Diarrhoea in poultry is a problem that can arise even in the best-managed flocks, affecting bird condition and production performance. In many cases, pharmacological treatment is entirely justified — a rapid response limits the spread of the problem and minimises losses. However, not every case of diarrhoea immediately calls for chemotherapeutic agents. It is worth considering natural gastrointestinal support, especially when clinical signs are mild or stem from transient environmental factors such as a feed change, high ambient temperature, or transport-related stress.

One of the most promising solutions lies in plant-derived phytoncides — among them tannins, naturally occurring bioactive compounds with potent astringent and antibacterial properties. Their action supports the condition of the intestinal mucosa.

How do tannins affect gastrointestinal health in poultry?

Reducing diarrhoea and protecting the intestinal tract

Tannins reduce excessive water loss, resulting in firmer faecal consistency and a reduction in wet litter — a key factor affecting animal welfare. Through their astringent properties, they support the integrity of the intestinal mucosa and help limit the further development of inflammatory conditions.

Antibacterial and antiviral activity

Certain tannins — such as gallic acid — can penetrate bacterial cells and disrupt their metabolism, as well as inhibit the growth of pathogens including Clostridium spp., Streptococcus spp., and Staphylococcus spp. Research also indicates that tannins may limit the replication of viruses responsible for gastrointestinal infections.

Supporting beneficial gut microbiota

Tannins, particularly proanthocyanidins (procyanidins), act as prebiotics — promoting the growth of beneficial bacteria such as Lactobacillus and Bifidobacterium, which helps restore the natural intestinal microbiome following periods of stress or antibiotic therapy.

Antioxidant properties

Intestinal inflammation is frequently associated with oxidative stress. Tannins act as natural antioxidants, neutralising free radicals and limiting damage to cell membranes within gastrointestinal structures.

Improved digestion and nutrient absorption

Through their ability to form complexes with proteins, tannins regulate digestive processes and improve amino acid absorption. They also influence the production of volatile fatty acids (VFAs), which play a key role in the body’s energy metabolism.

Improved feed palatability

The use of tannins has a positive effect on appetite — birds may respond better to tannin-enriched feeds, which encourages greater feed intake and more efficient utilisation of its nutritional components.

How and when to use tannins in poultry production?

Tannins work best as a supportive measure at the first signs of diarrhoea, or as part of a preventive programme during periods of heightened risk of digestive disturbances. They can be administered both as a feed additive and as a water-soluble preparation, with the dose adjusted to the current needs of the flock.

Their properties make them a valuable tool in modern poultry production, helping to reduce the need for antibiotic use and supporting gastrointestinal integrity. They can also be used as adjunctive treatment in cases of coccidiosis and bacterial diarrhoea caused by anaerobic bacteria of the genus Clostridium spp.

Given their versatile range of action, it is worth considering their routine use — both as a preventive measure and as support during episodes of gastrointestinal dysfunction.

Biolax plus — effective gastrointestinal protection

One of the best preparations for supporting gastrointestinal health in poultry is BIOLAX PLUS — a specialist herbal blend rich in tannins derived from pedunculate oak (Quercus robur) and horse chestnut (Aesculus hippocastanum). Thanks to its high content of bioactive substances, it supports the organism during episodes of digestive upset and diarrhoea, acting both symptomatically and on the underlying cause. An example of its application is presented in the clinical case description below.

ClLINICAL CASE No. 1

Flock

Heavy commercial turkeys BIG 6, 9 weeks of age

Clinical signs

The farm reported a sudden change in the appearance and consistency of droppings, with increased liquid content in the excreta and deterioration of litter quality. In addition to the loss of normal consistency, the droppings had an abnormal appearance — either foamy and light yellow in colour (Photo 1), or glossy and dark brown (Photo 2). Flock mortality remained within physiological limits.

Photo 1. Foamy, orange droppings

Photo 2. Glossy, dark brown droppings

Diagnosis: Bacterial diarrhoea

Treatment protocol — 5 days:
Biolax Plus: 500 ml / 1,000 L drinking water, for 12 hours
Clostric: 500 ml / 1,000 L drinking water, for the following 12 hours

Outcomes

Following completion of treatment, an improvement in litter quality and normalisation of droppings were observed — physiological excreta consistency restored (Photo 3).

Photo 3. Physiological droppings

BIOLAX PLUS helps address the wet litter problem and can be used in situations where antibiotic therapy is contraindicated — for example, in laying hens or in birds approaching slaughter. The table included with the product provides detailed usage guidelines for Biolax Plus. Its astringent and detoxifying action supports the body’s natural defence mechanisms, while also stimulating the secretion of digestive enzymes and improving nutrient absorption.

The use of natural tannins in poultry nutrition is an effective way to improve flock health and reduce the risk of digestive disturbances. With BIOLAX PLUS, animal welfare can be managed safely and efficiently — reducing the need for pharmacological interventions and improving overall production outcomes.

For more information about Biolax Plus or other products in Biopoint’s portfolio, please contact our Export Managers.