Cryopreservation of buffalo (Bubalus bubalis) semen in Bioxcell extender.

This study was designed to compare commercially available extender Bioxcell with tris-citric egg yolk extender for post thaw quality and in vivo fertility of buffalo semen. For comparison of post thaw semen quality: semen was collected from five adult Nili-Ravi buffalo (Bubalus bubalis) bulls of similar age group with artificial vagina (at 42 degrees C) for three weeks (replicates). Qualifying ejaculates having motility >60% from each buffalo bull were divided in two aliquots and diluted (at 37 degrees C having 50 x 10(6) spermatozoa/ml) in tris-citric egg yolk or Bioxcell extender. Diluted semen was cooled to 4 degrees C in 2 hours, equilibrated for 4 hours and filled in 0.5 ml straws. Semen straws were kept over liquid nitrogen vapors (5 cm) for 10 minutes. Straws were then plunged and stored in liquid nitrogen (-196 degrees C). After 24 hours of storage, semen straws were thawed at 37 degrees C for 30 seconds to assess sperm motility, viability, plasma membrane integrity, normal apical ridge, and abnormalities (head, mid piece, and tail). For comparison of in vivo fertility: semen from two buffalo bulls of known fertility was cryopreserved in tris-citric egg yolk and Bioxcell as described earlier, and used for inseminations under field conditions. Post-thaw percentage of sperm motility (45.3 +/- 1.1, 45.0 +/- 1.4), viability (66.2 +/- 1.1, 64.4 +/- 1.3) plasma membrane integrity (60.4 +/- 1.2, 59.2 +/- 1.4) and normal apical ridge (82.9 +/- 0.5, 80.7 +/- 0.5) did not differ (P > 0.05) in tris-citric egg yolk and Bioxcell extender, respectively. Similarly, sperm abnormalities of head (1.20 +/- 0.1, 1.20 +/- 0.1), mid piece (0.67 +/- 0.1, 0.87 +/- 0.1) and tail (11.7 +/- 0.2, 11.6 +/- 0.3) remained similar (P > 0.05) in tris-citric egg yolk and Bioxcell extender, respectively. In vivo fertility rates of buffalo semen cryopreserved in tris-citric egg yolk and Bioxcell also remained similar (44% vs. 47%). It is concluded that commercially available Bioxcell may be used for the cryopreservation of buffalo semen with an equal efficiency to tris-citric egg yolk extender.

Akhter S ，Ansari MS ，Rakha BA ，Andrabi SM ，Iqbal S ，Ullah N ... -  《-》

In vitro evaluation of liquid-stored buffalo semen at 5°C diluted in soya lecithin based extender (Bioxcell®), tris-citric egg yolk, skim milk and egg yolk-citrate extenders.

This study was designed to compare the quality of liquid-stored buffalo bull spermatozoa in soya lecithin based extender Bioxcell(®) (BIOX), milk (MILK), tris-citric egg yolk (TEY) and egg yolk-citrate (EYC) extender at 5°C. Semen was collected from five Nili-Ravi buffalo (Bubalus bubalis) bulls of 6-7 years of age with artificial vagina over a period of 3 weeks (two consecutive ejaculates once in a week). Semen ejaculates having more than 60% motility were pooled, split into four aliquots, diluted (37°C; 10 × 10(6) motile spermatozoa/ml), cooled from 37 to 5°C in 2 h (0.275°C/min) and stored for 5 days. Sperm motility, viability, plasma membrane integrity (PMI) and normal acrosomal ridge were studied at first, third and fifth day of storage. Higher values of progressive sperm motility (%), sperm viability (%), sperm PMI (%) and normal apical ridge (%) were observed in BIOX, MILK and TEY extenders at first, third and fifth day of storage than EYC extender. Progressive sperm motility, sperm viability and sperm PMI in BIOX(®) extender were not different from MILK and TEY extenders at 1st and third day storage period. However, at fifth day of storage, the values for these parameters remained significantly higher (p<0.05) in BIOX(®) compared with MILK, TEY and EYC extenders. At fifth day of storage, the semen quality parameters for Bioxcell(®) were comparable to those with MILK and TEY extenders at third day of storage. In conclusion, motility, viability and PMI of buffalo bull spermatozoa remained similar in Bioxcell(®) , milk and TEY extender at first and third days of storage at 5°C. Yet, the values for the aforementioned parameters in Bioxcell(®) were higher compared with milk, TEY and EYC extender at fifth day of storage at 5°C.

Akhter S ，Ansari MS ，Rakha BA ，Ullah N ，Andrabi SM ，Khalid M ... -  《-》

OPTIXcell improves the postthaw quality and fertility of buffalo bull sperm.

The present study was conducted to compare the liposome-containing, animal protein-free, commercially available OPTIXcell extender with the Tris-citric-egg yolk extender for postthaw quality and fertility of buffalo semen. Semen was collected from five adult Nili-Ravi buffalo (Bubalus bubalis) bulls of similar age group with an artificial vagina (at 42 °C) for 3 weeks (replicates). Semen ejaculates from each buffalo bull were divided into two aliquots and diluted (at 37 °C having 50 × 10(6) spermatozoa/mL) in the OPTIXcell or Tris-citric-egg yolk (control) extender. Diluted semen was cooled to 4 °C in 2 hours, equilibrated for 4 hours, and filled in 0.5-mL straws. The semen straws were kept over liquid nitrogen vapors (5 cm) for 10 minutes. The straws were then plunged and stored in liquid nitrogen (-196 °C). After 24 hours of storage, the semen straws were thawed at 37 °C for 30 seconds to assess postthaw quality. Percentages of sperm motility, plasma membrane integrity, viability, and acrosomal integrity were improved (P < 0.05) in the OPTIXcell extender compared to the Tris-citric-egg yolk extender. Values for DNA integrity (%) did not differ in the OPTIXcell and Tris-citric-egg yolk extenders. The overall conception rate in buffaloes was improved (P < 0.05) with semen cryopreserved in the OPTIXcell extender (59.5%) compared to semen cryopreserved in the Tris-citric-egg yolk extender (41.5%). It is concluded that the liposome-containing commercially available OPTIXcell extender is more efficient to conserve postthaw quality and resulted in higher fertility rate of buffalo in the field.

Ansari MS ，Rakha BA ，Akhter S ，Ashiq M ... -  《-》

Duck egg yolk in extender improves the freezability of buffalo bull spermatozoa.

We investigated the use of duck egg yolk (DEY), Guinea fowl egg yolk (GFEY) and Indian indigenous hen (Desi) egg yolk (IDEY) in extender for improving the post-thaw quality of buffalo (Bubalus bubalis) bull spermatozoa, and compared it with commercial hen egg yolk (CHEY; control). For this purpose, two consecutive ejaculates of semen from each of two Nili-Ravi buffalo bulls were collected on 1 day each week for 5 weeks (replicates; n=5) with artificial vagina (42 degrees C). Split pooled ejaculates, were diluted in tris-citric acid glycerol extender containing either DEY or GFEY or IDEY or CHEY at 37 degrees C. Extended semen was cooled to 4 degrees C in 2 h and equilibrated for 4 h at 4 degrees C. Cooled semen was then filled in 0.5 ml straws at 4 degrees C and frozen in programmable cell freezer. Thawing of semen was performed at 37 degrees C for 30 s. Sperm motility, plasma membrane integrity and sperm morphology (acrosome integrity, head, mid-piece and tail abnormalities) of each semen sample were assessed at 0, 3 and 6 h after thawing and incubation at 37 degrees C. Visual motility (%) and percentage of intact plasma membranes assessed at 6h post-thaw of buffalo bull spermatozoa were highest (P<0.05) due to DEY as compared to GFEY, IDEY and control. The percentage of spermatozoa with normal acrosomes at 0, 3 and 6 h post-thaw was highest (P<0.05) in DEY extender than GFEY, IDEY and CHEY. Sperm tail abnormalities (%) observed at 0, 3 and 6 h post-thaw in samples cryopreserved with freezing extender having DEY were lower (P<0.05) as compared to extender containing GFEY, IDEY and CHEY. In conclusion, DEY compared to other avian yolks in extender improves the frozen-thawed quality of buffalo bull spermatozoa.

Andrabi SM ，Ansari MS ，Ullah N ，Anwar M ，Mehmood A ，Akhter S ... -  《ANIMAL REPRODUCTION SCIENCE》

Effect of low density lipoproteins in extender on freezability and fertility of buffalo (Bubalus bubalis) bull semen.

This study was designed to determine whether low-density lipoporoteins (LDLs) extracted from egg yolk in extender improve the freezability and fertility of buffalo bull semen. Semen from three Nili-Ravi buffalo bulls was diluted at 37 °C with tris-citric acid extender (50 × 10(6) motile spermatozoa mL(-1)) containing LDLs 2.5%, 5%, 10%, and 15% extracted from egg yolk and extender containing 20% egg yolk was kept as control. Diluted semen was cooled to 4 °C in 2 h, equilibrated at 4 °C for 4 h, filled in 0.5 mL French straws, and kept on liquid nitrogen vapors for 10 min. Straws were then plunged and stored in liquid nitrogen (-196 °C). Sperm motility (visually; %), plasma membrane integrity (%; with supravital hypo-osmotic swelling test), and viability (%; with dual staining test using Trypan-blue Giemsa) were assessed at post-dilution, pre-freezing and post-thawing. At post-dilution and pre-freezing, sperm progressive motility, plasma membrane integrity and viability was similar (P > 0.05) in extender containing 10% LDLs or the control. However, at post-thaw the aforementioned parameters were higher (P < 0.05) in extender containing 10% LDLs compared with the control and other experimental extenders. The fertility rate of inseminations performed were higher (P < 0.05) with extender containing 10% LDLs than the control. It was concluded that LDLs (10%) in extender improved the freezability and fertility of buffalo bull spermatozoa.

Akhter S ，Ansari MS ，Rakha BA ，Andrabi SM ，Khalid M ，Ullah N ... -  《-》