A calf is a young cow. A young female cow, especially one that has not yet had a calf, is called a heifer: H-E-I-F-E-R.
VOA: special.2009.07.21
The jinx appears to follow his every journey: "Train manager on Tannoy: "To those with reservations for coaches F, G, H, I and J, as you can see, they're not attached to this train.