Claudio Forte

Effects of oregano (Origanum vulgareL.) and rosemary (Rosmarinus officinalis L.) aqueous extracts on broiler performance, immune function and intestinal microbial population

ABSTRACT A 57-day study was performed to determine the effects of two aqueous extracts (AEs) on broiler performance, immune function and intestinal microflora. Four groups of 75 one-day-old female broilers (Ross308) received one of the following treatments: (1) a standard commercial feed (C); (2) C supplemented with 2 g/kg rosemary AE (R); (3) C supplemented with 2 g/kg oregano AE (O); (4) C supplemented with 1 g/kg oregano AE + 1 g/kg rosemary AE (OR). Individual body weight, average daily gain, average daily feed intake and feed conversion efficiency were determined at 1, 11, 22, 36 and 57 days. Sample collections for IgG titration and intestinal microflora examination were performed at 22 and 57 days. The addition of oregano AE alone or in combination with rosemary AEs improved body weight up to 36 days of age (P < .01). A time effect was recorded for total serum IgG in all groups (P < .001) and the percentage increase of the value was positively (P < .05) influenced by the AE supplementation. Lactobacilli raised (P < .001) in ileum and cecum of all groups supplemented with AEs. Staphylococcus spp. population was constantly lower in both intestinal tracts of the AE supplemented groups. On the basis of our results, AEs could improve broiler performance and immune function and contribute to a balanced gut microflora, essential for the digestion process and protection against enteropathogenic organisms.

Dietary integration with oregano (Origanum vulgare L.) essential oil improves growth rate and oxidative status in outdoor‐reared, but not indoor‐reared, pigs

The effects of a diet supplemented with oregano essential oil on performance, oxidative status, pork quality traits and sensorial properties were evaluated. In two studies, 72 pigs in indoor or outdoor conditions were assigned to either a control diet or an identical diet supplemented with 0.2% oregano essential oil. Pigs reared outdoor showed lower live weight, average daily gain and average gain:feed ratio compared to indoor pigs. The oregano supplementation improved the growth performance of the outdoor- but not the indoor-reared animals. The serum oxidative status was influenced by the diet. A higher oxidative stability was observed in the oregano-supplemented groups. As for the rearing conditions, the data suggest that after an initial adapting period, the free-range farming systems could be better tolerated by pigs. Meat derived from pigs reared outdoor showed higher pH and a* values. Lightness was influenced by both the diet and the rearing conditions. The control group reared indoor showed shear force values higher than both supplemented groups, while no differences were detected with the control group reared outdoor. In the consumer test performed under blind conditions, the oregano groups achieved higher consistency scores compared with the control. Under informed conditions, the meat derived from the oregano-supplemented pigs reared outdoor received the highest scores for consistency and overall liking regardless of the rearing system. The same result for the overall liking score was obtained in the expectation test. The data obtained showed that dietary oregano essential oil can be effective in reducing performance losses due to the outdoor-rearing system, increasing the oxidative status of the animal and oxidative stability of the meat, without modifying the meat quality traits and improving consumer perceptions of the meat quality.

Dietary effects of oregano (Origanum vulgaris L.) plant or sweet chestnut (Castanea sativa Mill.) wood extracts on microbiological, chemical-physical characteristics and lipid oxidation of cooked ham during storage

The aim of this study was to evaluate the dietary effect of feeding pigs with diets enriched with sweet chestnut wood (Castanea sativa Mill.) or oregano (Origanum vulgaris L.) extract on the microbiological and chemical characteristics of cooked pork ham. Three groups of 10 pigs were fed with a control diet (CTRL), with the CTRL diet enriched with 0.2% of oregano extract (OR) and with the CTRL diet enriched with 0.2% of sweet chestnut wood extract (SCW), respectively. Six cooked hams per group were produced, sliced and packaged under a modified atmosphere (N2:CO2=80:20) and stored at refrigeration temperature (4±1°C). Three packages per cooked ham were sampled for analyses at three different storage times (0, 10 and 20 days). At day 0 time, antioxidant capacity of the products (ORACFL assay) and chemical composition were performed. At each sampling time, from all the samples the following analyses were performed: total microbial count (TMC), lactic acid bacteria count (LAB), Enterobacteriaceae count, Listeria monocytogenes, pH value, colour coordinates (L*, a*, b*), total basic volatile nitrogen (TBVN) and thiobarbituric reactive substances (TBARs) determinations. No differences in TMC, LAB and Enterobacteriaceae count, pH, TBVN, chemical composition and L* values were registered between the three groups at all the sampling times considered. No Listeria monocytogenes was detected in the samples tested. Significant differences were registered for ORACFL at 0 days, a* and b* values and TBARs value at 10 and 20 days of storage, with higher values for ORACFL, a* and b* values and lower values for TBARs in SCW and OR than CTRL. No antimicrobial effect could be recorded for OR and SCW but a higher oxidative stability, also highlighted by the colour maintenance, was observed in both OR and SCW.

Dietary oregano (Origanum vulgare L.) aqueous extract improves oxidative stability and consumer acceptance of meat enriched with CLA and n-3 PUFA in broilers.

&NA; The effect of a dietary oregano aqueous extract on meat fatty acid profile, quality, and consumer acceptance in chickens fed a diet rich in polyunsaturated fatty acids (PUFA) was evaluated in 3 consecutive trials. For each trial, 171 day‐old Ross 308 chicks were randomly divided in replicates of 19 birds each and assigned to one of 3 experimental diets: 1) basal control diet, 2) basal diet supplemented with 0.2 g/kg of oregano aqueous extract, and 3) basal diet supplemented with 150 ppm of vitamin E (as positive control). To better analyze the antioxidant activity of both oregano and vitamin E, all the experimental diets were enriched with a fatty acid supplement consisting in a mixture of PUFA at the same dose (1.16 %) in both starter and finisher feeds. Oregano supplementation positively influenced (P < 0.05) broiler live performance. No differences were observed in physicochemical or proximal composition or in total fatty acid composition of breast meat. Dietary oregano influenced meat composition in terms of total phenolic content, antioxidant capacity, and thiobarbituric acid‐reactive substances, improving meat resistance to oxidation, compared to both other groups. During consumer tests, meat from the 3 dietary groups obtained the same liking score in a blind session. Under informed condition, consumer perception was positively influenced by labeling for all the considered attributes. Furthermore, consumers showed a higher expectation for meat derived from chickens fed the oregano extract when compared to that deriving from the other 2 groups. Results obtained in the present study allow stating that using oregano aqueous extract in diets enriched with PUFA can represent a valid solution to increase live weight of chickens, improve resistance to oxidation of meat, and positively influence consumer perception of poultry meat.

Microbiological, chemical-physical and sensory characteristics of Fabriano salami from pigs fed Oregano vulgaris extract

This study aimed at evaluating the effect of Oregano vulgaris extract supplementation of heavy pig diet on the microbiological, chemical-physical and sensory characteristics of Fabriano salami. Fabriano salamis were produced processing meat derived from pigs belonging to two dietary groups of 16 pigs each: CTRL group fed a commercial pelleted feed, and OR group fed the CTRL diet integrated with 0.2% of oregano extract. Ten salamis per group were collected at 0, 7, 20 and 45 days of ripening and analysed for total viable count, enumeration of Enterobacteriaceae, Enterococcus spp, coagulase negative and positive staphylococci, Lactobacillus spp., Lactococcus spp., presence of Salmonella spp. and Listeria monocytogens, pH, water activity (aw) and colour (CIE L*a*b* colour system). At the end of the ripening (day 45) chemical composition (AOAC, 1990), total antioxidant capacity (ORACFL), thiobarbituric reactive substances (TBARS), total phenolic content (TPC) (Folin-Ciocalteu method) and consumer tests were performed. The integration of oregano extract in pig diets did not interfere with the microbial evolution, chemical composition, pH and aw. After 20 days of ripening the OR salami were redder then CTRL samples, which were also yellower at the end of ripening. Furthermore, the diet has significantly improved the oxidative status, the polyphenolic content and antioxidant power in OR salami. The consumers gave a higher score to OR salami in informed condition.