Comparison of semen variables, sperm DNA damage and sperm membrane proteins in two male layer breeder lines

Comparative assessment of thawing methods for frozen rooster sperm

Introduction

Cryopreservation, widely used in commercial poultry breeding, often reduces sperm motility, viability, and DNA integrity due to cryopreservation-induced damage. This study evaluates the effects of water bath and dry thawing systems on the post-thaw quality of rooster spermatozoa, addressing these challenges and exploring methods to enhance sperm quality.

Methods

The study compared the performance of water bath and dry thawing systems, both operated at 37°C for 30 s. Post-thaw assessments included sperm motility, morphology, kinematic characteristics, and DNA integrity. Key parameters such as total motility, progressive motility, curvilinear velocity (VCL), average path velocity (VAP), straight-line velocity (VSL), viability, morphological abnormalities, and DNA damage metrics were analyzed.

Results

The dry thawing system significantly improved sperm quality compared to the water bath method. Total motility and progressive motility were higher in the dry thawing system (82.38 and 33.18%, respectively) compared to the water bath method (68.14 and 21.20%). Kinematic parameters, including VCL (79.41 vs. 66.49 μm/s), VAP (47.52 vs. 37.42 μm/s), and VSL (27.18 vs. 21.59 μm/s), were superior in the dry thawing system. Viability improved (82.2 vs. 73.7%), while morphological abnormalities were reduced (23.9 vs. 35.8%). DNA integrity metrics, such as Tail DNA (%; 77.37 vs. 81.11%) and Olive Tail Moment (15.28 vs. 16.93), also showed reduced damage.

Discussion

The dry thawing system offers significant operational advantages, including portability, contamination-free operation, and consistent temperature maintenance, making it ideal for on-site applications. These features, combined with its ability to enhance sperm quality, highlight the dry thawing system as an effective alternative for poultry breeding. Its adoption could improve artificial insemination outcomes and address challenges associated with cryopreservation-induced damage during thawing.

Estimation of the seminal parameters of rooster and its association with fertility traits in synthetic dam line

The objective of the present study was to assess the seminal parameters of rooster and its association with fertility traits (%), viz., hatchability of the fertile egg set (HFES), hatchability of the total egg set (HTES), and fertility (FERT). The data records pertained to traits of interest were obtained from various registers maintained at Poultry farm, of the Department of Animal Genetics and Breeding, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar (India). The relationship between seminal and fertility characteristics was investigated using regression analysis and correlation. Moreover, the efficacy of seminal characteristics to distinguish between roosters with low and high fertility traits was evaluated using linear discriminant analysis (LDA). The findings showed that reproductive traits and seminal characteristics were significantly (P < 0.05) correlated. The LDA showed that the seminal parameters can effectively separate the roosters into those with high and poor reproductive features. It was revealed from LDA that seminal features showed higher classification accuracy for FERT (80.77%). Hatchability is dependent on eggs that have been artificially incubated; hence, these crucial traits are comparatively weaker for HTES (65.38%) and HFES (67.31%). Cross-validation of the seminal parameter LDA corroborated the aforementioned and related conclusions. It is suggested that the studied LDA function may be utilised to choose genotypes with improved reproductive traits based on seminal variables.

Comparative Proteomics and Phosphoproteomics Analysis Reveal the Possible Breed Difference in Yorkshire and Duroc Boar Spermatozoa

Sperm cells are of unique elongated structure and function, the development of which is tightly regulated by the existing proteins and the posttranslational modifications (PTM) of these proteins. Based on the phylogenetic relationships of various swine breeds, Yorkshire boar is believed to be distinctly different from Duroc boar. The comprehensive differential proteomics and phosphoproteomics profilings were performed on spermatozoa from both Yorkshire and Duroc boars. By both peptide and PTM peptide quantification followed by statistical analyses, 167 differentially expressed proteins were identified from 1,745 proteins, and 283 differentially expressed phosphopeptides corresponding to 102 unique differentially phosphorylated proteins were measured from 1,140 identified phosphopeptides derived from 363 phosphorylated proteins. The representative results were validated by Western blots. Pathway enrichment analyses revealed that majority of differential expression proteins and differential phosphorylation proteins were primarily concerned with spermatogenesis, male gamete generation, sperm motility, energy metabolism, cilium morphogenesis, axonemal dynein complex assembly, sperm–egg recognition, and capacitation. Remarkably, axonemal dynein complex assembly related proteins, such as SMCP, SUN5, ODF1, AKAP3, and AKAP4 that play a key regulatory role in the sperm physiological functions, were significantly higher in Duroc spermatozoa than that of Yorkshire. Furthermore, phosphorylation of sperm-specific proteins, such as CABYR, ROPN1, CALM1, PRKAR2A, and PRKAR1A, participates in regulation of the boar sperm motility mainly through the cAMP/PKA signal pathway in different breeds, demonstrating that protein phosphorylation may be an important mechanism underlying the sperm diversity. Protein–protein interaction analysis revealed that the 14 overlapped proteins between differential expression proteins and differential phosphorylation proteins potentially played a key role in sperm development and motility of the flagellum, including the proteins ODF1, SMCP, AKAP4, FSIP2, and SUN5. Taken together, these physiologically and functionally differentially expressed proteins (DEPs) and differentially expressed phosphorylated proteins (DPPs) may constitute the proteomic backgrounds between the two different boar breeds. The validation will be performed to delineate the roles of these PTM proteins as modulators of Yorkshire and Duroc boar spermatozoa.

Identification of sperm-specific proteins associated with high fertility of Punjab Red and RIR x Local cross roosters with SDS-PAGE and Immunoblotting

The present study aimed at characterization of fertility-associated proteins in PR and RIR x Local roosters and was conducted on two generations of birds. Roosters were divided into high- (>50%) and low-fertility groups (<50%) based on sperm function tests and fertility rate in both the generations. Polyclonal antibodies were raised in rabbits against sperm proteins of first generation highly fertile roosters and tested for characterization of fertility-associated sperm proteins in the second generation of same roosters. IgG fraction against proteins (anti-SP IgG) was reacted with sperm proteins of both high and low fertile roosters of second generation on immunoblots. SDS-PAGE of sperm extracts of PR and RIR x Local cross breeds resulted in resolution of 12 and 23 proteins on 12% acrylamide gels and anti-SP IgG reacted only with 8 and 9 sperm proteins of PR and RIR x Local cross roosters on immunoblots. The SDS-PAGE and immunoblotting analysis also indicated a variation in sperm proteins among two breeds and high/low fertile roosters. It can be concluded that the selection of roosters on the based on proteins of 65/ 25; 70/ 46/ 30 kDa may be specifically associated with high fertility of PR and RIR x Local cross, respectively. The proteins 62 kDa (PR) and 40kDa (RIR x Local cross) may be specifically responsible for low fertility.

Characterization of fertility associated sperm proteins in Aseel and Rhode Island Red chicken breeds

This study focused on characterization of fertility associated proteins in Aseel and RIR roosters and was conducted on two generations of birds. Roosters were divided into high (>50%) and low fertility groups (<50%) based on sperm function tests and fertility rate in both the generations. Polyclonal antibodies were raised in rabbits against sperm proteins of first generation highly fertile roosters and tested for characterization of fertility associated sperm proteins in the second generation of same roosters. IgG-fraction against proteins (Anti-SP-IgG) was reacted with sperm proteins of both high and low fertile roosters of second generation on immunoblots. Sperm proteins present in highly fertile roosters were further characterized by Mass Spectrometry (MS). Use of SDS-PAGE for evaluation of sperm extracts of Aseel and RIR breeds resulted in resolution of 16 and 10 proteins on 12% acrylamide gels. Anti-SP-IgG reacted with eight and ten sperm proteins of Aseel and RIR roosters on immunoblots. The SDS-PAGE and immunoblotting analysis also indicated a variation in sperm proteins among two breeds and high/low fertile roosters. The MS analysis indicated matching of 20, 30, and 20, 25 kDa proteins (associated with high fertility rate) of Aseel and RIR roosters with immunoglobulin kappa chain variable, phospholipase A₂ (PLA2), hypothetical N332-08551 partial and cystatin like partial proteins with a top score of 41, 46, 52 and 43, respectively. Considering the function and importance of matching proteins in male reproduction, these proteins may be further explored as potential markers for fertility evaluation of Aseel and RIR roosters.

Dwarf chickens with low monocytes/macrophages phagocytic activity show low antibody titers but greater performance

Monocytes/macrophages phagocytosis has key roles in inflammatory responses. However, systematic research on the effects of monocytes/macrophages phagocytosis on production and reproductive performance in dwarf chickens is lacking. In this study, we developed the HCT-8-MTT method to detect monocytes/macrophages phagocytosis product (PP) which was accuracy, flexible, and saving time. Based on PP in 990 dwarf chickens (890 hens and 100 cocks), chickens were divided into high phagocytosis product group (HPPG) and low phagocytosis product group (LPPG). In production performance, chickens in LPPG have higher laying rate at 24 wk and 71 wk and higher average egg weight at 23 wk and 24 wk than in HPPG (P < 0.05). The levels of follicle-stimulating hormone and luteinizing hormone were higher in LPPG than in HPPG at 58 wk (P < 0.01). In the reproductive performance, the fertilization rate in LPPG was higher than that in HPPG at 45 wk, 49 wk, and 53 wk (P < 0.05). Chickens in LPPG have higher hatchability than HPPG at 45 wk and 49 wk (P < 0.05). In LPPG, the mRNA expression levels of follicle-stimulating hormone receptor and CD9 in the follicle were higher than HPPG (P < 0.05). In the immune response, chickens with higher PP levels showed higher antibody titers for the avian influenza virus H9 inactivated vaccine (P < 0.01). Therefore, monocytes/macrophages PP was positively associated with antibody titers and negatively related to production and reproductive performance, and these findings have practical applications for the optimization of production in the poultry industry.