Review/Oorsig Volume 22, Issue 04 - Page 25

Volume 22 • Issue 04 • 2018 Crypto may have been present for some time but perhaps never received the attention that it receives now. The past 3 years I have paid specific attention to the diagnosis of Crypto with smears, histopath, bacteriology and antigen ID with Vetdiagnostix. The correlation between the different diagnostic techniques was high with Crypto being present with E coli & Salmonella (I suspect secondary) in 91% of the cases. E coli was involved on its own was in very few cases and we had it identified and had a vaccine made. affected. That same pen/ run may not have any problems for the following batches or year. One of the questions has been: Why the sudden increase in Cryptosporidium? A group of us at Onderstepoort investigated all calf diarrhoea cases, during the early 1990’s, as calf diarrhoea was also common then. Jaco van der Lugt [Pathologist] co-ordinated it, Truuske Gerdes looked for viruses, Laura Lopez for protozoa and I did the bacteria, and we asked others, e.g. toxicologist, if there was an indication of anything else. Most of the cases during that time were due to viruses. Effective vaccines for the viruses have since become available. There were very few cases due to Cryptosporidium at that time. LW - 26 May 2018 MH- 27 Nov 2017 What has changed in the meantime? There has been a worldwide increase in cases in man, and these are related to water and food contamination, raw sewage in water sources and HIV. Chlorination of water does not kill Cryptosporidium. Better diagnostic sensitivity of tests, as well as more awareness of Cryptosporidium being a possible diagnosis. Change in weather patterns resulting in both floods [which spread contamination] and drought [which concentrates the cysts]. Cryptosporidium is very resistant in the environment. It is resistant to chlorination of water. There are many different species of Cryptosporidium, and many of them infect multiple host species. It is also very infective, as only a few cysts can cause disease, and many millions of cysts are shed during the acute phase. Cysts are also shed for many months after recovery. AO - 27 Nov 2017 Just to confirm when we observe Crypto in the ostrich industry – 80% cases during mid to late summer. Any rain or leaking water sources. Pica/ vices by chicks. High water consumption causes high frequency and volume of urination = increase risk of soil pica or vice. Any small stressor triggers it. You can have 4 batches next to each other with only one being Jo'D - 25 May 2018 Is both diseases a problem on the same farm(s)? Or is a farm hammered by either Crypto or E.coli? Which wildlife species show clinical disease with Crypto? And which have shown mortalities? Management/production system on these farms? I am not aware of any Crypto outbreaks this side of the Magaliesberg but E.coli seems to be a problem all over. We see Crypto and E coli in both calves and lambs. Sometimes both, sometimes one of the 2. Confirmed by Vetdiagnostix, IDEXX and Vetpath over the last few years. We are in the Eastern Free State, on the border of Lesotho. Intensive lambing systems and extensive systems, summer and winter. (Also see Rick Last under Dx) CONCURRENT INFECTIONS EdP - 27 Nov 2017 The commercial E. coli vaccine unfortunately did not work. We found that quite long ago that the results with the commercial vaccine was very poor and then initiated the process of having an autogenous vaccine produced. The results that we see lately are promising. The vaccine has been produced for many clients. The vaccine is not a silver bullet as it seems that the crypto is still the instigator and many other factors also play a role in the outcome of your treatment regime. PR - 27 Nov 2017 More related to vaccination against E.coli. How much of an effect would a non-autogenous (commercial) vaccine have and how are the commercial E.coli vaccines strains chosen? And also more focused on sheep. MH - 27 Nov 2017 E. coli is a normal commensal of the intestine, and it is also found in the environment. Only a very few strains possess virulence factors, and they can cause disease. The virulence factors are mainly of two kinds: attachment to the intestinal wall and toxins. A variety of virulence factors have been found and are being found by scientists, as this is a dynamic area of research. The attachment factors and toxins can be general, 25