1 - Alimentary system

Abstract

This chapter discusses the diseases associated with the alimentary system of the veterinary animal. Examination of the oral cavity is a standard procedure during any postmortem examination. Lesions in oral cavity may be associated with (1) congenital anomalies such as infectious and inflammatory diseases of teeth and periodontium; (2) trauma, physical and chemical; (3) bacterial, mycotic, viral, and parasitic infections; (4) metabolic and toxic diseases; and (5) immune-mediated, dysplastic, or neoplastic disease such as oral papillomatosis, tumors of dental tissues, and squamous cell carcinomas. The most common conditions of the salivary glands are functional, ptyalism being an increased secretion of saliva and aptyalism. Diseases associated with esophagus discussed in this chapter include epithelial metaplasia, esophagitis, esophageal obstruction, stenosis, and dysphagia. Examination of ruminal contents may provide critical cues with respect to general diseases such as rumenitis and acidosis caused by carbohydrate overload, parasitic diseases of the forestomachs, and neoplasia of the esophagus. The stomach should be carefully examined in animals of any species with a history of inappetence or anorexia, cachexia, hypoproteinemia, diarrhea, regurgitation, or vomition as they could be suffering from gastritis and gastroduodenal ulceration. Further, pathophysiology of enteric disease (malassimilation and diarrhea), congenital anomalies of the intestine, intestinal obstruction (stenosis and obturation), displacements of the intestines (eventration, internal hernia, and external hernia), intestinal ischemia and infarction (venous infarction, arterial thromboembolism, and reduced perfusion) are discussed. Neoplastic and proliferative lesions of the stomach and intestine discussed in chapter include gastrointestinal adenocarcinomas, adenomatous hyperplasia/papillary adenoma/polyps, and gastrointestinal neuroendocrine carcinomas. Approaches to the diagnosis of gastrointestinal disease are also presented. Further, infectious and parasitic diseases of the alimentary tract such as viral diseases of the alimentary tract, bacterial diseases of the alimentary tract, and mycotic diseases of the gastrointestinal tract infections are discussed in the chapter. The anomalies and infection of peritoneum and retroperitoneum are also described.