Assessment of acrosome-reacted boar spermatozoa using monoclonal antibody GB 24 and propidium iodide

Sperm chromatin structure assay of bulls qualified for artificial insemination

The goal of our study was to find the relationship between fertility of bulls qualified for AI and the percentage of spermatozoa with abnormal chromatin structure as an independent parameter. We used the frozen semen of 8 mature bulls from one AI center. Each bull was represented by 3 ejaculates collected with at least 2-week intervals. Bull fertility was calculated on the basis of non-return ratio and was expressed as a scale where 100 points represented the average fertility of all the AI center's bulls. Bulls with lower or higher fertility received a lower or higher score respectively. Fertility scores of bulls used in the study ranged from 83 to 104 . Semen was processed according to the SCSA (sperm chromatin structure assay) method and was analyzed by flow cytometry. "Artificial" alpha(t) (alpha(t)=red/green+red fluorescence) and red fluorescence histograms were used for calculation of COMPalpha(t), SDalpha(t), %Red, %PeakR and MeanR parameters. The percentage of spermatozoa with abnormal chromatin ranged from 1.2% to 23.8%. A large variation among ejaculates was found for bulls with lower fertility. Fertility correlated significantly with COMPalpha(t) (-0.50, P < 0.05), SDalpha(t) (-0.55, P < 0.01), %Red (-0.53, P < 0.01), %PeakR (-0.58, P < 0.01) and MeanR (-0.45, P < 0.05). The SCSA method has a practical application in analyzing spermatogenesis disorders in bulls. If regularly applied, it allows us to identify and eliminate ejaculates with a high level of sperm chromatin abnormalities.

Ultrastructure of spermatozoa from Japanese quail

A monoclonal antibody (mAb) to epitopes on mitochondria from turkey spermatozoa cross-reacted with Japanese quail spermatozoal mitochondria. However, the pattern of binding was different from that observed for turkey sperm. The ultrastructure of quail spermatozoa was examined to determine the reason for this difference in antibody binding pattern. Light microscopy, as well as scanning (SEM) and transmission (TEM) electron microscopy, were used to study the morphology of spermatozoa from Japanese quail. Japanese quail had a sauropsid type of sperm cell, which is typical of nonpasserine birds. The spermatozoa were vermiform in shape, with a maximum width of 0.6 microm and an overall length between 230 and 250 microm. An acrosome (3.7 to 4.5 microm), nucleus (20.8 to 23.8 microm), midpiece (160 to 170 microm), and tail (40 to 60 microm) were observed. The TEM showed an acrosomal cap surrounding a perforatorium that inserted into the nucleus at the posterior end. Only a distal centriole was observed, which gave rise to a central axoneme with a 9+2 microtubular structure. The axoneme was encased by a spiraled mitochondrial sheath in the midpiece region (64 to 74% of the overall length of the sperm), and mitochondria numbers were estimated to be greater than 1,400 per sperm. In contrast, turkey sperm contain short midpieces with only 20 to 30 mitochondria per sperm. Differences in binding patterns of the mAb to turkey mitochondria between quail and turkey sperm were due to the presence of mitochondria on the exceptionally long midpieces of quail sperm.

Ultrastructure of spermatozoa from Japanese quail

A monoclonal antibody (mAb) to epitopes on mitochondria from turkey spermatozoa cross-reacted with Japanese quail spermatozoal mitochondria. However, the pattern of binding was different from that observed for turkey sperm. The ultrastructure of quail spermatozoa was examined to determine the reason for this difference in antibody binding pattern. Light microscopy, as well as scanning (SEM) and transmission (TEM) electron microscopy, were used to study the morphology of spermatozoa from Japanese quail. Japanese quail had a sauropsid type of sperm cell, which is typical of nonpasserine birds. The spermatozoa were vermiform in shape, with a maximum width of 0.6 microm and an overall length between 230 and 250 microm. An acrosome (3.7 to 4.5 microm), nucleus (20.8 to 23.8 microm), midpiece (160 to 170 micro/m), and tail (40 to 60 microm) were observed. The TEM showed an acrosomal cap surrounding a perforatorium that inserted into the nucleus at the posterior end. Only a distal centriole was observed, which gave rise to a central axoneme with a 9+2 microtubular structure. The axoneme was encased by a spiraled mitochondrial sheath in the midpiece region (64 to 74% of the overall length of the sperm), and mitochondria numbers were estimated to be greater than 1,400 per sperm. In contrast, turkey sperm contain short midpieces with only 20 to 30 mitochondria per sperm. Differences in binding patterns of the mAb to turkey mitochondria between quail and turkey sperm were due to the presence of mitochondria on the exceptionally long midpieces of quail sperm.