Wednesday, July 23, 2014
Coccidiosis - An Unfortunate but Common Problem
This season, I have had an overwhelming amount of questions about Coccidiosis, cocci as it's commonly called. I also spoke with our state veterinarian and several trusted breeder friends who agreed that this was the worst season in years of cocci outbreaks. There have been rampant strains, likely due to the wet winter and hot, humid summer. I wrote this blog post to provide a one-stop shop of information that breaks it down to the basics of what it is, how to do your best to avoid an outbreak, and treatment. It is likely that all chicken keepers, breeders, hobbyists who do this for long enough, will eventually deal with a bout of cocci. It's always best to be prepared.
Coccidiosis is a common but serious problem for all flock keepers, from small backyard hobbyists to large production hatcheries. All - let me repeat that - ALL chickens carry some cocci. Controlling the amount of oocysts they carry is the key to preventing outbreaks.
Coccidiosis is not a bacteria or virus, it is caused by a protozoa that can survive for months. It's a common protozoa in the genera Eimeria. There are two types of coccidiosis, cecal and intestinal. There are several strains and some are worse than others. Coccidiosis defies good sanitation practices unfortunately and thrives in warm, moist environments. There aren't any disinfectants effective at destroying oocysts. Only drought or freezing temperatures will eliminate them from the environment. Wet winters creates longer exposures as chickens huddle up and spend so much time in the coops and brood houses, creating more feces and foraging in them, thus creating more outbreaks.
The oocysts are ingested and absorbed into the gut lining causing damage to the intestinal tissue. They're very prolific parasites, producing 100s in a very short time with a life cycle of 4-7 days.
Most oocysts cause inflammation in the gut and diarrhea with or without blood. The parasite grows in the host and multiplies, usually in the lining of the gut, although certain species will grow in other organs. Oocysts are developed in the bird, passed via their feces and then in the right conditions will spread and infect the others. The population builds to dangerous levels over time. Once the coccidiosis has damaged the gut, secondary infections are common because it is easier for bacteria to colonize in damaged cells. Coccidiosis is species specific.
Overcrowding and high density, litter bedding, and damp, humid conditions, will allow a build-up of the parasite causing an overload. Lower levels may not affect healthy adults with a developed immunity but can cause problems in chicks and adults with poor body condition and growth.
Ideally, chicks will develop immunity to cocci as they're gradually exposed to it with age. 3-8 week old chicks are the must susceptible as well as those weakened by poor nutrition or disease. It's suggested that medicated feed is provided until they're 16 weeks old, especially in high level soils. The medicated feed does not kill the oocysts but helps in keeping the level of oocysts present maintained as the chicks develop natural immunity to it. Keeping dry, clean pens and avoiding overcrowding will help prevent an overload. It can be tricky, you want to allow chicks to develop immunity while not causing disease. This requires them to pick up just enough oocysts to stimulate their immune system while not picking up so much that it is overwhelmed and they become diseased.
Obviously, based on this, the best way to take care problems from Coccidiosis is to avoid overexposure, preventing an outbreak in the first place. While not all outbreaks can be avoided, there are steps you can take as a responsible flock owner to head most of them off. You know the old saying, "An ounce of Prevention..."
Proper brooder/run and coop management is really the key to control. The goal in prevention is to reduce the number of oocysts in the environment. This keeps the infection at a minimum until immunity can be established.
Keep the litter dry and clean. Managing their brooder properly will help avoid the amount of oocysts eaten. Good sanitation and litter management can keep you ahead of the parasites. Be extra cautious with the areas around waterers. Chicks love to kick pine, poo, and food into the waterers. These areas will stay wet creating an area for the cocci to thrive. Clear the wet bedding around your waterers and replace it often.
Avoid overcrowding- again to prevent the ingestion of too many oocysts. A general rule of thumb is 1 square foot/chick, this provides them with sufficient space.
Provide adequate feeders and waterers and keep feeders full as well. Many times this is overlooked. 4 feeders and 4 waterers per 100 chicks is adequate if kept full and clean. If the feeders and waterers become empty and/or contaminated, this encourages the chicks to forage in their litter, again, ingesting more of the oocysts and creating an overload. Pay attention to clearing poo from the feeders and waterers. They are chickens, they are going to contaminate their feeders - like my little friend here clearly shows. This one was determined to always eat from inside our feeders. When he was in the brooder it was a constant battle to keep it clean but it has to be done.
Provide adequate ventilation to allow the excess ammonia and humidity to ecscape. A heat source with adequate insulation can prevent condensation build up. Ventilation is so important! Draft free but well ventilated should be your motto in housing.
Outside access can actually limit the build up of oocysts because it provides natural forage time and therefore they are less likely to forage around the brooder eating droppings. However, outside control of the buildup can be difficult in wet, humid conditions. Especially in the late Spring, Summer, and early Fall which can lead to outbreaks. Many breeders will begin by slowly adding small clumps of grass in their brooder for the chicks to forage in, peck at, and play on to begin developing thier immunity to their soil early. There's a fine line with this, you definitely want to provide them with gradual exposure but not overload.
The most common transfer to chicks is by human carrier. This means on your shoes, your hands, your clothing. When handling chicks under 8 weeks, care for them FIRST and/or change your clothing and wash your hands.
Never mix chicks of different ages and from different hatches. Biosecurity 101! Coccidiosis or not, this is a rule to live by.
If symptoms are seen, you have a very small window to treat successfully. Begin treatment immediately. This part relies on you, the flock owner, to be an experienced and keen observer. The key really is early detection. Monitor feed intake, decreased appetite may be the first sign in the early stages. If you are small scale, this may allow you to keep ahead of the parasites. The photo below is a fecal sample of a very advanced stage of cocci. If they all left these signs right away, we wouldn't worry but it's not this obvious early on when you want to catch it. Do not wait to see this before taking action. Know your flock and pay attention to them.
Which leads me to symptoms. Some clinical signs of coccidiosis are the following:
- droopiness & listlessness
-loss of appetite
-pale combs and wattles
-huddling together or acting chilled
-blood and/or mucous in the feces (blood is not always present. Do not assume it is not cocci just because you do not see blood)
-diarrhea (sometimes seen in the form of "pasty butt")
-death if not treated early enough
It can be confused with necrotic enteritis but diagnosis outside of symptoms and clinical signs can be made inexpensively with a fecal sample with coccidiosis screening. Here in Virginia, the state vet will do a sample for you for only $10. If you're outside Virginia, call your State Veterinarian for pricing. Many general veterinary offices will also do a fecal test for you at minimal costs. I've heard from $8-10 in my area. The only other way to obtain diagnosis is through a necropsy. If you lose a chick before noticing, you can keep it's body cool in the refrigerator (not freezer) and contact your state vet for a necropsy. Here in Virginia, there is a state budget that allows most to be performed at no cost.
If you've had an outbreak, I strongly recommend that you take regular fecal samples to the state veterinary office or your vet to monitor and prevent future outbreaks. We try to monitor our birds with these quarterly. It also helps ensure the prevention and management of other internal parasites so for the small fee, it's a win-win. If you have access to a microscope, it's easy to perform your own testing. You only need to purchase a fecal sample solution. There's an interesting article here about making your own solution.
Feed only scrambled egg with vitamins & probiotics mixed in. Try to avoid corn products as they increase the body temperature.
As their appetite increases, return to their chick feed with probiotics and vitamins mixed in.
You can make a smoothie for them consisting of chick feed, water, probiotic powder, and raw egg. Feed this through a syringe in little bits every few hours if they're not eating on their own.
Give 2.5 cc Amprolium 9.6% liquid (either Corid or Amprol)/ quart for 10 days. If using the gallon waterers, 2 tsp/gallon. Amprolium is an anti-coccidial drug that kills the cocci. There isn't any meat nor egg withdrawal and it is a time-tested treatment that has proved to be effective in intestinal and caecal cocci.
It's important to add the treatment to the water because thier feed intake suffers first.
Watch for hydration and make sure they stay hydrated.
Add 1/4 tsp of Vitamin E to their water or orally. Vitamin E has been show to shorten the course of the outbreak
Clean feeders and waterers with EVERY refill- yes- daily!
Change their bedding daily
No Apple Cider Vinegar (ACV) during treatment. I know, I know, every forum and facebook group you visit will tell you to add ACV first thing. Do NOT! ACV will aggravate their stomach lining if they're sick and it also cancels out the benefits of the probiotics due to the PH level.
Treat the entire brooder/flock
Follow up this treatment with vitamins and probiotics in their water for one week.
**ALWAYS use Amprolium based medications PRIOR to using any Sulfa drugs. Sulfa can aggravate certain species of coccidiosis and make the condition worse. Some species of cocci can cause intestinal bleeding and the use of Sulfa will contribute to that bleeding before helping. I personally avoid Sulfa drugs in our flock but if you feel you MUST use it- I highly recommend doing so under the supervision of an avian veterinarian and AFTER trying the Amprolium based medication first. **
If your chicks have no symptoms, a general, a natural treatment for stronger immune systems in chicks are probiotics and vitamins. We use the Vita Pro B vitamin/probiotic mix offered by Peter Brown at First State Veterinary Supply.
A plan using the medications for preventing and building immunity to coccidiosis follows. I have not personally used this treatment although it was recommended by a veterinarian and another chicken expert so it does come from trusted sources. This must be started before the chicks are ten days old. Keep in mind that this disease kills chicks very quickly and will run through an entire brooder before you can begin treatment if you're not careful and observant of your flock.
Amprol/Corid powder- 1 tsp/gallon in water for 7 days
Skip 21 days
Sulfa 1/2 oz/gallon in water for 5 days
Skip 21 days
Begin again and continue until the birds are 6 months old or pullets are laying. REMEMBER-You MUST use the Amprolium based medication first.
Another option is to vaccinate your chicks for Coccidiosis. Doc Brown sells these vaccinations here. Vaccinating against coccidiosis does not guarantee you a cocci free flock as it can't vaccinate against all strains, however, it does offer protection against the major strains giving you much more protection than you have without it.
Don't be too hard on yourself! Do not judge others simply because they have had a coccidiosis outbreak. As I said in the beginning of this post, it is not always within the breeder's control. What is in our control is doing our very best to protect our flock and avoid outbreaks buy practicing proper prevention, biosecurity, and good farm management. Know your flock and carefully observe them so when an outbreak occurs, you can isolate and treat it.