Analysis of the diversity of breeding female productive trajectories : interest for modelling the functioning of suckling herds

Abstract

In suckling herds, farmers’ production projects lead to highly variable animal productivity and productiontemporal pattern. The objective of this paper was toanalyse the advantage of the notion of breeding femaleproductive trajectory to model herd functioning basedon six case studies. In the first part, six managementsrelated to breeding and replacement practices are presentedin relation to different production projects. Inthe second part, the analysis of management indicatesthat it is aimed at either decreasing or increasingwithin herd diversity of female productive trajectories.In the third part, consequences for modelling herdfunctioning are reviewed. Models of herd functioningshould take into account farmers’ decision as well asfemale biological behaviour. To simulate herd performances,it is therefore necessary to represent thegroups of females with the same productive behaviourand the switch of females between these groups too.The productive trajectory is both an indicator of therule for culling and an indicator of performance. Theinteraction between the farmer’s decisions and femalebiology means taking into account managementdelayed effects on the sustainability of breeding femalestock.