Análisis comparativo de los grupos genéticos Holstein, Jersey y algunos de sus cruces en un hato lechero del Norte de Antioquia en Colombia

the dairy sector in colombia has increased its development in recent years and is important in terms of its contribution to total gross domestic product. genetic groups that have the largest inventory are holstein and jersey, they have the largest volume of production and higher percentage of milk components, respectively. the aim of this study was to compare the genetic groups holstein and jersey and some of its crosses and evaluate productive, reproductive and economic performance. the study was conducted in a dairy herd located in the municipality of belmira (antioquia), which had historic production information of seven years preceding the survey. we used a total of 582 animals with 2,316 lactations distributed as follows: holstein, jersey, f1 holstein x jersey, 75% holstein and 75% jersey. the differences between the parameters productive, reproductive and economic of each genetic group were analyzed using proc glm of sas. jersey 75% animals had the highest income due to improved milk composition in terms of percentage of protein and fat, to lower production costs and the number of kids sold per year. jersey 75% of individuals should be considered when defining the racial composition of livestock holdings. these findings raise a very interesting knowledge about the genetic approach to be given to farming in colombia. however, further research is recommended to increase the reliability of the results.