A comparison between Poisson and zero-inflated Poisson regression models with an application to number of black spots in Corriedale sheep Hugo Naya, Jorge I. Urioste, Yu-Mei Chang, Mariana Rodrigues-Motta, Roberto Kremer and Daniel GianolaGenet. Sel. Evol., 40 4 (2008) 379-394DOI: https://doi.org/10.1051/gse:2008010