Effect of proctodeal gland foam on sperm kinetics in Japanese quail (Coturnix japonica).

The proctodeal gland of the male Japanese quail produces thick foam that accompanies semen when it is transferred to the female. It is thought that this foam enhances fertilization by improving the motility of the sperm, but reports are conflicting because the effect of foam on sperm motility has only been assessed subjectively The velocity of individual sperm was not able to be measured accurately, variations were large, and small changes in motility could not be accurately evaluated. So, we tested the hypothesis that foam affects the motility of spermatozoa of Japanese quail by analyzing motility objectively using computer-assisted semen analysis and determining changes in sperm kinetics in the presence of different concentrations of proctodeal gland foam. The addition of 5% or 10% foam to the sperm suspension increased (P < 0.05) all sperm kinetic parameters (the curvilinear velocity, straight line velocity, the velocity of the average path, linearity, straightness, and beat cross frequency). As a result, the percentage of motile and progressive motile sperm also increased. All these parameters declined (P < 0.05) with a further increase in the concentration of foam to 15% and 20%. Furthermore, this effect was similar in males that were 8, 16, or 26 weeks of age. We conclude that sperm motility is enhanced by proctodeal gland foam, and this enhancement depends on its concentration.

In vitro initiation of the acrosome reaction in the emu (Dromaius novaehollandiae).

1. An assessment of the efficiency of the acrosome reaction (AR) provides an important predictor of the fertilizing potential of semen and for diagnosis of the causes of infertility. A standardized protocol was therefore developed for initiation of the acrosome reaction in emu spermatozoa in vitro, and the role of CaCl2 or perivitelline membrane (PVM) proteins in determining the outcome of the reaction was investigated. 2. The acrosome reaction (assessed by FITC-PNA) was successfully induced in live spermatozoa by incubation for 2 min in NaCl-TES medium supplemented with 5 mM CaCl2. The maximum response was 32% live acrosome-reacted spermatozoa (LAR) achieved after 10 min incubation. 3. Compared to the outcome with 5 mM CaCl2 or PVM protein alone, the response was significantly better with a combination of PVM protein and CaCl2. 4. A significant variation in the percentage of LAR spermatozoa among individual males was observed. No treatment affected the percentage of dead acrosome-reacted spermatozoa. 5. The results emphasize the important role played by both PVM proteins and Ca(2+) in the in vitro initiation of the acrosome reaction.