RESUMEN
Melissa officinalis (lemon balm) has a long history of being used in traditional medicine for the treatment of gastrointestinal tract disorders in human thanks to its spasmolytic and stress reducing effects. These pharmacological properties have been confirmed in laboratory animals. Unfortunately, in the case of veterinary medicine, the effect of lemon balm on gut contractility has been never subjected to a detailed investigation. On the other hand, there is urgent need of new drugs that could be safely used in animals for both, causative and symptomatic treatment. In broiler chicken, one of the major health concerns includes gastrointestinal disorders with gut hypermotility. Thus, it is crucial to verify the potential utility of Melissa officinalis extract in gastrointestinal dysmotilities. The aim of the study was to analyze the effect of lemon balm extract and some of its active ingredients on chicken intestine motility. The study was performed on isolated proximal and distal jejunum preparations collected from broiler chicken which underwent routine slaughter procedure. The effect of lemon balm and 3 phenolic acids (rosmarinic, chlorogenic, and lithospermic) was verified under isometric conditions, toward spontaneous and acetylcholine (ACh)-induced smooth muscle activity. Surprisingly, M. officinalis turned out to be rather a myocontractile agent as it increased ACh-provoked contractility of proximal and distal jejunum strips and also intensified the spontaneous activity of distal jejunum. Only in the case of proximal intestine lemon balm extract diminished the force of spontaneous motoric activity up to approx. Sixty-seven percent of the control conditions. None of the tested phenolic acids displayed analog effect with the whole plant extract. In fact in the case of ACh-induced contractility, the acids had the opposite, that is, myorelaxant, effect than the extract, with a small exception of lithospermic acid in distal jejunum. Thus, it is impossible to assign one or more individual constituents to the effect of the whole Melissa officinalis extract. The obtained results do not support the use of lemon balm extract in broiler diseases which are accompanied by gut motility disturbances, including diarrhea.
RESUMEN
The objective of this study was to investigate the effect and composition of a standardized natural citrus extract (SNCE) on both broiler chickens' growth performances and intestinal microbiota. A total of 930 one-day-old males were randomly assigned to three dietary treatments: a control treatment (CTL) in which broiler chickens were fed with a standard diet and two citrus treatments in which broiler chickens were fed with the same standard diet supplemented with 250 ppm and 2,500 ppm of SNCE, respectively. Each dietary treatment was composed of 10 experimental units (pen) of 31 broiler chickens each. Growth performances such as feed consumption, body weight, and feed conversion ratio (FCR) were recorded weekly until day 42. Litter quality was also weekly recorded while mortality was daily recorded. One broiler chicken was randomly selected from each pen (10 chickens/group) and ceca samples were collected for microbiota analysis at day 7 and 42. Chromatographic methods were used to determine molecules that enter into the composition of the SNCE. Results from the characterization of SNCE allowed to identify pectic oligosaccharides (POS) as a major component of the SNCE. In addition, 35 secondary metabolites, including eriocitrin, hesperidin, and naringin, were identified. The experiment performed on broiler chickens showed that the final body weight of broiler chickens fed diets supplemented with SNCE was higher than those fed the CTL diets (P < 0.01). Broiler cecal microbiota was impacted by age (P < 0.01) but not by the dietary supplementation of SNCE. Results indicate that SNCE allowed enhancing chickens' performances without any modulation of the cecal microbiota of broiler chickens. The characterization of SNCE allowed to identify compounds such as eriocitrin, naringin, hesperidin, and POS. Thus, opening new horizons for a better understanding of the observed effect on broiler chickens' growth performances.
Citrus extracts are increasingly being used in animal nutrition to enhance animal growth performances. Most of the available studies indicate an effect of these extracts on microbiota. However, citrus extracts can vary a lot. Indeed, the composition of citrus extract depends on parameters such as the citrus species, the extraction methods, and the inclusion rate. This variation is very important to take into consideration before using a citrus extract. The objective here was to evaluate a commercially available standardized natural citrus extract in terms of composition and effect on broiler chickens' performances and microbiota. Results showed that standardized natural citrus extract positively affects the final weight of broilers, but no effect was observed on chickens' caecal microbiota. The characterization of the standardized natural citrus extract reveals pectic oligosaccharides as major compounds as well as 35 others molecules. Most of these compounds are well described for their beneficial effect on animals' performances and health. In conclusion, the standardized natural citrus extract showed beneficial effects on broilers' performances. These effects are not correlated with broilers microbiota modulation and may be explained by the composition of the product.