Variation in Herd Financial and Production Variables over time

Financial and DHI records from 1978 to 1981 from 126 dairy herds in Virginia and North Carolina were used to determine relationships among production and financial variables within herd over time. Herds averaged 6779 kg milk per cow and $369 net cash income per cow for 103 cows. Expenses were 82% of receipts. Herd effects accounted for more than 40% of the variation in both financial and production variables. Year effects were less than 10% for financial variables except total receipts and expenses and were negligible for most DHI variables. Correlations among financial and DHI variables were largest between herds and smaller within herd and year. A time series, cross-sectional analysis regressed net cash income and different types of expenses on DHIA variables within herd and year. Net cash income per additional kilogram of milk was $.22 at 5000 kg/cow per yr, decreasing to 0 at 8162 kg. Net cash income per cow decreased $7.70 per .1 added services per conception and $3.20 per 1% increase in culling due to changes in expenses. Crop hectares per cow and cows per man influenced receipts and expenses equally. Hired labor and cash interest per cow increased as milk yield exceeded 6000 kg per cow. Holding heifers open an additional month also increased interest by $4.80 per cow. Differences in relationships among and within herds indicate difficulty in attaining herd improvement demonstrated by financial and production averages for single years.