The study is to determine a baseline data on the correlation of the white blood cells (WBC), red blood cells (RBC) and serum calcium (Ca) levels to milk yield of sixteen (16) heads of Holstein Friesian X Sahiwal lactating cows over a period of time.

The study was conducted by collecting blood samples twice with thirty (30) days interval. The first blood collection was carried out last February 22, 2019, followed by the second blood collection on March 23, 2019. The blood samples obtained after each blood collection were immediately analyzed in the laboratory to acquire the needed data such as RBC, WBC and serum Ca level. In addition, the thirty (30) days milk record of the sixteen (16) cows between the first blood collection and second blood collection was also acquired.

The result of the blood collected was correlated with the 30-day milk yield using simple correlation. The result showed that there was an inverse correlation of the WBC to that of the milk yield. The serum calcium showed a positive correlation to that of the milk yield. The RBC showed no correlation to that of the milk yield.

Thesis (Doctor of Veterinary Medicine)

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