Coccidiose
In recent weeks, a lot of lovers mention that there is a lot of coccidiosis infections in their club. A lot of misunderstanding arises, is what I notice. Reason enough to pay some attention to this protozoal disease again.
Coccidiosis is an infection by a unicellular protozoan, with the name Emeria. Protozoa are single-celled organisms, which tricho and Hexamites belong to (if we talk about pigeons diseases). Mostly young birds are susceptible to infection with this parasite. Old birds can also contribute to many of these parasites without having any signs. The youngsters are more affected by this infection after weaning because their defense system is not yet sufficiently developed. If death occurs, it is mainly between the third and fourth month of life. With old birds the form may suffer when they got infected with coccidian, causing diminishing performance.
In Western Europe, especially the Eimeria labbeana and Eimeria columbarum are important. Worldwide, 9 species are described, but in addition to previously mentioned only Emeria Columba is further of importance. The Emeria labbeana is most common, in our area. So mainly a mixed infection of Emeria labbeana and Emeria columbarum is seen. Due to the mixing of the infections it would increase their pathogenicity. The degree of contamination varies from country to country. Contamination Levels of 15-55% to 80-93% for old birds and young birds are described
The Eimeria columbarum is slightly larger than the Eimeria labbeana. (or about 20 mu and 17 mu) The Emeriae living in the small intestine and in the front part of the hindgut of the pigeons. The prepatent periode, which is the period between infection and the appearance of 'eggs' in the manure is 8 days. These eggs are called oocysts. If these oocysts in the droppings appear they are not directly contagious for the pigeons. To be contagious for the pigeons they first have to undergo maturation. This maturation is called sporulation. During this maturation are then formed in each oocysts four sporocysts, each containing two sporozoites again. This maturation proceeds best under warmer and humid conditions and takes approx 1 to 4 days.
As soon as a pigeon picks up a sporulated oocyst and swallows, they will penetrate these sporozoites in the intestine from the oocyste come to the epithelial cells of the intestinal wall in order to greatly multiply there. In particular, the cells are attacked in the first two-thirds portion of the intestine by those sporozoites. These cells break open at any given time and are produced in the so-called cell, chizonts are free again in the intestine in order to penetrate into new cells. Three generations are formed. This way, a lot of cells die in the intestinal wall and in principle can cause great damage to the intestinal wall. This applies especially to youngsters who have built up little resistance against these parasites. At some point, the parasite is about to produce new oöcysten. After about 8 days they end up in the stool and the cycle starts again. Research showed that the infection moved about 10 cm each day intestine downstream. All this is a result of the ingress and exit of the intestinal epithelial cells.
Clinical signs
The symptoms of disease due to coccidiosis thus occurs mainly in young birds between 1 and 4 months of age. If death occurs this is usually between the third and fourth month of life. The signs may include emaciation and debilitation, dehydration and watery to mucous diarrhea, sometimes bloody diarrhea. The latter we do not see so often. The pathogenic capacity in adult pigeons are not so great. The most important symptom in adult birds is the influence on the flight performance and the shape of the pigeons. The diarrhea in youngsters is caused by a disturbance of the fluid balance by damage to the intestinal cells. The damage of the intestinal cells also allows that these nutrients cannot be picked up, what causes weight loss rapidly.
The presence of coccidia in the pigeons contributes to a reduction in the overall resistance, what cause that the animals are more susceptible to other infections. When you do section, it can be determined to a greater or lesser extent, redness of the intestine in which there is also inflammatory cells that can be determined microscopically. Many pigeons can carry the coccidiosis without having to show any significant clinical symptoms. When pigeons seem insatiable, eat much grit, but cannot get round, one may suspect an infection with coccidiosis even though there is not much shedding of oocysts found in research. The cause of this may as previously mentioned, are located in the not yet manifest are of the infection.
Immunitiy
The extent to which immunity is built up depends on the number of oocysts the pigeon is infected with. It, however, does not stop re-infection. However, it limits the production of the oocysts to reinfection. In adult animals it creates more of a balance between the degree of re-infection and immunity. In animals in which no treatment was instituted after reinfection, were a significantly fewer oocysts formed. Therefore one votes, when there is a case of mild infection of coccidiosis to leave it to prevent clinical outbreaks of coccidiosis.
A single infection with coccidia gives rise to a self-limiting infection with secretion for about 30 days. Or clinical signs occur, thus also depends on factors other than coccidiosis infection itself. (Young) pigeons can have a severe shedding of oocysts without significant clinical symptoms. On the other hand, excretion of oocysts indicate a weakening of the resistance of the pigeons. Once coccidia in the manure be demonstrated in clinical trials, it is therefore wise to look at the general health of the pigeons.
Diagnostics
The diagnosis of coccidiosis may be made by means of faecal examination. It should preferably be used from the sedimentation / flotation method in which (usually with a centrifuge), the oocysts are collected in the manure. The attentive reader may have already noticed that a significant infection of the intestine can take place in the manure without an already excretion of significant numbers of oocysts. Indeed, if the parasites are busy with the massive increase in the intestinal cells of these animals may have indeed been suffering without there being excretion in the manure. This may be because there is virtually no set coccidiosis in one manure sample while some days later can be determined that the birds can indeed have a very serious infection. In mortality among young birds can be made of staining of darmafstrijksels to determine the schizonts in the intestinal cells. In mortality among young birds can be made of staining of intestinal swabs to determine the schizonts in the intestinal cells.
Spread
The oocysts are very persistent, and can survive for long periods of time on the ground and in the manure (up to more than a year). Because of the wind oocysts can also be distributed and certainly pollution of drinking water with feces can contribute and can cause a spread of the infection. It would also carry on the ground or bottom of the travel baskets. We also see that pens which are faced with delivering a controlled environment contamination manure samples with significant numbers of oocysts. Often the roofs and gutters are massively infected. As long as this condition continues to exist, a solution of the problem on this lofts substantially is not to be realized.
I often hear those who say they do not understand that they have settled coccidiosis on their loft. Because their lofts are brushed and disinfected. Unfortunately, there are virtually no disinfectants that are effective against oocysts. Only with heat these oocysts are not really happy. Therefore if there is a heavy infestation, spray the floor with a spray bottle (to make sure it is moistened) and dry it up with a torch or heat gun. This way, one kills the present oocysts to best. It is not a luxury to pigeons that remained behind, to keep them isolated to determine through droppings or there is an infection with coccidiosis (and / or other infections like trichomoniasis and hexamitiasis).
Treatment
Light infections with coccidiosis (off season) do not have to be treated. Partly because reinfection is inevitable, but on the other hand because a slight infection gives rise to build a degree of immunity and infection is self-limiting. A too strong reduction of the number of oocysts may thus slow down the rate of the build-up of immunity through which the pigeons are just more prone to new (heavy) infections. However, it is important to apply a good sty hygiene in order to avoid build-up of a too heavy infection pressure. Taking into account the maturation time of the oocysts, it is in the presence of a hefty coccidiosis infection is important that the manure is removed daily and is secured as a dry floor in the loft.
If treatment is to be used it is necessary to look at the means that one wishes to use. Toltrazuril (Baycox) is in my opinion the most active agent and appears to contribute to the immunity against coccidiosis. Observation practice seems to indicate the shape of the pigeons temporarily deteriorates after a treatment with this drug. Traditionally, were used for the treatment of coccidiosis sulphonamides. There is now a strong resit variance of most coccidiose tribes against these agents. With the exception of sulfamethoxazole. We need to treat coccidiosis also note that many resources as Amprolium and Sulfonamides only be coccidiostatic. That means that they coccidia just slow down and not kill off. It reduced the infection pressure, but the infection with these agents do not really cleaned up. Toltrazuril and Clavuril latter may be, which in turn ensures that these agents are preferred. Both of these agents do not seem to inhibit the build-up of immunity. Indeed Toltrazuril appears to promote this right. Given that in the incubation stage (the period between infection and the onset of symptoms) no elimination of oëcysten need to act cannot guarantee a slight infection in research there's not more to it. Whether or not intervene then depend on the overall wellbeing of the dove and performance.
A natural agent on the basis of Usnea barbata in combination with some other herbs is found in practice to have an inhibiting effect on the excretion of oocysts, provided that it is administered at least twice a week. Curcuma has named to this as well. Unfortunately we cannot confirm this in experiments. Possibly this is because cucuma only works if it is accompanied by black pepper.
Good Luck!
Peter Boskamp
