Spermatozoa morphometry and ultrastructure in estuarine crocodile (Crocodylus porosus)

摘要

Objective: To evaluate normal spermatozoa morphometry and ultrastructure in estuarine crocodile (Crocodylus porosus). Methods: Four adult male crocodiles aged between 12-15 years, with an average snout to tail length of (3.15±0.01) m were selected for this study. Manipulation of the phallus digitally from the base of the penis was performed on four adult male crocodiles to facilitate the flow of semen to the sulcus. Semen was collected from all individuals for spermatozoa morphometry and ultrastructure study. Morphometry analysis was performed from eosin-nigrosin stained spermatozoa sample. Scanning electron microscopy was conducted to observe the surface ultrastructure of spermatozoa. Results: The morphology of crocodile spermatozoa was made up of acrosome, head, and tail which corresponded to (5.55±1.20) μm, (12.74±1.57) μm, and (70.67±4.40) μm, respectively. The total length of spermatozoa in estuarine crocodile was measured at (88.96±0.52) μm. The most common spermatozoa abnormalities found in the samples were cytoplasmic droplets. Conclusions: Normal morphology, morphometry of spermatozoa in estuarine crocodile which are vermiform shaped-head with a long tail along with questionably high cytoplasmic droplets count are described in this study.