Indigenous goats play an important role in the semiarid region of Brazil as a biological resource with great genetic variability and historical value. They are raised in the traditional manner because they are rustic animals, commonly used for milk and meat production. Therefore, understanding their nutritional requirements is important for a successful nutrition system because animals fed properly will more efficiently convert the nutrients ingested in products. The objective of this study was to determine net energy (NE_g) and protein (NP_g) requirements for growth of 36 male Moxotó goat kids (15.69 ± 0.78 kg initial BW), grazing in the semiarid region of Brazil. Four kids were slaughtered at the beginning of the experiment (baseline group, 15.37 ± 0.30 kg BW) and the remainder (n = 32) were allocated randomly to one of the 4 levels of concentrate supplementation (treatments groups: 0, 0.5, 1.0 and 1.5% BW), with 8 kids per group. When the animals in the 1.5% BW treatment group reached 25 kg BW, the animals in the other treatment groups were also slaughtered. The individual whole empty body was weighed, ground, mixed and sampled for chemical analyses. We used the comparative slaughter method to assess body composition and calculate the nutritional requirements. Linear regressions were used to determine the relationship between the shrunk BW and the empty body weight (EBW). The allometric equations were calculated using the relationship between the amount of fat, energy and protein and the EBW. Body composition varied from 156.40 to 171.52 g of protein, from 65.20 to 138.44 g of fat and from 1.56 to 2.51 Mcal of energy per kg of EBW. The ratio of EBW/BW was 0.81. The NE_g requirements to gain ranged from 2.85 to 4.58 Mcal/kg EBW gain and NP_g to gain ranged from 181.36 to 198.78 g/kg EBW gain for the castrated indigenous goat kids weighing between 15 and 25 kg. This study has indicated that castrated Moxotó goat kids have different protein and energy requirements in relation to those values commonly recommended by feeding system for other breeds.