This is evidenced at the ligand level for Gh and Sl and at the receptor level for the ghr-i and ghr-ii genes, which are differentially regulated in liver and skeletal muscle, helping to distinguish stressful and growth disturbances due to overwintering or malnutrition as a result of changes in feed intake, protein and lipid feedstuffs or any other specific nutrient. This evidence concerns the gene GH1 and malnutrition.