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Septicaemic diseases are the leading cause of mortality in piglets causing great economic loss to the porcine industry. Haemophilus parasuis, an important pathogen in piglets, is widely distributed in all pig rearing countries. Carrier pigs are considered as the major reservoir of H. parasuis and could be a significant source of infection leads to septicaemia and pneumonia in pigs. In this study, a total of 51 tissue samples from different outbreaks of septicaemia in and around Bareilly district of Uttar Pradesh state of India were evaluated for H. parasuis infection by PCR and histopathological examination. A total of 12 samples were found positive for H. parasuis on screening (12/51, 23.52%). On post mortem examination, the gross lesion in lungs, heart, spleen and brain indicated establishment of septicaemia and pneumonia. The predominant histological changes observed were fibrinous polyserositis and bronchopneumonia as compared to other tissue lesions such as splenitis, nephritis, myocarditis and meningitis. The involvement of lymph nodes and joints were also observed as an important finding of the H. parasuis infection. The study revealed H. parasuis is prevalent in Indian pigs and is responsible for large outbreaks of septicaemia. In this context, more studies targeting the H. parasuis are highly warranted to establish its pathology and pathogenesis among Indian pigs.

To understand the mechanism of host-pathogen interaction during the progression of Pasteurella multocida capsular serotype D of porcine origin causing pneumonia/septicemia, 36 adult Swiss albino mice were intranasally inoculated with 25 μl of P. multocida serotype D@109 CFU/ml and sacrificed at 6, 12, 24, 48, 72 and 96 hours post inoculation. The infected mice showed varied clinical signs of depression, ruffled fur, ocular discharge, watery to mucoid nasal discharge with labored breathing pronounced during 24-48 HPI and declined thereafter. The leucocytosis, anaemia, low PCV, progressive neutrophilia with lymphocytopenia changes in these infected groups of mice paralleled with the clinical signs. The serum biochemical parameters such as total protein, blood urea nitrogen, creatinine, glucose, SGOT, SGPT and C-reactive protein were significantly increased. The higher level of LPO, lower level of antioxidant enzymes (CAT, SOD and GSH) and higher values of proinflammatory cytokine genes (TNF-α, IL-1β and IL-6) in lungs and spleen of the inoculated mice as compared to control mice suggest towards the establishment of pneumonia and sep-ticemia. The lesions of bronchopneumonia, splenitis, nephritis, hepatitis, enteritis and myocarditis along with the demonstration of bacterial antigens in lungs and spleen well correlated with severity of histopathological lesions at different time points. Apoptotic nuclei were detected in infiltrating leukocytes of the lungs and splenocytes on TUNEL staining. The inflammatory lesions as well as the apoptosis were highest during 24-48 HPI followed by gradual decrease till the end of the experiment. This is the first report on elucidating the pathogenesis of P. multocida capsular serotype D of porcine origin.

Streptococcus suisis an emerging bacterial pathogen causing high mortality in nursery pigs. The prevalence of S. suis in piglets especially in nursery piglets of India is not known and needs to be addressed for its effective control. A total of 243 biological samples (152- nasal swabs; 57-palatine tonsils; 21-dead piglets and 13-joint fluids) were collected from both healthy and diseased preweaned piglets. Out of 209 samples from the asymptomatic piglets processed for microbiological investigations, 14 cultures were isolated (6.69%) while higher positivity was recorded by molecular method (68.4%) showing greater efficacy of molecular method for detection of S. suis infections in piglets. In diseased piglets, 5 isolates were recovered by routine culture method while40 cases (43.47%) were detected by molecular means. Majority of the isolates belonged to serotype 2 (9/19; 47.36%) followed by serotype 5 (5/19; 26.31%), serotype 7 (3/19; 15.78%) and serotype 9 (2/19; 10.52%). The predominant genotype was found to be mrp-/epf-/sly-/arcA- in both the cases. The piglets died of S. suis infections showed pneumonia, hepatitis, nephritis, splenitis, tonsillitis, enteritis with the demonstration of bacterial antigens at the site of lesions confirm its association with the development of the disease. Moreover, mouse pathogenecity testing of S. suis isolates confirm its pathogenic potential irrespective of its genotypes. This is the first report on documenting the prevalence and characterization of S. suis among healthy and diseased preweaned piglets of India.

A 4-week-old male crossbred piglet was presented for necropsy examination with history of neurological signs progressing to death. Grossly, the meninges covering the brain were thickened, opaque containing purulent exudates. Besides, the other visceral organs like lungs, heart, spleen, lymph nodes, kidneys and intestine were severely congested. Histologically, suppurative meningoencephalitis was observed in addition to suppurative bronchopneumonia, hepatitis, nephritis and splenitis indicating the septicemia in pig. Immunolabelling of S. suis antigen was observed in meninges, brain, lungs, spleen, tonsil and lymph nodes. Both S. suis and S. dysgalactiae subspecies equisimilis were isolated from the brain, lungs and spleen. The biochemical characterization by API 20 strep kit and genomic detection test by PCR further confirmed both the isolates. This is the first report of dual infection of S. suis and S. dysgalactiae subspecies equisimilis infection in a pig with severe disseminated suppurative meningoencephalomyelitis.

Pneumonic Pasteurellosis caused by Pastenrella mnltoeida is an economically important veterinary pathogen confronting swine industry worldwide. Despite continuous investigations on its various aspects of pathogenesis, role of apoptosis and its pathway in the development of lesions has not been investigated. Thus, the authors investigated the role of various apoptosis pathways in the pathogenesis of lesions in pigs suffering pneumonic Pasteurellosis. A total of 10 lungs tissues from pigs naturally died of Pasteurellosis were subjected to immunohistochemical investigation for the demonstration of apoptosis and its pathway. Caspase-3 & Annexin-V staining were markedly stronger in the inflammatory cells and the endothelial lining cells of the blood vessels confirming the role of apoptosis. The caspase-8 staining was more pronounced in the inflammatory cells adjacent to necrotic lesions throughout the sections of the lungs whereas mild to moderate immunoreactivity of Cacaspase-9 was noticed only in focal areas of 2 cases. In addition to it, moderate P53 staining was noticed surrounding the necrotic lesions. However, the tissues failed to show any immunolabelling for Apafl and Bcl-2 antibodies. This study clearly illustrates ex vivo that the activation of the P53 mediated caspase dependent extrinsic pathway is a key element in the pathogenesis of pneumonic lesions observed in pigs infected with Pastenrella mnltoeida.

Hepato-renal syndrome is a type of functional kidney failure due to acute or chronic liver diseases. A five year old female, crossbred goat was presented for post-mortem examination. On necropsy, icteric discoloration of carcass with enlarged liver, thickened jejunal and ileal mucosa and enlarged mesenteric lymph nodes were observed. Severe lipidosis of liver, hypertrophied hepatocytes, mononuclear cell infiltration of parenchyma and portal triads, fusion of villi, and extensive infiltration by mononuclear cells (epithelioid-macrophages, plasma cells and lymphocytes) and occasional giant cells were observed around a central caseated and calcified mass surrounded by fibrous tissue proliferation in the lamina propria of intestine. Calcification of the mesenteric lymph node was confirmed by Von Kossa staining as dark brown to black deposits. Severe glomerular and tubular degeneration, necrosis and presence of bile casts were observed in kidney, which was confirmed by Hall's staining. Diffuse golden yellow hemosiderin pigment deposits were observed in the splenic parenchyma, which wasconfirmedbyPerl's Prussianbluestainingasbluishblackpigments. Ziehl-Neelsenstainingrevealedacid-fastbacilli inthelamina propria of intestine. Immunohistochemistry (IHC) using anti-M. aviumsubspp. paratuberculosis immune serum showed positive brown signals intracellularly in the macrophages and epithelioid cells in the lamina propria of intestine. Demonstration of acid-fast organism and IHC confirmed paratuberculosisinfection and the cascade of injury consequent to the disease might have resulted in hepato-renal syndrome and death of the affected animal.

Altogether 185 pig carcasses from privately run slaughter slabs of Rohilkhand region were screened to ascertain the prevalence of cysticercosis. Out of them, 14 cases (7.56%) were found to be infected with cysticercosis. The cysts were found distributed heavily within the skeletal, cardiac and scrotal muscles, and onto the leptomeninges of the brain causing pressure atrophy. Histological examination showed cystic structures within the musculature along with vascular congestion, infiltration of inflammatory cells within the connective tissue. The brains showed cystic cavities with or without the presence of parasites, meningo-encephalitis, perivascular cuffing, neuronophagia and focal gliosis.

A rare case of ‘Diprosopus monauchenos’ was recorded in a newborn live piglet from a five year-old multipara sow. The unique animal had two faces fused caudally by a single parietal bone and joined ventrally by the medial ramie of the mandible. The ‘diprosopus’ consisted of four eyes (tetraophthalmus), two pairs of nostrils, two mouths and each with a tongue. The piglet died on second day besides best nourishing care. Clinical and radiographic observations revealed normal anatomic, thoracic and abdominal viscera and confirmed the aforementioned findings.