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Diet selection by grazing animals is determined by genetic and environmental factors that interact and affect their efficacy for managing vegetation as targeted grazers and developing animals adapted to local grazing environments. The effect of rearing environments on the percentage of dietary juniper (Juniperus spp.) of goats, that for 15 years were divergently selected for high (J+) or low (J-) juniper consumption, was investigated using a factorial design 2 × 2 (rearing environment— selection line). Eighty pregnant does from both selection lines were grazed on either juniper-infested (JIR) or juniper-free (JFR) rangelands until their kids were weaned at about 75 days of age. Faecal samples were analysed with faecal near-infrared reflectance spectroscopy to determine the percent juniper in the diet. After weaning, kids from both rearing environments grazed JIR. The J+ does always consumed more (P < 0.001) juniper than J-does, demonstrating different maternal role models for kids reared in the JIR environment. The percentage of juniper in J-kid diets (7%) was the same regardless of the rearing environment. However, the rearing environment affected the percentage of juniper in the diet of J+ kids, resulting in a gene-environment interaction (P=0.022). The percentage of juniper in the diet of J+ kids reared in JFR (16%) and JIR (24%) were about two and three times higher than J-kids, respectively, indicating that genetics and the rearing environment contributed about equally to the increase in the percentage of juniper in the J+ kid diets. Regardless of the rearing environment, the J+ kids had a higher percentage of dietary juniper than J-kids (P<0.001). The ability to select animals with specific dietary preferences and proper rearing environments holds promise for targeted grazing strategies to restore degraded rangelands, with potential applications in conservation and ecosystem management.