The possible effect of protein-enriched Opuntia cladode supplementation during the pre- and post-partum stages (−25 days to +15 days; day 0 = kidding) upon dam–kid metabolic status, colostrum-milk quality, and some behavioral kid-to-dam interaction in goats managed under rangeland extensive conditions was evaluated. Multiparous crossbred goats (n = 30), homogeneous regarding live weight (LW; 55.9 ± 1.03 kg) and body condition score (BCS; 2.5 ± 0.2 units), were randomly assigned to (1) protein-enriched Opuntia (PEO; n = 10; 29.8% crude protein (CP), 2.2 Mcal ME kg−1), (2) non-enriched Opuntia (NEO; n = 10; 6.4% CP, 2.1 Mcal ME kg−1), and (3) control (CON; n = 10, non-supplemented). The PEO and NEO goats were individually supplemented with Opuntia cladodes (250 g day−1; 09:00–10:00 a.m.; 25 days pre- and 15 days post-partum); then, all groups grazed in a marginal rangeland (10:00 a.m. to 06:00 p.m.). LW, BCS, and blood samples to quantify serum glucose (GLU) levels were collected weekly from day −25 up to day +15 in both dams (pre- and post-partum) and kids (post-partum). At 4 h and 8 h post-partum, kid-to-dam behavioral tests were performed; approaches (APRO, units), animal-to-animal contact (ACONT, s), latency-to-contact (LCONT, s), and high (HPB) and low (LPB) bleats were registered. The response variables LW (58.2 ± 3.5 kg), GLU from does (66.4 ± 3.3 mg/dL), colostrum fat (12.3 ± 1.15%), non-fatty solids (20.9 ± 2.1%), density (64.4 ± 7.0%), and protein (8.1 ± 0.8%), as well as milk density (31.2 ± 1.7%) and protein (3.9 ± 0.3%), favored the PEO group. Moreover, the dam-to-kid 4 h LPB (34.5 ± 4.6 frequency), as well as kid-to-dam 8 h LCONT-own (100 ± 35.5 s) and LPB (25.2 ± 6.9 frequency) also favored the PEO group. To conclude, peripartum supplementation with protein-enriched Opuntia cladodes emerged as a key alternative to enhance the dam–kid metabolic status, to improve colostrum quality and some milk components (density and protein), as well as to expand the kid-to-dam bond in goat production systems under marginal extensive conditions.