Semen Handling for Maximum Fertility
Published on Tue, 11/26/2019 - 10:08am
Semen Handling for Maximum Fertility
By Jaclyn Krymowski
A good part of your pregnancy rate hinges on the individual bull and quality of semen you use. It takes two to tango, after all. While a simple procedure in principle, A.I. is filled with numerous intricacies. It requires a certain gamble putting a substance as delicate as semen into very unnatural circumstances and handled repeatedly. Even slight mishandling can have a negative impact on chances of successful pregnancy. Your goal is to do everything possible to keep the greatest odds in your favor. There’s a lot you can do to manipulate the cow and set her up for success, but there is also plenty on the bull’s end of the deal.
Certain elements are beyond your control before you even have the unit in your tank. How the semen is collected, processed and handled by the distributor are all critical factors. Companies do the best they can to deliver a high-quality product to dairymen, but even the best care beforehand will only do so much if handled poorly on the farm. There’s even variation from bull to bull and collection to collection on semen potency and sensitivity to the environment.
Common handling errors
Storage temperature, placement and thawing are among the most crucial elements to maximizing fertility. Overlooking even one of these can result in sperm damage and failure to fertilize. Semen stores successfully at -270F. Sperm is impacted immediately upon removal from this environment at which you must be committed to completing the thaw and sustaining the temperature until deposited into a cow.
The typical thawing recommendation is a warm water bath of 95-98F for 45 seconds. Some studies have shown that thawing in a cold-water bath preserves fertility just as well. Usually it’s best to speak with your distributor and see what their recommendations for thawing are based on how they process their semen. Pocket thawing is typically not recommended as it can seriously damage fertility. Likewise, thawing multiple units in a warm water bath also runs a risk as decreasing fertility as there is a chance of the temperature dropping and not able to sustain them all. In such a case, water must be warm enough so that the units will not dilute the temperature too much.
Retrieval is another major area where semen is mishandled and damaged. Semen that is exposed to warmer temperatures, even momentarily, is subject to damage from premature thawing. And once any thawing begins, refreezing cannot happen without further damage. A canister should not be held above the frost line in the neck of the tank for more than 10 seconds. This can happen when breeders are improperly trained and spend too long looking for the correct unit. The rule should always be if it takes longer than 10 seconds, the canister must be returned below the frost line before tried again. For similar reasons, it is not recommended to use bear hands to handle straws. It may be a bit less convenient, but tweezers are the best way to ensure semen is uninhibited by any excessive warmth.
Sperm cells, being very sensitive to foreign contaminates, can be killed by contact with water and other substances. Most breeders are careful to only use non-spermicidal lubricants for A.I. However, missing something as simple as completely drying a sheath or rod can leave enough water droplets left to have an impact. Sunlight is another enemy of viable sperm. When transporting loaded rods, be especially vigilant to avoid keeping them in direct sunlight. Keeping them in a pocket or shirt does this and also keeps the semen warm before depositing into a cow.
The final stage where semen is still subject to mishandling damage is ultimately in the hands of the breeder when the unit is deposited into the uterus. Pushing the plunger too fast and forcefully can be damaging. A proper training will instruct the breeder to slowly and delibtrately deposit the semen.
A team effort
One of the best ways to ensure constent quality of semen and maximize success rates are the efforts from everyone on the team. Depending on the size of your dairy, it may pay to have an employee or two take a profressional A.I. course from a stud company. A lot of them will even offer “refresher” classes after the initial certification. Proper semen handling should be stressed and procedures kept consistent across the board. Even those who aren’t involved in the physical breeding but may handle A.I. tanks or thawing units should have a thorough understanding of the breeding process and the nature of frozen semen.
Established breeding protocol and standard operating procedures are also helpful in pinpointing problems as you track pregnancy success rate with your individual breeders.
A lot of semen care and handling is common sense, a mundane list of things breeders have heard time and time again. But taking sloppy shortcuts and cheats are subject to even the best of us from time to time. The more people involved in your breeding program, the greater likelihood of these happening. A little vigilance, with the aids of continuing education and enforcement, is a cheap of always making the most of valuable semen.