Morphological and morphometric characterization of domestic cat epididymal sperm

Abstract

Sperm morphometry is the tool that confers objectivity to the morphological evaluation by accurately measuring the dimensions of the gamete and its structures. Thus, the aim of the study was to perform a morphometric characterization of the domestic cat sperm. Therefore, sperm samples were collected from twenty pairs of epididymis in a TRIS extender at 37ºC. An aliquot of the sample was used to make a smear with Rose Bengal solution, and afterwards, the morphology and morphometry were analysed. In the morphology, were quantified the percentage of normal sperm cells, morphological changes of head, midpiece and tail. In morphometry, each normal sperm cell was measured for length, width, area and perimeter of head and midpiece, tail length and total length. The parameters ellipticity, elongation, regularity and rugosity were also determined. The percentage of normal sperm was 67.21%. Of the abnormalities, the curled/folded tail, followed by the curved midpiece, abnormal shaped head and detached head were the most quantified. The sperm head presented 5.56 ± 0.01 μm and 3.10 ± 0.01 μm of length and width, respectively. The head area was 16.94 ± 0.05 μm2, while the perimeter was 16.16 ± 0.03 μm. In the derived parameters, the values were as follows: ellipticity of 1.81 ± 0.00; elongation of 21.39 ± 0.12; regularity of 0.81 ± 0.00; and rugosity of 0.14 ± 0.00. The midpiece presented length and width of 7.96 ± 0.01 μm and 0.76 ± 0.01 μm, respectively. The mean length of the sperm tail was 45.12 ± 0.06 μm, and the total cell size was 58.67 ± 0.06 μm. Thus, it was concluded that the cat sperm is an elongated cell, with high rugosity and regularity. The spermatic tail represents more than ¾ of the total length of the cell and the midpiece exceeds the length of the head.

Sperm quality and morphometry characterization of cryopreserved canine sperm in ACP-106c or TRIS

“…A total of 100 sperm were randomly counted under a microscope (1000x) and classified as normal or abnormal. Sperm abnormalities were grouped into changes in the head, midpiece, tail and acrosome (CBRA, 2013;Barbosa et al, 2019).…”

“…Measurements were performed using ImageJ software version 1.4.3.67. Measurements with ImageJ followed the recommendations of published works that used this software for sperm morphometric characterization (Tremori et al, 2014;Barbosa et al, 2019). Measurements were performed by manually clicking on the image, selecting the appropriate software tool for the width and length dimensions (line selection tools), and for area and perimeter (area selection tools).…”

“…Thus, the morphometric analysis is an essential tool for the observation of cryodamages suffered by gametes, since it offers an objective/standardized assessment of conventional morphology (Valverde et al, 2016;Barbosa et al, 2019). Morphometry allows the detection of subtle differences in the size of the sperm head, undetectable to the morphological evaluation, which interferes in the degree of fertility (Paz et al, 2011), the stability of chromatin (Núñez-Martinez et al, 2007a) and the crioresistance of the sperm sample (Ramon et al, 2013).…”

Canine and Feline Epididymal Semen—A Plentiful Source of Gametes

“…Fluid leaving the testis is reabsorbed in efferent duct and caput of the epididymis [7,17] Osmotic pressure within the epididymis increases caudally [17,18] Sperm plasma membrane is composed of large amount of phospholipids, cholesterol and glycoproteins [6,19] Cholesterol stiffens the sperm plasma membrane and increases its permeability [6,7] Glycoproteins coating the plasma membrane change in the same manner during epididymal transit [19] Percentage of spermatozoa with swollen acrosome and incomplete condensed chromatin decreases as sperm migrates distally along the epididymis [3,15] Presence of selective abnormal spermatozoa removal (phagocytosis) [7,17] Retained cytoplasmic droplets will be detached at or post-ejaculation…”

Sperm Quality and Histology of the Testis and Epididymis in Chemical Castrated Male Cats with Intra-testicular Injection of Sodium Chloride Solution

“…The complete testes with epididymis were placed in a sterile plastic container in 0.9% NaCl solution at 37℃ and transported to the laboratory for further analysis. The epididymis was isolated, and sperm was obtained by making an incision in the epididymal duct (de Sousa Barbosa et al, 2019). The sperm was flushed with a five mL saline solution.…”