Isolation of Eimeria spp. from Chicken Feces
Isolating Eimeria species from chicken feces is crucial for
diagnosing and studying coccidiosis, a significant disease in poultry.
The following procedure outlines the steps to recover Eimeria oocysts
for analysis.
1. Collection and Homogenization
- Collect fresh fecal samples using sterile
containers to avoid contamination.
- Homogenize feces in saline solution (0.85% NaCl) or
distilled water to form a slurry, releasing oocysts from the fecal
matter.
2. Concentration
- Flotation Technique:
- Use a flotation solution (specific gravity around 1.2) like
saturated salt, sucrose solution, or Sheather’s sugar solution.
- Mix fecal slurry with the flotation solution and pour into a
flotation device.
- Centrifuge at low speed (1,500 rpm) for 5-10
minutes. Oocysts will float to the surface.
- Collect the surface layer (flotation layer)
containing oocysts with a loop or pipette.
3. Purification
- Washing: Wash the oocyst suspension several times
with distilled water by centrifugation to remove the flotation
solution.
- Filtration: Filter the suspension through a fine
mesh to remove debris, retaining oocysts.
4. Identification and Quantification
- Microscopic Examination: Identify Eimeria oocysts
under a microscope by size, shape, and internal structures.
- Counting: Use a hemocytometer or McMaster counting
chamber to estimate oocyst concentration.
5. Storage
- Store oocysts in 2.5% potassium dichromate solution at 4°C if not
analyzed immediately.
6. Safety and Precautions
- Follow biosafety level 1 practices, wearing gloves and lab coats to
prevent contamination and ensure safety.
7. Further Analysis
- For species identification or genetic studies, employ molecular
techniques like PCR, requiring DNA extraction from the oocysts.
This guideline provides a general approach for isolating Eimeria
oocysts from chicken feces. Modifications may be necessary based on
study objectives, sample conditions, or specific Eimeria species.