Control coccidia and necrotic enteritis outbreaks

Phytobiotics help control outbreaks of coccidiosis and necrotic enteritis

Fernando Aguado, Doctor of Veterinary Medicine, Technical Specialist for Eastern Europe and Central Asia, Liptosa (Lipidos Toledo S.A.)

Coccidiosis is one of the most widespread protozoan diseases in poultry. Despite well-known treatment protocols, there is no “magic pill” or vaccine that completely solves the problem. The absence of a single solution pushes veterinarians toward an analytical approach to studying coccidiosis and revisiting standard control practices.

A dangerous pairing

It is generally believed that broilers and layers are most often affected by coccidiosis. However, this pathogen also impacts other species, including ruminants.

Avian coccidiosis (family Eimeria) is caused by ingestion of sporulated oocysts, leading to clinical or subclinical disease and characterized by diarrhea.

Sick birds consume less feed, which worsens their condition. Disruption of intercellular junctions leads to aggravated diarrhea. As a result, birds lose body weight because they cannot absorb nutrients or maintain adequate amino acid levels.

Another manifestation of coccidiosis is reduced zootechnical performance. The gradual destruction of intestinal epithelial cells causes malabsorption syndrome, which leads to performance decline. A drop in albumen production can also lead to a temporary cessation of egg laying.

It should be noted that Eimeria affects both the small and large intestines. In ruminants, however, the infection acts more aggressively in deeper tissue layers, leading to enteritis.

Necrotic enteritis is usually associated with coccidiosis. It affects a large portion of the intestine, gradually migrating from the small intestine to the ceca.

Given the multifactorial nature of this disease, one trigger for necrotic enteritis can be nutritional factors—specifically, a high protein level or poorly digestible protein sources.

Particle size and feed composition also play a role. Wheat, rye, and barley have higher levels of non-starch polysaccharides. If the small intestine is compromised, nutrients are not absorbed, and the pathogen can utilize these polysaccharides for further expansion.

Stress factors add to the nutritional aspects—changes in feeding regime, deteriorating environmental conditions, or increased stocking density. Other diseases, such as Gumboro, also contribute to immune suppression.

These factors provoke the development of coccidiosis, which in turn is the main driver leading to necrotic enteritis.

Proper control

The pharmaceutical market offers many products capable of treating coccidiosis and necrotic enteritis. Common active substances in coccidiostats include diclazuril, decoquinate, halofuginone, monensin, and others. It is not recommended to use a single coccidiostat for a long time. To avoid resistance, different actives should be used across the broiler cycle for each feeding phase. It is also very important to carry out chemical sanitation and vaccinate once a year.

A highly effective strategy is to alternate coccidiostats with live attenuated vaccines against parasites. Concurrent use of live vaccines and anticoccidial drugs is not recommended, so as not to reduce the effectiveness of either and to increase the birds’ resistance to disease.

Necrotic enteritis is treated with available antibiotics such as penicillin. Dead birds should be removed immediately to prevent the spread of infection through cannibalism.

It is also essential to maintain a healthy balance of microflora—this supports overall resistance and promotes bacterial competitive exclusion.

Plant-based support

Despite preventive measures aimed at avoiding resistance, Eimeria species have a high capacity to develop drug tolerance. Eleven coccidiostats permitted in the EU have been deemed ineffective due to parasite adaptation. Consequently, more European poultry and livestock producers are seeking safer alternatives to traditional treatments. With growing emphasis on animal welfare, the market needs a new scenario in which phytobiotics play an important role in combating coccidiosis.

A program that employs coccidiostats, live attenuated vaccines, and special nutrients against coccidiosis can currently be considered optimal. It slows the development of resistance to coccidiostats and minimizes side effects while maintaining a balanced microflora that prevents pathogen proliferation.

The effectiveness of plant-derived components has been demonstrated in live-animal trials. As with any therapeutic, their interaction with coccidia depends on the parasite’s life-cycle stage. Essential oils, in particular, act on sporogony and on the merogony phase of the cycle.

Antibiotic-free strategies

In recent years, the global market has shown interest in feeding strategies that incorporate phytobiotics, organic acids, prebiotics and probiotics, enzymes, and more.

Phytogenics help reduce sporogony and pathogenic bacterial growth, which in turn lowers the number of oocysts and stimulates the immune system. Consequently, the chances of infecting other animals are minimized.

Phytobiotics also improve the animal’s overall condition and promote the restoration of intestinal cells and permeability that were disrupted by diarrhea.

There are many plant extracts that can be relied upon, including carvacrol, thymol, lycin, eugenol, and others. They reduce oocyst counts, interact with sporozoites, influence gut microbiota structure, and modulate bacterial proliferation.

Thus, plant extracts exhibit selective antimicrobial action—suppressing harmful bacteria while preserving beneficial microbiota. They also stimulate digestion.

Organic acids primarily affect bacterial DNA structure and replication, as well as glucose metabolism. Beyond limiting pathogen growth, they improve intestinal morphology, support enterocytes, increase villus height, and reduce crypt depth.

They can penetrate a damaged membrane and will not access the cell if the membrane is intact.

By creating micropores in bacterial walls, organic acids together with phytobiotics enter the cell; therefore, the effect of this combination is significantly enhanced.

Saponins and tannins improve microbiota balance. As components of phytobiotics, they possess specific chemical properties and, to varying degrees, act on bacterial membranes, strengthening the immune response.

Therefore, after studying the positive effects of phytobiotics, the Spanish company Liptosa developed products and vaccines that provide natural support within the overall program.

In particular, COCCILIP, available as a powder or liquid, can be incorporated into feed. It effectively combats coccidiosis and necrotic enteritis. In its liquid form, the product can be used for rapid response during coccidiosis outbreaks or as a preventive measure during periods of elevated risk.

The natural solutions used in the product reduce the risk of bacterial resistance, so there is no withdrawal syndrome.