Lesion Scoring of coccidiosis in Poultry

Coccidiosis in chicken

Coccidiosis | Lesion Scoring in Poultry

Lesion Scoring in Poultry

Coccidiosis is the parasitic disease which caused by single cell protozoa of Emeria under the family of Apicomplexa, There are eleven spp of Emeria spp but consider seven species now a days,  producing lesion at various sites in the intestine of poultry.

There are some lesion scoring system applying for diagnosed  coccidiosis both in the laboratory & field. There are reportable three scoring system follows worldwide. Lesion scoring done by following way;

Sites Of Lesion:

Its most important scoring systems where practitioner easily scores by naked eyes. So it’s also called field scoring system. Its broadly divided four section  in the intestine of  poultry.

Sites of lesion scoringTypes of Emeria species present
The Duodenum ( Upper)Emeria acervulina & E. mivati
The Midgut from the duodenum past the mekel’s diverticulumEmeria maxima, preacox, nicartrix, mitis
The lower small intestine from the
mekel’s diverticulum to cecal junction
Emeria maxima, preacox , mitis & brunetti
The CecumEmeria tenella

Anothers techinque follow in control experiment may practice worldwide.This technique explain by Jehnson & Raid using scale 0 to 4, where 0 is normal & 4 is maximum lesion. Emeria maxima is the only Emeria spp they have causing cocidiodiosis early to older birds. This scoring system possible in control experiments where Emeria spp known that’s have separated scale below

Score numberNumber of Emeria parasites present per fields
00No parasites present
011-10 parasites/field
0211-20 parasites/field
0321-49 parasites/field
0450 or above parasites/field

In others coccidiosis eg Emeria nicartrix, brunette,tanella etc  following scoring lesion system:

Score number Number of Emeria parasites present per fields
11-25 parasites/field
2 26-50 parasites/field
3 51-75parasites/field
4 Greater than parasites/field

Microscopic scoring system:

 Lesion scoring also done by Microcsopic examination in coccidiosis. We can see various stages like macro & microgametes, schizont under the microscope caused by Emeria spp For this purpose a small amount of mucosal scraping should be diluted with saline water on a slide and then covered with a coverslip of the sample. Oocysts or macrogametes are most easily seen, but in many cases, the lesion is caused by maturing schizonts of Emeria spp.

Characteristics lesionTypes of Emeria Speciespresent
The clusters of large schizonts
Emeria nicartrix & tenella
The small round oocysts Emeria mitis
The large gemetocysts Emeria maxima
The clusters of large schizonts in the duodenum Emeria acervulina
The clusters of large schizonts in the midgut Emeria nicartrix
The clusters of large schizonts in the cecum Emeria tenella
The clusters of large schizonts in the colonEmeria brunetti

Similar lesion associated with oocyst in the intestine scoring same way. Measurement of 20–30 oocysts of the predominant type of oocyst usually gives a good indication of the size of  the unknown species.

Dropping Scoring:

This types scoring has obvious complication where birds are infected more than one spp. It’s based on extent of abnormal dropping scaled in 4 to 0 where 0 is indicated no diarrhea & 4 indicates maximum diarrhoea.

Scoring numberTypes of Droppings
0No diarrhoea
1Scanty diarrhoea
2Fluidly diarrhoea
3Mucus diarrhoea
4Fluid, mucus, blood with diarrhoea

Writer: Dr Md Ramzan Ali, Poultry Consultant, contact: poultrymania19@gmail.com

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