Acute Gastric Dilatation in Nonhuman Primates: Review and Case Studies

Abstract

Abstract. Acute gastric dilatation occurs sporadically in laboratory-housed nonhuman primates. Clinical histories often include chronic drug administration, food restriction, accidental overfeeding, and prior anesthesia. Monkeys may be found dead or may have clinical signs of colic, abdominal distention, and dyspnea. Death in untreated cases is due to impaired venous return and cardiopulmonary failure. Gastric distention with fermented gaseous ingesta and congestion of the abdominal viscera are the predominant lesions. The cause of acute gastric dilatation is unknown, but it probably is multifactorial. Two principal factors seem to be intragastric fermentation associated with Clostridium perfringens, and abnormal gastric function.Acute gastric dilatation occurs sporadically in laboratory-housed nonhuman primates and there is a high mortality rate in untreated cases. The cause of this condition has not been investigated in controlled laboratory studies, but the clinical syndrome and the lesions are well characterized [2,7,11,[13][14][15][16]. In this paper, reported cases of acute gastric dilatation in nonhuman primates are reviewed and compared to the condition in 2 1 monkeys necropsied at a university medical facility.Acute gastric dilatation was first reported in eight macaques in 1967 [2]. Subsequently, there have been cases in both Old and New World monkeys [4,7,9,11,[13][14][15][16]. The clinical syndrome and lesions of acute gastric dilatation are remarkably consistent in all reports, including ours (see Results). The pathogenesis of acute gastric dilatation has not been elucidated, but there seem to be several common predisposing factors: dietary manipulation, microbial fermentation of ingesta, and prior anesthesia. Intercurrent disease rarely is present, although there was one report of acute gastric dilatation in a pet Ateles geoffroyi that also had rickets [7].The quantity and composition of monkeys' diets are important in the pathogenesis of acute gastric dilatation. Many monkeys with a history of food restriction in conjunction with behavioral experiments develop the syndrome following subsequent ad libitum feeding or overfeeding 111, 14, 151. Changes in feeding practice over 126

Considerations in the Selection and Conditioning of Old World Monkeys for Laboratory Research: Animals from Domestic Sources

“…Thus, there may be animal selection issues associated with experimentally manipulated changes in diet. Care must also be taken to prevent animals from overeating following a period of food restriction, as gastric dilation may result (Pond et al 1982). Finally, longterm controlled caloric restriction was shown to have beneficial effects on morbidity, insulin sensitivity, and mortality in rhesus monkeys (Bodkin et al 2003).…”

Changes in Food Intake and Abnormal Behavior Using a Puzzle Feeder in Newly Acquired Sub-Adult Rhesus Monkeys (Macaca mulatta): A Short Term Study

“…However, we found an increase in the consumption time in the puzzle feeder condition that was probably due to the novelty of the puzzle feeder. It has previously been reported that some monkeys are in danger of serious problems, such as acute gastric dilatation (AGD), due to food restriction or accidental over feeding [12], as well as altered feeding schedules [3,10]. To the author's knowledge, many monkeys that are housed individually at laboratory facilities die because of AGD regardless of the experiment.…”

Acute gastric dilatation after porcine islet transplantation in a cynomolgus monkey – case history and review of the literature

“…In macaques, AGD was first reported in 1967 [11]. In his clinico-pathological studies of gastrointestinal diseases in macaques, conducted over a 2-yr period with 335 animals, Holmberg [1] reported that AGD represented 12% (7 of 57) of the deaths from enteric disease and 2% (7 of 335) of the total deaths evaluated.…”