ROBO2 Gene Variation and Experimental Newcastle Disease Response Across Three Nigerian Indigenous Chicken Genotypes

Description

Nigeria’s poultry industry faces significant economic threats from Newcastle Disease Virus (NDV), characterized by high mortality rates even in vaccinated flocks. This research investigated the genetic resistance and potential of single nucleotide polymorphisms (SNPs) in the Roundabout guidance receptor homolog 2 (ROBO2) gene to enhance resistance. Three indigenous chicken genotypes Normal, Frizzle, and Naked Neck (totaling 180 chicks) were challenged with the velogenic NDV Kudu 113 strain. While vaccination improved resistance, the Naked Neck genotype exhibited superior resilience with the lowest mortality (79%) compared to Frizzle (100%) and Normal (94%), possibly due to enhanced acute phase protein secretion. One non-synonymous SNP (98C>A) in exon 3 of the ROBO2 gene significantly influenced antibody responses, revealing a robust genetic marker. Naked Neck individuals consistently showed the highest immune responses, measured by antibody titers, indicating their suitability for genetic improvement programs against NDV. This research offers valuable insights for selective breeding to counteract widespread NDV threats in West Africa.