Risk status of semi-arid Zimbabwean indigenous cattle populations under conservation programs

Abstract

Indigenous cattle breeds play a crucial role in most agricultural systems, providing sustainable livelihoods, cultural value, and genetic diversity, well-suited to semi-arid environments. The study aimed to assess the population structure and risk status of three indigenous beef cattle breeds, Tuli, Mashona, and Nkone, focusing on effective population size (Ne), number of females (L), and additional risk factors. Pedigree records for 37,081 Tuli, 12,935 Mashona, and 9,489 Nkone cattle were analyzed using the online POPREP software. Pedigree completeness over six generations varied, with the lowest completeness observed in the Nkone (23.2%), and the highest in the Mashona (25.9%). Average generation intervals ranged between 6.4 and 11.0 years, with inbreeding rates per generation of 0.26% for Mashona, 0.32% for Tuli, and 0.18% for Nkone. Effective population sizes were estimated at 266 for Tuli, 182 for Mashona, and 135 for Nkone, classifying Mashona and Nkone populations as endangered and in need of conservation, while Tuli requires ongoing monitoring. Additional risk factors, including geographic concentration and cultural value, further confirm the endangered status of these breeds. These findings highlight the critical need to strengthen conservation efforts to preserve the genetic diversity of Zimbabwe’s indigenous cattle populations.