Expression of cyclooxygenase-2 in the endometrium of gilts with different stages of endometritis.

The present study determined the association among the expression of COX-2, stages of endometritis, and types and number of local immune cells infiltrating into the gilts' endometrium. The uterine tissues from 24 Landrace x Yorkshire gilts identified as acute endometritis (n = 7), chronic endometritis (n = 7), and normal endometrium (n = 10) were included. The tissues were prepared for both histological and immunohistochemical investigations. The immunoexpression of COX-2 in every layer of the gilts' endometria was appraised by avidin-biotin-peroxidase complex method via image analysis; and was reported as percentage of positive area and staining index. The results revealed that the immunoexpression of COX-2 was found only in the surface epithelial layer. The gilts with acute endometritis possessed higher both percentage of positive area (68.99% versus 4.50% and 3.43%, P < 0.001) and staining index (1.13 versus 0.05 and 0.04, P < 0.001) than those with chronic endometritis and normal endometrium, respectively. Positive correlations between the number of surface epithelial neutrophils and percentage of COX-2 positive area (r = 0.47, P = 0.022), as well as mean staining index (r = 0.44, P = 0.032) were observed. In conclusion, the immunoexpression of COX-2 was found strongest in the gilts with acute endometritis, meanwhile it was not different between those with chronic endometritis and normal endometrium. This suggested that the expression of COX-2 might be dependent not only on the infiltration of local immune cells in the endometrium, but also on the duration of exposure with inflammatory agents.

Seasonal variation in semen quality of swamp buffalo bulls (Bubalus bubalis) in Thailand.

AIM: To test the hypothesis that season affects the semen quality of swamp buffalo (Bubalus bubalis) bulls used for artificial insemination (AI) under tropical conditions in Thailand, as it does in Bos taurus and Bos indicus. METHODS: Clinical and andrological examinations, and monitoring of semen production and quality were carried out on five mature, healthy swamp buffalo AI bulls in Thailand from July 2004 to the end of June 2005. Sperm output, motility, morphology and plasma membrane integrity (PMI) were compared between three seasons of the year (rainy, i.e. July-October; winter, i.e. November-February; and summer, i.e. March-June) with distinct ambient temperature and humidity. RESULTS: All bulls were diagnosed as clinically healthy and with good libido throughout the study. Ejaculate volume, pH, sperm concentration, total sperm number and initial sperm motility did not differ between seasons, whereas PMI and the relative proportion of morphologically normal spermatozoa were highest in summer and lowest in winter (P<0.05). Buffalo age, week of collection and season influenced sperm morphology (P < 0.05-0.001). Among morphological abnormalities, only proportions of tail defects were affected by season, being highest in the rainy season and lowest in summer (P<0.001). In conclusion, climatic changes did not seem to largely affect semen sperm output or viability. Although the proportions of PMI and tail abnormalities were affected by season, they were always below what is considered unacceptable for AI bull sires. CONCLUSION: Seasonal changes did not appear to cause deleterious changes in sperm quality in swamp buffalo AI-sires in tropical Thailand.