Red Dye Solution Research Articles

The Effect of Certain Coal-Tar Dyes Used for Semen Identification on the Livability and Fertility of Bull Spermatozoa

Summary Experiments were conducted to determine whether certified coal-tar dye solutions could be used to color diluted semen in order to reduce errors in its handling. Red, green, brown, and purple color preparations were tested, under laboratory and field conditions. Spermatozoa in diluted semen colored at the rate of one drop of the basic red, green, brown, and purple dye solutions for each 10 ml. of diluter maintained their motility as well as those in the uncolored controls. In a field study, when the same dyes were used at a lower concentration, no significant differences in fertility were found between the colored and uncolored semen samples. This investigation involved 2,995 inseminations and an average of 59.9 cows were inseminated per semen sample. The results obtained demonstrate that the coal-tar color preparations described can be safely used as a practical means of coloring diluted bull semen.