Data from 34 yearling Hereford or Angus bulls were used to investigate relationships of testicular size, quantitative rates of sperm production, Sertoli cell numbers, numbers of germ cells supported per Sertoli cell, and the efficiency of spermatogenesis to daily sperm output and seminal quality. Two ejaculates were collected by electroejaculation from each bull on each of 2 days/week throughout the study. The percentage of progressively motile sperm and the percentage of morphologically normal sperm were determined from aliquots of fresh semen. Additional aliquots of semen were frozen in glass ampules or plastic straws and subsequently evaluated for postthaw motility and percentage of sperm with intact acrosomes. Sertoli cell numbers, the numbers of germcells per Sertoli cell, and the efficiency of spermatogenesis were unrelated to the quality of fresh or frozen semen (P greater than 0.05). In first ejaculates, the numbers of sperm and motile sperm were related (P less than 0.05) to testicular parenchymal weight (r = 0.38, and 0.50), daily sperm production (r = 0.45 and 0.53), and spermatids per gram of testicular parenchyma (r = 0.35 and 0.34). Testicular parenchymal weight and daily sperm production also were related to daily sperm output and to the average daily motile sperm output of these bulls (P less than 0.05), but could account for less than 25% of the variability in these end points among bulls.

Introduction: The aim of this study was to propose the optimal methodology for stallion semen morphology analysis while taking into consideration the staining method, the microscopic techniques, and the workload generated by a number of samples. Material and Methods: Ejaculates from eight pure-bred Arabian horses were tested microscopically for the incidence of morphological defects in the spermatozoa. Two different staining methods (eosin-nigrosin and eosin-gentian dye), two different techniques of microscopic analysis (1000× and 400× magnifications), and two sample sizes (200 and 500 spermatozoa) were used. Results: Well-formed spermatozoa and those with major and minor defects according to Blom’s classification were identified. The applied staining methods gave similar results and could be used in stallion sperm morphology analysis. However, the eosin-nigrosin method was more recommendable, because it allowed to limit the number of visible artefacts without hindering the identification of protoplasm drops and enables the differentiation of living and dead spermatozoa. Conclusion: The applied microscopic techniques proved to be equally efficacious. Therefore, it is practically possible to opt for the simpler and faster 400x technique of analysing sperm morphology to examine stallion semen. We also found that the number of spermatozoa clearly affects the results of sperm morphology evaluation. Reducing the number of spermatozoa from 500 to 200 causes a decrease in the percentage of spermatozoa identified as normal and an increase in the percentage of spermatozoa determined as morphologically defective.

Protocols for cooling or freezing goat semen usually recommend centrifugation for seminal plasma removal. However, little is known about the effect of this process on goat sperm viability and functionality. The present study evaluated the effects of centrifugation force on the plasma membrane, acrosomes, and DNA integrity of goat semen. Four ejaculates from each of the four different Anglo Nubian male goats were used. Semen samples were obtained using artificial vagina, and immediately after collection, ejaculates were diluted using Ringer’s sodium lactate solution and split into three groups: Control (CG, without centrifugation), G1 (centrifugation 600 x g/10 min), G2 (centrifugation 1200 x g/10 min). After centrifugation, seminal plasma was removed, the sperm pellets were resuspended using Tris-egg yolk extender (80 x 106 spermatozoa/mL) and the sperm morphology was analyzed. Samples were cooled at 5°C for 5, 24, 36, and 48 h and then sperm plasma membrane and acrosome integrity (PMAI, %) and sperm DNA fragmentation index (SDF, %) were evaluated at each time-point, using a flow cytometer. Additionally, sperm movement was determined using computer semen analysis (CASA) after 5, 24, and 48 h of refrigeration period. The semen centrifugation did not induce additional sperm morphology defect or reduction in sperm kinetics in the experimental groups. Differences were not observed (p > 0.05) in PMAI and SDF among different groups, in any of each timepointof the cooling process. In conclusion, centrifugation, even at high speeds, did not affect goat sperm integrity and functionality when submitted to refrigeration process.

Carnivore semen cryopreservation procedures started with semen washing and centrifuging in culture media for seminal plasma removal and microorganisms elimination. The objective of this study was to perform coatis semen cryopreservation comparing the effects between two extenders Ham’s F-10 and M199 for washing and centrifugation before cryopreservation using Dilutris medium. Semen samples (n = 36) were collected by electroejaculation from six adult male coatis (Nasua nasua) between May and October of 2008 at the Universidade Federal de Mato Grosso Zoo. Sperm total motility (%), progressive sperm motility (0-5), plasma membrane integrity spermatozoa rates (%), and acrosome integrity (%) were analyzed. These fresh semen samples were divided in two fractions, diluted in 1 ml of Ham’s F-10 (Ham’s F-10, Nutricel S.A., Brazil) or M199 (M199, Nutricel S.A., Brazil) and centrifuged at 300 g for 10 min. The supernatant was discarded and pellets resuspended in 1 ml of Dilutris (Dilutris, Minitube®, Brazil), stored at 5ºC for 3 hours, transferred to 0.25 ml straws, placed in liquid nitrogen vapor for 20 min, and immersed in liquid nitrogen. The means/SD for fresh semen and cryopreserved semen using Ham’s F-10/Dilutris and M199/Dilutris were, respectively: 84.28 ± 11.57, 45.38 ± 27.26, and 44.61 ± 25.03 for total motility; 3.64 ± 1.44, 2.15 ± 1.14, and 2.07 ± 1.03 for progressive sperm motility; 92.76 ± 3.46, 84.69 ± 15.77, and 89.76 ± 13.97 for live spermatozoa rate; and 94.76 ± 2.89, 92.35 ± 4.73, and 90.58 ± 7.17 for acrosome integrity. No significant difference (P < 0.05) were observed between the values obtained from the Ham’s F-10/Dilutris or M199/Dilutris treatments. Both treatments demonstrated to be suitable for freezing semen from this species.

The Dag defect is one of the primary morphological defects in sperm correlating with reduced fertility. This defect is found in the spermatozoa of many livestock species. The aim of the study was to assess the morphometry of the heads of normal sperm and sperm with the Dag defect in the semen of Duroc breeding boars. Sperm morphology was examined in ten ejaculates each from 12 Duroc boars. In total, 3,600 morphologically normal sperm and 838 sperm with the Dag defect were evaluated. The area, perimeter, length and width of the sperm head were measured and these basic morphometric parameters were used to calculate four additional shape indices characterising the sperm head, i.e. ellipticity, elongation, roughness and regularity. Sperm with this defect had markedly smaller heads, 0.32 μm shorter and 0.19 μm narrower than the heads of sperm with normal morphological structure. The heads of sperm with the Dag defect also had a 1.1μm smaller perimeter and a 2.5 μm² smaller surface area than the heads of morphologically normal sperm. The Dag defect is found in boar sperm irrespective of the age of the individual. It affects the morphology of the sperm head.

Introduction: Breeding profiles at the periparturient stage in red foxes which mated naturally or were subjected to artificial insemination were retrospectively surveyed using 130 vixens during their reproductive seasons of 2012–2017 in Japan. Material and Methods: Natural mating vixens were encouraged a maximum of three times with the same male, while artificial insemination was conducted using frozen-thawed semen with the bovine semen extender as a diluent. Results: With natural mating, conception rates after one, two, and three copulations were 55.8%, 68.0%, and 85.7%, respectively, showing a significant difference between the rates for one and three copulations. Conception rates with artificial insemination were 82.4%. Mean gestation periods were between 52.1 and 53.3 days in all groups. Mean litter sizes were 3.7–4.3 cubs with natural mating, and 4.4 cubs with artificial insemination. Although some sporadic and inconsistent changes in litter sizes were noted between primiparous and multiparous groups, these were of doubtful clinical importance. Conclusion: This is the first report from Japan concerning basic breeding events of red fox vixens in captivity.

With the exception of the domestic cat, all felid species (Felidae) are currently threatened with extinction in their natural habitat. To develop effective and optimal wild cat conservation programmes with assisted reproductive technology (ART) it is necessary to combine advances from different disciplines of science, starting from the biology of the species, through research into the population and habitat, assisted reproductive technologies, establishment of gene banks, developing bioinformatic systems, and ending with biodiversity and endangered species management. In the last few years knowledge of felid reproduction has expanded considerably thanks to comparative studies utilising the domestic cat as a research model for endangered wild cats. Basic reproductive techniques utilised in both domestic cat breeding and rescuing wild felid populations that are threatened with extinction include semen collection and cryopreservation, artificial insemination, oocyte collection, in vitro maturation, in vitro fertilisation, somatic cloning, and embryo transfer. The main directions in which assisted reproductive technologies are being developed in wild cat conservation implementations and the contribution of Polish research centres in advancing these methods are presented.

Introduction The addition of low-molecular-weight antioxidants during the freezing process improves post-thaw sperm quality. The high antioxidant potential of cryopreserved semen could have a positive effect on the motility, viability, and energy status of sperm cells and their ability to bind to the zona pellucida of oocytes. The aim of the study was to determine the effects of different concentrations and combinations of vitamins E and C in a semen extender on selected quality parameters of frozen-thawed canine spermatozoa. Material and Methods The experimental material was the semen of four mixed-breed dogs. Sperm viability (motility, plasma membrane integrity, and mitochondrial function) was examined at 0, 60, and 120 min in semen samples supplemented with the extender and in the controls. Results Combined supplementation with vitamins C + E at a concentration of 200 + 200 μM /1 × 10⁹ spermatozoa had the most profound effect on total sperm motility, linear motility, and the percentage of spermatozoa with intact plasma membrane and active mitochondria. Conclusion The synergistic activity of vitamins E and C had a more beneficial influence on the quality of frozen–thawed sperm than these non-enzymatic antioxidants applied separately.