Written Paper


María F. Betancur-Zambrano Karen N. Páez-Ordóñes Carlos Solarte-Portilla Edgar Osejo-Rosero Universidad de Nariño [Corporate Author]

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This study was carried out in the high tropic of Nariño, south western of Colombia, in order to construct selection indices for easy application in holstein cattle of this region. Two indices were constructed: the first index with economic weights including the traits of milk yield production (PL), fat (G), and protein (P); and the second index with phenotypic standard deviations of the traits mentioned above, adding the characteristics of type, median suspensory ligament (LIS), foot angle (NAESP) and chest width (ANPEC), given their functional importance in this region. The information was collected in 296 herds, located in the dairy districts of Pasto, Pupiales and Guachucal, which included 50, 133 and 113 farms respectively. Data of milk yield, fat and protein were adjusted to 305 days and mature equivalent. A total of 2372 lactations were evaluated, with an average of 1.98 lactations per animal. The linear evaluation was performed once for national classifiers. The collected data allowed to estimate the values of heritability, repeatability and genetic, phenotypic and environmental correlations of the traits included in the index. For this purpose we used the methodology Animal Model-BLUP, first with the individual analysis of each trait and then with a multitrait model. The basis of economic weights was the system of payment to the producer prices indicated in the Resolution 000012 of 2007, issued by the Ministerio de Agricultura y Desarrollo Rural de
Colombia. The result of joint analysis of genotypic information, phenotypic and economic was an index with the following mathematical expression: I = ((0,0000717253229 × (PL – μPL)) + (0,176940672 × (G – μG)) + (1,03870017 × (P – μP))+ (0,3082605308 × (LIS – μLIS)) + (0,1488063608 × (ANDEP – μANDEP)) + (0,33519556 × (ANPEC –μANPEC))). Because these indices were constructed according to the productive and environmental conditions of the high tropic of Nariño, the use of any of them is recommended as a tool for the selection procedures in this Colombian region, depending on the objectives proposed by each producer.

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Investigación Pecuaria

ISSN : 2248-4558