History of artificial insemination in poultry, its components and significance

Artificial insemination (AI) technology use in poultry production has enabled the rapid dissemination of genetic material from a small number of superior males to a high number of females. Excellent fertility in poultry can be obtained by AI compared to natural mating. Successful application of this technique needs good quality semen that should be inseminated very close to the sperm storage tubules in the female to obtain the optimum fertility in chicken. Since the 1950s, AI has been used in commercial poultry production, initially in Israel and Australia, followed by the USA. Doses of spermatozoa required for AI increases with storage time or that obtained from aged bird. The average volume of semen is between 0.05-0.50 ml in light chicken breeds and 0.1-0.9 ml in heavy males. In light turkeys, volume is 0.08-0.30 ml, whereas in heavy-weight males it is 0.1-0.33 ml. Quality evaluation of semen gives an indication of the male reproductive potential and is the major determinant of fertility and subsequently hatchability of eggs. Semen from cockerels contains between 3-7 billion sperm cells/ml. Among the several factors that influence the semen quality, sperm motility is a primary determinant of fertility in domestic fowls; however, visual examination of semen cannot be ignored for successful AI under field conditions. Dilution of low and viscous volume of avian semen is essential for handling and storage, and chicken semen typically requires a two to three-fold dilution. Collected samples should be preserved at 2-8°C for avian species, ideally with turkey sperm stored at 4-8°C, and chicken semen at 7-8°C for good fertility. Currently, the technique of AI in most of the poultry species is well developed; however, there is a need for successful development programme of this technique in non-domesticated birds to assist in creating viable, self-sustaining populations of critically endangered species.