Table 2.

Milk production during the first 30 d in milk in ¾ Holstein × ¼ Gir dairy cows classified with subclinical hypocalcemia (SCH; n = 11) or normocalcemia (NORM; n = 21)^a,b,c

Item	SCH	CON	SEM	P-value
Milk production
Milk yield, kg/d	24.3	23.9	1.2	0.81
Fat-corrected milk, kg/d	27.7	28.8	1.5	0.60
12% total solids-corrected milk, kg/d	26.9	27.5	1.4	0.78
Energy-corrected milk, kg/d	27.9	29.0	1.5	0.62
Milk composition
Fat, %	4.34	4.81	0.20	0.09
Protein, %	3.31	3.45	0.05	0.10
Lactose, %	4.45	4.55	0.04	0.06
Total solids, %	13.23	13.84	0.21	0.05
Somatic cell count, cells/μL	398	198	74	0.05

^aResults are reported as least square means covariately adjusted to previous 305-d mature-equivalent milk yield from each cow, and separated using least square differences.

^bBlood samples were collected twice daily during the initial 5 DIM. Cows were classified as SCH when mean total serum Ca was ≤2.125 mmol/L and as NORM when >2.125 mmol/L.

^cFat corrected, energy corrected, and total solids corrected were calculated based on daily milk yield and concentrations of fat, protein, and total solids of the concurrent week (NRC, 2001).