Evaluating the Effect of Chloroform Inhalation as a Method of Euthanasia on the Cerebellum and Hippocampus of Adult Wistar Rats
Ugochukwu Samuel Aguwa *
Anatomy Department, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria.
Okeke Somadina Nnamdi
Anatomy Department, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria.
Ezejindu Darmian Nnabuihe
Anatomy Department, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria.
Eze Chinyere Elizabeth
Anatomy Department, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria.
Azurunwa Ogechi
Anatomy Department, Faculty of Basic Medical Sciences, Madonna University Nigeria, Nigeria.
Obinwa Benedict Nzube
Anatomy Department, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria.
Ovie Ogbo. Felix
Anatomy Department, Faculty of Basic Medical Sciences, Madonna University Nigeria, Nigeria.
Obi Kelvin Chukwuemeka
Anatomy Department, Faculty of Basic Medical Sciences, University of Abuja, Nigeria.
Onwuelingo Sopuru
Anatomy Department, Faculty of Basic Medical Sciences, Madonna University Nigeria, Nigeria.
Okonkwo David
Anatomy Department, Faculty of Basic Medical Sciences, Madonna University Nigeria, Nigeria.
Doris Ogbuokiri
Anatomy Department, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria.
Okeke Chijioke
Anatomy Department, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Chloroform inhalation is a common method of rodent euthanasia in Nigeria for research purposes. This work is designed to evaluate the consequence of this method of sacrifice on the cerebellum and hippocampus of Wistar rats. Twenty male Wistar rats weighing between 160 and 180 were divided into 4 groups of 5 rats each. Group A served as control and was sacrificed using cervical dislocation (a widely acceptable non-inhalation method of sacrifice). Groups B, C and D were exposed to chloroform for 5 minutes once a day (group B), once a day for 2 days and once a day for 3 days. The brains were removed; four from each group was processed for antioxidant assay while one from each group was fixed in Bouin’s fluid for histological studies. Our results show that chloroform inhalation adversely affected the results of the antioxidant parameters studied in a dose-dependent fashion. That means that the adverse effect worsened as the number of days increased. This was also the case with the histology results as there was evidence of cell necrosis in the cerebellar and hippocampal tissues. This also showed dose dependence. We therefore conclude from our results that when studying the brain tissues or carrying out brain related researches, chloroform inhalation is not the method of choice for rat euthanasia.
Keywords: Euthanasia, chloroform, inhalation, cerebellum, hippocampus