In the Netherlands it is general practice that dairy cows have a dry period of six to eight weeks. Research, however, shows that omission of the dry period avoids the negative energy balance after calving with its potential negative effects on metabolic disorders, infectious diseases, and fertility. On the downside, no dry period (NDP) causes a loss of milk production per cow compared with a conventional dry period (CDP). The objective of this research was to make an economic comparison between CDP with a sixty day dry period and NDP. Data on milk production per cow and on replacement rate, being the possible result of improved health, were taken from five farms involved in a research project on the effects of NDP, both from the year before and the year after switching from CDP to NDP. These data show that the replacement rate was on average 37% in the CDP situation while it was 24% in the NDP situation. Milk production was on average 13% lower in the NDP situation while fat and protein content of the milk were 0.21% and 0.42% points higher. A whole farm dairy linear programming model maximizing labor income (returns to family labor and management) was used to determine the technical and economic results for the situation with CDP and NDP. Results were calculated for three scenarios (one with milk quota and two without milk quota), representing differences in possibilities for increasing the farm size. Results show that under each scenario NDP is more profitable than CDP. The increase in labor income varies from 20% to 42%. This means that the negative effect of a lower milk production per cow is outweighed by the positive effect of a lower replacement rate and higher milk components. Sensitivity analysis shows that under a milk quota scenario NDP always results in a higher labor income than CDP irrespective of the change in replacement rate and milk production loss. Under the scenarios without milk quota a replacement rate of 34–35% or a milk production loss of 19–21% with NDP would result in a comparable labor income. The conclusion of this research is that NDP gives better economic results than CDP in a dairy quota situation for a broad range of replacement rate reduction and milk production reduction. In a situation without dairy quota, the replacement rate should be at least 3% points lower and milk production should be not more than 19% lower in the NDP situation to end up with better economic results.
- holstein herds
- short 35-d