Clinical, Endocrinological and Spermatological Studies after Endotoxin Injection in the Boar

Abstract

Summary Three adult boars were injected intravenously with endotoxin from Salmonella typhimurium. Blood plasma was analysed for the contents of 15‐ketodihydro‐PGF2α, LH and testosterone. Total amount of white blood cells and differential counts were determined in whole blood. Semen was examined for concentration, motility, volume and morphological appearance of the spermatozoa. The boars were slaughtered three months after the endotoxin injection and the testes were examined. The total number of white blood cells decreased and the levels of 15‐ketodihydro‐PGF2α rose immediately after the endotoxin administration. An initial increase in LH was seen in two out of the three boars. The increase in LH was followed by a testosterone increase in one boar and a testosterone decrease in the other. The third boar showed no initial increase in LH but an increase in testosterone. Semen examination demonstrated various morphological changes of the spermatozoa in all boars. The changes started to appear at about the same time after the endotoxin injection, but differed among the individuals. The examination of the testes depicted no changes from what is seen in normal animals. The present results indicate that the boar responds to endotoxin similar to what is seen in the ram. The endocrine changes, e. g. in LH and testosterone, are similar to those seen after termination of heat stress. The seminal changes indicate a disturbance located in the epididymis as well as a short‐term, mild degeneration in the seminiferous epithelium. Zusammenfassung Klinische, endokrinologische und spermatologische Untersuchungen nach Endotoxin‐Injektion beim Eber Drei adulten Ebern wurde Endotoxin von Salmonella typhimurium intravenös injiziert. Daraufhin wurde im Blutplasma der Gehalt an 15‐Ketodihydro‐PGF2α, LH und Testosteron bestimmt. Im Gesamtblut wurde die Gesamtzahl an Leukozyten sowie das Differentialblutbild ermittelt. Das Sperma wurde hinsichtlich der Zahl, der Motilität, des Volumens und der morphologischen Beschaffenheit der Spermien untersucht. Die Eber wurden 3 Monate nach der Endotoxin‐Injektion geschlachtet. Danach wurden die Hoden untersucht. Unmittelbar nach der Endotoxin‐Applikation nahm die Zahl der Leukozyten ab, der 15‐Ketodihydro‐PGF2α‐Gehalt stieg dagegen an. Bei zwei von drei Ebern wurde ein initialer Anstieg von Progesteron beobachtet. Auf einen Anstieg der LH‐Konzentration folgte bei einem Eber ein Anstieg der Testosteron‐Konzentration, beim zweiten ein Abfall. Der dritte Eber zeigte keinen initialen LH‐Anstieg, jedoch eine Zunahme des Testosterons. Die überprüfung des Spermas ergab bei allen Ebern verschiedene morphologische Veränderungen der Spermien. Die Veränderungen setzten zu etwa der gleichen Zeit nach der Endotoxin‐Injektion ein, differierten jedoch zwischen den einzelnen Tieren. Die Untersuchung der Hoden ergab keine Abweichung vom Normalzustand. Die Ergebnisse deuten darauf hin, daß der Eber ähnlich wie der Schafbock auf die Endotoxin‐Applikation reagiert. Die endokrinologischen Veränderungen, wie z. B. diejenig...

Alterations in testicular function after endotoxin injection in the boar

“…LH. The rise in LH is followed by an increase in testosterone levels (Wallgren, 1989). These changes in testosterone output are similar to those which develop after termination of heat stress (Larsson et al, 1983;Juniewicz & Johnson, 1984;Gaon & Liptrap, 1989;Malmgren, 1990).…”

“…The effect appears to be reversible; i.e. the number of abnormal spermatozoa in the ejaculate declines, and no morphological alterations are found in the testes 3 months after endotoxin administration (Wallgren, 1989).…”

“…Purified endotoxin from Salmonella typhimurium SH 4809 (Svenson & Lindberg, 1978;Lindberg et a!., 1983;Wallgren, 1989) was dissolved in 0.9% saline and administered to the boars through the jugular vein catheter in a single dose of 2.0 pglkg body weight.…”

“…Radioimmunoassays were used to determine the plasma concentrations of 15-keto-13, 14-dihydro-PGF2, (15ketodihydro-PGF,,), which is the main initial bloodplasma metabolite of prostaglandin Faa (Kindahl ef al., Wallgren et al, 1989), luteinizing hormone (LH) (Stupnicki & Madej, 1976;Madej et al, 1989;Wallgren, 1989) and testosterone (Oltner et al, 1979;Wallgren et al, 1989). For LH and testosterone, concentrations were considered to be increased if they exceeded the mean (+1 SD) levels from the control period.…”

The Immunophysiology of Male Reproduction

“…Acute systemic administration of LPS has been found to affect spermatogenesis in a number of species, resulting in apoptosis and progressive loss of spermatogenesis in the testis within days of administration, and reduced sperm concentration, motility, and viability for extended periods afterward. 322,499,688,693,694,696,733 In the adult rat, administration of a single dose of LPS across a very broad range of sublethal concentrations inhibited the formation of testicular interstitial fluid and suppressed intratesticular and circulating levels of testosterone, by inhibiting LH secretion from the anterior pituitary and reducing the capacity of the Leydig cells to produce testosterone in response to stimulation. 24,322,393,696 At the highest doses of LPS, this was followed by apoptosis of spermatogonia and spermatocytes, and premature release of spermatocytes and early round spermatids from the epithelium several days later.…”