Leitner, G., Emritius Senior Scientist, National Mastitis Reference Center, Kimron Veterinary Institute, Ministry of Agriculture and Rural Development, P.O. Box 6, Bet Dagan, 50250, Israel; Rovai, M., Assistant Professor / Extension Dairy Specialist, Dairy and Food Science Department, Alfred Dairy Science Hall, 113N South Dakota State University, Box 2104, Brookings, SD  57007, United States;

The effects of subclinical intramammary infection (SCIMI) in sheep are ignored in most cases by both the farmers and the industry. Due to the high prevalence of coagulase negative staphylococci (CNS) and the lack of feasibility to treat the infection during lactation, prominent actions must concentrate on its prevention. On the sheep level, SCIMI caused by CNS clearly reduces milk yield and changes milk composition that directly influence the product's properties. High proportion of milk from infected glands in the milk tank is associated with higher losses of fat and protein in the whey during the coagulation process. Moreover, extended storage of milk, irrespective of its initial quality, deteriorates its final quality for cheese making and extended storage of low-quality milk before processing, further increases this deterioration. Studies related to the quality of cheese and yogurt indicated that milk composition has been changed owing to the presence of different bacteria. The review aims to draw attention to the effects of SCIMI in sheep caused by CNS on milk production losses along with changes in its composition that influences milk coagulation properties and chasse yield. © 2019