Also, the chances that some of the L1 will develop into L2 cannot be modelled and will depend on various factors including the skill of the person conducting the experiment to obtain highly purified eggs, the faecal consistence (e.g. sheep vs. cattle, animal with and without diarrhoea), the epg, the host species and the parasite species. The gene discussed is EPGN; the disease is Diarrhea.