Publications

Why dry or why not? – pros and cons of shortening or omitting the dry period for cow and calf health

Knegsel, A.T.M. van; Kemp, B.; Kok, A.

Summary

It is well known that shortening or omitting the dry period in dairy cows results in a more positive energy balance and improves metabolic status in early lactation, due to lower milk yields and sometimes also improved energy intake. Moreover, the improved energy balance due to shortening or omitting of the dry period is related with improved reproductive performance. Besides these benecial health effects, shortening or omitting of the dry period has potential detrimental consequences for animal health and performance. Shortening and omitting of the dry period results in a reduction in milk yield in the subsequent lactation. Furthermore, specically omitting of the dry period results in: (1) lower antibody levels both in colostrum and in plasma of calves during the early weeks of life; and (2) loss of opportunity to treat cows with an elevated somatic cell count with dry cow antibiotics during the prepartum period. Dry period length in relation to animal health, performance and management was the focus of 2 large research projects and several PhD theses at our group in the last decade. This contribution gives an overview of benets and drawbacks of shortening or omitting of the dry period for both cow and calf health and discusses how customising dry period management based on individual cow characteristics could make use of the benets and limit the drawbacks of shortening or omitting of the dry period. Specic cow characteristics like somatic cell count, milk yield level, parity and disease history were input variables for a decision support model to optimize dry cow management (dry period length and use of dry cow antibiotics) at cow level. Customising dry period management using this decision support model resulted in a reduction in milk yield losses at herd level, compared with shortening or omitting of the dry period for all cows. Furthermore, customising dry period management resulted in a reduction in use of dry cow antibiotics, did not affect udder health, but tended to reduce the incidence of other diseases in the peripartum period.