effect of rosemary leaves powder and essential oil on performance, microbial population, intestinal morphology and meat quality in meat quails

introduction: one of the aim of poultryscientist is to reduce cost feed along with increase in performance and improve in carcass characteristic poultry (1). in recent years, interest in use medicinal plants as feed additive to replace antibiotic growth promotor has increased. the plant additive through effect on the microbial flora of the gastro intestinal tract and the control pathogens improved growth. components of essential oil have shown biological properties such as antioxidant and antimicrobial activity (34). in vitro, antimicrobial and antioxidant activity of essential oils from labiate family such as oregano and rosemary has been reported (25). rosemary is shrub sustainable belong to the family lamiaceae. the active ingredients of the plant are essential oil, tannins and bitter substances. the most importance compounds include cineole, camphor and bornyl acetate (28). in this study, effect of rosemary powder and essential oil on performance and meat quality in meat quails were investigated. material and method: in these study 300 japanese quailchicks were tested in completely randomized design with 5 treatment and 4 replicate per treatment from 1 to 35 days. in each experimental unit 15 quail chicks were reared in the same environmental condition. five experimental diets (treatments) were included: 1) control diet without any additive, 2) control diet plus 50 mg/ kg essential oil of rosemary, 3) control diet plus 100 mg/ kg essential oil of rosemary, 4) control diet plus 0.25 % rosemary powder, 5) control diet plus 0.5 % rosemary powder. extraction and separation of essential oil rosemary leaves was performed by gas chromatography and mass spectrometry. body weight and feed intake were measured weekly and mortality was recorded daily and then used to calculate the performance parameters. at the end of experiment (35 days), one bird from each replicate was killed to determine the concentration of malonedialdehyde (mad), ph, water holding capacity, dripping loss and cooking loss in thigh meat. data from the experiment were analyzed in a completely randomized design by sas software and comparison means were performed with using of duncan’s multiple range tests at 5% level. result and discussion: introduction one of the aim of poultry scientist is to reduce cost feed along with increase in performance and improve in carcass characteristic poultry (1). in recent years, interest in use medicinal plants as feed additive to replace antibiotic growth promotor has increased. the plant additive through effect on the microbial flora of the gastro intestinal tract and the control pathogens improved growth. components of essential oil have shown biological properties such as antioxidant and antimicrobial activity (42). in vitro, antimicrobial and antioxidant activity of essential oils from labiate family such as oregano and rosemary has been reported (8,29). rosemary is shrub sustainable belong to the family lamiaceae. the active ingredients of the plant are essential oil, tannins and bitter substances. the most importance compounds include cineole, camphor and bornyl acetate (36). in this study, effect of rosemary powder and essential oil on performance and meat quality in meat quails were investigated. material and method in this study 300 japanese quail chicks were used in a completely randomized design with 5 treatment and 4 replicate in each treatment from 1 to 35 days. in each experimental unit 15 quail chicks were reared in the same environmental condition. five experimental diets (treatments) included: 1) control diet without any additive, 2) control diet plus 50 mg/ kg essential oil of rosemary, 3) control diet plus 100 mg/ kg essential oil of rosemary, 4) control diet plus 2.5 g/kg rosemary powder, 5) control diet plus 5 g/kg rosemary powder. extraction and separation of essential oil rosemary leaves was performed by gas chromatography and mass spectrometry. body weight and feed intake were measured weekly and mortality was recorded daily and then used to calculate the performance parameters. at the 35 days, 4 bird from each treatment were selected to investigate morphology of villus and determinate microbial colonies was killed and the samples were taken. also at the end of experiment (35 days), one bird from each replicate was killed to determine the concentration of malonedialdehyde (mad), ph, water holding capacity, dripping loss and cooking loss in thigh meat. data from the experiment were analyzed in a completely randomized design by sas software and comparison means were performed with using of duncan’s multiple range tests at 0.05 level. result and discussion the result showed that at 0 to 21 day of age quails fed with rosemary powder improved body weight gain compared to control group. at the 21 to 35 days and whole rearing period, body weight gain was not affected by experimental treatment. in other study, supplementation of the basal diet broiler chicks with avilamycin or essential oil improved body weight, body weight gain and feed conversion ratio compared with the control group (29). in addition, adding 250 mg/ kg rosemary essential oil to quails diet improved the body weight than the control group (11). in contrast, no effect plant additive on body weight gain and performance has been reported in the result hernandez et al (19) and amad et al (3). feed intake and feed conversion ratio in quails fed with rosemary essential oil and powder was not affected by experimental treatment. adding 0.5 and 1 % rosemary powder in the broiler diet did not affect body weight gain and feed intake (15). in addition, in the study jang et al (23), there was no different in growth performance, feed intake and feed conversion rate in broiler fed with herbal essential oil. the effects of plant extracts on performance are obviously variable. this may be attributable to differences in composition of the various phytogenic additives and the concentration of the active substances and their biological activity, respectively. in addition, the response of chickens to a phytogenic feed additive might be affected by other factors, such as the diet type, animal age, environmental factors and product quality (33). fed with powder and essential oil to increase the papulation lactobacillus and coliforms were reduced. in addition the villus length and width in treatments receiving rosemary increase and the crypt depth were reduced. the antibacterial activity of medicinal herbs is related with concentration and composition essential oil in them (5). it seems that the active compounds of rosemary improve the bird performance by decreasing the small intestine thickness and also harmful microbial population (32). use of rosemary powder decreased thiobarbituric acid compare with control group. the highest ph was observed in treatment fed with 100 mg/kg rosemary essential oil. water holding capacity increased in treatments receiving rosemary (expect 50 mg/kg essential oil) compared with control group. the use different levels of rosemary powder in quail diet were reduced cooking loss percent. dripping loss was not affected by experimental treatments. poultry meat is particularly prone to oxidative deterioration due to its high concentration of poly unsaturated fatty acid (28). yesilbag et al (44) reported that quails fed with diet containing rosemary decreased thiobarbituric acid in breast meat. in experiment mirshekar et at (31), fed of various plant extracts (green tea, rosemary, aktynh) in broiler diets had no effect on ph and water hold capacity, but the thiobarbituric acid was lower in this group. rosemary with antioxidant properties prevent oxidation meat and consequently increase the water holding capacity. conclusion in the present study, the using of rosemary in quail diet improved the performance during 0-21days, and also improved the quality meat parameters in the whole period of study. meat quality: rosemary powder decreased thiobarbituric acid compare with control group. the highest ph was observed in treatment fed with 100 mg/kg rosemary essential oil. water holding capacity was increased in treatments receiving rosemary (expect 50 mg/kg essential oil) compared with control group. the use different levels of rosemary powder in quail diet were reduced cooking loss percent. dripping loss was not affected by experimental treatments. poultry meat is particularly prone to oxidative deterioration due to its high concentration of poly unsaturated fatty acid (24).yesilbag et al (36) reported that quails fed with diet containing rosemary decreased thiobarbituric acid in breast meat. in experiment mirshekaret at (26), fed of various plant extracts (green tea, rosemary, aktynh) in broiler diets had no effect on ph and water hold capacity, but the thiobarbituric acid was lower in this group. rosemary with antioxidant properties prevent oxidation meat and consequently increase the water holding capacity. conclusion: in the present experiment, however the uses of rosemary in diet (except at the 0 to 21 days of age) didnot affect the performance parameter, but was improved meat quality. thus the use of rosemary as a natural antioxidant to improve the quality meat can be recommended.