Influence of Adding Manganese to Tris Extender on some Post-Cryopreservation Semen Attributes of Holstein Bulls

This study was conducted to explore the adding effect of manganese (Mn) to Tris extender on post cooling and cryopreservation semen attributes of Holstein bulls for different periods. Seven Holstein bulls of 3.5-4.5 years old were used in this study. Pooled semen was divided into three groups. The first group was diluted with Tris only (control group, G1). While the 2 nd (G2) and 3 rd (G3) groups were added 0.7 and 0.9 mM Mn +2 respectively. The effect of these additions on Holstein bulls semen quality was studied during different periods (cooling at 5 Celsius, 72 hrs.,1 st , 2 nd and 3 rd post cryopreservation, PC). Addition of Mn +2 led to significant increases of total (×10 6 ) plasma membrane integrity of sperms and total function sperm fraction as compared with control groups during cooling and PC periods. It can be concluded that the addition two levels of acid Mn +2 led to enhanced PC semen quality of bulls. This will in turn improved fertility rate of cows and owner's economic income.