MILK FAT FREE FATTY ACIDS IN DEPENDENCE ON HEALTH OF DAIRY COWS

E. Samková, M. Klimešová, L. Hasoňová, D. Falta, P. Roubal, O. Hanuš, I. Němečková, M. Šlachta

Abstract: Free fatty acids (FFAs) in fat are important indicator of raw milk quality. The aim was to analyse the relationships and quantify effects of dairy cow mastitis on FFAs. Individual milk samples (IMSs; n 307) came form Holstein and Czech Fleckvieh cows (67 : 33%). Sampling was from 10 to 270 days in milk for 1 year. Cows were fed in stables (n 5) by total mixed ration. Herd lactation milk yield varied from 7000 to 10 000 kg. Milking was performed twice a day using pipeline milking equipment and in milking parlours (20 : 80%). IMSs were classified into 3 groups according to somatic cell count (SCC): A ≤ 150, healthy; B from 800 to 1500, subclinical mastitis; C > 1500 103.ml–1, subclinical and clinical mastitis. Lactose (L) decreased with growing intensity of mammary gland secretion disorder from 4.90 ± 0.278 (A) to 4.49 ± 0.44% (C; P < 0.001). The values increased in the same direction: content of FFAs from 0.65 ± 0.209 to 1.44 ± 0.379 mmol.100g–1(P < 0.001); milk energy quotients fat/protein (F/P) from 0.88 ± 0.386 to 1.23 ± 0.335 (P < 0.001) and fat/lactose (F/L) from 0.63 ± 0.266 to 1.98 ± 0.309 (P < 0.001). The mastitis state (SCC) deteriorated milk quality by increase of FFAs, 0.703 (P < 0.001; by 121.5%) and reduced L, –0.522 (P < 0.001). 49.4% of FFA variability could be explained by SCC variations. Increased SCC by 1000 103.ml–1 increased FFAs by 0.433 mmol.100g–1. The L decrease due to worse mastitis state or cow energy malnutrition increased FFAs, –0.312 (P < 0.001). A risk increase of ketosis coefficients (F/P and F/L) deteriorated milk quality by increase of FFAs, 0.395 and 0.443 (P < 0.001) where 0.1 is equal to 0.05 and 0.067 mmol.100 g–1. Values of FFAs can serve to control the health of dairy cows and quality of IMSs in regular milk recording.

Keywords: ketosis quotient; lactose; mastitis; raw cow milk quality; somatic cell count

Date published: 2017-08-28