Subclinical mastitis in machine milked dairy farms in Punjab: prevalence, distribution of bacteria and current antibiogram

Materials and Methods Mastitis is the inflammation of mammary gland; it is a complex disease which continues to have a major economic impact on the dairy industry throughout the world [1, 2]. The losses due to mastitis in USAalone are 1.7 billion dollars [3] while in India the losses are estimated to be about Rs. 7,165 crores [4]. The term mastitis comprises two relatively independent health problems: clinical and subclinical mastitis [5]. Subclinical mastitis is bereft of any obvious manifestation of inflammation and is characterized by having no visible signs either in the udder or in the milk, but the milk production decreases and there is change in milk composition [6]. Subclinical mastitis is 3–40 times more common than clinical mastitis and causes the greatest overall losses in most dairy herds [2]. Mastitis is produced by interplay of the variety of pathogenic agents and bacteria are one of the major etiological agents of the mastitis. The infectious causes of mastitis are vast and at least, 137 infectious causes of bovine mastitis are known to date and in large animals the commonest pathogens are , , other spp. and Coliforms [7]. Mastitis is considered as one of the major cause of antibiotic use in dairy animals, conventional antibiotic treatment is fast losing relevance due to development of resistance to the antibiotics among the mastitis pathogens, cost consideration and undesirable residues in milk [8]. Identification of mastitis causing pathogen and the results of antibiotic resistance pattern of the isolated bacteria are important prerequisites for implementation of effective control of mastitis. Therefore the present study was conducted to see the prevalence, distribution and sensitivity pattern of bacteria in machine milked dairy farms.