Effects of a Bioactive Olive Pomace Extract From Olea Europea on Growth Performance, Gut Function, and Intestinal Microbiota in Broiler Chickens
The present study aims to investigate the effects of supplementing broiler diets with a bioactive olive pomace extract (OE) from Olea europaea on growth performance, digestibility, gut microbiota, bile acid composition, and immune response. To this end, three hundred and six 1-day-old broiler chickens (Ross 308) were housed in floor pens (6 pens/treatment, with 17 birds/pen). Animals were fed with a standard nonmedicated starter diet for 21 D, and from 22 to 42 D of age with their respective experimental diet: a negative control with no additives (Control), a positive control with 100 ppm of monensin (Monensin) and the basal diet supplemented with 750 ppm of an OE (Lucta S.A., Spain). Feed intake and growth rate were monitored weekly throughout the trial. From 21 to 42 D of age, no significant differences in feed intake were observed among dietary treatments; however, lower average daily gain and higher feed conversion ratio (P < 0.05) was observed in birds fed the Control compared to Monensin and OE groups. Performance of birds fed OE or Monensin was similar throughout the trial. The apparent ileal digestibility of crude protein was higher in birds fed Monensin than Control treatment (P < 0.05). No significant changes on bacterial composition at a family level were observed in the caeca of birds fed the experimental diets. Moreover, no significant differences on plasma and intestinal bile acid composition were observed among treatments. Birds fed the OE showed a significant decrease of IL-8 expression in the ileum (P < 0.05). Additionally, the expression of TGF-β4, and Bu-1 was significantly upregulated (P < 0.01) in broilers fed the OE and Monensin diets compared to those fed the Control. In conclusion, the inclusion of 750 ppm of a bioactive olive pomace extract from Olea europaea in broiler chicken diets improved animal growth likely as result of its anti-inflammatory properties.
Introduction Agricultural eco-innovation is based on circular economy and cradle to cradle concepts. This innovation concept aims at “zero waste” economy where new product and applications are created from raw material wastes(Mirabella et al., 2014). Spain is the largest olive oil(Olea europaea L.) producer worldwide with around 1.3 million tons that generates wastes such as olive pomace and leaves totaling annually more than 4 and 0.2 million tons, respectively (International Olive Council, 2017).One of the ways to take advantage of the olive oil industry wastes is its use in animal feed. It has been shown that the inclusion of up to 150 g/kg.
of byproducts such as olive pomace and cake in thefeed has no adverse effects in broiler performance (ElHachemi et al., 2007; Sayehban et al., 2016). Moreover,recent interest is being generated in the purification of the bioactive compounds (polyphenols, oleuropeo-side, flavonoid, and simple phenolics) from botanicals such as the olive by-products to enhance animal health and performance (Liehr et al., 2017; Leskovec et al.,2018). In a global strategy to reduce the use of drugs in animal production, plant extracts rich in bioactive compounds with anti-microbial, antioxidant, and anti-inflammatory properties are promising alternatives to antibiotics (Niewold, 2007,2014; Lillehoj et al., 2018).According to Niewold (2014) the positive effects of an-tibiotics on animal performance are directly related to their anti-inflammatory effects, which attenuate the intestinal inflammatory insults that take place under normal productive circumstances. Moreover, bioactive phytochemicals can stimulate innate immunity and might be an alternative to control coccidiosis in poultry(Lillehoj and Lee, 2012). In this regard, it has been recently suggested that olive pomace extracts might improve the intestinal health of calves and pigs (Liehret al., 2017; Morrison et al., 2017). Also, inclusion of an olive pomace bioactive extract in diets fed to sea bream showed a positive effect on growth performance by improving liver lipid metabolism and the intestinal innate immune function (Gisbert et al., 2017).
In addition, phenolic compounds extracted from olive leaves might be beneficial to broilers through their antimicrobial activity against intestinal pathogenic bacteria (Sarica and Ürkmez, 2016). Also, phenolic com-pounds can stimulate or inhibit digestive enzyme activities affecting nutrient digestibility in broilers (Brenesand Roura, 2010; Leskovec et al., 2018). The stimulation of other digestive secretions such as bile acidsby plant bioactives has been reported in rats (Plateland Srinivasan, 2000). Because of their potential use in poultry feeds there is a need to increase our knowledge on olive byproducts extracts and their effects on gut microbiota, nutrient digestibility, and bile acid metabolism.The present study aimed to investigate the effects of supplementing broiler diets with an olive pomace extract from Olea europaea on animal performance, nutrient digestibility, bile acid composition, gut microbiota, and immune function.
Agricultural eco-innovation is based on circular economy and cradle to cradle concepts. This innovative concept aims at “zero waste” economy or a sustainable production where new products and applications are created from by-products of agricultural wastes, namely olive pomace.
Extra Virgin Olive Oil is well known for its high antioxidant capacity, however, some phenols are lost in the waste during the olive oil extraction process. The question is, would there be potential benefits in recovering some of these lost phenols and would there be a potential to turn olive waste into several streams of products that could potentially open up new lines of profitability to the modern-day olive grove owner?
The latest study out of Spain aims to investigate the potential effects of supplementing meat chicken diets with an olive pomace extract in animal growth performance, nutrient digestibility, bile acid composition, gut microbiota, and immune function.
The study looked at the feeding trial which included:
- a negative control with no additives (Control)
- a positive control with 100 ppm of monensin (Monensin; Elanco Valquimia S.A.)
- the basal diet supplemented with 750 ppm of an olive extract (OE, Lucta S. A.; Spain) which consisted of an olive pomace extract standardized to contain a minimum of 10% total triterpenes and 2% polyphenols
Researchers noted “The inclusion of 750 ppm of an olive pomace extract containing a minimum of 10% total triterpenes and 2% polyphenols positively affects growth in broiler chickens. Among the possible mechanism of action studied so far in this work improvement in performance is likely related to the extract anti-inflammatory properties.”
This research is interesting because it potentially opens up a new market for chicken feed supplements made with olive pomace which could be a great addition to a value-added product, working towards more sustainable production and higher profits for producers outside of just producing olive oil.
Authors: J. Herrero-Encinas,∗ M. Blanch,† J. J. Pastor,† A. Mereu,†,1 I. R. Ipharraguerre,†,2 and D. Menoyo∗,3
- Departamento de Producción Agraria, Universidad Politécnica de Madrid, ETS Ingeniería Agronómica Alimentaria y de Biosistemas, 28040 Madrid, Barcelona, Spain;
- † Lucta S.A., Innovation Division, UAB Research Park, Edifici Eureka, 08193 Bellaterra, Barcelona, Spain
Read the full study at Poultry Science