Effect of tyrode albumin lactate pyruvate and modified Krebs Ringers broth media on in vitro capacitation of HD-K75 boar spermatozoa at different period of incubation.

In vitro capacitation allows for a greater understanding of the mechanisms underlying fertilization and the development of improved reproductive techniques for improving fertility rates in porcine. Tyrodes albumin lactate pyruvate (TALP) and modified Krebs Ringers Broth (m-KRB) are two medias that are commonly used in research experiments to induce capacitation in boar spermatozoa (Cañón-Beltrán et al., Theriogenology, 198, 2023 and 231; Oberlender et al., Archivos de Medicina Veterinaria, 44, 2012 and 201; Sahoo et al., International Journal of Biological Macromolecules, 241, 2023 and 124502). Moreover, understanding the morphological and functional changes in boar spermatozoa at different hours of capacitation periods might aid in the development of novel techniques for improving sperm quality and increasing the litter size. This study was carried out to investigate the effect of Tyrode albumin lactate pyruvate and modified Krebs Ringers Broth media on in vitro capacitation of HD-K75 boar spermatozoa at three different periods of incubation. A total of 24 ejaculate from four clinically healthy, 10-12 months aged HD-K75 boars, maintained at ICAR-All India Coordinated Research Project (AICRP) on pig were selected. Semen was collected by 'Simple fist' method using a portable dummy. The semen samples having 200 mL volume, 103 × 106 spermatozoa/ml concentration and 70% initial motility were selected and split into two parts and suspended in TALP and m-KRB media, respectively, and incubated for 5 h at 37°C. Seminal parameters viz. sperm viability, plasma membrane integrity and acrosomal integrity were estimated in the samples at 0, 3 and 5 h of incubation. This study revealed that there was significant variation between media in live acrosome-reacted (p < .05) and HOST-reacted (p < .01) spermatozoa, while between capacitation periods significant (p < .01) variation was observed in hyperactivated spermatozoa, live acrosome-reacted spermatozoa, HOST-reacted spermatozoa, FITC-labelled PSA, extracellular protein and sperm cholesterol. Non-significant variation was observed in total phospholipid. TALP showed overall better consequence on sperm viability, plasma membrane and acrosomal integrity of boar spermatozoa. From this study, it could be concluded that both TALP and m-KRB media were virtuous to induce capacitation in HD-K75 boar spermatozoa. TALP media, however, had a better effect on sperm viability, plasma membrane and acrosomal integrity of boar spermatozoa. Out of the three different periods, 3 h capacitation period resulted in significantly (p < .01) higher incidence of sperm viability, plasma membrane and acrosomal integrity in HD-K75 boar spermatozoa.

Sero-epidemiology of porcine parvovirus, circovirus, and classical swine fever virus infections in India.

Reproductive problems in swine caused by porcine viruses pose a serious threat to the pig industry in developing countries like India. For evaluating the true extent of porcine infections, a total of 1308 representative sera samples were collected from 92 different pig farms covering 8 North-Eastern states and Punjab state of Northern India during a period of 2 years (2011-2013). Sera samples were tested for the presence of antibodies against porcine parvovirus (PPV), porcine circovirus-2 (PCV-2), and classical swine fever virus (CSFV) using commercial enzyme-linked immunosorbent assay (ELISA) kits. In the North-Eastern states, the seroprevalence of CSFV in non-vaccinated animals was 6.30% and that of PCV2 and PPV was 6.28% and 1.24%, respectively. In Punjab, the seroprevalence of CSFV in non-vaccinated animals was 44.44% and seroprevalence of PCV-2 and PPV was 34.07% and 39.10%, respectively. Detection of antibodies against more than one virus revealed that 4.66% animals had co-infection with PCV-2 and PPV, 1.75% with CSF and PPV, 1.98% with CSF and PCV-2, and 1.75% with all the three viruses. The receiver operator characteristics (ROC) curve analysis depicted that piglet mortality, parvovirus, and CSFV were the most important parameters with an AUC value of 0.997, 0.897, and 0.973, respectively. Incidence of single or co-infection with different viruses showed that the occurrence of single infection was significantly more prevalent than co-infection. This study provides useful information to set up future epidemiologic, flock management, and public animal health policies for the prevention and control of PCV-2, PPV, and CSF in India.

Molecular characterization of classical swine fever virus isolates from India during 2012-14.

Classical swine fever is a highly contagious and economically important viral disease of pigs. Outbreaks of classical swine fever virus (CSFV) were recorded in different places in the Kamrup district of Assam in India between the years 2012 and 2014. The nucleotide sequences of the 10 CSFV isolates were analyzed based on the partial nucleotide sequences of the E2, 5'NTR and NS5B genes. Phylogenetic analysis indicated the dominance of subgroup 2.2 along with 2.1 strains in the northeast part of India. Variation in the nucleotide sequences of E2, 5'NTR and 3'NS5B genes of CSFV allows tracking changes in the virus population over time. The study will provide epidemiological information useful for assessing CSFV circulating genogroups in India.

Molecular characterization of E2 glycoprotein of classical swine fever virus: adaptation and propagation in porcine kidney cells.

Classical swine fever virus (CSFV) is the causative agent of a highly contagious disease, hog cholera in pigs. The disease is endemic in many parts of the world, and vaccination is the only way to protect the animals from CSFV infection. The lapinized vaccine strains are occasionally not protective because of animal to animal passage, inadequate vaccination strategy, suboptimal vaccine dose, and emergence of new variants. The surface glycoprotein E2 of CSFV is a major antigenic determinant and can modulate the disease outcome in pigs. In the present study, we characterized the CSFV in porcine kidney cells. The CSFV vaccine strains showed enhanced replication following 15 passages in porcine kidney cells. Nucleotide sequence analysis of the E2 protein gene of the cell culture-adapted vaccine strain of CSFV showed a mutation in putative amino acid sequences that are identical to its virulent counterpart. The study suggests the possibility of exaltation in vaccine strains following its adaptation in host cells and paves the way for a further exploration of the biology of its outbreak.