The objective of this study was to compare the reproductive parameters of N'Dalores and N'Dama in order to measure the degree of blood supply from the N'Dalore breed to the N'Dama animals reared at the Kila ranch. 18 male and 32 female N'Dalores and 16 male and 28 female N'Dama were monitored from puberty to breeding. The data collected was analysed and processed using R software version 2. The comparison of the modalities of the variables studied by analysis of variance and the test of comparison of means were done by the Tukey test. The N'Dalores males reached puberty at the age of 542.13±3.2 days with a weight of 238.42±0.8 kg, while the N'Dama males reached puberty at 458.3±2.6 days with a weight of 168.7±8.2 kg. The scrotal circumference of the N'Dalores at puberty reached 25.6±9.3cm, the correlation between scrotal circumference and weight was positive (r= 0.64±2.5). In the N'Dama, the scrotal circumference reached 22.5 ± 1.5 cm, the correlation between scrotal circumference and weight was positive (r=0.48±0.6). The age at first calving was 1407.08 ±51.43 days with a weight of 349.37±9.28 kg. The calving-to-calving interval was 537.32±6.52 days. The calving to fertility interval is 255.78±7.84 days, the fertilizing power is 0.71±5.17. The N'Dama females reached puberty at 472.47±1.41 days with a weight of 171.7±10 kg and calved at 1062±1.6 days with a weight of 217.6±4kg, while the calving-to-calving interval was 492.7±1.7 days and the fertilizing service interval was 172.2±0.4 days with a fertilizing capacity of 0.64±0.10. This study shows that Nelore blood supply improves the reproductive performance of N'Dama.
