• Asian-Australasian Journal of Animal Sciences
• /
• 제13권1호
• /
• pp.10-18
• /
• 2000

This paper describes the magnetic orientation of the intact and demembranated bull sperm treated by DTT or heparin in a 5,400 G static field. Semen samples collected from four bulls (Japanese Black) were mixed to the same sperm density. One percentage triton X-100 was used to extract the plasma membrane. The intact and demembranated sperm suspensions were treated with 20, 200, 2,000 mM DTT, 100, 1,000 or 10,000 units heparin solutions at $4{^{\circ}C}$ for 6 days. The decondensation of the sperm nuclei treated by DTT or heparin was examined by measuring the sperm head area at 1, 3, and 6 days. After measuring the area, each sperm sample was exposed to a 5,400 G static magnetic field generated by Nd-Fe-B permanent magnets for 24 hours at room temperature. Results showed that the decondensation of bull sperm nuclei was not induced by the heparin treatment, however, incomplete decondensation was induced by the DTT treatment. During the magnetic orientation, bull sperms treated by DTT or heparin had low percentages of long axis perpendicular to the magnetic lines of force. However, different aspects were obtained for long axis perpendicular orientations following treatment of DTT or heparin. Through the DTT treatment, the decline of long axis perpendicularly oriented percentages was due to the increase of long axis parallel orientation with the head of the flat plane perpendicular to the magnetic lines of force, whereas, using the heparin treatment, the decline of long axis perpendicular orientation was due to the increment of long axis parallel orientation with the head of the flat plane parallel to the magnetic lines of force. Also, percentages of the head of the flat plane perpendicular were decreased by the heparin treatment. These findings suggest that maintaining the structure of protamine in the chromatin is necessary for the sperm head to orient with its flat plane perpendicular, and maintaining the disulfide bond in the chromatin is necessary for the long axis of sperm to orient perpendicularly.

• Asian-Australasian Journal of Animal Sciences
• /
• 제13권2호
• /
• pp.167-175
• /
• 2000

This paper describes the magnetic orientation of bull sperm separated into the head and the flagellum treated by DTT or heparin in a 5,400G static field. Semen samples collected from four bulls (Japanese Black) were mixed to the same sperm density. One percentage triton X-100 was used to extract the plasma membrane. The intact and demembranated sperm suspensions were treated with 20, 200, 2,000 mM DTT, 100, 1,000 or 10,000 units heparin solutions at $4^{\circ}C$ for 6 days. The decondensation of the sperm nuclei treated by DTT or heparin was examined by measuring the head area at 1, 3 and 6 days. After measuring the area, each sample was exposed to a 5,400G static magnetic field generated by Nd-Fe-B permanent magnets for 24 hours at room temperature. Results showed that the sperms were separated into the head and the flagellum through the DTT treatment. Almost of the separated heads showed that their long axis oriented perpendicularly to the magnetic lines of force, and most of the long axis perpendicularly oriented heads showed that their flat plane oriented perpendicularly in a 5,400G magnetic field. Also, the demembranation of the head tended to increase those perpendicular orientations, while those perpendicular orientations of the head declined with the decondensation of the sperm nuclei. These findings suggest that strong magnetic anisotropy for the perpendicular orientation of the long axis and the flat plane of the head occurs in the sperm nuclei in a 5,400G magnetic field. The separated flagellum showed lower parallel orientation, and the separated and demembranated flagellum showed parallel orientation to the magnetic lines of force in this magnetic field. These findings suggest that weak magnetic anisotropy of the parallel orientation of the flagellum occurs in the inside components in a 5,400G field.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권2호
• /
• pp.155-162
• /
• 2001

Effect of the north (N) or south pole (S) of a magnet and dithiothreitol (DTT) or heparin sodium (H) on the orientation of bull sperm were studied. Sperm were collected from four Japanese Black bulls of Okinawa Prefectural Livestock Experimental Station were treated with various concentrations of DTT or H during the first and sixth days and were then exposed them to N or S with a magnetic field of 3,000 Gauss for 24 hours. Experimental results showed that both N and S significantly increased the perpendicular oriented percentage of bull sperm in most treatments not treated or treated with DTT or H. Anisotropy of magnetic field of bull sperm was the main cause which induced them to orient perpendicular to the magnetic direction. The results of the experiment also showed that, in most cases, the two polarities had the same effect on the orientation of bull sperm. However, in some cases, N exerted a stronger effect on the perpendicular percentage of bull sperm than S, such as with the 20 mM DTT treatment at the first and sixth days and the 100 units H treatment at the sixth day. These cases showed that the perpendicular oriented percentage of bull sperm at N was significantly higher than that of S. It was only the 100 units heparin treatment at S both at the first and sixth days that upward perpendicular orientation was higher than that at N. This might be due to the fact that protamin-DNA structure of a small number of bull sperm nuclei slightly changed because of heparin action.