The effect of year, month, region, and herd size on bulk tank somatic cell and standard plate count, and the determination of optimum herd size in the intensive Holstein Friesian dairy farms in the Turkish Republic of Cyprus

The objective of this study was to determine the effects of mount, year, region, and herd size on the bulk tank somatic cell count (SCC) and standard plate count (SPC) and total milk production of Holstein Friesian cows and to decide for optimum herd size in Northern Cyprus. The total number of cattle was 64,450 heads and the number of enterprises was 168 in 2016. The milk samples were collected once or twice a month from each herd. SCC and SPC were determined with the Fluoro-opto-electronic counter method. Herd sizes were described from small to extra-large enterprises for Northern Cyprus conditions and six groups were created. The least squares means were compared among the herd size, region, month, and year for the data set. From 2012 to 2016, there was a significant amount (39.49%) of increase in milk production. While the total share of the enterprises which sold chilled milk was 22.36-28.82% in 2012-2016, the chilled milk production corresponded to 71.7-79% of all the dairy market. Bulk tank SCC numbers were found to be significantly higher in herds smaller than 40 and larger than 200 heads (P < 0.05). In the medium-sized enterprises (40-150 heads, Groups 2, 3, and 4), the number of bulk tank SCC was below the threshold level (400,000 cells/mL). The number of bulk tank SPC was found to be significantly higher in flocks with <40 heads and 150-199 heads (P < 0.05). Months had a significant fixed effect on the amount of bulk tank SCC (P < 0.01) and the highest and the lowest SCC amount was found in August, September, and December, respectively. However, the effect on the SPC was found insignificant. The average SCC continued to decrease every year (2012-2016). The SCC values for 2016 were found to be statistically more significant than all the other years. The SPC values displayed a scattered pattern over the years. The weakest regions were the Gecitkale and Guzelyurt regions.