Buffalo anti-PDC-109 antibodies improve the semen quality profiles and in-vitro zona binding index and minimize the cryoinjury of sperm in cryopreserved buffalo semen

Objective:To optimize the concentration of PDC-109 protein in semen for higher cryopreservability and fertility by sequestration or neutralization of PDC-109 by its antibodies(anti-PDC-109 antibodies)in bubaline species.Methods:PDC-109 protein was purified by applying two-step chromatography procedures.Purified protein was injected in rabbits to raise antibodies.These raised anti-PDC-109 antibodies were used in neutralization or sequestration of PDC-109 in in-vitro model.Ejaculates were collected from buffaloes and splited for four groups.Group 1 received egg yolk Tris glycerol extender,without anti-PDC-109 antibodies,while group 2 to 4 received anti-PDC-109 antibodies 266μg/mL,80μg/mL,and 26μg/mL in Tris-fructose-citrate buffer,respectively.Semen quality parameters viz.,forward progressive motility,viability,total morphological abnormality,acrosomal integrity,plasma membrane integrity,cryoinjury and in-vitro zona binding index were evaluated.Results:Semen quality parameters of neat semen were within the normal range of bubaline species.Sperm motility,livability,acrosomal integrity,plasma membrane integrity,and cholesterol content of sperm were decreased and total sperm abnormality was increased significantly in post-thaw semen compared to those in pre-freeze and fresh semen(P<0.05).Semen in group 2 had higher sperm motility,livability,acrosomal integrity,plasma membrane integrity,and cholesterol content of sperm and lower total sperm abnormality significantly compared to those in group 1,3 and 4 at pre-freeze and post-thaw stages(P<0.05).Conclusions:Sequestration or neutralization of PDC-109 by its antibodies significantly improves pre-freeze,and post-thaw semen quality parameters and in-vitro zona binding index with simultaneously reducing cryoinjury or cryodamage in the sperm of bubaline species.

Effect of multiple rings on side force over an ogive-cylinder body at subsonic speed

Experiments and computations were performed over an ogive-cylinder body having an lift-to-drag ratio of 16 at a diameter Reynolds number of 29000. The side force on the slender body augments with increasing angles of attack for the case without a ring. This increase was mainly due to the increase in the asymmetry of the existing vortex pair in the wake of the body. Attempts were made to completely reduce the existing side force at the angle of attack ranging from 35° to 45°.Three rectangular cross-sectioned circumferential rings having a height of 3% of the local diameter were placed at axial distances of 2.5, 3.5 and 4.5 times the base diameter from the tip of the body so as to reduce the side force. The results obtained indicate that inclusion of three rings completely alleviated the side force on the slender body at the angle of attack ranging from 0° to 45°. The presence of rings was found to alter the growth of the vortices that helped in the reduction of the side force. Computations performed were in reasonable agreement with the experiments.