Monitoring for Success - Lesion Scoring

Based on severity, the lesion scoring process allows the veterinarian to assess whether a prevention program is working and whether the disease is prevalent in the flock.

Random flock health checks can be completed to assess gut health and performance of the coccidiosis prevention method.

A veterinarian will complete a post-mortem analysis on a random selection of birds. To complete an intestinal lesion score the veterinarian will remove the intestines of the bird and assess the intestinal lesions based on a pre-defined guideline. The veterinarian will assess upper, middle, lower, ceca and rectal sections of the intestine. If needed, the veterinarian can also take microscope slide scrapings of that section of the intestine to confirm the presence of Eimeria life cycle stages.

normalintestine

Figure 1. Normal poultry intestine with important sections and markers labelled that are used when a veterinarian is assessing coccidial intestinal lesions (1, 2).

The guideline for chickens:

Reid, W.M., and P.L. Long. A diagnostic chart for nine species of fowl coccidia. College of Agriculture Experiment Stations, University of Geogia. 1979.

AND

Johnson, J., and W. Reid. Anticoccidial drugs: Lesion scoring techniques in battery and floor-pen experiments with chickens. Experimental Parasitology 28:30-36. 1970.

chickencoccidiaandlesions

Figure 2. Five chicken Eimeria species commonly associated with disease. Eimeria oocysts, location of infection along the intestine and lesions per species are shown (1, 3).

Lesion scores can be completed for turkeys, however a standardized system has yet to be established (4).  General information on coccidiosis lesions of turkeys: 

Reid, M.W., P.L. Long, and L.R. McDougald. Coccidiosis. In: Diseases of Poultry, 8 ed. M.S. Hofstad, B.W. Calnek, M.W. Reid and H.W. Yoder Jr., eds. Iowa State University Press, Ames, Iowa, USA. pp 692-717. 1984.

AND

Chapman, H.D. Coccidiosis in the turkey. Avian pathology 37:205-223. 2008.


turkeycoccidiaandlesionpictures

Figure 3. Five turkey Eimeria species commonly associated with disease. Eimeria oocysts, location of infection along the intestine and lesions per species are shown (3,5,6).

References

1. Reid, W.M., and P.L. Long. A diagnostic chart for nine species of fowl coccidia. College of Agriculture Experiment Stations, University of Geogia. 1979.

2. http://www.animalhealth.bayer.com/4959.0.html

3. Thank you to Dr. Jean-Michel Reperant for chicken Eimeria oocyst photos and E. meleagrimitis lesion photo

4. Holdsworth, P.A., D.P. Conway, M.E. McKenzie, A.D. Dayton, H.D. Chapman, G.F. Mathis, J.T. Skinner, H.C. Mundt, and R.B. Williams. World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines for evaluating the efficacy of anticoccidial drugs in chickens and turkeys. Veterinary Parasitology 121:189-212. 2004.

5. Reid, M.W., P.L. Long, and L.R. McDougald. Coccidiosis. In: Diseases of Poultry, 8 ed. M.S. Hofstad, B.W. Calnek, M.W. Reid and H.W. Yoder Jr., eds. Iowa State University Press, Ames, Iowa, USA. pp 692-717. 1984.

6. Thank you to Ms. Shiem El-Sherry for the turkey Eimeria oocyst photos and E. adenoeides, E. gallopavonis and E. meleagridis photos