Genetic Improvement of Bunaji Cattle for Milk Production Using Genomic Selection: An Original Breeding Programme Design and Validation Study for North West Nigeria

This dissertation develops and empirically validates an original genomic selection breeding programme for improving milk production in Bunaji (White Fulani) cattle in North West Nigeria, addressing the critical gap in the absence of a genomic reference population and validated selection index for this numerically dominant Nigerian breed. The Bunaji is the most important beef and dual-purpose cattle breed in Nigeria's North West zone, and improving its milk production potential through evidence-based genomic breeding represents the most achievable pathway to increased dairy output in the region without compromising breed adaptation. The dissertation employs a four-phase design: phenotypic characterisation of milk production traits in 800 Bunaji cows from 80 farms across Kano, Katsina, Sokoto, and Kebbi States; construction of a Bunaji genomic reference population using the BovineHD BeadChip SNP array on 600 genotyped animals with complete phenotypic records; genomic estimated breeding value (GEBV) calculation using genomic best linear unbiased prediction (GBLUP) and random regression models for lactation curve traits; and evaluation of alternative genomic selection index designs for the smallholder production context. Heritability estimates for daily milk yield (h2=0.28), lactation length (h2=0.31), and peak yield (h2=0.25) are derived. The dissertation proposes the Bunaji Genomic Improvement Protocol (BGIP) as an original breed improvement framework, specifying reference population maintenance, GEBV update schedules, and dissemination pathways through artificial insemination. Keywords: genomic selection, Bunaji cattle, milk production, North West Nigeria, breeding programme.