Comparison of endoscopic-assisted transcervical and laparotomy insemination with frozen-thawed dog semen: A retrospective clinical study

The aim of this study was to develop and validate a novel, computer‐assisted spermatozoal quantification (CASQ) method of determining spermatozoal concentration in canine semen. In Experiment A, the spermatozoal concentration was measured (n = 28) with a haemocytometer using light microscopy, CASQ and computer‐assisted semen analysis (CASA; MMC sperm), following three independent dilutions. The limits of agreement between the haemocytometer and CASQ were −13.1% to 13.8% and −27.0% to 28.6% between the haemocytometer and CASA. The precision CVs (limits of agreement) were 5.7% (−7.8% to 8.9%) for the haemocytometer, 6.2% (−8.8% to 12.3%) for CASQ and 10.8% (−16.0% to 19.5%) for CASA. In Experiment B, spermatozoa were manually counted (n = 42) with the haemocytometer under fluorescent illumination using the CASQ sample. The limits of agreement between the CASQ and the haemocytometer were satisfactory (−4.6% to 4.6%) and the precision CVs (limits of agreement) were 6.2% (−9.0% to 11.4%) for the haemocytometer and 4.4% (−5.8% to 8.6%) for CASQ. The CASQ method was then clinically applied to compare the haemocytometer (light and fluorescent methods) with CASQ and CASA. Outlying data were removed. These studies demonstrated that CASQ was reliable and that the MMC sperm CASA was unreliable as methods for determining spermatozoal concentration in canine semen. Computer‐assisted spermatozoal quantification was also determined to be more precise than manual counting with the haemocytometer. Using the clinical protocol, the agreement between the haemocytometer and CASQ method was acceptable, but it was worse than in the experiments where duplicate samples and a larger volume of semen were analysed. The CASQ method may be a useful method to measure the membrane status of canine spermatozoa; however, further investigation is required. Counting spermatozoa using fluorescent microscopy and the haemocytometer may improve the efficiency of counting and the accuracy of the method.

Section: Introductionmentioning

confidence: 99%

Development of a fluorescent computer‐assisted spermatozoal quantification method and a comparison of results for manual counting with a haemocytometer and computer‐assisted semen analysis in dogs

Watts¹

2019

“…In contrast, when using cryopreserved semen, the total sperm number available for AI is usually limited and quality compensation may not be achieved. Although the minimum number of motile and normal sperm required for maximum fertility of frozen‐thawed semen is not known in dogs, insemination doses of 100–200 million progressive motile sperm are generally used with acceptable pregnancy rates (Burgess, Mitchell, & Thomas, ; Farstad & Andersen Berg, ; Linde‐Forsberg & Forsberg, , ; Thomassen, Farstad, Krogenæs, Fougner, & Andersen Berg, ; Thomassen et al., ; Mason, ; Mason & Rous, ). However, it is likely that insemination doses could be substantially reduced when using thawed semen of excellent quality (Wilson, ) whereas they may need to be increased when using samples of low quality, and even then fertility may be low.…”

Section: Introductionmentioning

confidence: 99%

Relationship between motile sperm subpopulations identified in frozen‐thawed dog semen samples and their ability to bind to the zona pellucida of canine oocytes

Martínez

Adán

Arias

et al. 2018

Contents Studies performed on ejaculates from several species have identified discrete subpopulations of motile sperm. In dogs, motile sperm subpopulations have also been described in fresh and frozen‐thawed semen. The subpopulation of the most rapid and progressively motile sperm has been suggested to be the most likely source of fertilizing spermatozoa. However, the significance of subpopulation differences among dogs and ejaculates relative to fertility is not known. The aim of this study was to investigate the relationship between the relative proportion of motile sperm subpopulations in frozen‐thawed dog semen samples and their ability to bind to the zona pellucida of canine oocytes. Multiple linear regression analysis indicated that the subpopulation of the most rapid and progressively motile sperm was significantly and positively correlated with zona pellucida‐binding assays (ZBA) outcomes: each 10% increase in this subpopulation was associated with an increase of 1.5 sperm bound per oocyte. Subpopulations of hyperactivated‐like or locally motile sperm were negatively correlated with the ZBA results. It was concluded that subpopulation differences among frozen‐thawed dog semen samples determined differences in the number of sperm bound to the ZP of canine oocytes.

“…It is today possible to routinely achieve pregnancy results of >70% with intra‐uterine artificial insemination with frozen‐thawed dog semen (Thomassen et al. ; Mason and Rous ). Tris‐based extenders have proved efficient in preserving the fertility of dog spermatozoa during preservation by cooling or freezing (Andersen ; Rota et al.…”

Section: Introductionmentioning

confidence: 99%

“…Cryopreservation of dog semen facilitates the exchange of genes between populations and makes it possible to preserve genes from valuable males for an extended time. It is today possible to routinely achieve pregnancy results of >70% with intra-uterine artificial insemination with frozen-thawed dog semen (Thomassen et al 2006;Mason and Rous 2014). Tris-based extenders have proved efficient in preserving the fertility of dog spermatozoa during preservation by cooling or freezing (Andersen 1975;Rota et al 1997).…”

Section: Introductionmentioning

confidence: 99%

Cryopreservation of Dog Semen in a Tris Extender with 1% or 2% Soya Bean Lecithin as a Replacement of Egg Yolk

Axnér

Lagerson

2016

Egg yolk is usually included in extenders used for preservation of dog semen. Lecithin is an interesting animal-protein free alternative to egg yolk for semen preservation. The aim of our study was to evaluate soya bean lecithin for cryopreservation of dog semen. Five ejaculate replicates were divided in three equal parts, centrifuged and each pellet diluted with one of the three Tris-based extenders containing 20% egg yolk, 1% soya bean lecithin or 2% soya bean lecithin. Extended semen was loaded in 0.5-ml straws, cooled and diluted a second time and frozen in liquid nitrogen vapours. Sperm motility parameters (CASA), acrosome integrity (FITC-PNA/PI) and sperm membrane integrity (C-FDA) were evaluated 5 min post-thaw and after 2 and 4 h of incubation. Total motility was significantly better in the egg yolk extender than in any of the lecithin-based extender and was better in the 1% lecithin extender than in the 2% lecithin extender. Sperm membrane integrity was significantly better in the egg yolk extender than in any of the lecithin-based extenders but did not differ significantly between the 1% and 2% lecithin extenders. Acrosome integrity was significantly better in the egg yolk extender than in the 2% lecithin extender but did not differ between the egg yolk extender and the 1% lecithin extender or between the two lecithin extenders. In conclusion, egg yolk was superior to lecithin in our study. The extender with 1% lecithin preserved sperm motility better than the extender with 2% lecithin.