Understanding the reproductive performance of a dairy cattle herd by using both analytical and systemic approaches: a case study based on a system experiment

Abstract

Reproductive performance has recently been a growing concern in cattle dairy systems, but few research methodologies are available to address it as a complex problem in a livestock farming system. The aim of this paper is to propose a methodology that combines both systemic and analytical approaches in order to better understand and improve reproductive performance in a cattle dairy system. The first phase of our methodology consists in a systemic approach to build the terms of the problem. It results in formalising a set of potential risk factors relevant for the particular system under consideration. The second phase is based on an analytical approach that involves both analysing the shapes of the individual lactation curves and carrying out logistic regression procedures to study the links between reproductive performance and the previously identified potential risk factors. It makes it possible to formulate hypotheses about the biotechnical phenomena underpinning reproductive performance. The last phase is another systemic approach that aims at suggesting new practices to improve the situation. It pays particular attention to the consistency of those suggestions with the farmer's general objectives. This methodology was applied to a French system experiment based on an organic low-input grazing system. It finally suggested to slightly modify the dates of the breeding period so as to improve reproductive performance. The formulated hypotheses leading to this suggestion involved both the breed (Holstein or Montbé liarde cows), the parity, the year and the calving date with regard to the turnout date as the identified risk factors of impaired performance. Possible use of such a methodology in any commercial farm encountering a biotechnical problem is discussed.

Strategies for time of culling in control of paratuberculosis in dairy herds

“…Poor reproduction in a herd can be due to both low conception rate and low heat detection rate, and the reasons can be a mixture of health problems, nutrition, high milk yield, and management routines (Dobson et al, 2008;König et al, 2008;Gouttenoire et al, 2010;). We focused on the heat detection rate, which is influenced primarily by the methods and strategies used for heat detection (Firk et al, 2002).…”

Modelling within the livestock farming systems research field: from cows to birds and farmers

“…Other modelling papers dealing with the environment at system level are, for example, Vayssiè res et al Cows are the main target in the second paper (Gouttenoire et al, 2010) that deals with a non-systemic issue (reproductive performances of dairy cows), but with the necessity to choose a systemic approach to asses and solve it. More precisely, the authors propose to combine both analytical and systemic approaches arguing with the complementarity of physiological knowledge on animals and management strategies of the decision-maker (the stockbreeder).…”