The fertility properties of Brown Swiss, Holstein and Jersey breed cows in Lalahan Zootechnical Research Institute

The semen was collected from the bulls by artificial vagina. After the necessary macroscopical and microscopical inspections the best ones have been frozeen. In the dilution of the sperm Laiciphos 271 was used. The sperm was frozen in liquid nitrogen in pailliets after glycrerolisation and equilibration in 0.50 cm3 insemination dosis that would contain 25 x 106 motile spermatozoit. They have been kept in liquid nitrogen at a temparature of – 196 oC. 314 cows were inseminated recto vaginally by frozen sperm.

From the 102 Brown Swiss cows that have been inseminated 78 of them have became pregnant. The percentage of pregnancy was 76.4 %. In the first insemination the nonreturn pregnancy was 64.7 %. The number of insemination for each pregnancy was 2.0. From the pregnant 91.0 % of them gave birth to a calf. The rate of abortion was 5.1 %. And the rate of difficult birth was 3.8 %. The percentage of sterile cows was found to be 23.5 %. The duration of the pergnancy of the Brown Swiss cows was 287.5.

Within the 3 years the rate of pregnancy was found to the 77 % in 161 Holstein cows. İn the first insemination non-return pregnancy percentage was 60.2 %. For each pregnancy the number of insemination was 2.1. The rate of abortion was 3.2 %. The rate of difficult birth was 4.8 %. The rate of sterility was 22.9 %. The duration of pregnancy of the Holstein cows was found to be 280.3 days.

From to 51 Jersey cows that have been inseminated 38 of them have become pregnant. The percentage of pregnancy was 74.5 %. Out of 74.5 %, 49 % pregnancy percentage have been obtained from the firs insemination for each pregnancy was 2.2 %. From the pregnant cows 89.4 %. Of them normally gave birth to a calf. The rate of abortion was 10.5 %. There werent any difficult-birth. Of the cows that have been inseminated 25.5 % of them have become sterile. The duration of the pregnancy was 277.0 day. Keywords :