Influence of Semen Collection Frequency and Seasonal Variations on Fresh and Frozen Semen Quality in Thai Native Roosters

SIMPLE SUMMARY: Semen collection frequency and season are the primary factors influencing the ability to effectively utilize artificial insemination technology during rooster fertility to ensure semen quality and a usable number of sperm for cryopreservation. In this present study, we first conducted an experiment for one year to study the influence of semen collection frequency (once, twice, and thrice per week) and seasonal factors on the quality of fresh and frozen semen from Thai native roosters raised under an open-housed system. The results showed that neither fresh nor frozen semen quality was affected by semen collection frequency, but they were influenced by season. Semen collection can be conducted three times per week in native Thai roosters without affecting semen quality while maximizing sperm production. However, the rainy season negatively affected sperm concentration. The highest sperm production was obtained during the winter compared to the summer and the rainy season. Moreover, the decreased sperm motility of frozen-thawed semen obtained in the summer season might be related to the higher malondialdehyde concentration. ABSTRACT: This study aimed to determine the effects of the frequency of semen collection (once, twice, and thrice weekly) and seasonal variations on the fresh and frozen semen quality of Thai native roosters throughout the year. Data on temperature and humidity were collected and used to calculate the temperature–humidity index (THI). The average temperature and THI were lower in the winter than in the rainy season and the summer (p < 0.05). In contrast, the average relative humidity was not different among the seasons but was higher in the rainy season (p > 0.05). None of the fresh or frozen semen quality parameters were influenced by the frequency of semen collection, but the season did have an effect. The highest sperm concentration was obtained in the winter (p < 0.05). In contrast, the lowest sperm concentration was found during the rainy season, which presented the highest humidity. Regarding the frozen semen quality, the highest malondialdehyde concentration and the lowest motility were found in the summer (p < 0.05). In conclusion, semen collection can be conducted thrice per week for a consecutive year without affecting semen quality while maximizing sperm production. However, the highest sperm production was obtained in the winter, which is also a suitable season for producing semen for cryopreservation.