doi:10.5455/vetworld.2013.360-362 Ectopic spleen in the pancreas of New Zealand White rabbits

Five cases (male-2, female-3) of ectopic splenic tissue in the pancreas of New Zealand White rabbits were recorded out of 144 rabbits aged between 16-25 weeks. The histomorphology of the ectopic splenic tissue compared well with normal spleen. The pancreatic parenchyma bearing ectopic splenic tissue did not exhibit any change or abnormality of pathological significance except less number of islets of Langerhans in comparison to other areas. The present cases were considered to be rare incidental finding and congenital in origin.


Introduction
Experiments on Animals (CPCSEA), India.All rabbits were procured from CPCSEA approved breeding Ectopia is a rare congenital anomaly where a facility and were housed individually in stainless steel small mass of any histologically normal tissue is 0 cages in air conditioned rooms at 20±3 C and relative present at abnormal site e.g.parathyroid within thymus humidity of 30 to 70%, with 12 h artificial light and 12 or pancreatic tissue in duodenum, liver and spleen [1, h dark.The air changes in the experimental rooms were 2].It is incidentally recorded only during histopathominimum 15 per hour.Standard food pellets and clean logical interpretation among laboratory animals filtered water were provided to the rabbits ad libitum subjected to preclinical toxicological studies and other throughout the duration of experiment.biological experiments [3].Among human beings, These animals appeared normal without any intrapancreatic ectopic/accessory spleen is recorded clinical expression during life-phase part of the study.during ultrasonography carried out in the diagnosis of On termination of the life-phase of the study, these various abdominal ailments or unselected autopsies animals were received at Pathology section for routine [4,5].There is paucity of information on various post mortem examination.ectopic tissues in the pancreas of different laboratory The animals were euthanized by carbon dioxide animals.Five cases of ectopic splenic tissue in the asphyxiation prior to conducting routine necropsy.pancreas of young New Zealand White rabbits of either External as well as internal examination of the carcasses sex encountered during routine histopathological did not reveal any abnormality of pathological signifiobservations excited us to put these cases on record.
cance.Grossly, the pancreas which is of mesenteric

Materials and Methods
type (diffusely distributed in the mesentery of small bowel) in rabbits, appeared normal.All the required One hundred and forty four (male -72, femaleorgans including pancreas as per the study protocol 72) New Zealand White rabbits aged between 16-25 were collected and preserved in 10% neutral buffered weeks from various repeated dose toxicity studies formalin for fixation.The fixed morbid tissues were conducted in compliance with the OECD (Organiprocessed routinely to have H & E stained microsections zation for Economic Cooperation and Development) (5 µ thick) for histopathological evaluation.Principles of Good Laboratory Practice at Jai Research Foundation, Vapi (Gujarat) formed the materials for

Results
this study.Project proposals for these studies were duly Out of 144 rabbits examined, ectopic splenic approved by Institutional Animal Ethics Committee tissue was microscopically recorded in pancreas of five (IAEC), Jai Research Foundation and these studies animals (males-2, females-3) showing occurrence rate were undertaken in compliance with the 'Guidelines for of 3.47%.In four cases, the ectopic splenic tissue was Laboratory Animals Facility' issued by the Committee devoid of any fibrous capsule and was closely for the Purpose of Control and Supervision of embedded in the pancreatic parenchyma (Fig. 1, 2).In fifth one, the splenic tissue was loosely attached to pancreatic margin, surrounded by a thin delicate capsule (Fig. 3, 4) and was comparable to previous observation [3].The ectopic splenic tissue did not centimeters, either single or multiple in numbers [5,7, reveal any notable change and appeared normal 8,9].Thus, the rate of occurrence of intrapancreatic maintaining its usual histological architecture i.e. red ectopic splenic tissue was quite high in comparison to pulp, white pulp (periarteriolar lymphoid sheath -our report.Analysis of several inbred strains of rabbits PALS), marginal zone and a few scattered fibrous with high (30-50%) frequencies of accessory spleens trabeculae.Further, evidence of any compression at the revealed that hereditary haematological diseases, junction of pancreatic -splenic tissues could not be autoimmune haemolytic anaemia and lymphosarcoma observed in any case.Microscopically, the pancreas were associated with some of these conditions [10].also appeared normal with scattered islets of Del Chiaro et al. [4] and Schreiner et al. [11] opined Langerhans which consisted of closely apposed that ectopic intrapancreatic splenic tissues are usually branching cords of pale staining polygonal cells detected incidentally as hypervascular solid nodules surrounded by basal lamina.However, the part of and might be misdiagnosed as neuroendocrine pancreatic parenchyma having ectopic splenic mass tumours.In the present study, the pancreas grossly contained less number of islets in comparison to other appeared normal in all the five cases.These cases were areas, the reason of which was uncertain.
considered incidental in nature and congenital in origin supporting the views of earlier workers [3,6].