Učinak broja somatskih stanica na prinos i sastav mlijeka u krava holštajnske pasmine

This study was conducted to assess the impact of somatic cell count (SCC) on the test day milk yield (TDMY) and milk composition parameters (fat, solids-not-fat, protein and lactose) of Holstein cows raised in the Kırşehir province of Turkey. A total of 1194 raw milk samples were collected from 195 Holstein cows at different stages of lactation (from 1 to 7), parities (from 1 to 3) and calving seasons (autumn, winter, spring and summer). Also, TDMY and milk composition traits were tested by SCC in four groups (500×103 cells/mL). For statistical evaluation, SCC data were converted to log10 base. The overall means of log10SCC, TDMY, fat, solids-not-fat (SNF), protein and lactose were determined as 4.95 ± 0.016, 33.36 ± 0.232 kg/day, 3.39 ± 0.021%, 9.04 ± 0.013%, 3.32 ± 0.005% and 4.92 ± 0.007%, respectively. Log10SCC, TDMY, fat, SNF, protein and lactose were significantly affected by the stage of lactation, parity and calving seasons (P201×103 cells/mL) had a lower TDMY than milk with lower SCC (500×103 cells/mL. It was concluded that SCC in milk should not exceed 500×103 cells/mL for Holstein cows, suggesting that monthly control of SCC may be effective for improving milk production and milk quality in Holstein cows.Ovim se istraživanjem želio ustanoviti utjecaj broja somatskih stanica (SCC) na dnevni prinos mlijeka (TDMY) i sastav mlijeka (masnoća, suha tvar, bjelančevine i laktoza) krava holštajnske pasmine u Kirşehiru u Turskoj. Ukupno 1194 uzoraka sirova mlijeka prikupljeno je od 195 krava holštajnske pasmine u različitim fazama laktacije (od 1 do 7), pariteta (od 1 do 3) i različitim razdobljima teljenja (jesen, zima, proljeće i ljeto). Također, ispitivan je broj somatskih stanica s obzirom na dnevni prinos i sastav mlijeka u četiri skupine (500×103 stanica po mililitru). Za statističku obradu podaci o broju stanica prikazani su u bazi 10 logaritma (log10). Ukupna srednja vrijednost log10 za SSC iznosila je 4.95 ± 0.016, za TDMY 33.36 ± 0.232 kg/day, za masnoću 3.39 ± 0.021 %, za suhu tvar 9.04 ± 0.013 %, za bjelančevine 3.32 ± 0.005 % i za laktozu 4.92 ± 0.007 %. Na ukupnu srednju vrijednost log10SCC, dnevnog prinosa, masnoće, suhe tvari, bjelančevina i laktoze statistički znakovito (P201×103 stanica po mililitru) imale su manji dnevni prinos mlijeka nego one s manjim brojem somatskih stanica (