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.     

Isolation and characterization of an Indian ORF virus from goats

Isolation and characterization of an orf virus has been described here. The virus was isolated from an outbreak of 'scabby mouth' in goats in Northern India. Viral morphology from the scab biopsy revealed typical ovoid-shaped particles characteristic of Parapoxvirus. Virus was isolated from sonicated scab suspension and characterized by restriction enzyme (RE) analysis and sequencing of full-length GM-CSF- and interleukin-2 inhibitory factor (GIF) gene. RE pattern of the virus did not show close resemblance to most of the orf viruses published earlier. However, it showed high sequence identity and closer phylogenetic relationship with previously published ORFV-SA00 strain, as evident from the nucleotide and deduced amino acid sequence of GIF gene.     

The current status of sheep pox disease

Sheep are the moving banks of shepherds and their economic contribution in terms of meat, wool and skin/hide is immense. Various infectious diseases jeopardize the optimum productivity; among which sheep pox is more important as the disease restricts the export of sheep and their products besides other economic losses. Although, clinical signs are indicative of the disease but a laboratory confirmation is necessary for unequivocal diagnosis and studying epidemiology. The causative agent, sheep pox virus (SPV), is antigenically and genetically closely related to goat pox virus (GPV) and lumpy skin disease virus (LSDV), the other members of the genus capripox virus. In some countries, SPV and GPV are cross infective to small ruminants posing problem in diagnosis and epidemiology. However, recent studies have showed that the viruses are phylogenetically distinct and can be differentiated by molecular tools. Prophylaxis using attenuated vaccines is the choice of control measure as the immunity is long lasting. Detailed information on isolation, identification, pathology, epidemiology, diagnosis and prophylaxis would not only help in updating the knowledge of scientific fraternity but will be useful to the policy makers in order to formulate appropriate measures for control and eradication of the disease. This synthesis is to present an up-to-date review of the disease and its control to provide the reader with an overview of the problem.     

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.     

A Classical Live Attenuated Vaccine for Sheep Pox

A classical live attenuated sheep pox vaccine was prepared using the Ranipet strain of sheep pox virus (SPV) at the 50th passage in a secondary lamb testicular cell system. The TCID50 and RD50 were 10(9.63)/ml and 10(9.51)/ml. respectively. The SID50 of SPV challenge virus was 10(5)/ml. The vaccine was found to have no adverse effects in laboratory animals, and was safe and effective in SPV seronegative lambs. In the field, 660 sheep were vaccinated with an immunizing dose containing 1 x 10(2) TCID50. Randomly selected vaccinated sheep mounted good cell-mediated immunity and humoral responses as measured by glucose utilization test and serum neutralization test, respectively, for the study period of 6 months.     

Assessment of nebulisation of sodium ceftiofur in the treatment of calves naturally infected with bovine respiratory disease

Twelve screened cases of bovine respiratory disease (BRD) in calves were enrolled. Six of the calves were treated intramuscularly with sodium ceftiofur (1 mg/kg), and six were treated with nebulised sodium ceftiofur (1 mg/kg). Comparative evaluation of the two therapeutic modalities was based on repetitive analysis of hematological profile of calves on days 0, 5, and 10 post-therapy. The mortality rate in the group of calves treated with the nebulised sodium ceftiofur was significantly (p?<?0.001) lower, and their clinical and hematological parameters returned to normal significantly (p?<?0.001) faster than in calves treated intramuscularly. Nebulisation of sodium ceftiofur is the most effective treatment in calves with BRD under field conditions. Nasal lavage fluid analysis indicating a high rise of neutrophil count and macrophages may be used as an alternative method to detect pulmonary inflammation in BRD-affected calves.     

Comparative sequence analysis of major envelope protein gene (B2L) of Indian orf viruses isolated from sheep and goats

Orf virus (ORFV), the type species of Parapoxvirus, is responsible for contagious ecthyma in sheep and goats. In the present report, sequence analysis of major envelope gene (B2L) of four Indian orf virus isolates originating two each from sheep and goats was carried out. These recent isolates belonged to different outbreaks that occurred in Kumaon hills and adjoining plains during 2004-2005. Preliminary screening of the scab samples was carried out by diagnostic PCR. Full-length B2L gene encoding for immunogenic major envelope protein from all the four ORFV isolates was amplified by PCR and the amplicons (1206 bp) were cloned and sequenced. Comparative sequence analysis revealed an open reading frame of 1137 nucleotides (nt) encoding a polypeptide of 378 amino acids (aa). Indian isolates were highly related amongst themselves with sequence identity of over 97% at the nt and aa level. Further, they showed 97-98% sequence identity with sequences of other ORFV isolates from around the world; while 94-95 and 82.7-83.8% sequence identity was observed, respectively, with pseudocowpox and bovine papular stomatitis viruses--the other members of the genus. Phylogenetic analysis also showed that these Parapoxviruses from sheep and goats are closely related to other orf viruses reported worldwide.     

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.