CORRELATIONS BETWEEN SOMATIC CELL COUNT AND MILK QUALITY IN TWO DAIRY FARMS FROM NORTH-WESTERN ROMANIA

Abstract

The objectives of this study were to achieve an epidemiological investigation on subclinical mastitis in dairy cows and to evaluate milk quality according to factors such as somatic cell number, protein, fat, dry matter, freezing point. The study was carried out during 2014 in two farms located in north-west of Romania. Detection of subclinical mastitis at farm A was carried out using MAST-O-TEST method and at farm B by KERBATEST method. In terms of temporal evolution, the highest incidence of subclinical mastitis was recorded in summer (farm A: 4.38%, 5.18%, 5.78% and farm B: 4.46%, 5.36%). Regarding subclinical mastitis incidence in relation to age of the animals, the highest values were observed in animals ranging from 4-6 years (62.75% - farm A and 60.00% - farm B). The epidemiological study conducted in relation to the stage of lactation showed that the highest rate was recorded in cows in the 4th lactation (47.55% - farm A and 48.57% - farm B). The overall analysis of the results relating to the anatomical positioning of the affected quarter revealed that the highest frequency was observed in the hindquarters (68.16% - farm A and 68.57% - farm B). A higher incidence of subclinical mastitis was observed during summer season and therefore biochemical analysis and determination of somatic cells number (SCC) were performed only during this period. For these determinations an automated system - CombiFoss was used. The control group (C) showed SCC values between 130 - 300 SCCx10-3 mL-1 while in mastitis group (M) the number of somatic cells was between 678 - 1,705 SCCx10-3 mL-1. The mean values for the other parameters were as follows: dry matter (C-10.18%, S-8.36%), protein (C-3.41%, S- 2.88%), fat (C-4.06%, S-3.28%), freezing point (C-0.529, S-0.609).