Boar spermatozoa survival rate in different selected commercial extenders for artificial insemination

The aim of this study was to compare preservation ability of 6 commercial extenders - Androhep, Androstar, BTS, Kare, M III, and MRA - by means of spermatozoa survival test. The semen of 18 boars was diluted with all extenders at the same time. The samples of diluted semen - dilution rate I + 4 and I + 8, were stored at a temperature 16 +/- 1 degreesC for 7 days after the semen collection. A thermo - resistance test was performed on 4 ml samples kept at 37 +/- 1 degreesC in water bath each day of the storage and microscopic evaluation of the spermatozoa survival rate was performed at the 1st, 3rd and 5th hours during incubation. The survival rate decreased parallelly with the storage length. Besides the extender Androhep and BTS we ascertained significant differences in the sperm survival rate according to the dilution rate. The extenders Androhep and BTS appear to be successful media for a higher boar sperm dilution rate. Further to this, the extra cellular sperm aspartate aminotransferase (AAT) activity was evaluated on the 3rd and 7th. day of storage. The AAT activity was measured reagent Set for determination of catalytic concentration of AAT in serum - produced by Lachema Brno. The correlation between sperm survival rate and the AAT activity was greater at a hip-er proportion of diluters used. The differences in the values among the tested extenders were on statistical significant levels (P < 0.05 and P < 0.01) when the survival rate of boar sperm and AAT activity were tested. In this experiment the best sperm survival rate of the boar spermatozoa was detected in Androhep extender (P <0,05 and P<0,01).