Histomorphometry of the Testes, Epididymides, and Spermatozoa of Four Indigenous Breeds of Bulls in Ibadan, Nigeria

Abstract

Forty testicles were used to carry out histomorphometry study on the testes, epididymides and spermatozoa of four indigenous breeds of bull found in Ibadan (Red Bororo (RB), Sokoto Gudali (SG), White Fulani (WF) and Dhali (DL)). The testicles were harvested immediately after the slaughter at the Bodija abattoir and transported to the laboratory in an insulated flask containing warm water at 37?C within 30 minutes. In the laboratory, the samples were dissected and histological sections of the right testis, right and left caudal epididymides taken from two bulls in each group. The tissues were fixed in Bouin’s fluid. They were processed in an automatic tissue processor, embedded in paraffin wax using the embedding system (Leica EG 1160) and sectioned with microtome at 4 microns. The sections were then stained by Haematoxylin and Eosin method and mounted and examined under a microscope. There was no significant difference between breed and seminiferous tubular diameter (STD) and testicular germinal height (TGEH). The mean STD ranged from 223.00 ± 28.35 to 316.00 ± 37.70 μm, while the TGEH ranged from 81.60 ± 10.05 to 89.80 ± 4.83 μm. The mean epididymal tubular diameters (ETD) and epididymal lumen diameters (ELD) had the highest value of 378.00 ± 10.95 and 298.20 ± 26.0489 μm in DL and lowest of 373.80 ± 37.70 and 278.10 ± 27.71 μm in RB, respectively. The mean epididymal germinal epithelia heights (EGEH) were highest (61.20 ± 5.70 μm) in WF and lowest (39.80 ± 0.86 μm) in RB. The mean sperm head length (SHL), sperm midpiece length (SMPL), sperm tail length (STL) and sperm total length (TL) had the highest values of 5.90 ± 0.10, 8.80 ± 0.25, 24.20 ± 2.59 and 38.90 ± 2.94 μm, respectively in SG. SHL and SMPL were lowest in DL bulls (5.00 ± 0.00 and 6.30 ± 0.20 μm), while STL and TL were lowest (18.90 ± 0.24 and 31.30 ± 0.85 μm). The results of this study provide baseline data on the histomorphometry of the testes and epididymides and spermatozoa of some indigenous bulls.