Final answer:
Gastrointestinal issues in animals are usually signaled by behaviors such as lethargy and colic, and can be caused by infections or intoxications, leading to symptoms like vomiting, diarrhea, and abdominal discomfort.
Step-by-step explanation:
Behaviors often associated with gastrointestinal issues in animals include lethargy, colic (as seen in horses), or 'choke', which refers to an obstruction of the esophagus. Gastrointestinal diseases can arise from infections or intoxications, leading to a range of symptoms such as diarrhea, vomiting, and abdominal discomfort. For example, gastritis leads to an inflamed stomach lining, while gastroenteritis affects both the stomach and intestinal lining, causing symptoms like nausea and diarrhea. Food intoxication can result in colitis, where the inflamed colon leads to watery stools and possibly dysentery, characterized by bloody or mucus-filled diarrhea. It is important to note that signs such as circling, excessive barking, tail chasing, and excessive sleeping are less indicative of gastrointestinal problems and more often associated with neurological or behavioral issues.