We investigated whether different rearing conditions affected the physical development, ease of integration into the dairy herd and performance of primiparous dairy cows and the results are reported in this Research Communication. The three rearing conditions investigated were whole-day cow-calf contact for 9 weeks (WDC), half-day contact for nine weeks (HDC) and no mother-contact (NC) with nipple-bucket-feeding (max. 2 × 3 l/d) and group-housing from the 8th day onward. After permanent separation from the dams (WDC and HDC), all calves had been nipple-bucket-fed and gradually weaned from week 10 to 13 of life and kept together as calves and heifers. Measures of physical development were trunk girth, height at withers and body weight. Lying behavior during the first 48 h after introduction to the dairy herd after first calving was used as an indicator of ease of integration. Performance measures were age at calving, lactation duration, milk yield and culling rates during the first lactation. No differences between WDC and HDC could be detected. Moreover, no treatment-effects on physical development or performance could be found. All treatments showed reduced lying for the first 24 h after introduction to the dairy herd. Afterward NC-heifers lay less than WDC, with HDC-heifers ranging in between. We conclude that under the conditions investigated higher weights two weeks after weaning in WDC- and HDC-calves did not carry through to the first lactation and did not lead to earlier maturity and higher performance, but that integration into the herd may be alleviated when calves have early experience of the herd and associated conditions.

Interest in dairy calf rearing systems with cow-calf contact during the milk feeding period is increasing among farmers, advisors and researchers, but socio-economic consequences have only scarcely been investigated yet. In this research reflection we develop a suggestion for a socio-economic methodical framework that is suitable for the wide variation of cow calf rearing systems, farm, market and societal conditions. Based on a literature based, system-theoretical structuring of involved elements, and on full cost accounting in an exemplary case study concerning two model farms, we itemize monetary factors, and additionally important non-monetary factors, that should be included in a socio-economic evaluation. This process also revealed further research needs. We propose as a next research step to gather a greater number of real farm data including different rearing systems and to perform individual full cost accountings, in order to identify input and output patterns on this basis. This might not only help to provide a robust basis for economic decision making, but also help to fill research gaps concerning long-term effects of calf rearing with cow contact. In addition, ways should be explored on how to take non-monetary effects into account.

Due to increasing public concern regarding separation of the dairy cow and calf within the first days after birth, alternative systems, where cows and calves stay in contact for an extended period, are receiving increasing interest from a broad array of researchers and other stakeholders. With more research in the area, there is a risk of inconsistencies emerging in the use of terminology. To create a better consensus in further discussions, the aim of this Research Reflection is to provide definitions and propose a common terminology for cow-calf contact in dairy production. We also suggest definitions for various systems allowing cow-calf contact and describe the distinct phases of cow-calf contact systems.