New Mexico Youth Ranch Management Camp Beef Day June 1, 2015 Artificial Insemination and Embryo Transfer Steve M. Lucero 4-H Agriculture Agent Sandoval County Cooperative Extension Service ARTIFICIAL INSEMINATION The deposi5on of sperm in the female genitalia by ar5ficial means. The history of A.I. • It may have been used as far back as 1322, at which 5me an Arab chieKain used ar5ficial methods to impregnate a prized mare. • The first scien5fic research rela5ve to A.I. in domes5c animals was conducted with dogs by the Italian physiologist Lazarro Spallanzani. • It was first used commercially in caMle in the U.S. in 1938. • Currently A.I. is widely practiced with dairy (60%) and approximately 6% of beef animals. Sandoval County Cooperative Extension Service Advantages of Using Ar0ficial Insemina0on: • It increases the use of outstanding sires. • There is a selec5on advantage by using A.I. with top bulls. • It controls diseases by -‐ assuring use of semen from healthy bulls, thus reducing the spread of venereal diseases such as vibriosis, which causes cows to abort their calves. • Calving ease. • Controlled/5med breeding. • Accurate due date. Sandoval County Cooperative Extension Service Semen Tank Management • The inner chamber containing liquid nitrogen is actually suspended from the outer shell by the neck tube. • Any abnormal stress on the neck tube caused by sudden jarring or an excessive swinging motion can possibly crack the tube resulting in vacuum loss from the outer chamber. • Accumulation of frost at the top of the tank indicates a rapid evaporation of liquid nitrogen. Sandoval County Cooperative Extension Service • Store the semen tank in a well lighted area but out of direct sunlight. • Keep the tank elevated above the concrete floor or other wet and poorly ventilated surfaces. • Corrosion of the outer shell shortens the functional life of the tank and possibly causes tank failure. Sandoval County Cooperative Extension Service Temperature Found in the Neck Tube of a Typical Farm Semen Tank _____________________________________________________________________________________ Location in Necktube Range in Temperature . Top 1 inch from top 2 inches from top 3 inches from top 4 inches from top 5 inches from top 6 inches from top +36°F +5° –40° –103° –148° –220° –292° to to to to to to to +54°F –8° –51 ° –116° – 184° – 256° – 313° ________________________________________________________________________________________________________________________________________ Adapted from Saacke 1978, Proc. 12th Conf. on Al of Beef Cattle. . Critical danger zone is the upper half of the neck tube or above –112°F * Holding semen in this danger zone for more than a few seconds can decrease fertility Sandoval County Cooperative Extension Service Handling Semen Within the Tank • Coordinate rapid transfer of semen between tanks. Involve two people and arrange tanks side by side. • If possible fill the tanks with nitrogen before transfer. • Raise canisters only to a level necessary to locate the rack of semen to be transferred. • Maintain a record keeping system. Sandoval County Cooperative Extension Service Thawing Semen • When preparing to thaw semen raise the canister into the lower portion of the neck where the specific rack of semen can be grasped. • Lower the canister further into the neck. Secure the rack as low as possible in the neck, thus protecting the other straws from thermal damage. Sandoval County Cooperative Extension Service • Use tweezers to transfer the straw to the thaw bath. • Quickly lower the rack of semen and canister into the body of the tank. • The straw is pulled from the cane and deposited into the warm water bath that is 90-96 degrees, and left for 35 to 60 seconds. • It is then wrapped in a paper towel and shaken so the sperm is on one end and an air bubble is at the other. Sandoval County Cooperative Extension Service • Do not attempt to thaw semen at temperatures greater than 95°F (35°C). • Thaw units of semen individually. • Shake the straw as it is taken from the tank to remove any liquid nitrogen that may be retained in the cotton plug end of the straw. • Thoroughly dry each straw of semen. Sandoval County Cooperative Extension Service • Cut the tip of the straw squarely and through the air space below the crimp. • An angle cut may prevent the straw from fitting securely into the sheath. Sandoval County Cooperative Extension Service Loading Insemination Gun Eliminate the chance of cold shock by: 1. Warming the inseminating rod and sheath to body temperature (do not use water for this purpose). 2. Handle the thawed semen and prepare the insemination rod in a warm environment. 3. Wrap the assembled insemination rod in a clean, dry paper towel and tuck it within your clothing for transport to the cow. Sandoval County Cooperative Extension Service Insemination Process • Inseminate the cow within a few minutes (no more than 15 minutes) after the semen has been thawed. • The gloved arm is inserted into the rectum and the cervix grasped. • The outside of the cow’s reproductive tract should be wash before insemination. This prevents the introduction of manure and other contaminants to the reproductive tract. • The insemination rod is then introduced into the vulva at a 30-40˚ then horizontal into vagina and passed through the cervix into the uterus (at cervical os). • The semen is deposited slowly over a 5 seconds. Sandoval County Cooperative Extension Service Proper Semen Placement Radiograph of an excised cow reproductive tract. Source: Pennsylvania State University Sandoval County Cooperative Extension Service Proper placement of the insemination rod tip at the internal cervical os. Source: Pennsylvania State University Sandoval County Cooperative Extension Service Distribution of radiopaque semen within the uterine body. Source: Pennsylvania State University Sandoval County Cooperative Extension Service Improper rod placement in the right uterine horn. Source: Pennsylvania State University Sandoval County Cooperative Extension Service Radiopaque semen deposited in the right uterine horn. Source: Pennsylvania State University Sandoval County Cooperative Extension Service Heat Detection and Timing • Standing heat occurs every 18-24 days, and lasts for about 15 hours (range 6-24 hours). • Timing is imperative when AI-ing a cow, to achieve the highest rate of conception, a cow seen standing in the am will be AI-ed in the pm, and if seen in the pm will be AI-ed in the am. • This is done because the cow ovulates after the onset of standing heat (24-32 hours). Sandoval County Cooperative Extension Service Heat Detection • This is the most limiting factor in an AI program. • The cow or heifer must be seen in standing heat or active Estrus, this is indicated by an altered behavior. • The female that is in “heat” will become immobile when another animal, bull or cow, mounts her. Sandoval County Cooperative Extension Service Are you spending more and gambling on un-proven genetics? Source: ABS, Beef Focus Point, Spring 2015 Sandoval County Cooperative Extension Service Are you spending more and gambling on un-proven genetics? Source: ABS, Beef Focus Point, Spring 2015 Sandoval County Cooperative Extension Service What is Embryo Transfer? ET involves the removal of an embryo from a female of superior genetics and the placement of the embryo into the reproductive tract of a female of average genetics. Sandoval County Cooperative Extension Service What is the Goal of Embryo Transfer? The goal of ET is to obtain the maximum number of genetically superior embryos in a minimum amount of time. Sandoval County Cooperative Extension Service Benefits of Embryo Transfer • Traditionally, cows produce only one calf per year. ET allows the production of many offspring within a year from a single cow. • ET can increase the genetic potential of a herd in a relatively short period of time. • ET allows other producers to take advantage of superior genetics because frozen embryos can be shipped almost anywhere. • ET preserves superior genetics for future generations due to embryo freezing. Sandoval County Cooperative Extension Service Embryo Size and Quality Embryos are microscopic in size (about 0.2 mm). Only undamaged embryos at proper maturity should be transferred or frozen. The embryos on the left are damaged and should not be transferred. The embryo on the right is of proper maturity and quality and should be transferred. Sandoval County Cooperative Extension Service Steve M. Lucero Sandoval County Cooperative Extension Service P.O. Box 400 Bernalillo, NM 87004 1-800-678-1802 or 505-867-2582 [email protected] Sandoval County Cooperative Extension Service
© Copyright 2024