Rosin_Resin acids

Several peer-reviewed publications have demonstrated the positive performance effects of Progres® Liquid, Hankkija’s unique tall oil fatty acid (TOFA)-based feed ingredient for broiler chickens. The product contains 9% of natural coniferous resin acids dissolved into linoleic acid, oleic acid and other free fatty acids of pine and spruce trees.

The fatty acids of Progres® are valuable to the birds as a source of energy, but the true benefit of the product as a performance enhancer for broiler chickens stems from the resin acids. The natural mixture of abietic acid, dehydroabietic acid, palustric acid, and other resin acids has previously been shown to reduce the inflammation-associated collagen breakdown in the jejunum and ileum of broiler chickens. More specifically, resin acids inhibit the expression and activity of matrix metalloproteinase (MMP)-7 aka matrilysin, and other MMPs which degrade structural proteins of intestinal mucosa, such as collagen and tight junction proteins, during inflammation.

A new open access article, published on October 25th 2021 in a special issue of Poultry Feeding and Gut Health in the peer-reviewed journal Animals, demonstrates improved broiler performance by dietary coniferous resin acids without the free fatty acids of TOFA. The paper presents three 35-day broiler experiments which were conducted by Professor Krzysztof Lipiński and his research team at the University of Warmia and Mazury in Olsztyn, Poland. A total of 1680 Ross 308 broilers were used in these experiments.

In all the three experiments, the resin acid -fed treatments showed significantly higher bird body weight on day 35 than the control treatments. Furthermore, European Efficiency Index (EEI) and litter quality were improved by the resin acid amendment in all experiments.

The EEI is a measure of the efficiency of broiler production, taking into account the length of fattening, feed intake, final bodyweight, and the survival rate of the birds. Improvement in this index indicates a more efficient broiler production when resin acids are added to the diets.

The dryer litter as a response to dietary resin acids suggest reduced gut leakage and diarrhea, and therefore a better intestinal condition in the resin acid -fed groups. This observation is in line with previous resin acid and TOFA studies in broiler chickens and turkeys.

In conclusion, amending broiler chicken diets with a natural mixture of coniferous resin acids improved the growth performance of broiler chickens, reduced litter moisture and resulted in a more efficient broiler production in three separate broiler experiments.

Please see the article at for more details.


Lipiński, Vuorenmaa, MazurKuśnirek, Sartowska-Żygowska, Kettunen (2021) Dietary resin acid concentrate improved performance of broiler chickens and litter quality in three experiments. Animals 11: 3045. https://