You may be considering ordering artificial insemination (AI) straws in the coming weeks ahead of breeding, but have you checked on your liquid nitrogen tank?

As every farmer knows, once the AI straws land in the yard, they will need to be stored in tanks of liquid nitrogen at a temperature of -196ºC to preserve the semen.

To maintain this temperature, while also upkeeping safety around dangerous liquid nitrogen, the tanks' integrity must be maintained.

Like everything, storage tanks are susceptible to damage from mishandling, which can lead to wasted straws if the temperature is not right, and they are not cheap these days, especially when using sexed semen.

Worst of all, if there is an unknown issue with the tank and the sperm is not being preserved properly, farmers may have conception issues without knowing why.

Liquid nitrogen tank

Given how hectic this time of the year is for dairy farmers, it is easy to overlook tasks like this and not give the tank the maintenance or inspections it requires.

Therefore it may be a good idea before straws land in the yard to book in a service with your local AI comapny.

Even after a service, farmers should keep an eye out for any frosting or condensation building up on the tank.

If this is happening, the tank needs to be replaced immediately as it has more than likely lost its vacuum and the liquid nitrogen is evaporating at an accelerated pace, which is dangerous in terms of gasses as well as lost semen.

In this scenario, or if any other damage has been caused to the tank, it may be worthwhile having your AI company test the semen to ensure it is still alive after been moved to a new tank.

Another issues that can damage the integrity of the semen is having the tank open for extended periods while searching for a particular straw.

That is why you should have a list of each straw/sire, and its location within the tank, so you can quickly fetch it with the forceps.

Costs

New storage tanks cost in or around the €600 mark, while storage boxes have been priced around €220-€250, meaning the setup can be got for a total of €850 (varying on supplier).

Once the tank has been installed, your local genetics supplier will carry out annual liquid nitrogen services, where they refill the tank.

This is typically quoted in around the €100 mark, but prices vary.

Despite annual services, the tank should be checked weekly for liquid nitrogen levels, the tank should not be allowed to drop below one-third full, nor should it be overfilled.

The tanks are generally rated to hold liquid nitrogen for six months or more, however this varies on the individual tanks, as well as how often it is opened, which can be quite often during the breeding season.

If you notice levels dropping on the dipstick during the breeding season or are having any issues, an emergency call-out fee can be anywhere between €150-€200.