Association of SNPs in the genes for κ‑casein and β‑lactoglobulin with lactation curves in dairy goats

Abstract

The objective of this work was to identify the model that best fits production data of milk, fat, protein, and total solids for dairy goats, as well as to associate single‑nucleotide polymorphisms (SNPs) in the genes for κ‑casein (κ‑CSN3) and β‑lactoglobulin (β‑LG) with parameters from lactation and milk‑quality curves. A total of 4,160 production records of milk, fat, protein, and total solids from goats of the Alpine, Saanen, and crossbred breeds, in the state of Antioquia, Colombia, were evaluated. The nonlinear models with the best fit to data structure were Nelder’s, for milk yield, and Cappio‑Borlino’s, for milk quality. Association analyzes showed significant effect of the SNP κ‑CSN3 on production peak, initial production, and persistence of milk‑quality traits. The SNP β‑LG had significant effect on the peaks of milk and fat yield, and on the time required to reach the peak of protein yield. The identification and estimation of the influence of the evaluated SNP markers on lactation and milk‑quality curves can contribute for dairy goat selection.