Journal of Animal and Plant Sciences
J. Anim. Plant Sci. [ISSN 2071 - 7024]
Volume 14(3): 1978 -1984. Published July 30, 2012.
Comparative sensitivity of different phenotypes of free-ranges chicks to Eimeria tenella coccidiosis in Benin
Hervé B. Dakpogan , Sahidou Salifou, Naciri Muriel, Armand Gbangbotche
aApplied Biology Research Laboratory of Polytechnic School of Abomey-Calavi P.O.BOX 2009 Cotonou, UAC, Benin
cDepartment of Animal Production, Faculty of Agronomic Sciences, UAC, Benin
cINRA – UR 86 Bio-Agresseurs Santé et Environnement, 37380 Nouzilly – France
*Author present address Bp 139 Ab Calavi or P.O.BOX 2009 Cotonou Benin, Tel: (00229) 94 62 58 36. E-mail address: dakpogan2002@yahoo.fr
Keywords: Naked neck, dwarf, frizzled, silky, normal feathered
SUMMARY
Sensitivity to was tested on 200 free-range 21 day--old chicks of 5 phenotypes, phenotype naked neck, dwarf, normal, frizzled and silky in a factorial design . Two chicks (male and female) per cage in ten replications were used in each phenotypic group. In total 20 chicks infected and other 20 uninfected controls in each phenotype were used. All the experimental chicks have statistically the same body weight (P > 0.05) and were experimentally challenged with 6 x 104 Eimeria tenella doses. There was similar body weight gain and significant difference (P < 0.05) in disease traits between phenotypes of chicks. Naked neck was the most tolerant phenotype and had the lowest lesion score (1±0.5), lowest proportion of bloody feces (0% at the 6th day post infection), the highest survivability (100%), the fewest Oocysts Per Gram (OPG) (733) and the lowest reduction in packed cell volume (1.5%). The most sensitive phenotype was the dwarf with significantly higher values of lesion score (2.5±0.4), mortality (40%), OPG (604400) and reduction of packed cell volume (12.5%). The other 3 phenotypes of chicks: normal feathered, silky and frizzle had similar (P > 0.05) sensitivity to the infection in terms of lesion score, survivability, bloody feces and oocyst excretion. The significant sensitivity variability observed in this preliminary study, suggests a great disease tolerance potentiality in free-range chicken population that can be valuably exploited in selection programs. Further studies are required to understand the real mechanism underneath the herein established Eimeria tenella coccidiosis divergent expression among free-range chickens’ phenotype.
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