Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to treat respiratory problems in bulldogs [title] Keep an eye on your dog's breathing. [step] If you have a bulldog you should always be on the look out for signs of breathing distress. If you notice labored breathing early, it can help your dog avoid the discomfort of severe breathing difficulty.

Ending1: [substeps] Have your dog tell you if it's okay when it breathes in or out. If it doesn't, stop immediately and call emergency services. Ending2: The following are signs of respiratory distress : [substeps] Rapid breathing racing or panting inhalations or wheezing shallow breathing changes in the stomach temperature of the tank [title] Know your dog's environmental causes. [step] For the sake of your bulldog's well being, you should make sure you learn their environmental causes. Ending3: If breathing is relaxed, a bulldog may seem calm. Keep an eye out for : [substeps] Labored breathing: these are signs that your bulldog has difficulty breathing and is struggling to breathe. Ending4: [substeps] If you are walking your dog, continually assess how the dog is breathing and if it is having difficulty. Signs of breathing difficulty include excessive wheezing, panting, and, in extreme cases, passing out.

Answer format: ending1/ending2/ending3/ending4