Comparison of computer-assisted sperm analysis and smartphone-applied sperm analysis for evaluation of frozen-thawed bull semen.

This study aims to compare the efficacy of computer-assisted sperm analysis (CASA) and smartphone-applied sperm analysis (SASA) in assessing the quality of frozen-thawed bull semen. A total of 75 straws (n = 75) semen samples were used from different production batches of five Holstein bulls. The semen analyses were conducted in three groups: Group I (CASA-37°C), semen samples were evaluated using the CASA system at 37°C (n = 25); Group II (SASA-25°C), semen samples were assessed using the SASA system at a temperature of room heat (25°C) (n = 25); and Group III (SASA-37°C), semen samples were evaluated using the SASA system at 37°C (n = 25). The frozen-thawed bull semen samples were analysed in terms of total motility (TM), progressive motility (PM), immotile, velocity average path (VAP), velocity curve linear (VCL), velocity straight line (VSL) and sperm concentration. There was no significant difference between the groups in terms of spermatozoa concentration (p > .05). However, significant differences among the groups were observed for total motile spermatozoa values (p < .001). Values of progressive motile spermatozoa were lower in Group I and Group II compared to Group III (p < .001). The immotile spermatozoa values were significant between the groups (p < .001) and were found to be proportional to total motile spermatozoa values. Additionally, the VAP, VCL and VSL values were comparable between Group II and Group III, but lower when compared to Group I. In conclusion, the results of the study demonstrate that the Sperm Cell™ system can accurately analyse the concentration of frozen-thawed bull semen. The analyses performed at room temperature indicate a parallelism between the PM value and CASA results. However, it is thought that SASA devices require a series of standardization studies in different semen extenders, different sample concentrations and different animal species, analogous to the standardization evolution process of CASA devices in semen analysis.

Reaction time as a libido indicator and its relation to pre-freeze and post-thaw sperm quality in bulls.

Libido and sperm quality output relationship is already not clear in farm animals. The present study compared reaction time (RT) as a libido indicator and the pre-freeze and post-thaw sperm quality of AI bulls. Before the collection of ejaculates (n = 53, from 22 AI bulls [4.2 ± 1 years of age]), RTs were collected using a chronometer as the interval between the bull's arrival at the semen collection area and his first false mount (FM) on another male. The ejaculates were examined for their volume, concentration and motility. Subsequently, all aliquots were diluted with a commercial semen extender and equilibrated for 3 h before freezing. Frozen semen samples were thawed and examined for sperm kinematics using CASA, plasma membrane and acrosome integrity of sperm (PMAI) by flow cytometry. Additionally, the temperature humidity index (THI) values were assessed during the study. Multiple linear regression analysis was used to analyse the data. The results indicated that THI had a significant effect on libido (p < .001). However, libido had no effect on either pre- or post-thaw sperm quality parameters except for the velocity of the average pathway (VAP) (p < .05). Therefore, relying solely on RT -libido- as an indicator of bull sperm quality at AI stations may not be reliable, as it is a complex behavioural assessment.

Quality assessment of frozen bull semen with the precursor A-kinase anchor protein 4 biomarker.

In this study, the quality of frozen bull semen was evaluated with the proAKAP4 level test. Sixty straws of frozen bull semen from various batches (n = 30) belonging to six bulls were used in the current study. The frozen bull semen samples were analysed in terms of proAKAP4 levels, sperm morphology and sperm movement parameters at hour 0 and hour 3 after thawing. The semen samples were divided into three groups according to the proAKAP4 levels: low concentration (<25 ng/10x106 spermatozoa), moderate concentration (25 to 39 ng/10x106 spermatozoa) and high concentration (≥40 ng/10x106 spermatozoa). A positive correlation was found between the proAKAP4 level and total motility (TM3 ), progressive motility (PM3 ), VSL3 and VCL3 values obtained after the third-hour thermoresistance test (p < .05). There was a negative correlation between the percentage of sperm abnormal tail and the proAKAP4 level (p < .01). In addition, it was observed that the semen samples with proAKAP4 concentrations of 25 ng/106 spermatozoa and higher preserved the TM3 and PM3 motility characteristics. In conclusion, the proAKAP4 has the potential to become a biomarker protein to evaluate in the quality analysis of frozen-thawed semen.

Gallic and carnosic acids improve quality of frozen-thawed ram spermatozoa.

The objective was to determine effects of gallic acid (GA) and carnosic acid (CA), present in carob pods and rosemary extract respectively, on frozen-thawed ram spermatozoa. Thirty ejaculates were collected from five Merino rams, pooled, diluted in Tris-based extender and divided into five equal portions containing: 0.05 or 2 mM of GA; 0.05 or 0.2 mM of CA; or no additive (control). Extended semen was equilibrated at +4°C, loaded into straws, held 5 cm above liquid nitrogen for 12 min then plunged. Computer-aided sperm analysis was used to assess motility, whereas flow cytometry was used to assess high mitochondrial membrane potential (HMMP) and percentages of spermatozoa with plasma membrane and acrosome integrity (PMAI). Spermatozoa supplemented with 2 mM GA had greater total motility than control spermatozoa (39.9 ± 3.01 vs. 29.2 ± 1.31%, mean ± SEM, p < .05). The PMAI was greatest in 0.2 mM CA (13.3 ± 0.68%), whereas HMMP was highest in 0.05 mM CA but lowest in control (22.9 ± 4.95 and 11.4 ± 3.64% respectively; p < .05). In conclusion, for cryopreservation of ram semen in Tris-based extender, supplementation with 2 mM GA increased post-thaw motility, whereas supplementation with 0.05 mM CA enhanced mitochondrial function.

Effect of serum anti-Müllerian hormone levels on the superovulation response in Holstein heifers.

BACKGROUND: Anti-Müllerian hormone (AMH) holds potential as a biomarker for assessing the superovulation (SO) response in cattle. Nonetheless, there exists scant information regarding this aspect in the literature concerning dairy heifers. Given this gap, our objective is to explore the viability of AMH as an indicator for gauging the SO response specifically in Holstein heifers. Furthermore, our aim encompasses examining the variations in AMH levels within the same individuals before and after undergoing SO. METHODS: The study included 41 Holstein heifers. All heifers were superovulated and blood samples were taken both before and after the SO protocol. RESULTS: The findings revealed that the mean values of serum AMH concentrations before and after SO were 0.122 ng/mL (0.093-0.248 ng/mL) and 0.119 ng/mL (0.084-0.170 ng/mL), respectively. AMH concentrations in heifers were stratified into low (<0.106 ng/mL), medium (0.107-0.126 ng/mL) and high (>0.127 ng/mL) categories both before and after SO. CONCLUSIONS: There was no significant correlation between AMH levels in the heifers both before and after SO treatment with the number of follicles, corpora lutea, total embryos collected or embryos transferred (p > 0.05). Furthermore, this study showed that serum AMH concentrations in Holstein heifers did not change after SO treatment. In this study, as AMH levels in Holstein heifers were in a narrow range, a relationship between AMH and SO response could not be determined. In future studies, we believe that it would be more useful to plan more studies in Holstein donor heifers, taking into account the number of animals and AMH levels.

Assessing the Relationship between proAKAP4 Level and Longevity of Sexed Sperm Quality after Thawing.

ProAKAP4 is a sperm structural protein that regulates motility through the PKA-dependent cAMP signaling pathway, which is synthesized as an X chromosome-linked member of the gene family. This study aims to determine the optimal level of proAKAP4 for evaluating sexed semen through investigating its relationship with the longevity of sperm quality in sexed Holstein bull sperm. A total of 30 sexed sperm samples (bearing X chromosomes) from 30 distinct Holstein bulls (n = 30) were analyzed. The frozen bull sperm samples were assessed for their proAKAP4 levels, mitochondrial membrane potential, plasma membrane and acrosome integrity (PMAI), and spermatozoa movement parameters at hours 0 and 3 after thawing. The proAKAP4 levels in the sexed sperm samples ranged from 16.35 to 72.10 ng/10 M spz, with an average of 37.18 ± 15.1 ng/10 M spz. A strong positive correlation was observed between proAKAP4 levels and total motility, progressive motility, PMAI, high mitochondrial membrane potential, VAP, and VCL values after 3 h of incubation, when compared to post-thaw analyses. The results also reveal that spermatozoa with proAKAP4 levels of ≥40 ng/10 M spz exhibit higher quality. In conclusion, the level of proAKAP4 in sexed sperm aligns with previous studies and shows potential as a biomarker for assessing the longevity of sexed sperm quality.