Morphological characterization of ejaculated cynomolgus monkey (Macaca fascicularis) sperm

Abstract

The aim of this study was to give reference values for the frequency of morphological sperm abnormalities present in the semen from nonexperimental cynomolgus monkeys as well as for the dimensions of sperm heads. Spermatozoa from the liquid portion of electroejaculates from 14 cynomolgus monkeys were air‐dried as smears, fixed, and stained with Harris's Haematoxylin and subjected to visual analysis of morphology and computer‐aided analysis of ten morphometric variables. The majority (83%) of sperm were morphologically normal. Tail defects were the most common (11%), and showed the highest variation between individuals, the values ranging between 4 and 23%. Head abnormalities consisted of large, tapering, and amorphous forms but were not frequent (0.4%), the values ranging between 0 and 1.3%. Midpiece imperfections were found in all the individuals; the mean percentage was 5%, and the range varied between 3 and 9%. Tail plus midpiece was the only multiple abnormality observed, with a mean value of 1.5% and a range between 0 and 8%. The majority of these double defects consisted of a coiled tail together with a coiled midpiece. Mean values for the morphometric parameters characterizing sperm heads were as follows: area 17.2 μm2, perimeter 15.2 μm, length 5.8 μm, width 4.0 μm, L/W ratio 1.5, gray‐level 98, ellipticity 0.2, first shape factor 0.9, second shape factor 1.4, and third shape factor 1.1. Overall coefficients of variation for the majority of parameters were below 7%, showing the great homogeneity in the dimensions of cynomolgus sperm heads. Most useful parameters for sperm characterization, according to their low variability, were perimeter, length, width, L/W ratio, and shape factors. Differences in these parameters were, however, observed between monkeys. Am. J. Primatol. 47:105–115, 1999. © 1999 Wiley‐Liss, Inc.

Sperm head morphometry in ejaculates of adult marmosets (Callithrix jacchus): A model for studying sperm subpopulations and among-donor variations

“…Despite CVs reported for other primate species (Cynomolgus spp.) with regard to sperm morphometric dimensions [30], after cluster analysis, marmoset ejaculates were less homogeneous than expected. Within-animal results for morphometric parameters were surprisingly variable; this was attributed to the heterogeneity of sperm head populations, with strong evidence of the considerable polymorphism in this primate species.…”

“…Within-animal results for morphometric parameters were surprisingly variable; this was attributed to the heterogeneity of sperm head populations, with strong evidence of the considerable polymorphism in this primate species. In the present study, it was difficult to determine if a specific dimension or shape parameter was the most suitable for using in the identification of individual marmosets, indicating the marked variability of sperm morphometric parameters for individual animals, in opposition with the results reported for cynomolgus monkey [30], where perimeter and shape may be the most important parameters. Unfortunately, the study by Gago et al [30] was carried out with traditional statistical methods, considering the whole ejaculate as a homogeneous sperm population, which may have caused substantial loss of information.…”

“…In the present study, it was difficult to determine if a specific dimension or shape parameter was the most suitable for using in the identification of individual marmosets, indicating the marked variability of sperm morphometric parameters for individual animals, in opposition with the results reported for cynomolgus monkey [30], where perimeter and shape may be the most important parameters. Unfortunately, the study by Gago et al [30] was carried out with traditional statistical methods, considering the whole ejaculate as a homogeneous sperm population, which may have caused substantial loss of information. Thus, the most useful parameters for marmoset sperm characterization, according to their variability, remain undefined, and largely depend on the individual studied and its specific CV.…”

The seminal coagulum favours passage of fast-moving sperm into the uterus in the black-handed spider monkey

“…Following the WHO (1992) guidelines, we assessed the quantity and quality (movement) of sperm as shown in Table 1, since this method also has proven useful in non-human primates (Gago et al 1999). We categorised sperm movement into four types: FLM, SLM, NLM and IMM.…”

Frozen-thawed rhesus sperm retain normal morphology and highly progressive motility but exhibit sharply reduced efficiency in penetrating cervical mucus and hyaluronic acid gel

“…A careful characterization of ejaculated cynomolgus monkey sperm morphology has been conducted previously and has been cited frequently for reference values for macaque sperm dimensions and abnormal forms [35,36]. In our and the Gago et al [35,36] studies, sperm were fixed similarly and stained with haematoxylin which provides optimal contrast and well-defined sperm head boundaries. Our findings with respect to morphology of fresh ejaculated rhesus sperm are very similar to the cynomolgus sperm reference values.…”