A pig farmers daughter trapped on an island must protect her newborn baby from a bloodthirsty pig born with human hands.

"born with human hands"-- aka: a mutant pig, one modified by genetic engineering with lethal consequences?

Pigs are smart, almost up there with dogs. They're also omnivores. So the concept of a predatory pig (an ironic reversal of the usual relationiship between man and pig) has potential.

Yes, I would say B movie. The log line is pretty well-written but honestly I don't think there would be a market for this :/
Have you already written the script?

This logline gives us, The lead, the leads goal, (and the leads goal of saving her newborn is compelling) It tells us what is standing in the leads way and gives us a sense of genre. all in under 25 words.

Good job.

At this point all the logline needs is very small tweaking and it should be perfect. I would take Kriss Toliday's advice and start with "When" or "After"

Great logline, good luck with this!

Ok...this is rather unusual! Definitely stands out but sounds like a B movie, if that is what you are going for I don't know?

I would perhaps change it to 'When a pig farmer's daughter becomes trapped.....'

Other than that I think the log line works although I'm not sure if it would be something I'd want to see!!