**2. First developments and milestones in the field of veterinary Artificial Insemination**

Artificial insemination (AI) was the first assisted reproductive technique applied to control and improve reproduction as well as genetics. The first successful insemination was performed by the Italian physiologist and priest Abbe Lazzaro Spallanzani (1784) in a dog which whelped three pups 62 days later (Foote, 2002). The establishment of AI as a practical procedure was initiated in Russia in 1899 by Ivanov who studied AI in domestic farm animals, dogs, foxes, rabbits and poultry. He also developed semen extenders. Milanov, another Russian scientist and successor of Ivanov, started large scale breeding programs for cattle and sheep, and designed and made artificial vaginas. Horse breeding programs and research was initiated at the same time in Japan even though translations of the original research only became available to the western world after 1958. Some AI work, especially in horses and cattle, had been done in Denmark in the early 1900s. It was Danish veterinarians who established the method of rectovaginal fixation of the cervix for insemination in cattle which enabled semen deposition deep into the cervix or into the uterine body (Foote, 2002). This technique is still used today. Another Danish invention was the straw for packaging semen. These straws have been further developed and modified by the French and are now used worldwide for processing and storage of frozen semen. Research on artificial insemination in Italy led to the development of an artificial vagina for dogs in 1914 and to the establishment of the "International Congress on AI and Animal Reproduction" in 1948. This congress is held every four years since (Foote, 2002). Rapid development of AI in dairy cattle occurred in the USA in the 1940s. One of the important milestones was the establishment of the "Dairy breeding research centre" on the campus of the Pennsylvania State University in 1949 to assist in the development of artificial insemination in dairy cattle. Interest in and development of frozen semen started with successful cryopreservation of gametes from a variety of animal species after discovery of the protective action of glycerol by scientists in Cambridge, England, in 1949 (Amann & Pickett, 1987). Early research focused on bull spermatozoa; methods successful to cryopreserve bull spermatozoa have

facilitated. Other important aspects are the prevention of venereal disease transmission that plays a major role in the economic system of offspring production, and increased safety for

Venereal diseases that play a major economic role in cattle production are for example Trichomonosis and Campylobacteriosis both of which decrease reproductive efficiency through decreased pregnancy rates, high return rates to estrus and increased pregnancy losses. In general, shipping fresh and frozen semen nationally and internationally involves

Import and export of frozen semen is a huge economic market. Semen of a specific bloodline, a specific individual male or breed is imported. This is especially important in countries where breeds were introduced and are somewhat isolated with a small genetic pool. To eventually prevent breeding setbacks due to inbreeding and to expand the genetic pool, imported semen is used. Furthermore, AI can be used for frozen semen from males that have died or are not physically available for matings due to distance or physical inability. A great advantage of frozen semen in general is that it can be stored indefinitely

**2. First developments and milestones in the field of veterinary Artificial** 

Artificial insemination (AI) was the first assisted reproductive technique applied to control and improve reproduction as well as genetics. The first successful insemination was performed by the Italian physiologist and priest Abbe Lazzaro Spallanzani (1784) in a dog which whelped three pups 62 days later (Foote, 2002). The establishment of AI as a practical procedure was initiated in Russia in 1899 by Ivanov who studied AI in domestic farm animals, dogs, foxes, rabbits and poultry. He also developed semen extenders. Milanov, another Russian scientist and successor of Ivanov, started large scale breeding programs for cattle and sheep, and designed and made artificial vaginas. Horse breeding programs and research was initiated at the same time in Japan even though translations of the original research only became available to the western world after 1958. Some AI work, especially in horses and cattle, had been done in Denmark in the early 1900s. It was Danish veterinarians who established the method of rectovaginal fixation of the cervix for insemination in cattle which enabled semen deposition deep into the cervix or into the uterine body (Foote, 2002). This technique is still used today. Another Danish invention was the straw for packaging semen. These straws have been further developed and modified by the French and are now used worldwide for processing and storage of frozen semen. Research on artificial insemination in Italy led to the development of an artificial vagina for dogs in 1914 and to the establishment of the "International Congress on AI and Animal Reproduction" in 1948. This congress is held every four years since (Foote, 2002). Rapid development of AI in dairy cattle occurred in the USA in the 1940s. One of the important milestones was the establishment of the "Dairy breeding research centre" on the campus of the Pennsylvania State University in 1949 to assist in the development of artificial insemination in dairy cattle. Interest in and development of frozen semen started with successful cryopreservation of gametes from a variety of animal species after discovery of the protective action of glycerol by scientists in Cambridge, England, in 1949 (Amann & Pickett, 1987). Early research focused on bull spermatozoa; methods successful to cryopreserve bull spermatozoa have

valuable breeding animals as mating related injuries are avoided.

and has the potential to outlive the male donor animal by years.

**Insemination** 

fewer health risks and welfare implications than transporting live animals.

been less successful for other species. Barker and Gandier reported the first pregnancy from frozen stallion semen in 1957 (Barker & GaPndier, 1957). Poor pregnancy results with the use of frozen-thawed stallion semen limited research funding for breeding trials in this species (Amann & Pickett, 1987). Only later the Chinese inseminated more than 110'000 mares with frozen-thawed stallion semen (between 1980 and 1985). The United States also did not have interest in developing improved procedures for freezing stallion spermatozoa in the seventies. Only in 1980 the Animal Reproduction Laboratory of Colorado State University began a long-range research program aimed at developing satisfactory procedures to freeze stallion semen. The acceptance of frozen semen as a method to produce registered foals by two of the largest breed associations, the American Quarter Horse and the American Paint Horse association in 2001 has furthermore stimulated new interest in the frozen semen technology (Loomis, 2001).
