Artificial insemination can be traced back to the 1800’s in humans and then later into the1900’s with animals such as dogs and cows. Artificial insemination (AI) is the process of collecting sperm cells from the male and manually disposing them in to the reproductive tract, the cervix, fallopian tubes, or uterus, of the female to allow reproduction without there being any sexual intercourse between either male or female. As technology advanced, being able to understand the process became the new curiosity. The early and mid 1900’s brought answers to many of the questions that arose. In the 30’s was the first trials where egg yolk was used to protect bull sperm cells from temperature shock upon cooling. This protection was explained by the effect of phospholipids and lipoproteins in the egg yolk. It then continued into the 40’s with advancing technology by improving the media by using egg yolk with sodium citrate, permitting the use of semen at 5° C for up to three days. Then in the 50’s Cornell University scientists discovered the benefit of antibiotics added to the sperm solutions in the AI process. It was called the “Cornell extender” ,and it was the mixture of penicillin, streptomycin, and polymedia B. Though the mixture is not still used today, it was used for several years and the idea of antibiotics in the solution are still used for protection against possible contamination to sperm cells. It was not until the mid 1950’s that it was found and demonstrated the first time sperm was frozen, thawed, then used to fertilize an egg, and allowed for its normal development. Human artificial insemination, though was being practiced, was not made public because it was deemed that it went against public policy and good morals. It soon lost its popularity amongst the public because of the cramping, infections, and other pains that it would cause the female. Scientist continued with research and found ways to combat the issues. Their findings include timing and manipulation to the hormone levels along with what is occurring during each period of the cycle.
In the 1970’s the popularity of artificial insemination only shifted from humans to animals. It was easier to practice artificial insemination on animals such as dogs or chickens because of higher litter count or shorter gestation periods. Finding were able to advance and changes were able to be made at a much higher rate. With cattle, it is common to only have one calf per pregnancy and the gestation period is approximately 283 days. Despite the numbers, cattle producers seem to be divided about artificial insemination. The process has reaped both advances and setbacks.
There have been new breeds that have come from only the process of AI. In the 1940’s, the Santa Gertrudis was the direct result of artificial insemination in cattle. Though this was a huge breakthrough in science and in cattle breeding, it would take over a decade for this process to make any improvements. During that same time, the egg solution was discovered and it was used to save bull semen in order to freeze for later. This then led for the discovery of genetic modification and test where we learned how to distribute genetic material. Artificial insemination has had a major impact on the cattle industry, mainly the dairy industry. In 1970, farmers bred more than 7 million dairy cows. For many producers, there are four major benefits that come from artificial insemination. AI allows for genetically superior sire’s semen to be used without the bull needed to be present. Being able to collect the sperm before insemination allows for the sperm to be counted for fertility and tested for diseases that can be genetically carried. For dairy and beef farmers, it allows for there to be no need for a bull to be kept on the property. Bulls can sometimes be aggressive and possessive. Without the bull near the heifers and cows, this can allow for a safer environment for the farmers and workers. The biggest factor that farms like about artificial insemination is that it assists in record keeping.
The prep for AI will vary from farm to farm. Various methods include watching the females for when they “jump” each other, hormone injections, and cleaning the cervix thus allowing for the 21 day cycle to start from day one with the farmer tracking from day one. Though these are effective methods, they are not guaranteed to work. For the “jump” method, you must bring them in and AI right away. Females go into heat once every 21 days, and are only in heat for 24 hours. If artificially inseminated to early the sperm may not survive long enough, and if it is done later than what is needed, then the farmer has lost money. Sperm and semen handling can also be something that will have an effect on the production outcome. The most common ways for semen collection are whether it may be through an artificial vagina, false mounting, or electro ejaculation. The methods do not affect the outcome of the AI process, but handling after collect is a very important. Drastic changes in temperature can kill sperm cells and decrease the fertility rate. Semen is frozen in a tank of liquid nitrogen, when it is time to remove the straws, it must be a quick process. When removing the straws the lid should not be picked up higher than the frost line and you only have about ten to fifteen seconds to remove the straw or straws from the can. It then has to be placed in warm water to thaw the semen. The water must not be to hot or cold in order to properly thaw out the straw and it must not remain in the water for long. Once a straw is removed and thawed it cannot be placed back and frozen again.
There needs to be a stress free environment for the cow or heifer. Everything from the weather to the handling can affect the outcome. This is one reason why some farmers may be hesitant to use an AI program in what is essentially their small business. Many small farms do not have the proper skill set to AI their own herd nor do they have to proper equipment. This brings up both the stress level in the animals and the cost to the producer. Being able to maintain and eliminate stress related factors in the heard is something that can cause a lot of AI programs to fail. It can cost anywhere from six to twenty dollars per head to inseminate depending on the method of prep, plus the cost of the semen. The higher the quality the higher the price. A cost that may get over looked is labor. The larger the production, the more hands that are needed to maintain and move cattle. At a fifty-five to sixty percent chance of conception, the average AI program can roughly cost sixty to sixty-five dollars per born calf. Though artificial insemination programs can be costly, the cost of a bull will change as the prices in the cattle industry change no matter the quality of genetics. Compared to the cost of a straw of semen, which will hold its value no matter the fluctuation of the industry.
Though the process of AI is available for most domesticated livestock, it is still associated mainly with dairy cattle because each cow or heifer is handled as an individual on a daily basis. Compared to beef cattle in large numbers, it is easier to monitor a dairy cows cycle. Its popularity throughout the dairy industry is because it has allowed for genetic modification to increase milk production per cow, sex selection for replacement heifers, and allowed for there to be no need for a bull. Artificial insemination if favored in developing because it allows for a farmer with only one heifer or cow to improve their stock over time. The achievement of developing a simple, non-surgical insemination procedure has allowed for continuous exploration in the technology.
Though the process of artificial insemination has had some major improvements, it has only been available to the public since the early 1990’s. One of the main focuses now is on being able to take the process out-side of the lab and into the hands of the farmers and producers but easier and less expensive. It is shown that simple things such as sperm quality, fertilization timing, and hormone levels can have a major effect on the chance of an effective artificial insemination process. Science and technology is constantly improving and growing, and now with it being taken into developing countries, it is allowing for on-site changes to be made to better the process. The downside of inconsistency can be changed with proper training and handling for both animals, equipment, and semen. Though artificial insemination has only been around for about 2 decades, the process of AI and outcome is strictly depending on the attention to detail from the producer.