I preventatively treat my cattle, sheep, and goats for coccidiosis, also known as bloody scours. This means I add a coccidiostat such as amprolium (CORID is my preferred brand) to their drinking water without them even showing signs of the illness. While I do vaccinate and don't give antibiotics for weight gain or without illness present, my one exception is that I treat preventively for this protozoal infection. It's mortality rate can be high among lambs and kids, and calves are miserable. Amprolium is also very specific in its action.
Coccidia (protozoa) are naturally occurring in the environment and adult animal immune systems usually combat them without problem. When there is a upward trend in temperatures and snow starts to melt, there seems to be an explosion of these protozoa in the environment. Younger animals (or weak elderly) do not have as robust of an immune system and can not fend off the protozoal attack. I have seen one of my healthy young bucks show early symptoms, so I view them all as at risk.
What happens? Calves from the prior spring are most likely affected and all lambs and kids from that year. They feel miserable, stop eating, stop playing, develop diarrhea (often bloody), and fail to thrive. This is enough to kill about 2/3rds of a year's lambs or kids with aggressive treatment saving the other third. Treating these smaller young once they are sick is much less successful than treating calves. Calves are a bit more robust and rarely die from it, but it can scar their digestive tract and cause them to lose weight and then later not gain it as well. I would suspect they would be more susceptible to repeat infections, but I'm not sure about this.
My understanding is this disease can also affect chickens and other poultry, humans, and dogs - each specie vulnerable to its own variety of parasite. I don't know about horses. I've never treated them for it and mine haven't contracted it even when foals.
There is a treatment I find similar to what works for treating cold sores. For those who get them, it is possible to feel them before blisters form - the feeling often described and an itch or a little painful. Or, if one or two little blisters emerge, it can prevent the blister from getting bigger. (Once there, it doesn't heal faster, though.) At this stage, taking a dose of lysine (AKA L-lysine, 500-1,000 mg once or twice) stops the outbreak. Lysine is an essential amino acid that the cells in your body cannot make and it has preferential treatment with regards to storage within the cells. The herpes virus that causes cold sores needs arginine to replicate, which is not as highly favored by the cells. So, when a person takes lysine, the cells dump the arginine, the herpes doesn't have what it needs to replicate, and it goes back into hibernation. Amprolium is to coccidiosis what lysine is to herpes - a fatal interruption ... more or less.
Amprolium is my treatment of choice and works by mimicking thiamin (vitamin B1), which the parasite needs. They take up the amprolium instead of thiamin, but it doesn't work the same way. The coccidia end up deficient in thiamin and die. I have had one bout in my calves with clinical signs. Poor little calves looked miserable. I put the amprolium in their water and made sure there weren't other sources of water (blocked access to a stream catching run-off that was probably contaminated). On the second day I didn't notice new bloody diarrhea, but they didn't act like they felt better yet. The third day, they were eating again, though not a lot. They were also drinking more. They continued to improve after that. The smallest and youngest of the bunch recovered last.
If you treat with amprolium, treat the entire herd. This will reduce the overall coccidia population. I give it preventatively at our January thaw, the winter's final thaw, and before and during lamb and kid weaning. I know of small goat dairies that have had devastating losses and now treat regularly. I hope to avoid that happening on my farm.
If you have questions about this before buying our meat or milk in terms of whether this is organic, please feel free to research it. My understanding is beef producers participating in antibiotic-free natural beef production can use amprolium if they follow the label. Regardless, I use it because it prevents a miserable illness for my calves and that likely will kill my lambs and kids because of our soggy springs. Amprolium isn't used to unnaturally fatten animals and doesn't upset the healthy microbial populations in their digestive tract. I've seen very positive result from using it.
Wife to Brandon, mother to Tess and Liam, farmer, entrepreneur, cook & baker, nurse, and accountant who loves to try new things, travel, and work toward greater self-reliance.