulation. This can fit structured prevention programmes where the objective is effective control without unnecessary reliance on a single mode of action. Use should follow the approved label and veterinary guidance.
Practical use
– Use within a planned farm coccidiosis-control programme.
– Maintain good litter quality, ventilation, stocking density and drinker management.
– Review anticoccidial history and flock response when planning future programmes.
– Follow approved dose, withdrawal period and compatibility instructions.

References are available on request.

Introduction

Gut: The First Line of Immune Defence
The intestinal defence system consists of several interconnected components, including the mucus layer, intestinal epithelial cells, tight junctions, antimicrobial substances, gut microbiota and gut-associated lymphoid tissue (GALT).

The epithelial cells form a physical barrier between the intestinal contents and the internal tissues. Tight-junction proteins such as occludin, claudins and ZO-1 regulate the movement of substances between epithelial cells. The mucus layer provides an additional protective environment, while immune cells located within and beneath the intestinal mucosa continuously monitor microbial and dietary antigens.
Thus, the intestine acts as both a selective absorption system and an immune surveillance system.

Gut Microbiota and Immune Development
The intestinal tract contains a complex microbial ecosystem. A balanced microbial population can contribute to pathogen exclusion, production of microbial metabolites, maintenance of intestinal integrity and modulation of host immune responses.
Beneficial microorganisms and their metabolites communicate with intestinal epithelial cells and immune cells. Among these metabolites, short-chain fatty acids (SCFAs) such as acetate, propionate and butyrate are particularly important because they can influence epithelial health, immune-cell activity and inflammatory responses. Therefore, gut microbiota and immunity have a bidirectional relationship. A healthy microbiota supports a healthy intestinal barrier and balanced immune signalling. At the same time, the immune system regulates microbial populations and helps maintain intestinal homeostasis.
What Happens When Gut Health Is Compromised?
Commercial poultry are exposed to several factors capable of disturbing gut integrity, including coccidiosis, bacterial pathogens, mycotoxins, heat stress, poor water quality, nutritional imbalance and dysbiosis.

A compromised gut can result in epithelial damage, disruption of tight junctions, increased intestinal permeability, inflammation and oxidative stress, altered immune response and reduced performance. This process is sometimes described as increased “intestinal permeability” or “leaky gut.”

When intestinal integrity is compromised, nutrients may not be utilized efficiently and microbial products can interact more extensively with host immune mechanisms. The bird may consequently spend additional nutrients and metabolic resources on inflammation and tissue repair rather than growth or egg production.

Coccidiosis, Mycotoxins and Heat Stress

Coccidiosis is a classic example of the gut–immune relationship. Eimeria infection damages intestinal epithelial cells, alters intestinal morphology and stimulates an inflammatory and immune response. Consequently, coccidiosis control is not only a parasite-management issue but also a gut health, nutrition and immune-management issue.

Similarly, mycotoxins can affect intestinal integrity, oxidative status, microbial balance and immune function. Their impact may therefore extend beyond the feed itself to the overall gut–immune axis.

Heat stress is particularly important in tropical poultry production. Heat stress can alter feed intake, intestinal physiology, microbial balance and barrier integrity, potentially increasing inflammatory and oxidative stress. Maintaining gut integrity during heat stress is therefore an important component of maintaining flock resilience.

Gut Health and Vaccine Response
An effective vaccination program depends on the bird’s ability to recognize antigens and develop appropriate humoral and cellular immune responses. This requires adequate availability of energy, amino acids, vitamins, minerals and antioxidants. Therefore, gut health indirectly supports the nutritional foundation required for immune responses. A healthy intestine facilitates nutrient digestion and absorption, while intestinal inflammation or damage can increase nutrient requirements for tissue repair and immune activity. It is important, however, to recognize that good gut health alone does not guarantee vaccine success. Vaccine quality, administration, maternal immunity, biosecurity, disease pressure, nutrition and environmental conditions also influence the final immune response.

Nutritional Support for the Gut–Immune Axis
Nutrition is one of the most important tools for supporting the gut–immune relationship. Zinc contributes to epithelial integrity, cellular proliferation, enzyme activity and immune-cell function. Selenium is an important component of antioxidant defence systems and supports cellular protection and immune function. Vitamins A and E also contribute to mucosal integrity, antioxidant protection and immune responses.
Nutritional interventions such as probiotics, prebiotics, postbiotics, organic acids, enzymes, yeast-derived products, MOS and β-glucans may be used as part of integrated gut-health programs. MOS can support gut health through microbial interactions and pathogen-exclusion mechanisms, while β-glucans can interact with innate immune pathways and influence immune-cell activity. However, responses depend on product source, structure, dose, bird age, diet and challenge conditions; therefore, these products should be evaluated based on scientific evidence and field performance rather than assuming that all products have identical effects.

Practical Approach for Commercial Poultry
A successful gut-health program should not depend on a single feed additive. It should combine:
– High-quality and properly stored feed
– Regular mycotoxin monitoring and management
– Good drinking-water quality and sanitation
– Effective coccidiosis control
– Appropriate vaccination and biosecurity
– Heat-stress management
– Balanced amino acid, vitamin and mineral nutrition
– Appropriate use of probiotics, prebiotics/postbiotics and other gut-health products
– Monitoring of litter quality, feed intake, FCR, mortality and flock uniformity

Conclusion
The gut and immune system should be viewed as two interconnected components of the same biological defence network. A healthy intestinal microbiota, intact epithelial barrier and properly functioning GALT provide the foundation for balanced immune development and response. For commercial poultry, the concept is simple: “Protect the gut to support immunity, and support immunity to maintain flock resilience.”
Gut health is therefore not only about digestion and FCR. It is closely connected with nutrient utilization, immune development, disease resistance, vaccine responsiveness and ultimately flock productivity.
The future of poultry nutrition will increasingly focus on managing the gut–microbiota–immune axis through integrated nutrition, health and farm-management strategies rather than addressing individual problems in isolation.

FERMNUTRAL: A POSTBIOTIC INNOVATION TO MAXIMIZE GUT HEALTH AND EFFICIENCY IN POULTRY PRODUCTION

Gut Health: The Key to Modern Poultry Production
The expression of the genetic potential of poultry largely depends on intestinal health. The gastrointestinal tract houses nearly 70% of the immune cells and constitutes the primary barrier against enteric pathogens. However, during the early stages of life, immune immaturity increases susceptibility to infections and microbiota imbalances, particularly under intensive production systems.

Traditionally, antibiotic growth promoters (AGPs) have been used to improve productive performance and reduce health-related challenges. However, their continuous use has been associated with antimicrobial resistance, intestinal dysbiosis, and concerns regarding food safety and public health.

In this context, postbiotics have emerged as a sustainable alternative. They are defined as preparations of inanimate microorganisms and/or their bioactive components, including short-chain fatty acids, bacteriocins, exopolysaccharides, peptides, and cell

wall fragments. Unlike probiotics, postbiotics offer greater stability, safety, and consistency, making them an effective alternative to AGPs (Zhong et al., 2022).

Postbiotics vs. Probiotics: A Real Competitive Advantage
The probiotics most commonly used in poultry production, such as Lactobacillus spp. and spore-forming Bacillus spp., present certain limitations when compared with postbiotics.

Lactobacillus species are heat-sensitive microorganisms; therefore, their survival during feed pelleting and storage may be compromised. In addition, factors such as chlorination of drinking water can reduce their viability and, consequently, their biological efficacy.

In contrast, Bacillus spp. exhibit high resistance to elevated temperatures due to spore formation. However, their beneficial effects may depend on successful intestinal germination and on the physiological and microbiological conditions of the host. Furthermore, these bacteria do not permanently colonize the gastrointestinal tract, meaning that their biological impact may depend on continuous administration through feed or drinking water.

Postbiotics exhibit high stability during feed processing and storage, as well as in chlorinated drinking water, because they do not rely on cell viability. Moreover, their bioactive compounds can exert their effects immediately upon ingestion, without requiring germination or intestinal colonization. This allows for a faster, more reproducible, and more consistent response (De Marco et al., 2018).

FermNutral: Bioactive Profile of a Full-Spectrum Postbiotic
FermNutral is a postbiotic developed and manufactured by CPBIO through the controlled biological fermentation of the Clostridium butyricum CPBIO3000 strain using natural raw materials. (Figure1)

The product is supplied as granules with demonstrated stability at temperatures exceeding 80°C (simulating the feed pelleting process). The recommended inclusion rate for poultry is 300–500 g/t of feed. FermNutral is produced under FAMI-QS, FDA-cGMP, and ISO 9001/14001/18001 certifications, which have been maintained since 2001.

FermNutral contains a diverse range of bioactive compounds generated during the fermentation process, including teichoic acids, lipoteichoic acids, butyricin, antimicrobial peptides, and exopolysaccharides.

Within its short-chain fatty acid (SCFA) fraction, butyric acid represents approximately 40% of the total SCFAs. Other SCFAs are present at lower concentrations, including acetic acid (21.6 mg/kg) and propionic acid (81.6 mg/kg).
The vitamin fraction includes vitamin E (13.9 IU/kg), vitamin B1 (17.2 mg/kg), vitamin B2 (5.08 mg/kg), vitamin B5 (57.3 mg/kg), vitamin B6 (98.3 mg/kg), vitamin B12 (0.34 mg/kg), folic acid (30.9 mg/kg), and vitamin K3 (1.97 mg/kg). The mineral profile provides calcium (15.2%), total phosphorus (0.76%), iron (760 mg/kg), zinc (42 mg/kg), magnesium (3,600 mg/kg), and chromium (11.67 mg/kg). Additionally, FermNutral contains 17 amino acids, including glutamic acid (1.37%), alanine (0.59%), valine (0.46%), leucine (0.50%), and lysine (0.29%). Altogether all amino acids are between 10-12% in product.

This unique combination of bioactive metabolites, nutrients, vitamins, minerals, and amino acids supports intestinal integrity, microbial balance, immune function, and productive performance in poultry.

Figure 1: A postbiotic product derived from biological fermentation of Clostridium butyricum CPBIO3000 using natural raw materials

FermNutral: Bioactive Compounds
FermNutral contains a wide range of bioactive compounds generated during the fermentation process, with butyric acid being the predominant short-chain fatty acid (SCFA), representing approximately 40% of the product. Butyrate serves as a major energy source for enterocytes and promotes epithelial renewal, mucin synthesis, and the expression of tight junction proteins. These effects contribute to maintaining intestinal barrier integrity and reducing intestinal permeability.
In addition, butyrate exhibits immunomodulatory and anti-inflammatory properties through its ability to regulate epigenetic processes, promote goblet cell differentiation, and stimulate the activation of regulatory T lymphocytes. It may also enhance intestinal serotonin release, which has been associated with the gut-brain axis and productive performance. Acetic and propionic acids complement these effects by regulating the intestinal environment and inhibiting undesirable microorganisms.

FermNutral also provides teichoic acids and lipoteichoic acids, which are recognized by Toll-like receptor 2 (TLR-2) on the intestinal mucosa. These components modulate both innate and adaptive immune responses, promoting a balance between immune defense and tolerance while helping to control intestinal inflammation (Pasquina et al., 2013; Muhammad et al., 2021).

Furthermore, FermNutral supplies butyricin (a bacteriocin), bioactive peptides, and antimicrobial peptides produced during fermentation, which contribute to the control of undesirable microorganisms and the modulation of intestinal microbiota. Exopolysaccharides are also present and have been reported to stimulate secretory IgA production and strengthen the mucosal barrier. In addition, the product’s vitamin and mineral profile acts synergistically to support immune function, antioxidant status, intestinal integrity, and productive performance.

FermNutral in poultry production
Several experiments conducted in China and Thailand have demonstrated the efficacy of FermNutral in poultry production. In a study at Guizhou University (China) comparing a control diet with additives such as FermNutral, Clostridium butyricum, protected sodium butyrate, and tributyrin in broiler chickens, the postbiotic (FermNutral) was confirmed to improve weight gain (+13%) and reduce feed conversion ratio (-11.68%) compared with the control and other experimental treatments.

In addition, another experiment carried out in a commercial broiler farm in China found that FermNutral reduced the feed conversion ratio (1.73 vs 1.77) and improved viability (+1.94) and the European Production Efficiency Factor (EPEF; 338.70 vs 315.30) in relation to the control diet.
Likewise, in a commercial broiler farm in Thailand, the use of FermNutral increased weight gain (+4.2%) and EPEF (+11.70%) and reduced feed conversion ratio (-7.69%). Furthermore, other trials conducted at Guizhou University (China) showed that FermNutral increased villus height in the duodenum (+9%), jejunum (+4%), and ileum (+8%), and improved the villus height to crypt depth ratio (V/C) in the duodenum (6.92 vs 6.27) and jejunum (5.71 vs 5.04).

Figure 3 : FermNutral effect on Immunoglobulins

Additional results from this experiment reported that FermNutral decreased the population of Escherichia coli in the duodenum (0.014 vs 0.234) and jejunum (0.0004 vs 0.013). Moreover, it promoted the growth of Lactobacillus in different intestinal segments, as determined by the relative abundance of microorganisms through 16S rDNA sequencing. (Figure 2) Finally, the inclusion of FermNutral in the diet improved the concentration of IgA (+13%), IgG (+19%), and IgM (+24%) compared with the control diet. (Figure 3)

Figure 2 : 16S rDNA sequencing to determine relative abundance of microorganisms in Poultry Intestine

Other trials conducted on a commercial farm in China with 48-week-old laying hens showed that FermNutral improved laying rate (+1.4) and shell thickness (+0.05 mm), while reducing feed conversion ratio (-0.06) and broken eggs (-2.6%), without affecting other productive performance parameters.

Likewise, in an experiment carried out at Henan Agricultural University, China, using 50-week-old laying hens, FermNutral increased egg weight (61.63 vs 59.77 vs g) and improved feed conversion ratio (2.08 vs 2.11 vs), while reducing dirty eggs (0.17 vs 0.45 %), broken eggs (0.32 vs 0.47 %), and unfit eggs (0.15 vs 0.28 %). These results demonstrate that FermNutral is an innovative and differentiated alternative within the new generation of postbiotics.

References
De Marco S, et al. (2018). Probiotic cell-free supernatants exhibit anti-inflammatory and antioxidant activity. Evidence-Based Complementary and Alternative Medicine.
Liu H, et al. (2023). Postbiotics modulate gut health and laying performance in laying hens. Animal Nutrition, 14, 244–256.
Muhammad I, et al. (2021). Lipoteichoic acid from Bacillus subtilis improves immune function of broiler chickens. Antioxidants, 10(9), 1414.
Pasquina LW, et al. (2013). Teichoic acid biosynthesis as an antibiotic target. Current Opinion in Microbiology, 16(5), 531–537.
Zhong R, et al. (2022). Gut microbiota and its interactions with postbiotics in animal production. Frontiers in Microbiology, 13, 831495.
About CPBIO – A Global Biotech Company, Based on the global practice of Charoen Pokphand Group in the agricultural, animal husbandry and food industry chain, CPBIO has extensively and deeply participated in the health cause of animals, the earth and human beings with the thinking of the whole industry chain. Organizations and individuals in large-scale validated products and solutions.

About CPBIO – A Global Biotech Company, Based on the global practice of Charoen Pokphand Group in the agricultural, animal husbandry and food industry chain, CPBIO has extensively and deeply participated in the health cause of animals, the earth and human beings with the thinking of the whole industry chain. Organizations and individuals in large-scale validated products and solutions.

Every day, a broiler’s intestine processes several times its body weight in feed and water, encounters billions of microorganisms, responds to environmental stress, and continuously decides what enters the body and what remains outside.

In many ways, the gut functions as a customs checkpoint, security system, digestive factory, and immune headquarters—all at the same time.

In fact, nearly 70% of the bird’s immune cells are associated with the gastrointestinal tract, making it a key player in both health and performance. The remarkable aspect is that when the gut is functioning well, nobody notices it. When it begins to fail, everybody notices the consequences.

The Modern Poultry Bird: Built for Speed
Today’s broiler is a biological marvel. Through decades of genetic selection, modern birds reach market weight faster and more efficiently than ever before.
However, this achievement comes with a hidden challenge.

The digestive tract has become one of the most critical performance-limiting organs in poultry production. Every gram of feed must be digested, absorbed, and converted into muscle within an increasingly compressed production cycle.

Twenty years ago, a small reduction in nutrient absorption might have gone unnoticed. Today, even minor intestinal inefficiencies can translate into measurable losses in body weight gain, feed conversion ratio, and profitability. Modern birds can no longer afford a lazy gut.

The Gut Is Constantly Making Decisions
Traditionally, we think of the intestine as a nutrient absorption organ.
In reality, the gut is making thousands of biological decisions every second.

– Should nutrients support growth or immunity?
– Should a microorganism be tolerated or eliminated?
– Should energy be invested in production or defense?
– Should the intestinal barrier remain open for absorption or tighten to prevent invasion?

These microscopic decisions ultimately determine flock performance.
In many ways, poultry production is not simply about feeding birds—it is about influencing the decisions being made within the gut.

The Hidden Cost of Inflammation
One of the most important concepts emerging in poultry science is that inflammation carries a nutritional cost.
Whenever the intestine encounters stress from pathogens, mycotoxins, heat, poor litter quality, or microbial imbalance, the immune system becomes activated.
The immune response is essential for survival, but it is expensive.
Energy that could support growth is redirected toward immune activity.
Amino acids that could build muscle are utilized to produce immune proteins and inflammatory mediators.
Vitamins and minerals become involved in tissue repair and antioxidant defense.
The bird continues eating, yet a significant proportion of nutrients may no longer be contributing to production.
This phenomenon is often referred to as the “hidden feed cost” of inflammation.

The Silent Performance Thief
One of the greatest misconceptions in poultry production is that intestinal problems always produce visible symptoms.
– Not necessarily.
– Many flocks show normal feed intake, acceptable mortality, and no obvious disease outbreaks. Yet they consistently fail to achieve target performance.
– A slight reduction in nutrient absorption.
– A minor microbial imbalance.
– A low level of intestinal inflammation.
– A subtle increase in intestinal permeability.
Individually these changes may appear insignificant. Collectively they can result in substantial economic losses. This is why gut health is increasingly viewed not as a disease issue but as a performance issue.

The Microbial Workforce Inside Every Bird
Perhaps the most fascinating discovery in recent years is the realization that birds are never truly alone.
The digestive tract contains trillions of microorganisms collectively known as the gut microbiome.
These microbes help digest feed ingredients, produce beneficial metabolites, support intestinal development, influence immune responses, and compete with harmful bacteria.
Some scientists now describe the microbiome as an additional organ because of its profound influence on bird health.
This raises an interesting question:
Are we feeding the bird, or are we feeding its microbiome?
The answer is both.
The future of poultry nutrition may depend as much on managing microbial populations as on balancing nutrients.

Heat Stress: The Gut’s Greatest Enemy
In many poultry-producing regions, heat stress has become one of the most significant challenges affecting gut health.
High environmental temperatures reduce blood flow to the intestine, increase oxidative stress, and compromise intestinal barrier integrity.
As a result, harmful bacterial toxins can cross the intestinal wall and trigger inflammation.
Often the first casualty of heat stress is not growth—it is gut integrity.
This may explain why heat-stressed flocks frequently show poorer FCR, increased wet litter, reduced nutrient utilization, and greater disease susceptibility.
As global temperatures continue to rise, protecting gut health during periods of heat stress will become increasingly important.

The Gut in the Antibiotic-Free Era
The poultry industry is rapidly transitioning toward antibiotic-free and reduced-antibiotic production systems.
While this shift addresses consumer concerns and regulatory requirements, it has also increased attention on intestinal health.
Without routine antibiotic growth promoters, producers must rely on alternative strategies to maintain gut stability.
Probiotics, prebiotics, β-glucans, mannan oligosaccharides (MOS), organic acids, phytogenic compounds, and postbiotics are increasingly being used to support intestinal resilience and microbial balance.
The focus is shifting from killing pathogens to creating an intestinal environment where beneficial microbes and the host can thrive together.

More Birds or More Protein?
The global poultry industry is not being asked to produce more birds.
It is being asked to produce more protein.
As the world’s population grows and consumers increasingly seek affordable animal protein, poultry production continues to expand. Industry projections estimate the sector will grow at a CAGR of approximately 5–7% over the coming years.

But growth alone is not enough.
Producers are expected to deliver more meat with fewer resources, lower feed costs, and a smaller environmental footprint.
This means that every gram of feed matters more than ever before.
And that brings us back to the gut.
Because the difference between feed consumed and protein produced is ultimately determined by the efficiency of the digestive system.

The Future Begins in the Gut
For decades, poultry production focused on genetics, nutrition, and disease control.
The next frontier may be intestinal resilience.
Future improvements in productivity will likely come from better management of inflammation, enhanced barrier integrity, optimized microbiomes, and improved nutrient efficiency within the gastrointestinal tract.
The question may no longer be:

“How much feed did the bird consume?”

Instead, the more important question may be:
“How much of that feed actually became growth?”
The answer lies within the gut.
Not because it is merely another organ, but because it is the organ that determines how effectively all the others perform.
In an era of narrow margins, rising feed costs, heat stress, and antibiotic-free production, the healthiest gut may ultimately become the most valuable asset in the poultry house.