Gastric Dilatation-Volvulus in a Guinea Pig (Cavia porcellus)

Morphology of pig nasal structure and modulation of airflow and basic thermal conditioning

Mammals have presumably evolved to adapt to a diverse range of ambient environmental conditions through the optimized heat and mass exchange. One of the crucial biological structures for survivability is the nose, which efficiently transports and thermally preconditions the external air before reaching the internal body. Nasal mucosa and cavity help warm and humidify the inhaled air quickly. Despite its crucial role, the morphological features of mammal noses and their effect in modulating the momentum of the inhaled air, heat transfer dynamics, and particulate trapping remain poorly understood. Tortuosity of the nasal cavity in high-olfactory mammalian species, such as pigs and opossum, facilitates the formation of complex airflow patterns inside the nasal cavity, which leads to the screening of particulates from the inhaled air. We explored basic nasal features in anatomically realistic nasal pathways, including tortuosity, radius of curvature, and gap thickness; they show strong power-law correlations with body weight. Complementary inspection of tortuosity with idealized conduits reveals that this quantity is central in particle capture efficiency. Mechanistic insights into such nuances can serve as a tipping point to transforming nature-based designs into practical applications. In-depth characterization of the fluid-particle interactions in nasal cavities is necessary to uncover nose mechanistic functionalities. It is instrumental in developing new devices and filters in a number of engineering processes.

Liver Lobe Torsion in a Guinea Pig (Cavia porcellus)

A 5-year-old, female intact guinea pig (Cavia porcellus) presented for acute inappetence. The abdomen was severely distended and tympanic with moderate discomfort. Radiographs showed gastric distension and displacement. Gastric dilatation and volvulus were suspected. At necropsy, the left lateral liver lobe was torsed at the hilus and infarcted. Histopathology showed regionally extensive coagulative necrosis and markedly congested sinusoids, causing marked hepatic cord atrophy and dissociation. Final diagnoses were severe gastric dilatation with left lateral liver lobe torsion (LLT) and regionally extensive liver infarction, and hemoabdomen. Reports of LLT in guinea pigs are likely underrepresented in the literature. LLTs should be considered in guinea pigs presenting for acute inappetence and abdominal distension. Laboratory tests and abdominal ultrasound can help differentiate LLT from other gastrointestinal pathologies seen in guinea pigs, such as gastric dilatation and volvulus. Early recognition of LLT in guinea pigs could potentially improve patient outcomes. This is the first published report of LLT in a guinea pig.

Gastric dilatation and enterotoxemia in ten captive felids

CASE DESCRIPTION 10 large felids at 8 facilities were determined or suspected to have developed gastric dilatation with or without enterotoxemia over a 20-year period. Four felids were found dead with no premonitory signs. CLINICAL FINDINGS 4 felids (2 male snow leopards [Uncia uncia], 1 male Amur tiger [Panthera tigris altaica], and 1 male Sumatran tiger [Panthera tigris sumatrae]) were found dead or died before they could be evaluated. Six felids had hematemesis (1 male and 1 female African lion [Panthera leo] and 1 male jaguar [Panthera onca]) or abdominal distention and signs of lethargy with or without vomiting (1 male African lion, 1 male Malayan tiger [Panthera tigris jacksoni], and 1 female Sumatran tiger). Gastric dilatation was radiographically and surgically confirmed in the male Malayan and female Sumatran tigers and the jaguar. TREATMENT AND OUTCOME In 3 felids with an antemortem diagnosis, the gastric dilatation resolved with decompressive laparotomy but then recurred in 1 felid, which subsequently died. Three others died at various points during hospitalization. Although Clostridium perfringens type A was recovered from 3 of the 5 felids for which microbial culture was performed, and 2 felids had a recent increase in the amount fed, no single factor was definitively identified that might have incited or contributed to the gastric dilatation. CLINICAL RELEVANCE Gastric dilatation was a life-threatening condition in the large felids of this report, causing sudden death or clinical signs of hematemesis, abdominal distention, or vomiting. Even with rapid diagnosis and surgical decompression, the prognosis was poor. Research is needed into the factors that contribute to this emergent condition in large felids so that preventive measures might be taken.

Jejuno-jejunal intussusception in a guinea pig (Cavia porcellus)

An approximately four-year-old male castrated guinea pig (Cavia porcellus) was presented for painful defecation with a 24-hour history of hyporexia and intermittent episodes of rolling behavior. Upon presentation the patient was quiet, alert, and responsive, and mildly hypothermic. Abdominal palpation revealed an approximately 2-cm long oblong mass within the caudal abdomen. Abdominal radiographs revealed gastric dilation without volvulus and a peritoneal mass effect. The patient was euthanized following gastric reflux of brown malodorous fluid from his nares and oral cavity. A necropsy was performed and revealed a jejuno-jejunal intussusception causing mechanical gastrointestinal ileus, and gastric dilatation without volvulus. While non-obstructive gastrointestinal stasis is common and obstructive ileus is uncommon in guinea pigs, this report shows that intestinal intussusception is a differential in guinea pigs with ileus and gastric dilatation.

Partial gastrectomy for resection of a gastric leiomyoma in a guinea pig (Cavia porcellus)

CASE DESCRIPTION A 4-year-old sexually intact male pet guinea pig (Cavia porcellus) was evaluated for a routine wellness examination. CLINICAL FINDINGS During physical examination, a small mass was palpated in the cranial aspect of the abdomen. Abdominal radiographic and ultrasonographic findings were suggestive of a gastric mass. Cytologic evaluation of a fine-needle aspirate of the mass was indicative of spindle cell proliferation most consistent with a sarcoma. TREATMENT AND OUTCOME The patient was anesthetized, and an exploratory laparotomy and partial gastrectomy were performed to resect the gastric mass. Histologic and immunohistochemical examinations of the mass revealed that it was a gastric leiomyoma. The patient recovered from surgery without complications. No evidence of mass recurrence was observed during an abdominal ultrasonographic examination performed approximately 19 months after surgery. CLINICAL RELEVANCE To our knowledge, this was the first report of the clinical diagnosis and successful surgical treatment of a gastric neoplasm in a guinea pig. Gastric leiomyomas are not uncommon in guinea pigs, and although benign, they can cause clinical signs if they become large enough to impair gastric function. Gastrointestinal surgery should be considered as a treatment option for guinea pigs with similar gastric neoplasms.

Gastric dilitation-volvulus in a Red Panda (Ailurus fulgens)

A 10-year-old male red panda presented acutely with symptoms of shock due to acute abdominal distress and respiratory compromise. Abdominal ultrasound confirmed a severely distended stomach for which passage of an orogastric tube for relief was unsuccessful. Intra-operatively, the stomach was found to be distended and torsed around its long axis supporting the diagnosis of Gastric dilitation-volvulus (GDV). The animal arrested and died intra-operatively and was submitted for necropsy with lesions supportive of the diagnosis of GDV. No risk factors for GDV were found to correlate between the panda and those described in domestic dogs. This case suggests that red pandas can be susceptible to this condition in captive settings.

Gastrointestinal Disease in Exotic Small Mammals

Exotic small mammal medicine is a relatively new specialty area within veterinary medicine. Ferrets, rabbits, and rodents have long been used as animal models in human medical research investigations, resulting in a body of basic anatomic and physiologic information that can be used by veterinarians treating these species. Unfortunately, there is a paucity of veterinary articles that describe clinical presentation, diagnosis, and treatment options of gastrointestinal (GI) disease as it affects exotic small mammals. Although there is little reference material relating to exotic small mammal GI disease, patients are commonly presented to veterinary hospitals with digestive tract disorders. This article provides the latest information available for GI disease in ferrets (Helicobacter mustelae gastritis, inflammatory bowel disease [IBD], GI lymphoma, systemic coronavirus, coccidiosis, and liver disease), rabbits (GI motility disorders, liver lobe torsion, astrovirus, and coccidiosis), guinea pigs (gastric dilatation volvulus [GDV]), rats (Taenia taeniaeformis), and hamsters (Clostridium difficile). Both noninfectious diseases and emerging infectious diseases are reviewed as well as the most up-to-date diagnostics and treatment options.