Thanks for the information. Calf Span boluses contain sulfamethazine which is an older antibiotic labeled for E.coli scours. It does have some activity against coccidiosis. The COrid (amprolium) is a liquid that is specifically for coccidiosis and has worked for me better than sulfamethazine. There could be more things going on here,let me give you some more thoughts. Calves that scour long enough can get streaks of blood from irritation and damage to the intestines. Coccidiosis causes blood more regularly than other causes of scours. Without diagnostic tests to see what the actual cause of the scours is, we have to consider the possibility and treat for all causes.
Causes of scours are: 1. Bacteria (e.coli, Salmonella, Clostridium) treatment is antibiotics. Micotil will help with this. The 1 shot the calf had lasts 3 days. You may need to give another shot of micotil. Some bacteria are resistant to some antibiotics. It is possible that you have bacteria that needs a different antibiotic. Draxxin is a newer medicine and lasts 5-7 days. It is a good one for bacterial scours.
2. Coccidiosis -treatment Sulfamethazine once a day for 5 days in a row. or Corid (amprolium) once a day for 5 days in a row. Treating for 5 days in a row is the key
3. Viruses (rota, corona, esp.) There isn't any specific treatments for viruses.
4. Parasites- You ave used ivermectin and that should take care of that.
5.Mixed infections-You can have coccidiosis, bacteria and viruses at the same time. The only thing to do in this case is treat for coccidiosis and bacteria and the calf's immune system will have to handle the viruses on its own.
With this said I would give another antibiotic shot, preferably Draxxin, but micotil may be OK. Treat for coccidiosis for 5 days in a row, preferably with corid,but calf span may be OK.Last but not lease you must maintain hydration and electrolyte levels while the medicine is working. I recommend an electrolyte that has a thickening agent like SKy High Energy by Schuyler Labs or Resorb. If you don't have access to these , any electrolyte solution will help. Give the calf the electrolytes as per label directions twice a day with no milk. The electrolytes have enough energy to keep the calf going and milk can irritate a scour. Once the calf has quit scouring you can go back to milk. There are a lot of issues that can complicate scours in a calf and sometimes the damage to the intestines is too much to survive and you can lose the calf in spite of treatment. I hope this has helped. Good Luck.
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