Although you may not be hurting their babies, the mothers do not understand why you are touching them. Some mothers will snort, kick, or run at you as a defense measure to protect their young. Animals sometime give other warning signs when they are upset or hurt. When an animal is showing any of these signs you should not go near them. Fences keep livestock in a restricted area and are there for your protection.
Fences are different for the types of animals they contain.
They are made from a variety of materials. Some fences are electric and may shock you. Some have sharp barbs, and others are wooden or woven wire. Never enter a fence or a pen without adult supervision. You should never tease livestock.