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Khan M.H.,ICAR Research Complex for NEH Region | Nath K.C.,ICAR Research Complex for NEH Region | Deka B.C.,ICAR Research Complex for NEH Region | Naskar S.,ICAR Research Complex for NEH Region | And 4 more authors.
Indian Journal of Animal Sciences | Year: 2012

The comparative efficacy of extenders, viz. LEYG (lactose egg yolk glycerol), BTSLEYG (Beltsvilli thawing solution lactose egg yolk glycerol), KEYG (Kiev egg yolk glycerol) and BTSEYG (Beltsvilli thawing solution egg yolk glycerol) were evaluated for cryopreservation of boar semen. Sperm rich fraction of ejaculates (12 each from 3 Hampshire and 3 crossbred boars) were collected by gloved-hand method using dummy sow. Ejaculates having more than 75% initial motility were taken for the study. Each ejaculate was divided in to 4 aliquots and processed with 4 different extenders using 3 h holding time and 1 h equilibration period and frozen in liquid nitrogen using 0.5 ml french medium straws. Each sample was evaluated just after collection and 24 h post-thawing for initial motility, live sperm count, acrosomal integrity and HOST reacted spermatozoa. Results revealed that out of 4 extenders, BTSLEYG was superior than LEYG, KEYG and BTSEYG in respect of post-thawing sperm motility (51.38±0.87 vs 46.79±1.15, 32.50±0.92, 42.71±0.89%), live sperm count (56.83±0.74 vs 55.37±0.96, 45.75±1.34, 54.83±0.81%), acrosomal integrity (56.83±0.74 vs 55.08±0.96, 43.37±0.70, 54.83±0.81%) and hypo-osmotic-reacted spermatozoa (43.79±0.83 vs 39.00±0.91, 36.37±1.01, 36.41±0.71%) respectively. Therefore, it may be concluded that BTSLEYG can be successfully used for cryopreservation of boar spermatozoa using 3% glycerol concentration with 3 hours holding and 1 h equilibration period.

Khan M.H.,National Research Center on Mithun | Nath K.C.,National Research Center on Mithun | Nath K.C.,Assam Agricultural University | Naskar S.,National Research Center on Mithun | And 4 more authors.
Indian Journal of Animal Sciences | Year: 2015

The aim of the present study was to characterize the ultrastructural changes in boar spermatozoa at different stages during freezing (fresh undiluted semen, after holding at 24°C, after cooling to 5°C and after equilibration at 5°C) and after thawing using transmission electon microscopy (TEM). The study was also aimed to compare the sperm characteristics observed through conventional staining procedure with that of electron microscopy. A total of 72 ejaculates were collected from 6 Hampshire boars. Pooled semen was extended in BTSLEYG (Beltsvelli thawing solution lactose egg yok glycerol) extender and frozen in 0.5 ml French straws with conventional vapor freezing technique. Results of routine semen evaluation using conventional staining procedures seemed to be excellent. Microscopically assessed post-thaw percentage of progressively motile spermatozoa, live sperm count, spermatozoa with intact acrosome and hypo-osmotic reacted spermatozoa after thawing were 51.38±0.87, 56.83±0.74, 56.83±0.74 and 43.79±0.83, respectively. TEM examination of frozen-thawed semen revealed major changes in the morphology of spermatozoa localized predominantly within the acrosome and post acrosomal region of a head. Acrosomal and membrane integrity as observed through conventional statining and TEM was found to be 59.83±0.74 vs 37.88±8.85 and 43.79±0.83 vs 31.42±6.58%, respectively. It may be concluded that freezing and thawing of boar semen resulted into maximum sperm damage and electron microscopy revealed major changes in acrosome and plasma membrane which could not be seen with conventional staining procedure.

Kapil R.,Agricultural University | Sharma P.,Agricultural University | Sharma S.K.,Agricultural University | Sharma O.P.,Agricultural University | And 3 more authors.
Archives of Phytopathology and Plant Protection | Year: 2011

Pathogenic variability studies in bean common mosaic virus (BCMV) infecting common bean (Phaseolus vulgaris L.) revealed the existence of two pathogroups PG-I and PG-II and four strains (NL-1, NL-1n, NL-7 and NL-7n) in Himachal Pradesh, a North-Western Himalayan state of India. Two strains, NL-1 and NL-7 were identical to the previously described NL-1 and NL-7 strains from Europe and USA, whereas the other two designated as NL-1n and NL-7n differed from earlier identified strains with respect to their necrotic reaction on cultivar Jubila at high temperature (<30°C). Reverse phase HPLC peptide profiling of tryptic digests of coat protein of these strains further confirmed that NL-1, NL-1n, NL-7 and NL-7n are distinct from each other. This study constitutes the first record of pathogenic variability in BCMV infecting common bean in India. © 2011 Copyright Taylor and Francis Group, LLC.

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