Acute necrotizing colitis with pneumatosis intestinalis in an Amazonian manatee calf

Abstract

On 25 January 2014, a 1 mo old female Amazonian manatee Trichechus inunguis calf weighing 12 kg was rescued by air transport in Guajará, Brazil, and transferred to Mamirauá Institute's Community-based Amazonian Manatee Rehabilitation Center. The calf presented piercing/ cutting lesions on the back, neck, and head, in addition to dehydration and intermittent involuntary buoyancy. X-ray analysis revealed a large amount of gases in the gastrointestinal tract. Daily procedures included wound cleaning and dressing, clinical and laboratory monitoring, treatment for intestinal tympanism, and artificial feeding. Adaptation to the nursing formula included 2 kinds of whole milk. Up to 20 d post-rescue the calf presented appetite, was active, and gained weight progressively. Past this period the calf started losing weight and presented constant involuntary buoyancy and died after 41 d in rehabilitation. The major findings at necropsy were pneumatosis intestinalis in cecum and colon, pulmonary edema, and hepatomegaly. The microscopic examination revealed pyogranulomatous and necrohemohrragic colitis with multinucleated giant cells, acute multifocal lymphadenitis with lymphoid depletion in cortical and paramedullary re gions of mesenteric lymph nodes, and diffuse severe acinar atrophy of the pancreas. Anaerobic cultures of fragments of cecum and colon revealed colonies genotyped as Clostridium perfringens type A. We speculate that compromised immunity, thermoregulatory failure, and intolerance to artificial diet may have been contributing factors to the infection, leading to enterotoxemia and death.

Advances in the knowledge of the biology and conservation of the Amazonian manatee (Trichechus inunguis)

“…They may include diarrhea, constipation, cramping, hyporexia, restless swimming, tenesmus, and signs of dehydration (Lazzarini et al, 2014;Davis & Walsh, 2018). Guerra-Neto et al (2016) reported the first case of necrotizing enterocolitis with pneumatosis intestinalis in an Amazonian manatee calf. Many rescued calves arrive in poor body condition, underweight and frequently hypoglycemic and dehydrated (Davis & Walsh, 2018).…”

Infectious and Non-Infectious Diseases in Manatees in Brazil

“…No encalhe, muitos filhotes costumam ser resgatados com grau de desidratação elevado, estado nutricional ruim, diarreias e constipações [64]. A etiologia destas doenças podem ser contaminação de alimentos, falta de adaptação da dieta alimentar, processos infecciosos, entre inúmeras outras causas [7,23,35,63]. Casos já descritos acima, como de identificação de Salmonella sp., rotavírus e Cryptoporidum sp., podem ocorrer por alimentos ou água contaminadas por estes agentes.…”

“…O timpanismo intestinal foi relatado em filhote de T. inunguis evoluindo ao óbito do peixe-boi. Nos achados de necropsia foi verificado hepatomegalia, pneumatose intestinal no ceco e cólon, necroses multifocais e hemorrágicas, confirmados microscopicamente com colite piogranulomatosa e necrohemorrágica com células gigantes multinucleadas [35]. De acordo com o autor, a possível etiologia da doença foi uma intolerância à dieta artificial, causando uma infecção secundária e, consequentemente, a enterotoxemia resultou na morte do filhote.…”