ALTERATIONS IN TESTICULAR FUNCTION AFTER ENDOTOXIN INJECTION IN THE BOAR

Twelve mature boars were injected intravenously with endotoxin from Salmonella typhimurium. Blood plasma was analysed for 15-ketodihydro-PGF2alpha, LH and testosterone. The boars were castrated at various times after endotoxin administration and the testes examined by light and electron microscopy. The levels of 15-ketodihydro-PGF2alpha and LH rose immediately after endotoxin injection followed by an increase in testosterone levels, and in five boars a second increase in LH levels was observed. Morphological examination of the testes revealed infiltration of polymorphonuclear neutrophils (PMN) into the testicular interstitium. The Leydig and myoid cells showed morphological changes. Alterations were also present in the seminiferous epithelium among Sertoli cells, spermatocytes and spermatids. The results indicate that endotoxins can exert a negative effect on testicular function in the boar. Except for the initial increase in LH levels, which is not clearly understood, the hormonal changes are thought to be mediated by alterations in Leydig cell function. The alterations further support previous findings in the boar, and indicate that there is short-term, moderate damage to the seminiferous epithelium following endotoxin injection.