Standing alone in the field, twitching their tail uncomfortably – this is a common sign of ailment in cows or heifers during the summer months. On further inspection, a reddened muzzle and swelling around the head and back end can sometimes be seen. When brought in, they may move slowly and seem like they are in pain. These heifers can often appear lame or like they are walking on hot coals. These are just some of the signs that may alert you to a condition often seen in the summer months called photosensitisation. In severe cases, the condition can sometimes be seen on cow’s skin. With a few reported and suspected cases over the last 10 days, we look at this disease’s symptoms, treatments and options for prevention.

What is happening?