What is Kilhams?

The Kilham virus is one of the parvoviruses that affect rats. Although unconfirmed through ELISA testing, some breeders of the imported rats in South Africa have experienced fertility problems which may have been caused by the Kilham virus. Because animals display no symptoms of the virus until bred, infected animals may have passed quarantine. It is usually not a major issue because flare-ups in the ratteries are rare and breeding usually resume after 2-3 months.

It does not affect pet owners or any non-breeding colony as it only has an influence on fertility, but it may be devastating to large scale breeders or rodent farms who continuously breed rats in large numbers and who acquired the imported varieties in the last two years.

SIGNS OF YOUR COLONY POSSIBLY INFECTED BY THE KILHAM VIRUS:

• Females have difficulty conceiving.

• Reabsorption of pups. (Usually sudden weight loss during pregnancy)

• Small litters due to low fertility.

• Runting of pups.

• Pups that fail to thrive.

• Still born pups.

The virus is transferred in utero, through the mothers’ milk and direct contact with an infectious rat. The virus may survive for several weeks or even months in the environment. If no breeding takes place for several months, the virus dies and your colony will be kilham-free. In breeding colonies the virus survives and may be carried without displaying symptoms until you have a kilham “flare-up”.

BREEDERS CAN CLEAR A COLONY OF KILHAM BY:

• Not breeding any rats for at least 3 months.

• Disinfect cages and accessories with F10 diluted at 8ml per litre.

• Not bring in any new rats into the rattery without a 3 month quarantine. New rats may not be bred during this time.

• Not have ANY contact with other rats or allow other rat owners inside your rattery.

MY OWN EXPERIENCE WITH POSSIBLE KILHAM FLARE-UPS:

CASE STUDY 1:

Two females were mated to the same male. (Ages 6-8 months) Both had trouble conceiving and gave birth to 4 pups each. The male and one female were again mated three months later and produced a normal litter of 12 pups. Pups from all three litters developed normally and produced normal sized litters without fertility issues.

CASE STUDY 2:

Three 8 month old females from the same litter were bred a month apart by three different ratteries. The line has no know fertility issues and usually produce litters averaging 10-14 pups with little to no runting.

My female conceived easily but dramatically lost weight two times during her pregnancy. She eventually gave birth to 7 medium sized pups. She most likely re-absorbed the rest of the litter.

The second female gave birth to 2 live and 5 stillborn pups. (Possible flare-up towards the end of her pregnancy) The third female was left with a male for several weeks but never conceived.

Although Kilhams is not a major issue and holds no thread to pet owners, it is something breeders should be aware of.

#kilham #fertility #breeding