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for confirmation of PPRV infection as the primary cause of this disease outbreak. Vaccination is commonly followed worldwide to prevent both the disease but still occurs in unvaccinated flocks and following vaccine failure.
Table 1 Breed and sex, age wise categorization of goats in the affected population India is an agrarian nation with a considerable population having agriculture as their occupation, where livestock plays an important role. But for marginal or landless labourers and pastoral farmers sheep and goats play a pivotal role for their socio-economic upliftment. The total Goat Population in the country is 135.17 million numbers in 2012. The sheep and goat population in Tamil Nadu is 172.66 lakhs (All India Report, 2012). The greatest concern to sheep and goat industry is the prevalence of deadly infections, their prevention and management strategies practiced. Worldwide important infectious diseases of sheep and goats are Blue tongue, Pox, Peste des petits ruminants (PPR), Lenti virus and enterotoxaemia. PPR is a devastating infectious disease caused by the PPR virus, a member of the morbillivirus genus of the family Paramyxoviridae. PPR (peste des petits ruminants) is a most important viral disease of goat capable of heavy mortality and commonly called as goat plague. The PPRV genome consists of a single stranded negative sense RNA of approximately 16 kilobases containing six genes, encoding 6 structural and 2 non structural proteins. The virus exists as a single serotype. In India the disease was first reported in Arasur village in Villapuram district, Tamil Nadu (Shaila et al., 1996). The economic losses due to PPR in goats and sheep is Rs 8895.12 crores, of which Rs. 5477.48 crores loss due to PPR in in goats while Rs. 3417.64 crores loss due to PPR in sheep (Singh et al., 2014). Clostridium perfringens is a ubiquitous entero-pathogen (Ferrarezi et al., 2008) commonly seen in well fed animals (Jemal et al., 2016). The morbidity rate does not exceed 10% of the herd strength, but its lethality usually kills 100% of the affected animals. C. perfringens is prevalent throughout the world and possess different toxins in the arsenal to cause disease in different species of animals. Clostridium spp. are gram positive, non-motile, rod shaped, anaerobic bacteria distributed in the soil and digestive tract of animals (Sawires & Songer, 2006; Uzal et al., 2014). The C. perfringens is a heterogenous group of organism with respect to their metabolic by- products, toxins and pathogenic potential and is divided into five types from A to E based on lethal toxins (alpha, beta, epsilon and iota) (Smedley & McClane, 2004). Types B, C and D are commonly associated with disease in domestic animals and are one of the most important causes of sudden death in goats of different ages. However, no single strain produces this entire toxin panoply. C. perfringes type C and D are normal commensals of the gut micro-flora of healthy sheep and goats and thus poses the risk of infected animals entering the food chain (Wojdat et al., 2006) and producing histo-toxic and enteric diseases in both humans and other animals. A primary PPR viral infection causes remarkable immune-suppression that leads to secondary infections with high morbidity and mortality. The study was undertaken to know about the clinico-pathological findings in goats during a natural outbreak of concurrent viral and bacterial infection and detection of the viral genome in tissues by PCR and the bacterial toxin by biological assay. 2 MATERIALS AND METHODS: 2.1 Flock Investigation The flock had at the time of first death, a total of 520 goats (80% Tellichery & 20% Kanni breed). There was no proper vaccination history for the animals. The flock was managed in semi intensive system and animals were housed in sheds having slatted flooring and fed with concentrates and roughages. Table 1 shows the animal population in the affected farm 2.2 History and clinical signs In a herd of 520 heads, kids between the age group of 3-6 months suddenly started to die and within a short span of one month 40 kids had died in January- February of 2015. Females were affected more than the males. Some animals showed diarrhoea, muco-purulent bilateral nasal discharge, recumbency, opisthotonous, convulsion and internal vocalizing. Pregnant animals aged between 1 to 2.5 years were reported to have still
S. No Tellichery breed % Kanni breed % 1 Bucks 36 10.81 Bucks 12 11.54 2 Does 297 89.19 Does 72 69.23 3 Kids 83 20 Kids 20 20 4 Total 416 80 Total 104 20
Table 2 Details of the disease outbreak pattern in the farm
S. No Time period Kids died Mortality rate- % Age group (months) Adults T/K Symptoms 1. 3rd week of January 6 15% 3-3 1/2 - Anorexia, High Fever, Diarhoea, Nasal discharge 2. 4th week of January 9 22.5% 5-5 1/2 K-mild nasal discharge Anorexia Diarrhoea, Sore mouth, Weight loss, Nasal & ocular discharge 3. 1st week of February 5 12.5% 7 - Mucopurulent bilateral nasal and ocular discharge, ulcers, debility 4. 2nd week of February 6 15% 4 T-Still births(5) Recumbency, Opisthotonous, Internal Vocalization. 5. 3rd week of February 7 17.5% 4 & 6 T-Abortions (2) 6. 4th week of February 7 17.5% 5 & 7 T-2 died Nervous signs, sudden death