Avian Infectious Bronchitis (IAB) is a viral disease that generates great economic losses in the poultry industry. Due to its structural components and particular immunogenic characteristics, the IB virus, the chicken coronavirus (Gallus gallus), has generated a great challenge for its control, given the emergence of different genotypes with global distribution with changing clinical manifestations. This has generated interest in the study and analysis of the dynamics of the phylogenetic evolution of the virus, as well as the impact on immunological activity, requiring the development of new vaccine strains based on the high variability of the S1 gene portion 1. In the present review, updated information on the phylogenetic evolution of IAV was compiled and the impact on the immunogenic response in poultry production systems is analysed.

The aim of this study was to analyse the gene and genotypic parameters using microsatellites of Creole bovine (CB) from the high southern tropics of Ecuador and contrasting them with registered Holstein bovine (HB); For this, blood was collected from 7 CC and 3 BC subpopulations. Fifteen markers grouped into 4 mixtures were analysed; 1) CSRM60, INRA083, CSSM66; 2) ETH3, HEL9, TGLA53, BM1818, ILSTS006; 3) BM2113, ETH225, TGLA122, ETH10; and 4) TGLA227, INRA032, SPS115. Genetic variation parameters were determined: number of alleles (Na), number of effective alleles (Ne), frequency of null alleles (f-Null), observed heterozygosity (Ho) and expected (He), Polymorphism Information Content (PIC), inbreeding coefficients (Fis), Hardy-Weinberg equilibrium (HWe). In addition, a dendrogram was constructed based on Nei’s distances and identities, and finally, the AMOVA multilocus analysis. In mo...