Host endocrine interactions with nematode infections. I. Effects of sex, gonadectomy, and thyroidectomy on experimental infections in lambs

摘要: Male lambs were more susceptible to Oesophagostomum columbianum infections, harboring and larger worms producing fewer nodules than females. Gonadectomy removed these differences by increasing the susceptibility worm growth in female lamb. Thyroidectomy did not affect host resistance, as measured nodule numbers, but increase adult survival, particularly host. This was attributed decreased mucus production allowing survive thyroidectomized lambs. On first infection, many formed around larvae all lambs, rather secondary bacterial infections. The average daily egg output per 11,300. Worms from normal produced eggs other hosts. loss of worms, over period observation, giving an exaggerated result. Haemonchus contortus, a superficial migrator, show same responses endocrines O. columbianum. Thus conclusion reached that parasites which have extensive somatic migrations their life cycles are likely be affected hormone balance do this phase.