Adeniyi T. D, Enaibe B. U, Adekomi D. A and Mohammed O. A
In this study, the superior colliculus (SC) of rat, bat and pangolin were compared using histological and quantitative histochemical parameters to observe possible modification that enable these mammals to cope with their habitation particularly with respect to their diet. The study was conducted using ten adult Wistar rats, ten fruit bats and eight pangolins comprising of both sexes. After being sacrificed by cervical dislocation, their skulls were opened using bone forceps to expose the brains. The superior colliculi were excised from each brain, homogenized and read spectrophotometrically for the activities of lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G-6-PDH), acid phosphatase (ACP) and alkaline phosphatase (ALP). The SC tissue sample meant for histological studies were fixed in 10% formol calcium and processed for paraffin wax embedding. Serial sections of 3μm thickness were stained with Hematoxylin and Eosin and Cresyl fast violet stains. The stained tissues were studied under the light microscope. Application of one-way ANOVA statistical analytical method showed that there were significant differences (p<0.05) in the activities of LDH, G-6-PDH, ACP and ALP of the SC of the three mammals as revealed in the quantitative histochemistry of these enzymes and markers. Histological observations revealed variations in the distribution of neurons and their supporting glial cells with the neurons in the SC of the rat appearing more numerous as well as in the pangolin and are fewer in the bat. The comparison of the differences observed in the histological and the quantitative histochemical activities in these mammalian species revealed a variation in the visual ability and their individual peculiarities in relation to their mode and pattern of living.
