عنوان مقاله [English]
Introduction:Under current husbandry conditions, veal calves are often affected by different disease. Various factors could cause these disease in calves. After birth, calves are separated from their mothers, preventing the calf from picking up the protective gut flora from its mother. Furthermore, at a very young age, the animals are faced with major stress events like transportation, marketing, dietary changes and exposure to a variety of infectious agents. Consequently, animals consume less milk, are predisposed to loss of barrier function of the gut and may suffer from impaired immune function. Moreover, the protective potential of the microbial gut flora tends to decrease For example, during stress events, the trend is for the productive lactobacilli to decrease and for coliforms to increase. To prevent the opportunistic pathogenic flora from flourishing, current practice is to treat calves with antibiotics during the first 5-10 days after arrival (Soltan. 2009). However, the antibiotics diminish not only the activity of pathogenic flora, but also that of the
productive flora. A ban on antibiotics as feed additives in animal nutrition is realized since 1986 in Sweden and 1999 in Switzerland. With the restricted use or ban of dietary antimicrobial agents, we must explore new ways to improve and protect the health status of farm animals, to guarantee animal performance and to increase nutrient availability. Accordingly, there is greater interest in using plants and plant extracts as alternatives to feed antibiotics. Beneficial effects of
essential oils on farm animals may arise from activation of feed intake and secretion of digestive secretions, immune stimulation, anti-bacterial, coccidiostatic, antiviral and antioxidant properties (Wenk. 2003). Echinacea purpurea is one of the most important medical herbs. It is widely used around the world to treat common cold and other infectious disorders with the claim to have paramunity-inducing and non-specific immune responses stimulating effects (Böhmer et al. 2009). Echinacea increased phagocytic activity of alveolar macrophage and resulted an enhanced release of cytokines (such as TNF-α and IFN-γ) in rat’s spleen macrophage (Goel et al. 2002). Considering the beneficial effects of Echinacea purpurea in traditional medicine as well as its regulating effect on the immune system, it seems that the use of Echinacea purpurea as a food additive can have beneficial effects on the immunity and performance of dairy calves.
Material and methods: This experiment was carried out on Astan Quds Razavi farm. Twenty-four one day old Holstein female calves were divided into four treatments with eight replicates. The experiment was conducted as a completely design. Levels of 0, 350, 700 and 1050 mg/day/per calf Echinacea purprea extract were added to treatments 1 to 4 respectively. The Echinacea purpurea extract was purchased from the Zardband pharmaceuticals Company. The extract was added to milk in per weaning period and to drinking water in post weaning period. Calves were kept in separate pen until the end of the experiment. Animals had ad libitum access to water and dietary. Daily feed intake and monthly body weight measured and blood samples were taken monthly.
Results and discussion: The results showed that the effect of experimental treatments on body weight gain was not significant in per weaning, post weaning period and whole experiment. Similarly, other previous researchers (Hermann et al. 2003, Maass et al., 2005) did not find positive effect of Echinacea purpurea on pigs performance also in another study that was carried out on broilers and layers indicated that different levels of Echinacea did not have any effect on body weight (Roth-Maier et al., 2005).The results indicated that feed intake was not affected by treatments during per weaning, post weaning and whole period. The findings of some previous studies indicated that use of Echinacea purpurea as feed additive did not effect on feed intake of pigs ((Hermann et al., 2003; Maass et al. 2005). Differences in blood metabolites concentration were not significant between treatments. Agreed with our results Hadhoud (2014) reported that supplemented goat’s diets with Echinacea purpurea at level of 4 or 8 g/ kg DM, had no effect on blood serum albumin, globulin, urea, glucose, ALT, AST, cholesterol and triglycerides concentrations although it significantly increase blood serum total protein of the treated goats. Interleukin 10 concentration was significantly higher in treatment 4 compared to control treatment (p<0.05). In a study showed that N alkamides isolated from Echinacea induce activity on cannabinoid receptor type-2 (CB2) and ultimately lead to immunomodulatory effects along with the superstimulation of interleukin 10 (IL 10) in vitro (Chicca et al. 2009). Immunoglobulin G concentration was significantly higher in treatment4 than control treatment (p<0.05). In a study the rats were injected intraperitoneally with KLH (Calbiochem, San Diego,CA) antigen, 10 µg/kg, on Day 0 then were treated with 3.3 g commercially available E. angustifolia root extract per 1 liter of drinking water, they showed a significant augmentation of their primary and secondary IgG response to the antigen(Rehman et al., 1999). Concentration of tumor necrosis factor alpha affected treatments and was significantly higher in 4 treatment compared 1 treatment (p<0.05). Similarly our results in a study showed a trend of increase in TNF-α and nitric oxide release by the alveolar macrophages following an in vitro stimulation with Lipopolysaccharides of Echinacea was also evident. An enhanced release of cytokines (such as TNF-α and IFN-γ) in response to Echinacea components, was also apparent in rat’s spleen macrophage (Goel et al. 2002).
Conclusion: our results showed Echinacea purpurea had no effect on performance, feed intake and blood metabolites but significantly improved immune system parameters as we expected.