Evaluation Bactericidal Effect of Horse Milk against Brucella

Brucellosis is a highly infectious disease affecting both animals and humans. The current standard tools for the diagnosis of this bacterial infection are serological and microbiological. Brucellosis is zoonosis diseases that are caused by four species of Brucella, have a high morbidity that can cause a highly contagious disease in sheep, goats, cattle and one-humped camels. The bacterial strain were sequenced by PCR and was Brucella melitensis. The aim of this study was to evaluate the role of horse milk against Brucella melitensis. Horse milk was prepared from Tehran Jockey Club. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Brucella spp. were determined by broth macrodilution and agar well diffusion methods. Introduction Brucella is a facultative intracellular pathogen and one of the etiological agents of brucellosis which is a highly common bacterial zoonosis worldwide that can infect humans and animals and cause economic losses [1,2]. It is considered as an endemic disease in Mediterranean Middle East, Western Asia, Africa, and Latin America [3] Persian Gulf [1]. Although Iran have put into effect programs to control and eradicate brucellosis, the disease still occurs in the country [4,5]. Brucella species are often categorized according to the principal farm animal they infect [2. Infection with Brucella abortus cause several consequences in horses. The most common disease is supra spinouts bursitis (fistulous withers), which results from the apparent predilection of the organism for synovial structures [6]. This is marked by a painful swelling over the withers which may open and drain purulent material [7]. Supra atlantal bursitis (poll evil)may also be caused by B. abortus infection [1]. Moreover, B. abortus infection is an infrequent cause of abortion in mares and infertility in the stallion [8]. Great efforts were being made to eradicate B. melitensis all over the world [5]. After invasion of the lymphoid system, the bacteria are developed within mononuclear phagocytes, and the infected cells play a crucial role in the dissemination of the bacteria in specific locations of the body such as spleen, brain, heart, and bones. Brucella species virulence and chronic infections are thought to be due to their ability to escape killing mechanisms within macrophages, such as lysosomal enzymes and products of the oxidative burst. In spite of the improvements in food hygiene and food production techniques, food safety is an increasingly important public health issue. For this reason, to produce safe foods new methods are still needed, to possibly in combination with the existing methods, reduce or inhibit food borne pathogens. Because of increasing pressure from consumers and legal authorities, food industry has tended to reduce the use of chemical preservative since their products to either completely nil or to adopt more natural alternatives for the maintenance or extension of product shelf life. The aim of this study was to screen in vitro antibacterial activity of mare milk against B. melitensis isolates. Materials and Methods Mare Milk Collection Horse milk was prepared from Inqilab Jockey Club of Tehran, then was transferred to the laboratory. Bacterial Strain The B. melitensis strain used in this study was isolated from aborted sheep fetus with acute brucellosis. It was identified to the species level by conventional methods (the requirement for CO for growth, production of HS, urease production, sensitivity to fuchsine and thionine, and agglutination with specific antiserum). Extraction of DNA carried out and then IS711specific gene amplified by Polymerase Chain Reaction by IS711specific gene. A class ІІ biological safety cabinet was used. This strain was stored in skim milk at −70 °C and twice sub cultured before starting the study. Bacterial Culture For infection experiments, B.melitensis was grown for 48 h in 2YT (peptone; 16 g, sodium Chloride; 5 g, meat extract; 10 g, distilled water;1 liter, (Difco, BD, Spars, MD) with 5% sterile. Horse serum. Bacteria were suspended in a sterile phosphatebuffered saline (PBS). Abundance of B.melitensis in PBS was