Prevalence of Leptospira serogroup-specific antibodies in cattle associated with reproductive problems in endemic states of India

Tropical Animal Health and Production - In this study, the seroprevalence and distribution of Leptospira in dairy cattle in endemic states of India were investigated in association with...     

Seroprevalence of Peste des petits ruminants in cattle and buffaloes from Southern Peninsular India

This study describes seroprevalence of Peste des petits ruminants (PPR) in cattle and buffaloes carried out during the period 2009–2010 using the randomly collected serum samples from different parts of Southern peninsular India. The report presents the results of PPR virus (PPRV)—specific antibodies in situations where either the subclinical or inapparent or non-lethal infection was there in cattle and buffaloes. A total of 2,548 serum samples [cattle = 1,158, buffaloes = 1,001, sheep = 303 and goat = 86] were collected and screened for PPRV antibodies by using a PPR monoclonal antibody-based competitive ELISA kit. Analysis of 2,159 serum samples indicates an overall 4.58% prevalence of PPRV antibody in cattle and buffaloes. The presence of PPRV-specific antibodies demonstrates that cattle and buffaloes are exposed to PPR infection naturally, and the transmission mode may be direct or indirect. Further, it implies the importance of bovines as subclinical hosts for the virus besides widespread presence of the disease in sheep and goats in the country.     

Prevalence of peste des petits ruminants among sheep and goats in India

This study measured the clinical prevalence of peste des petits ruminants (PPR) among sheep and goats in India between 2003 and 2009 by analyzing clinical samples from suspected cases of PPR that were submitted to the Rinderpest and Allied Disease Laboratory, Division of Virology, IVRI, Mukteswar for PPR diagnosis. PPR outbreaks were confirmed by detecting PPR virus (PPRV)-specific antigen in the clinical samples. Clinical samples (blood, nasal swabs, spleen, lymph node, kidney, liver, intestine, and pooled tissue materials) were taken from a total of 592 sheep and 912 goats in different states of India and screened for the presence of PPRV antigen using a monoclonal antibody-based sandwich ELISA kit. A total of 20, 38, and 11 laboratory-confirmed PPR outbreaks occurred among sheep, goat, and combined sheep and goat populations, respectively. Our findings provide evidence of widespread PPR endemicity in India. The underlying reasons could be variations in husbandry practices in different geographical regions, agro-climatic conditions, and livestock migration. Furthermore, decrease in the number of PPR outbreaks over time might be due to the effectiveness of current live PPR vaccines and timely vaccination of target species. Vaccination against PPR has been practiced in India since 2002 to control this disease.     

Peste des petits ruminants virus detected in tissues from an Asiatic lion (Panthera leo persica) belongs to Asian lineage IV

In this study, peste des petits ruminants virus (PPRV) was detected in frozen pooled tissue samples from a dead Asiatic lion (Panthera leo persica). The samples were negative for canine distemper virus and positive for PPRV nucleic acids when tested with one-step RT-PCR using the appropriate virus-specific primers. Subsequent amplification, cloning, and sequencing of the partial nucleocapsid, matrix, and fusion genes confirmed the presence of PPRV nucleic acid. Comparative sequence and phylogenetic analyses of the structural genes of the isolated virus confirmed that the virus belonged to Asian lineage IV and was closely related to PPRV circulating in India.     

Comparative sequence analysis of poxvirus A32 gene encoded ATPase protein and carboxyl terminal heterogeneity of Indian orf viruses

Thirteen orf virus (ORFV) isolates from natural outbreaks in sheep and goats belonging to different geographical regions of India were analysed on the basis of ORF108 (a homologue of poxviral A32 gene), which is known to encode for ATPase and involved in virion DNA packaging. Comparative sequence analysis of ATPase proteins revealed highly conserved N-terminal region with five different motifs [Walker A, Walker B, A32L specific motifs (III and IV) and a novel AYDG (motif-V)] among all poxviruses and divergent carboxyl terminus with either single or double RGD sequences among all Indian ORFV isolates. A homology model and secondary structure predictions of N-terminal region of ORFV A32 revealed that most of the poxviruses including ORFV ATPase protein belong to a distinct clade of the HerA/FtsK super family of DNA packaging proteins. Despite differences in host cell specificity and poxvirus infections among animals, DNA packaging motor domain of poxviruses presumed to share remarkable similarities as indicated by the presence of conserved ATPase motifs in the present investigation. The study also indicated the circulation of heterogeneous strains of ORFV in India and possibilities of differentiation of ORFV strains based on C-terminal heterogeneity.     

Molecular typing of Brucella species isolates from livestock and human

Although host specificity has been observed in different species of Brucella, crossing the animal host boundary is likely to occur at any time. In this study, Bruce ladder PCR and abortus–melitensis–ovis–suis (AMOS) PCR assays were used to characterize 47 Brucella isolates from Indian origin in order to know exact species for understanding epidemiology of brucellosis. Out of them, 28, 14, and 5 isolates were found to be Brucella abortus, Brucella melitensis, and Brucella suis, respectively. Further analysis by AMOS PCR has identified that all the B. abortus isolates belong to any one of the biovar 1, 2, or 4; of the five B. suis isolates, three belong to biovar 1 and two belong to any one of the biovar 2, 3, 4, or 5. Although this multiplex Bruce ladder PCR is useful in differentiating all Brucella species, elaborate study is required to further characterize the isolates at exact biovar level.