Sperm Morphology in the Domestic Cat, and its Relation with Fertility: A Retrospective Study

Abstract

Knowledge about normal ranges in semen quality and the association between sperm morphology and fertility in felids is limited. The aims of this retrospective study were to (1) define a normal spermiogram in cats; (2) evaluate possible effects of season, age and breed on sperm morphology; and (3) evaluate the relationship between sperm morphology and fertility. Semen samples collected by electroejaculation from 52 cats were evaluated for sperm morphology. The cats constituted two groups: a general population of cats (n = 48) and cats examined because of poor breeding records (n = 4). The general population was divided into household (n = 20), pedigree (n = 19) and colony cats (n = 9) and into three age classes, <12 months, 12-59 months and >or=60 months. The median percentage of normal spermatozoa in the general population was 44.0% (range 1.0-91.0%). Criteria were tentatively set for what was considered a normal spermiogram. The mean percentage of normal spermatozoa was higher during February to July than during August to January (p < 0.05). Pedigree cats had a lower mean percentage of normal spermatozoa than did household cats (p < 0.05). Age had no effect on the percentage of normal spermatozoa but was positively correlated with the percentage of proximal droplets. Of the cats with <40% normal spermatozoa (n = 19), all those with known breeding records (n = 11) had produced litters. The four cats examined because of poor breeding results had higher percentages of different sperm abnormalities than tentatively stipulated for the normal spermiogram. In two of these cats both sperm morphology and fertility changed over time.

A comparison of quality parameters of fresh feline ejaculates collected by three different collection techniques

“…To the best of our knowledge, the current study is the first to compare quality parameters of fresh sperm obtained by three different methods of sperm collection from the same male cats-urethral catheterization after medetomidine administration, electroejaculation and epididymal slicing after orchiectomy. The results obtained in our study confirm that good-quality ejaculates can be collected by EE and EP (Axnér & Linde-Forsberg, 2007;Filliers et al, 2010;Johnston et al, 2001;Lengwinat & Blottner, 1994;Zambelli & Marco, 2006). The evaluation of quality parameters of sperm from these two methods indicated similar results.…”

Normozoospermic versus teratozoospermic domestic cats: differential testicular volume, sperm morphometry, and subpopulation structure during epididymal maturation

“…Although this combination has proven to be efficient, objective and useful for the evaluation of sperm subpopulations in several species, there are no reports that describe the subpopulational characteristics of feline sperm as determined by a CASA-Morph system. Our hypothesis was that teratozoospermia is reflected in different stages of sperm maturation in the epididymal duct and would produce alterations in the sperm morphometric subpopulations that would explain the reduced fertility potential 26. In general, our results indicated that spermatozoa from different epididymal regions such as R1 or R2 could be used as predictors of teratozoospermia in domestic cats because of the morphometric differences reported in the present study between N and T groups.…”

“…Our data demonstrated significant differences in sperm morphometric values in different epididymal regions and between donor groups. Marked differences have been found in sperm morphometric subpopulations among epididymal regions and N and T donor groups, and this fact might be associated with fertility, since an unequivocal influence of sperm morphology on feline sperm fertilizing potential has been demonstrated 26. To our knowledge, this is the first research that has documented relevant findings related to testicular morphometry and sperm subpopulations differences during sperm migration through the epididymal duct in both normozoospermic and teratozoospermic domestic cats.…”

Influence of age, nutritional status and season on the reproductive system in wild male mink (Neovison vison)

“…The frequency of all sperm defects was generally low. Comparing the data with domestic carnivores, the majority of the mink would probably have been fertile, although three mink had sperm defects that might impair fertility to some extent (Axnér and Linde Forsberg 2007); one with 40% loose heads, one with 18% pathological heads and one with 20% mid-piece defects. One mink was sterile as it had sperm which all lacked tail.…”