CHANGES IN BROILER CHICKENS FOLLOWING SUPPLEMENTATION WITH CINNAMOMUM ZEYLANICUM

A study was conducted to investigate the effects of different doses of Cinnamomum zeylanicum in diet on blood biochemistry of broiler chickens. Thirty two, 1-d old male broiler chickens of a commercial strain ROSS 308 were distributed into groups of 8 birds in each one. The chicks received the diets from the day of hatching to 38 d of age. The four types of diets included basal diets for chicks (HYD 01, HYD 02 and HYD 03) supplemented by 0%, 0.1%, 0.05 and 0.025% cinnamon (Cinnamomi aetheroleum of Cinnamomum zeylanicum, Calendula a.s., Nová L'ubovña, Slovakia). Continuous lighting and water and feed ad libitum were provided throughout the trial. The addition of cinnamon to the diets caused a significantly lower plasma glucose level and the effects of cinnamon on plasma glucose levels tended to be dose-dependent. Dietary intake of 0.05 and 0.025% cinnamon reduced serum ALT and plasma potassium levels. Ingestion of cinnamon, however, resulted in no significant changes in circulating calcium, albumin, triglycerides, free glycerol and cholesterol levels. It was concluded that cinnamon could be used not only for flavor and taste in food preparation but it had an additional role in glucose metabolism in broiler chickens.

strains of bacteria (Gustafson and Bowen, 1997); antibiotic use has been banned in the European Union since January 2006 (Regulation 1831/2003/EC).
Many herbs and plant extracts have antimicrobial activities and antioxidant properties which make them useful as natural additives in animal feeds.Si et al. (2006) reported that cinnamon exerts antimicrobial activity against Salmonella serotype Typhimurium DT 104 of swine in vitro study.These findings are in agreement with reports of Prabuseenivasan et al. (2006).They reported that cinnamon clove, geranium, lemon, orange and rosemary oils exhibited a significant antibacterial effect against both gram-negative and gram-positive bacteria in vitro.The antioxidant effect of aromatic plants is due to the presence of hydroxyl groups in their phenolic compounds (Shahidi et al., 1992).
Most essential oils are classified as Generally Recognized as Safe (GRAS), and have been approved for food and beverage consumption by the US Food and Drug Administration.
Plant extracts (anise oil, cinnamon oil, garlic oil) may allow the manipulation of rumen microbial fermentation by decreasing total volatile fatty acid concentration and reducting ammonia N concentration (Busquet et al., 2006).Essential oils derived from sage, rosemary, thyme and other herbs inhibit osteoclast activity and in vitro leading to an increase in bone density (Putnam et al., 2006).
Recently, it was reported that some essential oils such as cinnamon have the potential to favorably influence the insulin system and beneficial effects on blood glucose and lipid metabolism of people with type 2 diabetes (Khan et al., 2003).
There is a dearth of literature regarding the effects of cinnamon on blood biochemistry of broiler chickens.
The objectives of the current study were, therefore, to investigate the effects of different doses of Cinnamomum zeylanicum in diet on blood biochemistry of broiler chickens.

Animals and diets
Thirty two 1-d old male broiler chicks of a commercial strain (ROSS 308, Párovské háje, Slovakia) were randomly distributed into groups of 8 birds in each one.The birds were kept on the floor for the course of the study.Chicks were initially kept at 31 o C; then the temperature was gradually lowered to a final temperature of 28 o C. Continuous lighting and water and feed ad libitum were provided throughout the experiment.
All experimental procedures with animals were in accordance with European Guidelines for Care and Use of Animals for Research Purpose and they were approved by a local ethic committee.
The chicks received the diets from the day of hatching to 38 d of age.The basal diets were formulated to meet or exceed all nutritional requirements of starter, grower and finisher (Table 1).The four types of diets included basal diets for chicks (HYD 01, HYD 02 and HYD 03) supplemented by 0%, 0.1%, 0.05% and Materials and methods / Materijal i metode rada 0.025% cinnamon (Cinnamomi aetheroleum of Cinnamomum zeylanicum, Calendula a.s., Nová L'ubovña, Slovakia), certificate of quality No 610.

Sampling and analyses
At the age of 38 days, chickens from each group were anaesthetized with intraperitoneal injection of xylazine (Rometar 2%, SPOFA, Czech Republic) and ketamine (Narkamon 5%, Czech Republic) at doses 0.6 and 0.7 ml.kg -1 of body weight, respectively.After laparotomy, blood was collected into heparinized tubes by intracardial punction and centrifuged for plasma specimens at 1180 g for 10 min.Samples of plasma for analysis were frozen and stored at -65 o C. Serum was stored at +2 to +8 o C.

Statistical analysis
Results are presented as mean ± S.E.M. Statistical significance was performed by a one-way analysis of variance (ANOVA).
Addition of cinnamon to the diets caused a significantly lower plasma glucose level and the effects of cinnamon on plasma glucose levels tended to be dose-dependent (Table 2).Dietary intake of 0.05% and 0.025% cinnamon reduced serum alanine aminotransferase activity and plasma potassium levels.Ingestion of cinnamon resulted in no significant changes in circulating calcium, albumin, triglycerides, free glycerol and cholesterol levels (Tables 1).
Dietary addition of cinnamon (0.1, 0.05 and 0.025%) to broiler chickens for 38 days resulted in a decreased plasma glucose level in a dose-dependent manner.
C. zeylanicum has been shown to be generally safe when ingested and to have many pharmacological properties, such as antioxidant activity, antiinflammatory and antimicrobial effects (Mancini-Filho et al., 1998; Lopez et al., 2005).
Methylhydroxychalcone polymer (MHCP) in C. zeylanicum was found to be an effective mimetic of insulin (Jarvill-Taylor et al., 2001).MHCP demonstrated in vitro activation of glycogen synthase and inhibition of glycogen synthase kinase-3b as well as insulin receptor phosphorylation homologous to the effects of insulin in 3T3-L1 adipocytes.Later it was found that cinnamaldehyde in C. zeylanicum was effective in decreasing plasma glucose concentration, glycosylated hemoglobin, serum total cholesterol, triglyceride level and in addition markedly increased plasma insulin, hepatic glycogen and HDL cholesterol level to streptozotocin-induced male diabetic Wistar rats (Subash Babu et al., 2007).
Effect of C. zeylanicum on blood glucose and insulin sensitivity was evaluated in several animal studies.Kannappan et al. (2006) reported that dietary cinnamon extract improved glucose tolerance and prevented the hyperlipidemia observed in fructosefed rats.Similar results were observed in db/db mice.Kim et al. (2006) suggested that dietary cinnamon extract had a regulatory role in blood glucose levels and lipids and it could also exert a blood glucose suppressing effect by improving insulin 71 Vet.glasnik 62 (1-2) 67 -75 (2008) Zita Faixová and [.Faix: Blood chemistry changes in broiler chickens following supplementation with Cinnamomum zeylanicum Discussion / Diskusija sensitivity or slowing absorption of carbohydrates in the small intestine.Similarly Talpur et al. (2005) observed that combinations of essential oils such as fenugreek, cinnamon, cumin, oregano lowered circulatory glucose levels and systolic blood pressure in both Zucker fatty rats and spontaneously hypertensive rats, suggesting that these natural products are enhancing insulin sensitivity.
On the other hand, Sambaiah and Srinivasa (1991) reported that common spices -cumin, cinnamon, ginger, mustard and tamarind added to normal and hypercholesterolemia-inducing diet did not show any cholesterol lowering effect when added in the diet of the rat at about 5-fold the normal human intake.
Cinnamon has been investigated in human studies for its antidiabetic properties.
For instance Khan et al. (2003) demonstrated that intake of 1, 3, or 6 g of cinnamon per day significantly reduced serum glucose, triglyceride, LDL cholesterol and total cholesterol in people with type 2 diabetes suggesting that the inclusion of cinnamon in the diet of people with type 2 diabetes could reduce risk factors associated with diabetes and cardiovascular diseases.
Though the Mang et al. (2006) trial also observed a significant decrease in fasting glucose, the magnitude of the effect was far less dramatic; no significant change was observed in lipid profile markers or in HbA1c after cinnamon intake.Recently Wang et al. (2007) reported significant reductions in insulin resistance in women with polycystic ovary syndrome treated orally by cinnamon.
On the other hand, Vanschoonbeek et al. (2006) did not observe a significant change in blood sugar or lipid profile markers.Similar results were observed by Suppapitiporn et al. (2006).They demonstrated that cinnamon powder 1.5 g /d did not have any significant effect in reducing fasting plasma glucose, HbA1c and serum lipid profile in type 2 diabetic patients.
In the present study lipid profile parameters, calcium and albumin were unaffected by cinnamon intake by broiler chickens.
The discrepancy between our data and results of other animal experiments could be due to a number of factors, including differences in the effect of cinnamon between species, cinnamon concentration, cinnamon source (quality and chemical characterization), animal genetics or sex.
No adverse effect of cinnamon in doses used in animals was recorded.
This prelimitary study about effects of different doses of Cinnamomum zeylanicum on blood biochemistry showed that 38 d administration of cinnamon caused a significantly lower plasma glucose level by broiler chickens.
The presence of cinnamon in the diet decreased the levels of blood glucose and its effect on blood glucose tended to be dose-dependent.Cinnamon in the used doses had no adverse effect on the metabolism of chicks.