Tuberculosis in a rabbit: A case revisited

Extract

There has been only one reported case of tuberculosis caused by Mycobacterium bovis in a free-living wild rabbit, Oryctolagus cuniculus cuniculus ⁽¹⁾. Because of continued interest in that case, the common classification of rabbits and hares in the family Leporidae and a current report of a case in a hare⁽²⁾, this opportunity is taken to re-record the case in the rabbit in greater detail.     

Malignant B-cell lymphoma of the Harder's gland in a rabbit

A 22-month-old, female rabbit was presented with a 1-day history of acute unilateral exophthalmos. Ultrasonography and computed tomography (CT) of the orbit revealed an orbital mass. Retrobulbar lymphoma was diagnosed following fine-needle aspiration biopsy (FNAB). Thoracic radiographs were normal, and ultrasonography of the abdomen showed focal hypoechoic thickening of the bowel wall and hypoechoic enlarged lymph nodes. The rabbit was euthanized and histopathology identified the retrobulbar mass as B-cell malignant lymphoma of the Harder's gland. Mesenteric lymph nodes, caecum, and both kidneys were also affected. This is the first documented case of malignant lymphoma of the Harder's gland in a rabbit.     

Spontaneous lymphoma in a Japanese White rabbit

Lymphoma was observed in a 4-month-old female Japanese White rabbit. Grossly, the markedly enlarged mesenteric lymph nodes, prominent Peyer's patches of jejunum, splenomegaly, and enlargement of tracheobronchial lymph nodes, adrenal glands and ovaries were observed. Histologically, neoplastic lymphoid cells proliferated diffusely showing frequent mitotic figures and a characteristic 'starry sky' appearance. Their basophilic cytoplasm contained a few lipid droplets. The mesenteric lymph nodes, Peyer's patches of jejunum, and tracheobronchial lymph nodes were largely replaced by the tumor tissues. The stomach, small intestines, especially the jejunum, liver, spleen, ovaries, and adrenal glands were heavily infiltrated with neoplastic cells. These results suggest that the present lymphoma may have originated from the gastrointestinal lymphoid tissue.     

A case of diffuse bilateral scrotal neurofibroma in a rabbit

This report details a rare case of diffuse bilateral scrotal neurofibroma complicated by hindlimb paralysis in a rabbit. The animal was evaluated for unusual bilateral scrotal enlargement. After physical examination, ultrasound scan, radiography, computed tomography and laparoscopy, surgical exploration of the scrotum was undertaken. A homogeneous rubbery firm mass was revealed in contact with the subcutaneous tissue expanding to the entire scrotum without involving the testicles. The mass was excised and diagnosed as diffuse scrotal neurofibroma based on histological and immunohistochemical findings (S‐100 antibody positive). Over the following month, progressive neurological signs (faecal incontinence, flaccid bladder and hindlimb paralysis) were observed. After excluding central nervous system infection with Encephalitozoon cuniculi, expansion of the neurofibroma to the vertebral canal causing compression of the spinal cord was suspected, although not histopathologically verified.     

Glycohistochemistry of the zona pellucida of developing oocytes in the rabbit and hare

Lagomorpha are often used as animal models in reproductive experiments. The aim of the present study was to examine the glycoconjugate modifications occurring mainly in the zona pellucida during oocyte growth in the rabbit and hare, using a battery of lectins combined with sialidase digestion and chemical treatments. This histochemical approach made it possible to identify sulpho- and asulpho-carbohydrates in the terminal and/or subterminal position linked to sialic acid residues. The lectins that stained the zona pellucida of both species most effectively were SBA, PNA and WGA, indicating the presence of beta-D-N-acetylgalactosamine, beta-D-galactosamine and N-acetylglucosamine residues. The differences in the glucidic residue content and in their spatial distribution that depended on the species and stage of follicle development were also detected.     

A case of combined hermaphroditism and autofertilisation in a domestic rabbit

A true hermaphrodite rabbit served several females and sired more than 250 young of both sexes. In the next breeding season the rabbit, which was housed in isolation, became pregnant and delivered seven healthy young of both sexes. It was kept in isolation and when autopsied was again pregnant and demonstrated two functional ovaries and two infertile testes. A chromosome preparation revealed a diploid number of autosomes and two sex chromosomes of uncertain configuration.     

Microvascular circulation of the cecum in horses

The microvascular circulation of the cecum was studied in 15 adult horses, using microangiography and light microscopy combined with gross studies and scanning electron microscopy of vascular replicas. After heparinization, the horses were euthanatized and the cecum was transected at the cecocolic junction. Blood was flushed free of the circulation with isotonic NaCl and the cecal lumen was slightly distended. In 6 horses, the vascular system was injected with a modified radiopaque medium and evaluated radiographically. Sections evaluated radiographically were also prepared for histologic examination by standard methods. Eight horses were injected with 1 of 2 types of plastics and studied grossly or by scanning electron microscopy. In 1 additional horse, the lateral and medial arteries were injected with different colored plastic for gross studies. The lateral and medial cecal arteries appear to supply the respective areas of the cecum with minimal mixing of the 2 circulations. The major vascular supply to the cecal apex appeared to be through the medial cecal artery. Both the lateral and medial cecal arteries gave rise to cecal retia, which formed a mesh-like network around the respective veins. Vessels from these retia supplied the cecal tissue and the cecal lymph nodes. The continuation of the retia was through long terminal arteries that coursed around the circumference in the submucosa, forming an extensive submucosal plexus. This plexus supplied both the mucosa, and the tunica muscularis and serosa. Vessels within the longitudinal and circular muscle layers of the muscularis externa ran parallel to the muscle fibers, and consequently, perpendicular to each other.(ABSTRACT TRUNCATED AT 250 WORDS)     

一起獭兔囊尾蚴病的诊治报告

本文结合实际病例介绍了獭兔囊虫病的发病情况、临床症状、剖检变化以及实验室检查方法,并提出了有效的治疗措施和预防方法.     

Surgical diseases of the equine cecum

Cecal impaction and cecal perforation, the two most common equine cecal diseases, are thought to develop after slowing or interruption of a single progressive motility pattern, which begins in a pacemaker area near the apex, occurs once every 3 minutes, and propels ingesta from the cecum to the right ventral colon. Rectal examination in horses with cecal impaction is the most useful technique to grade the severity of the condition. Medical treatment is undertaken if the impaction is judged to be mild to moderate. Surgical correction of cecal impaction in severe cases requires a ventral midline celiotomy, and exploration reveals a large ingesta-filled cecum and relatively empty large colon. Currently, the techniques of typhlotomy with manual evacuation of ingesta, combined with a complete bypass of the cecum by use of a jejunocolostomy, is the preferred method of surgical management. The use of a cecocolic anastomosis remains a viable alternative surgical procedure. Cecal perforation (CP), a uniformly fatal disease of horses, most often develops when the subtle signs of cecal impaction are missed or are masked by the administration of nonsteroidal antiinflammatory agents. CP can occur in mares around the time of foaling and, in this form, is not associated with cecal outflow dysfunction. Surgical management of cecocecal or cecocolic intussusception is required and involves resection of the diseased portion of cecum, either with extra- or intraluminal techniques. Both the side-to-side and end-to-side jejunocecal anastomoses are useful and successful techniques for bypass of simple or strangulating lesions of the ileum.     

A case of adenocarcinoma of the endometrium extending into the leiomyoma of the uterus in a rabbit

In a pet rabbit, 2 tumor masses one on each horn were macroscopically seen in the wall of the uterus. On light microscopic examination, the right horn mass consisted of an admixture of neoplastic epithelial and mesenchymal element. The epithelial element was composed of neoplastic epithelial cells with numerous mitotic figures and formed varied sizes of acini, glandular, and solid structures. The tumor was diagnosed as an adenocarcinoma of the endometrium. The mesenchymal element was composed of well-differentiated smooth muscle cells and was diagnosed as a leiomyoma. While adenocarcinoma cells formed a protrusive mass in the uterine lumen, they also showed an extension into the leiomyoma of the myometrium. By immunohistochemistry, adenocarcinoma stained positive for cytokeratin (MNF116) and leiomyoma stained positive for smooth muscle actin, showing a substantial difference in the cytological nature of these tumor cells. The results may give a further evidence supporting the narrative of the tumor development that an adenocarcinoma of the endometrium extended into leiomyoma of the uterus. To the author's knowledge, this is the first report describing this type of combination of two independent tumors in a pet rabbit.     

A case of hemophagocytic syndrome progressing into large granular lymphoma in a dog

A 12‐year‐old castrated male mixed breed dog was presented with anorexia, lethargy, intermittent vomiting, diarrhea, and weight loss. Clinicopathologic and imaging abnormalities included pancytopenia, icterus, and splenomegaly with multiple minute hypoechogenic nodules. Bone marrow (BM) smears revealed 2.5% hemophagocytic macrophages. In addition, an increased number of small to intermediate lymphocytes (16.3%) and plasma cells (3.2%) were recognized in the BM smears. More than 80% of the lymphocytes contained multiple small intracytoplasmic magenta granules. Histopathologic findings of the spleen revealed hemophagocytosis. Large granular lymphocytes (LGLs) were not found on the liver cytology or splenic histopathology at this time. PCR for antigen receptor rearrangement (PARR) analysis showed a clonal reaction in the T‐cell receptor ? (TCR?) gene in the BM sample. The dog was diagnosed with hemophagocytic syndrome (HPS). The dog was maintained in good condition with immunosuppressive therapy. However, the dog developed hepatic LGL lymphoma 7 months later. At this time, PARR analysis showed a clonal TCR? gene rearrangement in the hepatic LGL lymphoma samples. The BM and liver sample clonal rearrangements showed 100% homology, indicating that the small to intermediate granular lymphocytes in the BM at the HPS stage had progressed to hepatic LGL lymphoma. To our knowledge, this is the first report of canine secondary HPS caused by the occurrence of a BM LGL lymphoma clone that progressed to hepatic LGL lymphoma.