Effects of Kaempferia parviflora supplement on semen production and reproductive system of boar

Kaempferia parviflora (KP) grows exclusively in Thailand. The plant is traditionally used in men for its supposed fertility-enhancing properties. However, its effects on improving reproduction in farm animals such as boar have not been investigated. The aim of this study was to investigate 1) the effects of KP supplement on semen quantity and quality, the reproductive organ weight and histology, and sexual behavior of boar and 2) the testosterone-like effect of KP by comparing with the effect of the male reproductive hormone, testosterone. With this purpose, 12 boar at 32 weeks of age were randomly assigned to receive: (1) a control diet; (2) a control diet supplemented with 1% of KP; (3) a control diet with a single injection of testosterone (0.2mg/kg body wt.), daily for one month. Boar, which received KP had a greater semen volume than the control group and that of the hormone-treated group (p<0.05). Testicular weight of the KP group and the group that received testosterone were lesser than that of the control group (p<0.05). However, there was no singnificant difference in testicular histology among the groups. KP feeding and testosterone injection were likely to increase serum testosterone level. However, this did not reach statistical significance. Neither KP feeding nor testosterone injection increased libido of boar. We conclude that dietary treatment with KP has no adverse effects on the observed reproductive system and that it has no testosterone-like effect on reproduction of boar.