title: Caecum location in laboratory rats and mice: an anatomical and radiological study.
abstract: Intraperitoneal (i.p.) injection is the most frequently used method for implementing parenteral therapies in rats and mice. Whether the caecum is located in the right caudal quadrant or left caudal quadrant in the abdominal cavity is not clear. For that reason, we have developed a method for identifying the location of the caecum in rats and mice and thus revealed the most reliable location for i.p. injection in these animals. Two hundred Wistar albino rats and 100 BALB/c mice were used. The location of the caecum was determined by revealing the intra-abdominal organs immediately following euthanasia, photographing the organs, and archiving the images. Both digital photographic images and computed tomographic (CT) sections were analysed in terms of caecum morphology and location. In both rats and mice, the caecum was most commonly located on the animal's left side. It was less frequently located on the right side or in the centre. The caecum was typically comma-shaped, but it was round or S-shaped in some animals. The direction of rotation of the caecum from the basis to the apex was mostly counterclockwise. Additionally, the apex showed a tendency to be evenly centred. This study demonstrated that the caecum was mostly located on the animal's left side; and for that reason, the most suitable location for i.p. injection in these animals was understood to be the right caudal quadrant. Furthermore, when we compared the CT images and autopsy findings, the caecum did not change location in the abdominal cavity postmortem.
authors.affiliation: 1 Department of Anatomy, Faculty of Medicine, Gaziosmanpasa University, Tokat, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Uysal
authors.affiliation: 2 Department of Nuclear Medicine, Faculty of Medicine, Gaziosmanpasa University, Tokat, Turkey.
authors.forename: Serdar Savaş
authors.initials: SS
authors.lastname: Gül
authors.affiliation: 3 Department of Emergency Medicine, Tokat State Hospital, Tokat, Turkey.
authors.forename: Serhat
authors.initials: S
authors.lastname: Karaman
authors.affiliation: 1 Department of Anatomy, Faculty of Medicine, Gaziosmanpasa University, Tokat, Turkey.
authors.forename: Ufuk
authors.initials: U
authors.lastname: Tas
authors.affiliation: 1 Department of Anatomy, Faculty of Medicine, Gaziosmanpasa University, Tokat, Turkey.
authors.forename: Hilal Irmak
authors.initials: HI
authors.lastname: Sapmaz
authors.affiliation: 4 Department of Physiology, Faculty of Medicine, Uludag University, Bursa, Turkey.
authors.forename: Funda
authors.initials: F
authors.lastname: Uysal
authors.affiliation: 5 Department of Orthopedics and Traumatology, Faculty of Medicine, Giresun University, Giresun, Turkey.
authors.forename: Kursad
authors.initials: K
authors.lastname: Aytekin
authors.affiliation: 6 Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Gaziosmanpasa University, Tokat, Turkey.
authors.forename: Mehmet Kemal
authors.initials: MK
authors.lastname: Tümer
mesh_terms: D000818:Animals; D002432:Cecum / Q000033:anatomy & histology*; D007274:Injections, Intraperitoneal / Q000379:methods / Q000662:veterinary; D051379:Mice / Q000033:anatomy & histology*; D051381:Rats / Q000033:anatomy & histology*; D017208:Rats, Wistar
keywords: caecum; localization; mice; morphology; rat