XCELSIO wsp
Product Name: XCELSIO wsp
Type: Bacteriophage (Water Soluble Powder)
COMPOSITION
DESCRIPTION
XCELSIO wsp is a water-soluble bacteriophage-based feed additive formulated for convenient administration via drinking water. It contains a live cocktail of lytic bacteriophages that specifically target and eliminate key pathogenic bacteria while preserving beneficial gut microbiota
What Are Bacteriophages? Bacteriophages (or "phages") are viruses that infect and replicate only in bacterial cells. They are ubiquitous in the environment and recognized as the earth's most abundant biological agent, outnumbering bacteria by approximately 10:1
Mechanism of Action: Lytic Replication XCELSIO wsp utilizes exclusively lytic (virulent) bacteriophages, which follow a distinct lifecycle
Adsorption: The phage attaches to specific receptors on the surface of its target bacterial host using specialized tail fibers. This specificity ensures that only pathogenic bacteria are targeted
Injection: The phage injects its genetic material (DNA or RNA) into the bacterial cell cytoplasm
Replication & Assembly: The phage hijacks the host bacterium's cellular machinery to synthesize new phage components. Multiple copies of the phage are assembled within the bacterial cell
Lysis: The host bacterium is lysed (destroyed), releasing hundreds of new phage particles that continue to seek out and destroy additional target bacteria. This self-perpetuating mechanism provides sustained pathogen reduction
This lytic replication cycle is self-limiting—when the target bacterial population is reduced, phage numbers naturally decline as they lose their hosts
Lytic vs. Temperate Phages: XCELSIO wsp utilizes exclusively lytic bacteriophages, which kill their host bacteria upon replication. This is distinct from temperate phages, which can integrate into the bacterial genome (lysogenic cycle) without immediately killing the host
Water-Soluble Powder Formulation: As a water-soluble powder (also known as a soluble powder or "wsp"), this product is designed to dissolve completely in water, allowing for easy and uniform administration via drinking water systems. This formulation is particularly advantageous for poultry and swine operations where drinking water is the primary administration route
Regulatory Milestone: In July 2025, the European Union officially approved the first-ever bacteriophage-based feed additive for poultry under Regulation (EC) No 1831/2003. The EFSA FEEDAP Panel concluded that such bacteriophage additives are safe for target species, consumers, and the environment
EFFICACY DATA
Salmonella Control: A study evaluating bacteriophage cocktail supplementation in broilers infected with Salmonella gallinarum reported that a phage cocktail at concentration 1011 PFU/ml was able to protect 100% of infected birds, with significantly reduced fecal shedding rates (1.2% vs. untreated group) and significant improvement in body weight gain
Another study demonstrated that dietary supplementation of bacteriophages at 1000 g/ton improved body weight gain and feed conversion ratio in both challenged and unchallenged chickens, while increasing beneficial Lactobacillus counts and decreasing pathogenic bacteria
Necrotic Enteritis (Clostridium perfringens) Control: A 2025 study evaluating bacteriophage supplementation in broilers challenged with Clostridium perfringens type G reported: improved feed intake, body weight gain, and feed conversion ratio (p < 0.05); reduced intestinal lesion scores and mortality; restored jejunal histomorphology; and ameliorated blood biochemical disturbances
Summary of Efficacy Data:
| Target Pathogen | Key Findings | Reference | \n\n
|---|---|---|
| Salmonella spp. | 100% protection at 1011 PFU/ml; reduced fecal shedding; improved BWG | Kumar et al., 2023 |
| S. Enteritidis | 1000 g/ton improved BWG and FCR; increased Lactobacillus; reduced oxidative stress | Saleh et al., 2025 |
| C. perfringens | Improved feed intake, BWG, and FCR (p < 0.05); reduced intestinal lesions and mortality | University of Vet & Animal Sciences, 2025 |
| Dual Serotype Salmonella | Dual activity against S. Enteritidis and S. Typhimurium; rapid adsorption; 12h inhibition | Kim et al., 2025 |
INDICATIONS
XCELSIO wsp is indicated for the prevention and control of bacterial infections caused by the following pathogens in livestock and poultry:
Primary Applications:
DOSAGE & ADMINISTRATION
For administration via drinking water. Prepare fresh solution daily. The water-soluble powder dissolves completely in water for uniform distribution.
Recommended Inclusion Rates:
| Species | Recommended Dose | Target Concentration | \n\n
|---|---|---|
| Poultry (Broilers & Layers) | 0.5 – 1.0 g per liter of drinking water | 108 – 1010 PFU/liter |
| Swine | 0.5 – 1.0 g per liter of drinking water | 108 – 1010 PFU/liter |
| Cattle (Calves) | 2 – 5 g per 100 liters of drinking water | 108 – 1010 PFU/liter |
Administration Guidelines:
ADVANTAGES OF WATER SOLUBLE FORMULATION
SAFETY & REGULATORY STATUS
WITHDRAWAL PERIODS
PRECAUTIONS & STORAGE
Target Species: Poultry (Broilers, Layers, Turkeys), Swine, Cattle (Calves)
Pack Sizes: 1 kg, 20 kg
PRODUCT SUMMARY
XCELSIO wsp Bacteriophage Water Soluble Powder Bacteriophages targeting: Salmonella spp., E. coli, Staphylococcus aureus, Clostridium perfringens, Bacillus subtilis Livestock 1 Kg,20Kg
FOR VETERINARY USE ONLY