Investigation of the presence of norovirus (GI, GII) and hepatitis a virus with real-time RT-PCR test in milk cans of small family enterprises that selling raw milk

In this study, the presence of Norovirus (NoV) GI, NoV GII and Hepatitis A Virus (HAV) was investigated in milk cans where the milk of dairy cows aged 24 months and older were collected from small family enterprises selling raw milk in Burdur-Merkez. For this purpose, milk samples were collected in 2 sterile tubes of 15 ml and 50 ml from milk cans in 100 dairy farms. While the presence of NoV GI, NoVGII and HAV was investigated by Real-Time RT PCR in 15 ml milk samples taken in sterile tubes, somatic cell count (SCC) was performed in 50 ml sterile tubes. A questionnaire on milking and hygiene conditions was also carried out in the sampling establishments. As a result of the questionnaire study on milking and hygiene conditions in enterprises; Milking of animals is mostly done by family members and the mother, milking is commonly carried out by machine, the most common vector that may cause environmental contamination in the milking area and barns is pests, monthly cleaning of the milking area and barns is generally carried out, daily cleaning of the milking areas is also carried out, after use and daily cleaning (cold water and once through water) is carried out in milk cans, but weekly disinfection is carried out in milking machines and cans, It was determined that the use of soap and water and hand washing habits before and after milking were common in the enterprises, but the use of hand disinfectants was not common, the use of aprons at the entrance to the milking area and at the entrance to the barn was not widely applied, the use of jewellery by the employees during the milking process was common, the rate of receiving any training on raw milk hygiene by the employees was at a very low level, and the annual milk analyses of the enterprises were carried out once a year. In the Real-Time RT-PCR analysis performed to determine the presence of NoV and HAV in milk samples taken from 100 small family enterprises selling raw milk in Burdur-Centre; 16% NoV GI, 12% NoV GII, 8% HAV positivity was detected. In the results obtained as co-infection; 4% NoV GI + NoV GII and 8% NoV GI + NoV GII + HAV were determined. In this study, the presence of NoV GI, NoV GII and HAV was detected in the milk collected in small family enterprises selling raw milk. The mean SCC in the milk obtained in the study was determined as 339.020+249.230.9. In this study, the mean SCCs of NoV GI, NoV GII and HAV positive samples were statistically lower than the mean SCCs of negative samples (p<0,05). The mean SCC of NoV GI positive samples was 225.375+60.018,9 (p=0,005), the mean SCC of NoV GII positive samples was 251.166,7+42.994,9 (p=0,01) and the mean SCC of HAV positive samples was 248.750+49.969,1 (p=0,04). It was concluded that the presence of NoV GI, NoV GII and HAV in milk did not affect SCC and could not be used as an indicator of viral presence in milk.