EDTA-Tris: EDTA damage cell surfaces of bacteria and tris increases the bacterial permeability to the extra cellular solutes. Dose: 3.5mM EDTA + 0.5 mM Tris + 20 ml PBS, daily for 3 days, I/U ly. Lysozyme: It is an enzyme found in body fluids (milk, saliva, tears etc.) having bactericidal effect. It causes hydrolyses of the glycoside bond of peptidoglycan especially of gram positive bacterial cell wall. Dose: 2 mg + 20 ml PBS daily for 3 days, I/U ly. IMMUNOMODULATORS: Immunomodulators acts either by antibody production or by cell mediated immunity. Characteristics of Immunomodulators: Stimulates both specific and paraspecific immune responsiveness Non-toxic even at higher dose rate Short withdrawal period Low tissue residue Compatible with other drugs Not be an antigenic Defined biologic activity No side effect a. E. coli Lipopolysacharides (LPS) LPS is an endotoxin obtained from the cell wall of gram negative bacteria. Intrauterine infusion causes increase influx of polymorphonuclear leucocytes (PMNLs) into the uterus by chemotaxis. Also activates macrophages and monocytes. This activation produces Tumor Necrosis Factor (TNF) which synthesis Interleukin (IL)- 1, 6 and 8. Also influx of immunoglobulin (Ig) that helps in phagocytiosis and destruction of bacteria. Dose: 100 µg LPS + 30 ml PBS, I/U (only once) b. Oyster glycogen (OG) Oyster glycogen increases non-specific uterine defense due to marked increase leucocytosis by chemotaxis. Dose: 500 mg OG + 30 ml PBS, I/U (only once) c. Autologus plasma/serum Intrauterine infusion of autologus plasma or serum increases opsonizing ability of PMNLs. Opsonizing capacity increases complement, antibodies and opsonins. It is better to use in field condition due to readily available and cost effective. Dose: 20 – 30 ml Autologus plasma/serum, I/U (only once) d. Levamisole It is a non-specific immunomodulator commonly used as antiparasitic. It stimulates cell mediated immune response by potentiating the rate of T- lymphocyte differentiation. Dose: 2.5 mg/kg bwt on day 0, 2, 6, 10, 14, and 18 of estrus cycle, S/C ly. e. Leukoterine –B4 It is a potent chemo-attractant and stimulates migration of PMNLs into the uterine lumen. Dose: 30 nMol/L, I/U ly.