title: Pathology and diagnosis of Mycobacterium bovis in naturally infected dromedary camels (Camelus dromedarius) in India.
abstract: The present study investigated the pathological features of tuberculosis (TB) caused by Mycobacterium bovis and its diagnosis in naturally infected dromedary camels from an organized farm in India. During the period of the 5-year study, a total of 18 (19.56 %) camels out of 92 examined showed gross lesions compatible with TB at post-mortem. The clinical signs and pathological lesions in these camels were studied, and the efficacy of different diagnostic tests was also assessed. On the basis of occurrence and distribution of gross TB lesions, the infected camels revealed two different lesional patterns as pulmonary (n = 15) and disseminated (n = 3) form. The histopathology of affected organs revealed typical granulomatous lesions wherein the giant cells and acid-fast bacilli were occasionally observed in pulmonary form whereas they frequently observed in disseminated form. The single intradermal tuberculin test (SIDT) detected TB in 10 (55.55 %) whereas the Ziehl-Neelsen (ZN) stain and IS6110 PCR from tissue lesions detected 13 (72.22 %) and 18 (100 %) of the infected camels, respectively. The study suggests that pulmonary form of the TB is more common in camels indicating respiratory route as the major source of exposure in camel herds. Moreover, very low sensitivity of SIDT was observed which highlights the difficulty for confirmation of TB in live camels.
authors: National Research Centre on Camel, Jorbeer, Bikaner, 334001, Rajasthan, India. drshirish009@gmail.com.
authors: Shirish Dadarao
authors: SD
authors: Narnaware
authors: National Research Centre on Camel, Jorbeer, Bikaner, 334001, Rajasthan, India.
authors: Shyam Singh
authors: SS
authors: Dahiya
authors: National Research Centre on Camel, Jorbeer, Bikaner, 334001, Rajasthan, India.
authors: Fateh Chand
authors: FC
authors: Tuteja
authors: Southern Regional Research Centre, Central Sheep and Wool Research Institute, Mannavanur, Kodaikanal, Dindigul, 624103, Tamil Nadu, India.
authors: Govindasamy
authors: G
authors: Nagarajan
authors: National Research Centre on Camel, Jorbeer, Bikaner, 334001, Rajasthan, India.
authors: Kashi
authors: K
authors: Nath
authors: National Research Centre on Camel, Jorbeer, Bikaner, 334001, Rajasthan, India.
authors: Nitin Vasantrao
authors: NV
authors: Patil
mesh_terms: D000818:Animals; D002162:Camelus / Q000382:microbiology*; D002417:Cattle; D005189:False Positive Reactions; D005260:Female; D006099:Granuloma; D007194:India; D007428:Intradermal Tests / Q000662:veterinary*; D008297:Male; D009163:Mycobacterium bovis / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012307:Risk Factors; D014374:Tuberculin Test / Q000662:veterinary*; D014380:Tuberculosis, Bovine / Q000175:diagnosis*
keywords: Camel; IS6110 PCR; Mycobacterium bovis; Pathology; Tuberculosis