Reproductive exocrine and endocrine profiles and their seasonality in male langur monkeys (Presbytis entellus entellus).

The reproductive exocrine and endocrine profiles in male langurs are reported with an emphasis on seasonality. The animals showed positive response to electroejaculation throughout the year. The sperm concentration varied between 10-383 x 10(6)/ejaculation with wide fluctuations all through the year. No appreciable changes in the motility and percent live sperm were observed throughout the year. The levels of seminal fructose and magnesium remained unchanged throughout the year, while acid phosphatase showed wide fluctuations. Citric acid showed elevation during February and March and LDH showed elevated levels during April and May. The annual range of serum testosterone was 6-34 nMol/l with a peak during July. Cortisol ranged between 575-1587 nMol/l and prolactin ranged between 107-900 mU/l. Wide fluctuations were observed in hormonal levels. No seasonality was exhibited in the seminiferous tubule diameter, nuclear diameter of Sertoli cells and Leydig cells, and the cholesterol, glycogen, and sialic acid contents of testis. None of the parameters studied have shown any correlation with season. The results suggest that the male langurs lack seasonality in their reproductive exocrine and endocrine profiles and thus could be used as model for research in human reproduction.