Seroprevalence of bovine intestinal schistosomosis in different agro- ecological zones of south India using excretory-secretory antigen based ELISA.

Intestinal schistosmosis caused by Schistosoma spindale and S. indicum is an important snail borne trematode infection that adversely affects the production and productivity of bovines in India. The present communication reports the high seroprevalence of infection among dairy cattle and buffaloes, under field conditions, utilizing a sensitive and specific excretory-secretory antigen based ELISA. Comparison of ELISA with copro-PCR, microscopy and post-mortem mesentery examination revealed the diagnostic superiority of ELISA. Seroprevalence of infection was mapped for the first time in India with special emphasis to agro- ecological zones. Anti-schistosome antibodies were detected in 34.96% of dairy cattle and buffaloes in the state with the evidence of significant influence of topography on the prevalence of infection. The study also highlighted the need to trace endemic pockets of infection in the country through efficient ante-mortem surveillance and to initiate anti-schistosome therapy prior to animal transport.

Evaluation of a recombinant LigB protein of Leptospira interrogans serovar Canicola in an enzyme-linked immunosorbent assay for the serodiagnosis of bovine leptospirosis.

A recombinant leptospiral lipoprotein, LigB, was evaluated for use in the diagnosis of bovine leptospirosis by enzyme-linked immunosorbent assay (rLigB IgG ELISA). The standard reference test (Microscopic agglutination test, MAT) of 200 serum samples from cattle suspected of leptospirosis showed that 95 (47.5%) samples had positive agglutination titres, which ranged from 100 to 1600. In rLigB IgG ELISA, 49% of the samples were positive. Sensitivity of IgG ELISA for 95 bovine sera, which had MAT titres of greater than or equal to 100, were 100%. ELISA showed a specificity of 97.1% with 105 bovine sera, which were negative at a 1:50 dilution in MAT for Leptospira interrogans serovars. The results of ELISA and MAT correspond very good. When analytical specificity of IgG ELISA was evaluated using bovine serum samples from animals showing the serum antibodies to other pathogens, no cross-reaction was observed. Thus the recombinant LigB IgG ELISA can be used instead of the MAT as an aid to the diagnosis of bovine leptospirosis.

Identification of PDC-109-like protein(s) in buffalo seminal plasma.

The FN-2 family of seminal plasma proteins represents the major protein fraction of bovine seminal plasma. These proteins also constitute the major seminal plasma proteins fraction in horse, goat and bison seminal plasma and are present in pig, rat, mouse, hamster and human seminal plasma. BSP-A1 and BSP-A2, the predominant proteins of the FN-2 family, are collectively termed as PDC-109. Fn-2 proteins play an important role in fertilization, including sperm capacitation and formation of oviductal sperm reservoirs. Significantly, BSP proteins were also shown to have negative effects in the context of sperm storage. No conclusive evidence for the presence of buffalo seminal plasma protein(s) similar to PDC-109 exists. Studies with buffalo seminal plasma indicated that isolation and identification of PDC-109-like protein(s) from buffalo seminal plasma by conventional methods might be difficult. Thus, antibodies raised against PDC-109 isolated, and purified from cattle seminal plasma, were used for investigating the presence of PDC-109-like protein(s) in buffalo seminal plasma. Buffalo seminal plasma proteins were resolved on SDS-PAGE, blotted to nitro cellulose membranes and probed for the presence of PDC-109-like protein(s) using the PDC-109 antisera raised in rabbits. A distinct immunoreactive band well below the 20-kDa regions indicated the presence of PDC-109-like protein(s) in buffalo seminal plasma.