Rotavirus

Etiology:  Rotavirus is an RNA virus of the family Reoviridae.  This virus contributes to rabbit diarrheal syndromes.

Incidence:  Rare in laboratory rabbits.

Transmission:  Rotavirus is spread by fecal-oral transmission.  Naïve rabbits of all ages, breeds, and sexes develop a similar disease course.  In endemically infected colonies, infection occurs in 4 to 7 wk-old rabbits.

Clinical Signs:   Clinical signs may be mild or severe, especially if complicated by concurrent enteric pathogens.  Rabbits may have diarrhea, which may range from soft to watery.  Lethargy, anorexia, and dehydration may accompany diarrhea.  Morbidity and mortality are generally low but increase when the disease is complicated by other diseases.

Pathology:  Grossly, the cecum is fluid-filled, and enlarged mesenteric lymph nodes are visible.  Histologically, vacuolation and desquamation of apical enterocytes with villous fusion and atrophy primarily in the jejunum and ileum are visible, with edema in the mucosa and submucosa.  The lamina propria is infiltrated with lymphocytes and occasional neutrophils. There may be focal mucosal erosions in the cecum.

Diagnosis:  Virus can be detected using serologic tests MFI or IFA or RT-PCR amplification of feces.  Identification of histologic lesions in intestinal tract may be used to confirm diagnosis.