Geographic Variation in Testicular Morphometrics, Androgen Receptor Expression and Anti-Müllerian Hormone Levels in the Intermediate Roundleaf Bats across Distinct Regions in Thailand.

The hipposideros larvatus (intermediate roundleaf bat) is one of the insectivorous bats which has an agro-ecological role as a controller of the insect population. The reproductive patterns of H. larvatus are intricately linked to its ecological role and survival. An understanding of the testicular morphology can contribute to conservation for this species particularly in areas where its populations might be declining or under threat. However, these bats may also be associated with zoonotic diseases which can have significant public health implications. The aims of the study were to examine the morphological data as well as the expression of the androgen receptor (AR) and anti-Müllerian hormone (AMH) in the male reproductive organs of H. larvatus from different areas of Thailand and at different sampling periods. Their testes were processed for histological investigation and immunohistochemistry for AR and AMH. The results showed differences among the various sampling areas and different sampling periods, which suggested seasonal breeding characteristics. The higher testicular morphometric data were observed in H. larvatus from the Dong Phayayen (DY) and Chiang Dao (CD) areas during June, while the size of seminiferous tubules decreased thereafter. High AR immunostaining was noticed when the testicular morphometric data were higher in DY bats during June. On the other hand, low AR was observed in bats during August and September, which was concomitant with the decreases in seminiferous tubule size and germinal epithelial height. The results suggest a potential correlation between AR immunostaining and the active phase of testicular functions in H. larvatus during June which may imply the involvement of AR with the enhancement of testicular activity. Conversely, the low expression of AR may contribute to the upregulation of AMH in the testes and may indicate lower testicular activity in H. larvatus in Thailand.

Expressions of cytochrome P450 aromatase and anti-Müllerian hormone in testes of fattening pigs by the timing of the first vaccination for immunocastration.

In practice, two injections of gonadotropin-releasing hormone (GnRH) vaccine are recommended for pig immunocastration for effective outcomes. The present study aimed to investigate the expressions of cytochrome P450 aromatase (P450arom ) and anti-Müllerian hormone (AMH) in testes, testicular length and testicular histomorphometry of the fattening pigs receiving the first injection of GnRH vaccine 6 weeks earlier than the standard protocol. Based on vaccination protocol, 24 pigs were equally divided into three groups: T1 was vaccinated at 15 and 19 weeks of age, T2 received vaccine at 9 and 19 weeks of age and C remained intact. P450arom and AMH expressions were analysed using immunohistochemistry and Western blot. The results revealed that testicular length was highest in C pigs, but not different between T1 and T2 groups (6.5 ± 0.2 versus 6.9 ± 0.3 cm, p = .538). Histomorphometry demonstrated that the height of spermatogenic epithelia, the diameter of seminiferous tubules and the number of seminiferous tubules between T1 and T2 groups were not different (p > .05). For P450arom , immunohistochemistry revealed that H-score of C group was significantly higher than that of both T1 and T2 groups. Western blot analysis showed that C group possessed the densest protein band. Moreover, H-score between T1 and T2 groups was not significantly different. Protein band intensity between both groups was not apparently different. As for AMH, C pigs had significantly lower H-score than both T1 and T2 pigs. Furthermore, T2 pigs possessed significantly higher H-score than T1 pigs. Western blot analysis showed that the most intense protein band was found in T2 group. In summary, GnRH vaccine affected testicular development and functions. The first injection could be performed either at 9 or 15 weeks of age since both protocols contributed to comparable results in aspect of testicular length, histomorphometry and expressions of P450arom and AMH.

Immunohistochemical study of Ki-67 protein, androgen receptor, and estrogen receptor beta in testicular tissues of male pigs immunocastrated with different times of GnRH vaccination.

This study aimed to investigate the immunoexpression of Ki-67 protein, androgen receptor (AR), and estrogen receptor beta (ERß) in testicular tissues of male pigs immunocastrated using GnRH vaccine (Improvac™, Zoetis Co., Ltd., Thailand) with different times. Totally, 30 male pigs were classified by castration protocol into three groups: T1 (n = 10) consisted of pigs immunocastrated at 14 and 18 weeks of age, T2 (n = 10) included pigs immunocastrated at 9 and 19 weeks of age, and C (n = 10) contained intact pigs. The results revealed that testicular length of pigs in C was longer than that of both T1 (8.1 ± 0.76 vs 6.5 ± 0.5 cm, p < 0.001) and T2 (8.1 ± 0.76 vs 6.9 ± 1.0, p = 0.007). Spearman correlation coefficients showed negative correlation between testicular length and H-score of AR (r = -0.38, p = 0.037), as well as positive correlation between testicular length and Ki-67 index (r = 0.602, p < 0.001). Generally, mean Ki-67 index and mean H-scores of AR and ERß of pigs in T1 were not different from those in T2 (p > 0.05). However, mean Ki-67 index and mean AR H-scores of T1 and T2 were significantly different from C group (p < 0.05). In summary, the immunocastration significantly affected testicular length, including expressions of Ki-67, AR, and ERß in pig testes. Moreover, the duration between two shots of GnRH vaccine could be extended from 4 to 10 weeks without difference in Ki-67 protein, AR, and ERß immunoexpressions.