Abstract :
There are numerous recent studies highlighting sustainability problems for the development of ruminant production systems (RPS)
while facing increasing human food necessities and global climate change. Despite the complexity of the context, in our view the
main objectives of the ruminants’ physiologist should be convergent for both industrialized (IC) and developing countries (DC) in
a common and global strategy of advancing knowledge. In DC, this means improving the efficiency of RPS, taking into account the
unique possibility of using rangelands. For IC settings, RPS should be revisited in terms of autonomy and environment- friendly
feeding and managing practices. Assuming that competition for feed/food use is still a crucial criterion, future ruminant feeding
systems (FeSyst) should preferably focus on lignocellulosic sources. According to biome distributions, and the recent increases in
volumes of crop residues and their by-products, the annually renewed volumes of these biomasses are considerable. Therefore,
we need to redesign our strategies for their efficient utilization at the local level. For this purpose, digestion processes and rumen
functioning need to be better understood. The renewed vision of ruminal digestion through the reduction of greenhouse gas
emissions is also a key aspect as it is an environmental demand that cannot be ignored. With regard to other ruminants’
physiological functions, accumulated knowledge could be mobilized into an integrative approach that puts forward the adaptive
capacities of animals to face variability in quantity and quality of supplied feeds. Basically, the reduction of inputs that were
traditionally used to ensure FeSyst will need more flexible animals. In that sense, the concepts of homeostasis and teleophorhesis
need to be updated and adapted to domestic species and breeds that were until now largely excluded from the dominant
productive systems. In conclusion, a more holistic approach of research targets is required in which physiological functions and
farmers’ practices must converge and respond to each particular situation in an integral, dynamic and flexible conceptual
perspective. From a scientific point of view, both for ICs and DCs, a broader range of experimental scenarios should be explored
in order to arrive at innovative practices and solutions that respect environmental, ethical and economical issues. The clear
challenge is to in evaluate the sustainability of RPSs. This includes, in our opinion, a strong interaction with other dis
Keywords :
feeding , adaptive capacity , environment , Ruminant , Sustainability
