Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to spot ulcer symptoms in horses [title] Notice any behavioral changes. [step] Symptoms of gastric ulcers can be nonspecific and hard to notice. Your horse may alter their behavior if they have a stomach ulcer.

Ending1: Horses with gastric ulcers are usually not behaved fairly negatively, since change in behavior is often due to negative training. [title] See if the horse is overweight. Ending2: Their attitude may change and they may become less eager to do things they used to. The horse may act irritably or dazed. Ending3: [substeps] Look for any changes in your horse's posture, breathing, etc. Communicate anything you notice to your horse and make sure they're not experiencing any changes. Ending4: This could be due to sensitivity to red blood cells or ulcers that are completely healed. [substeps] Observe your horse for any behavioral changes that may occur.

Answer format: ending1/ending2/ending3/ending4