Scientific Report on the Welfare of Dairy Cows, the Occurrence of Subclinical Mastitis and the Number of Somatic Cells in Milk

Safety and quality of dairy cows milk as well as welfare of animals raised for milk production are of growing interest to the general and professional public (EFSA 2009, 2009a, 2012, 2012a, 2015). Taking into account such circumstances, Croatian Agency for Agriculture and Food conducted a study with the aim to determine the state of welfare of cows on farms in the Republic of Croatia, to determine the safety and quality of milk and their interrelationship. The method of the Italian National Reference Center for the Assessment of Welfare CReNBA was used to assess welfare (Bertocchi and Fusi, 2014). Six farms were selected for the study, on which samples for laboratory tests were taken from animals in the second and third lactation. Welfare on farms was assessed, milk was analyzed for chemical and microbiological indicators, the number of somatic cells in milk was determined by rapid tests and laboratory methods, and biochemical indicators in the blood of cows were determined. According to welfare assessments, two farms belong to the upper grade and the others to the middle. Taking into account that welfare assessment protocol is based on animal mesures, infrastructure and management, and taking into account that the number of somatic cells is only one of the welfare measures, no strong relationship was found between the overall welfare assessment and the number of somatic cells. Awareness of the importance of implementing welfare measures has been found to increase, while many indicators showing that modern knowledge on feeding, water and air quality in facilities, as well as animal treatment are implemented. Nevertheless, the need for increasing bedding per head was determined. It is evident that existing milk quality control, by measuring the number of somatic milk cells from four quarters together, can mask the true state of udder health; a high number of somatic cells in one quarter may be masked (reduced) by the total number of somatic cells (false negative result), and the disease will not be detected in time. Mastitis-causing microorganisms have been identified independently of the number of affected quarters, both in cases of clinical and subclinical mastitis. Distribution of the increased number of somatic cells by quarters (> 400,000), showed that 34% of cows had one quarter affected, 22% two quarters, 11% three quarters, and 5% of cows had inflammation in all four udder quarters . Existing rapid tests have been confirmed to be suitable for the detection of mastitis, and more sensitive tests should be developed in the detection of subclinical mastitis.