THE design and formulation of milking machine inflations can be directly related to mastitis levels for dairy animals. The design of liners (inflation) has been one of the reasons for high mastitis rates. The inner layer of an inflation can damage teat tissue, especially near the area of the teat orifice. This physical damage can break down natural barriers against bacterial invasion of the udder. Mastitis-causing bacteria can also enter the udder if the milking machine causes pressure differentials to occur across the teat orifice. Recommendations are made by which air reserve requirements may be minimized, which in turn will decrease the pressure differentials in the milking system with subsequent reduction in energy consumption by the unit. After minimal use, the pores and cracks on the inner surface of most rubber inflations are conducive to harboring bacteria even after machine clean-up. Silicone rubber inflations designed and tested by the authors do not become porous with use. Most inflations on the market have to be discarded after 800 to 1200 cow milkings. Silicone rubber inflations are non-porous and functional after 10,000 cow milkings.