Monday, February 3, 2014

Guinea pig pregnancy

This is a conscious dorso-ventral radiograph of a guinea pig sow, heavily pregnant with two foetuses. To the untrained eye, radiographs or x-rays can be challenging to interpret. So I've labelled the foetal skulls in the image below - you can even spot their little incisors.
A is the most easily visible skull, from which you can trace the spine coursing toward the right of the image. B marks the other foetus - again fully calficied, with the spine coursing to the left of the picture. Guinea pig skeletons are visible on radiographs from about 6 weeks into gestation.
This pregnancy is entirely my fault (well, there were other key players as one might imagine). When my boar Radike Samo passed away I needed a companion for his cohabitant and lifelong friend, Randy, who fretted so much he stopped eating. I made some contacts and found someone with a young boar JUST THE RIGHT AGE. However, I was in a hurry. I had double parked. I took this well meaning person's word for it, raced home, introduced the new boar to Randy and then looked downstairs. The "boar" had female genitalia. Or, in the words of Paul Anka, performed by Tom Jones: "She's a lady...whoa whoa whoa she's a lay-deh!..."

As one well-worn guinea pig website attests, guinea pigs don't change sex spontaneously. They are mis-sexed. Which admittedly is easily done. (The best resource on sexing GPs is here). Palpating for a guinea pig penis is a task best not attempted when one is double parked in peak hour with the thought of a boar at home fretting to death. Nor should it be left to anyone selling you a guinea pig for cashola. At the end of the day, if you ask for a boy, they're gonna give you a boy, right? 

Despite his name, Randy showed little interest. I considered desexing him but as he is quite old the anaesthetic risk was not insigificant. And speying female guinea pigs brings its own risks. So pregnancy was inevitable.

This week, Cornflake - a very flighty, petite lady, has been waddling around looking like she swallowed a discus. Since there is no sort of pee-on-a-stick equivalent for animals, I decided to take a radiograph.

(My tip for taking conscious radiographs of a guinea pig - just pop them in a nice small cardboard box for a moment and they tend to sit still for the few seconds it takes).

Flash, a former guinea pig of mine, demonstrates the box technique for radiographing guinea pigs. This position is very helpful for ruling out nephroliths, uroliths and for counting foetuses in gravid sows.

Cornflake is a very flighty lady and not keen on being handled, so I've kept that down to a minimum. Gestation is supposed to range from 59-72 days depending on the size of the litter (larger litters are usually born earlier in the piece).

There are plenty of complications that can occur including pregnancy toxaemia, foetal resorption, premature birth, uterine haemorrhage, dystocia, stillbirth, uterine or vaginal prolapse, post-partum haemorrhage, mis-mothering, mastitis, agalactia and eclampsia to name but a few. Even well-meaning guinea pig mums can maul their bubs if they try to pull them out when they get stuck.

So its something of a nail-biting time here at SAT headquarters. Thankfully we're all stocked on orchard grass and vegies. Exciting times!