What is a ‘non-viable’ lamb?

Tim Tyne with a healthy lamb

Tim Tyne with a healthy lamb - Credit: Archant

Recently I was reading a write-up that someone had posted on an online forum about their recent lambing experiences. I found it really helpful, but I wasn’t sure what they meant when they said that some ‘non-viable’ lambs had been born. Can you explain this please?

Tim Tyne says:

A non-viable lamb is one that’s born alive, but with zero chance of survival. This usually applies to very low birthweight lambs, associated with prematurity. It’s fairly common to get a few lambs born at the beginning of the season that aren’t viable, but these losses can be kept to a minimum by having an appropriate flock vaccination program in place against abortion (e.g., toxoplasmosis), and by ensuring that all handling of pregnant ewes is extremely sympathetic. It’s also important not to write off all unusually small lambs as ‘non-viable’ when in fact, with due care, some may survive. The little chap in the photo weighed barely a kilo at birth (to put that into context, the average birthweight of our lambs is between 3.5 and 4.5 kg) but is well and thriving.