Introduction: traditional coccidiostats and their limitations

Coccidiosis is a parasitic disease of importance in the poultry sector affecting farms from all around the world with an important economic impact [1,2]. For this reason, anticoccidial programs are systematically used to prevent this disease, which, even when subclinical, impairs performance and acts as a predisposing factor for other diseases.

Since the 50’s, synthetic and ionophore coccidiostats were added to the feed to prevent coccidiosis in broilers [3]. They act directly on the parasite to limit their reproductive cycle, so that coccidia can no longer damage the gut mucosa.

This direct action on coccidia has led to a rapid development of resistances [3], therefore, coccidiostats are frequently used in rotation and shuttle programs. Rotation programs changes to a different product or product combination after each flock, while shuttle programs alternate coccidiostats in the different production stages.

Besides the development of resistances, some coccidiostats have other disadvantages, such as the presence of residues in the meat and other products and, in the case of nicarbazin, hepatotocitity and decreased resistance of birds to heat stress.

In some regions, such as the European Union or the United States, these drugs were already limited and there is a limited number of products available and less options for rotation and shuttle programs. Many important poultry producers from other countries may find it difficult to internationally export meat, and/or need to make changes to meet the new market trends: part of the consumers would rather eat “green” products, which means that they would rather eat meat from animals raised with less antibiotics or in free-range systems.

Currently used anticoccidial programs and related regulations

In Central America and Ecuador, coccidiostats are allowed in poultry farms. Ecuadorian regulations describe them as pharmacologic additives that require medical prescription [4,5]. With these measures, the authorities have a greater control on the use of these products trying to limit, at least partly, the development of new resistances.

Despite these drugs are still available, their future use is uncertain, since they have a decreased efficacy due to the development of resistance, which causes problems in farms related to clinical and subclinical coccidiosis. For this reason, some poultry producers in the region are already looking for novel alternatives to naturally prevent coccidiosis without negative consequences.

Poultry producers need to get used to new solutions to control the infestation with simpler programs (no rotation or shuttle combinations), without resistances, while increasing the added value in the market. This way, farms will be ready for any changes towards a more restrictive regulation in the near future.

Intestinal optimizer pronutrients as an effective tool

The raising market trend towards the consumption of natural food products, the loss of efficacy of the traditional solutions and the legal limitations call for a novel solution to replace coccidiostats: intestinal optimizer pronutrients.

Pronutrients are active molecules from plant extracts that stimulate cell physiology to optimize the organs and, this way, improve gut welfare, among other functions [6,7]. Pronutrients that act as intestinal optimizers stimulate the immune local system of the intestines so that animal cells are ready to eliminate coccidia.

This mechanism of action, based on immune stimulation rather than on a direct effect on the parasite, prevents the development of resistances. It was described in molecular and cellular assays where these pronutrients increased interleukin IL-1, IL-12 and IL-18 expression in polymorphonuclear cells isolated from the gut, which are essential elements of anti-coccidia reactions in birds.

When birds receive intestinal optimizers in the feed or the drinking water, their local immune system will be active at physiological levels and capable of eliminating coccidia to prevent the damage they produce.

This effect has been observer in many field trials following the scientific methodology that were conducted in different parts of the world in experimental and commercial poultry farms. They show that intestinal optimizers help animals to defend themselves from coccidiosis.

In a trial in broilers, pronutrients were more effective under different environmental conditions (wet and dry season) for a long period of time than a traditional anticoccidial program [8].

In another trial, conducted in El Salvador, intestinal optimziers were included in the feed continuously and reduced mortality by 20,93% and improved uniformity by 5 points in week 16 of age, compared to a vaccine against coccidiosis [9].

In addition, pronutrients do not require withdrawal period. They act physiologically, do not cause negative effects and are completely safe. They meet the new consumers’ requirements, and their availability is guaranteed in the future, since they are completely natural and already registered in countries with limitations such as the European Union and the United States.

Conclusions

Traditional products to prevent coccidiosis have important disadvantages, such as the development of resistances, which lead to the loss of efficacy and their limitation and/or ban in several countries.

Coccidiostats are still available in Central America and Ecuador, but some producers are already replacing them by intestinal optimizer pronutrients since traditional drugs lost their efficacy and there is a trend in the market to choose natural products.

Pronutriens are an effective and completely natural tool to boost the animal immune system, so that it can eliminate coccidia. They physiologically stimulate local immune cells in the gut and, since they do not directly affect the parasites, they do not create resistances.

Their efficacy has been broadly proved in vitro and in the field in different trials that show their long-term efficacy under different conditions in broilers, pullets, layers, and breeders. They were proved more efficient than traditional coccidiostats (+64 points in the efficiency index) and cocci vaccines (-21% mortality and +5 uniformity points).

Intestinal optimizers are pronutrients developed and patented by Biovet, S.A. marketed as Alquernat Zycox, available in premix and liquid presentations to be included in the feed or the drinking water.

Bibliography:

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2. Miguel JA, Asenjo B, Ciria J, Del Cacho E, Calvo JL. Comparison of control methods for coccidiosis in native Spanish “Castellana Negra” chickens. Spanish J Agric Res. 2008;6(4):531–6.
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8. Estudio de la eficacia de pronutrientes optimizadores intestinales para controlar la aparición de coccidiosis en broilers [Internet]. 2018. Disponible en: https://www.veterinariadigital.com/post_blog/estudio-de-la-eficacia-de-pronutrientes-optimizadores-intestinales-para-controlar-la-aparicion-de-coccidiosis-en-broilers/
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