Michaela Petrovičová

Semen quality plays a crucial role in poultry production; however, it may be impaired by the presence of numerous bacterial species. This study researched the impact of bacterial contamination of Lohmann brown rooster semen on the biochemical parameters of seminal plasma to evaluate its potential consequences on the sperm progressive motility. Semen was collected from 27 stud roosters, and the sperm concentration and progressive motility were measured using computer-assisted semen analysis (CASA). Seminal plasma was separated, and selected biochemical parameters were measured using commercially available assays. An aliquot of each semen sample was cultured, the colonies were counted and the MALDI Biotyper was used for bacterial identification. The samples were divided into three categories based on their sperm progressive motility and the data were compared and statistically evaluated. Moreover, Pearson’s correlation analysis was performed. The results showed that the lower the sperm progressive motility, the higher the level of colony-forming units. Moreover, sperm concentration was significantly higher (p < 0.05) in the group with the highest bacterial occurrence and the lowest proportion of progressively motile spermatozoa. Calcium, magnesium, creatinine, uric acid, alkaline phosphatase, and total proteins significantly changed in semen samples with the lowest proportion of progressive motility. In conclusion, seminal plasma biochemistry may mirror changes occurring in semen as a result of bacterial presence in the reproductive tract of poultry.

4-methylumbelliferone (4MU) has been suggested as a potential therapeutic agent for a wide range of neurological diseases. The current study aimed to evaluate the physiological changes and potential side effects after 10 weeks of 4MU treatment at a dose of 1.2 g/kg/day in healthy rats, and after 2 months of a wash-out period. Our findings revealed downregulation of hyaluronan (HA) and chondroitin sulphate proteoglycans throughout the body, significantly increased bile acids in blood samples in weeks 4 and 7 of the 4MU treatment, as well as increased blood sugars and proteins a few weeks after 4MU administration, and significantly increased interleukins IL10, IL12p70 and IFN gamma after 10 weeks of 4MU treatment. These effects, however, were reversed and no significant difference was observed between control treated and 4MU-treated animals after a 9-week wash-out period.

This study aimed to characterize the bacterial profiles and their association with selected semen quality traits among two chicken breeds. Thirty Lohmann Brown and thirty ROSS 308 roosters were selected for semen quality estimation, including sperm motility, membrane and acrosome integrity, mitochondrial activity, and DNA fragmentation. The oxidative profile of the semen, including the production of reactive oxygen species (ROS), antioxidant capacity, protein, and lipid oxidation, were assessed as well. Moreover, the levels of pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interleukins 1 and 6 (IL-1, IL-6) and C-reactive protein, as well as the concentrations of selected antibacterial proteins (cathelicidin, β-defensin and lysozyme) in the seminal plasma were evaluated with the enzyme-linked immunosorbent assay. The prevailing bacterial genera identified by the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were Citrobacter spp., Enterococcus spp., Escherichia spp. and Staphylococcus spp. While the bacterial load was significantly higher in the ROSS 308 line (p < 0.05), a higher number of potentially uropathogenic bacteria was found in the Lohmann Brown roosters. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains, particularly to ampicillin, tetracycline, chloramphenicol, and tobramycin. Furthermore, Lohmann Brown ejaculates containing an increased proportion of Escherichia coli presented with significantly (p < 0.05) elevated levels of TNF-α and IL-6, as well as ROS overproduction and lipid peroxidation. Inversely, significantly (p < 0.05) higher levels of β-defensin and lysozyme were found in the semen collected from the ROSS 308 roosters, which was characterized by a higher quality in comparison to the Lohmann Brown roosters. In conclusion, we emphasize the criticality of bacteriospermia in the poultry industry and highlight the need to include a more complex microbiological screening of semen samples designated for artificial insemination.

Artificial insemination, as an essential pillar of the modern poultry industry, primarily depends on the quality of semen collected from stud roosters. Since the collection and storage of ejaculates is not a sterile process, antimicrobial agents have become essential supplements to semen extenders. While the use of traditional antibiotics has been challenged because of rising bacterial resistance, natural biomolecules represent an appealing alternative because of their antibacterial and antioxidant properties. As such, this study strived to compare the effects of 50 μmol/L curcumin (CUR) with 31.2 µg/mL kanamycin (KAN) as a conventional antibiotic on rooster sperm quality in the presence of Salmonella enterica, Escherichia coli and Pseudomonas aeruginosa. Changes in sperm structural integrity and functional activity were monitored at 2 and 24 h of culture. Computer-assisted semen analysis revealed significant sperm motility preservation following treatment with KAN, particularly in the case of Salmonella enterica and Pseudomonas aeruginosa (p < 0.001) after 24 h. On the other hand, CUR was more effective in opposing ROS overproduction by all bacteria (p < 0.05), as determined by luminol-based luminometry, and maintained sperm mitochondrial activity (p < 0.001 in the case of Salmonella enterica; p < 0.05 with respect to Escherichia coli and Pseudomonas aeruginosa), as assessed by the fluorometric JC-1 assay. The TUNEL assay revealed that CUR readily preserved the DNA integrity of rooster sperm exposed to Salmonella enterica (p < 0.01) and Escherichia coli (p < 0.001). The bacteriological analysis showed higher efficiency of KAN in preventing the growth of all selected bacterial species (p < 0.0001) as opposed to CUR. In conclusion, CUR provided protection to rooster spermatozoa against alterations caused by uropathogens, most likely through its antioxidant activity. Hence, CUR supplementation to poultry semen extenders in combination with properly selected antibacterial substances may become an interesting strategy in the management of bacterial contamination during semen storage.

This study focused on the identification of naturally occurring bacteria in the reproductive fluid and impact on the quality of ejaculates obtained from the turkey breed British United Turkeys (BUT) Big 6 (n = 60). We determined possible relationships between the bacterial load and advanced sperm quality parameters that are important for effective artificial insemination and high fertility, as well as the concentration of selected antimicrobial proteins and pro-inflammatory markers of turkey semen. Sperm motility was assessed with computer-assisted sperm analysis (CASA), while the membrane and acrosome integrity were examined with smearing and staining methods. Reactive oxygen species (ROS) generation was quantified via luminometry, sperm DNA fragmentation was evaluated using the TUNEL assay, and the JC-1 assay was applied to evaluate the mitochondrial membrane potential. Cell lysates were prepared to investigate the extent of lipid and protein oxidation. Furthermore, levels of interleukins 1 and 6 (IL-1, IL-6), C-reactive protein, cathelicidin, and β-defensin were quantified in the seminal plasma using the ELISA method. The most dominant species identified by the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry was Escherichia coli, Proteus mirabilis, Staphylococcus lentus, and Citrobacter braakii. The bacterial load had a negative effect on the sperm motility (p < 0.001), as well as membrane (p < 0.05) and acrosome integrity (p < 0.01). A strong positive relationship between the bacterial load and DNA fragmentation (p < 0.001) was detected as well. Positive associations were recorded between the increasing presence of bacteria, ROS overgeneration (p < 0.001), and a subsequent oxidative damage to the proteins (p < 0.001) and lipids (p < 0.01). It was revealed that the antimicrobial peptides β-defensin (p < 0.001) and cathelicidin (p < 0.001) had a positive relationship with the motility. In contrast, pro-inflammatory markers, such as IL-1 (p < 0.001) and IL-6 (p < 0.001), had a negative impact on the motion behavior of turkey spermatozoa. Our results suggest that the semen quality may be notably affected by the bacterial quantity as well as quality. It seems that bacteriospermia is associated with inflammatory processes, oxidative stress, sperm structural deterioration, and a subsequent risk for a failed artificial insemination in turkey breeding.