Importance of semen cooling: what approaches to take?
There are two important steps for optimizing the conservation of boar semen over time: adding extender to the semen as soon as possible to stop bacterial development and a conservation around 17 degrees to keep the spermatozoa at rest. This article focuses on the second step.
Why store semen at 17 degrees Celsius?
When the ejaculate arrives in the laboratory, it is usually at a temperature of around 30 degrees. When the extender is added, its temperature must also be around 30 degrees to avoid any thermal shock, which is harmful to the spermatozoa. This semen must then be cooled to approximately 17 degrees. This drop in temperature slows down the spermatozoa metabolism (we can speak of “making the spermatozoa drowsy”), which reduces their energy consumption and thus gives improved conservation over time. All this energy saved will be fully used during the heating of the semen at the time of insemination.
Semen cooling
As previously mentioned, it is essential to cool the semen to a temperature of 17 degrees to optimize its conservation. The most effective way to do this is to have the entire laboratory air-conditioned to this temperature. Don’t forget to have the air conditioning serviced every year to make sure it is working properly. In any case, it is advisable to spread the doses on shelves to ensure proper cooling by enabling good air circulation to cool the semen efficiently. Arrange the doses in open-work recipients to facilitate the circulation of air and thus the cooling of the semen.
During days of heavy workload, or in places where regulating the temperature is fairly complicated and temperatures can quickly rise, it is preferable to foresee systems such as the ones on this photo. Indeed, in this boar stud, the temperatures can be quite high in summer, and the air conditioning does not manage to regulate the temperature properly. The doses are then spread out individually on a trolley per row (where for organizational reasons each row can receive 8 doses). Each trolley leaving the production area arrives in an “isolated” room, where the doses are placed in front of a fan that moves the air conditioned air. In this way, cooling system is fast and efficient to ensure the quality of the dose. Each center must adapt according to its technical constraints. But in all cases, it is essential that the doses are cooled as quickly as possible to a temperature of 17 degrees, and that they are then stored at this temperature as well.
Extension of conservation in the transport trucks
Do not neglect the transport stage regarding semen conservation. Indeed, temperature variations strongly impact semen quality.
So, try to use air-conditioned vehicles as much as possible. If it is not the case, then use isothermal boxes (as on this picture) for long haul transport, especially in summer when it is very hot. We also advise you to check the temperature in the transport vehicles randomly and regularly to ensure the right temperature.
From now on, do not neglect the importance of cooling your boar semen doses. Feel free to inquire about our semen storage unit on GenePro website.
