Effects Of Melaleuca Alternifolia Oil On The Immune Function Of Broilers

With the rapid development of poultry breeding in C hina,the amount of types and use of antibiotics which are used in poultry breeding have increased.Long-term use of antibiotics can bring considerable economic benefits,along with the drug residues,the production of the drug-resistant bacteria,animal immune function decline and other hazards,even through the environment pollution or drug residues in livestock and poultry and its secondary product cause potential harm to human health.Many countries have begun to strictly regulate the use of antibiotics,looking for substitutes for antibiotics is becoming a hot area of research at home and abroad.Melaleuca alternifolia oil,called tea tree oil,is an essential oil with broad-spectrum anti-microbial properties.Many studies have shown that melaleuca alternifolia oil has anti-inflammatory effects and well regulating effects on inflammation,and it is a good natural immune enhancer.Interiorly melaleuca alternifolia oil has been widely used in medicine and health,household chemical,spices,food,pesticides and other industries,but the application in poultry industry is still less.This paper is to investigate melaleuca alternifolia oil on the immune function of broilers and its mechanism,which provides the theoretical basis for melaleuca alternifolia oil applying to the poultry breeding.This experiment divides into two parts : in vivo experiment and in vitro experiment.In vivo experiment,different concentration of melaleuca alternifolia oil product(0.6‰ and 1‰)were added in drinking water,blood samples were collected at the age of 14,28 and 42 to measure the content of globulin,IgG,IgA,IgM,IL-1,IL-2,IFN-? and IFN-? in serum.Intact thymus,spleen,bursa of fabricius were collected at the age of 45 to measure the index of immune organ and made into paraffin section,to observe the organization structure of the immune organs.The results show that melaleuca alternifolia oil can promote the secretion of chicks IgG,IFN-?,inhibit the secretion of IL-2,increase the thymus and bursa of fabricius cortex and medulla ratio,promote the proliferation of thymus cells and the maturity of lymphocytes.In vitro experiment is to study the effect of different concentration of melaleuca alternifolia oil on the chicken peripheral blood lymphocytes proliferation and its secretion of cytokines.Through cultivation of the chicken peripheral blood lymphocytes in vitro,the final concentration of 10?g/mL ConA and different final concentration of melaleuca alternifolia oil(0.00025%,0.0005%,0.001%,0.00125%,0.002%)were added to medium,and it was cultured for 24 hours,measuring the surviving number lymphocyte and the content of IL-2,IL-4,IL-6,IL-10 and IFN-? in the cell culture supernatant.The results show that the experimental concentrations of melaleuca alternifolia oil have no toxic effects to chicken lymphocytes and can promote the proliferation of lymphocytes.Melaleuca alternifolia oil can promote the secretion of IL-6 and IFN-?,inhibit the secretion of IL-10.It shows that melaleuca alternifolia oil can regulate immune activity through regulating lymphocyte secretion of cytokines.The research results show that melaleuca alternifolia oil can play a role in immune regulation by enhancing immune responses,promoting the immune organ cell differentiation and regulating lymphocyte secretion of cytokines,this study reveals the mechanism of melaleuca alternifolia oil on the immune function of broilers,to provide experimental data and theoretical basis for melaleuca alternifolia oil applying to poultry breeding.Research for the influence of melaleuca alternifolia oil on broiler immune organs organization structure is almost blank research field,this paper results also provide reference and theoretical basis for the research in future.