Vets are asking dog owners to keep their dogs on leads when walking near sheep as the annual lambing season gets under way.

The British Veterinary Association called for care to be taken when pets are around ewes as they are particularly vulnerable at this time of year while preparing to give birth.

The body said owners should keep dogs on leads at all times when walking near livestock, but it was particularly important during the spring. Vets have seen a rise in the numbers of attacks. President Robin Hargreaves said: "Tragically this can lead to chasing, attacks and fatalities for sheep and other animals."