Recent research indicated that the physical properties of maize kernels may be used to evaluate its nutritional value. Therefore, the main objective was to determine the relationships between kernel physical properties and metabolizable energy (ME) for pigs in commercial maize hybrids widely grown in Croatia. Field experiment was conducted in Baranja over two growing seasons with 11 maize hybrids (six domestic hybrids from Bc Institute and five introduced Pioneer hybrids). Investigated hybrids belonged to various maturity groups (FAO 200-600). Growing season significantly affected kernel thickness, kernel length, test weight and ME for pigs, despite similar average 1000-kernel weight in both years of field research. Hybrids differed signifiantly in kernel length, kernel width, kernel thickness, test weight and 1000-kernel weight as well as in ME. The shortest-season hybrid Bc282 had the smallest 1000-kernel weight (on average 314 g), but the largest test weight (on average 79.8 kg/hl) and high ME (on average 16.70 MJ/kg). The smallest test weight and ME was found for hybrid PR36K67 (FAO 490) which had the highest kernel length (13.4 mm on average) and 1000-kernel weight (438g on average), and consequently, low kernel sphericity. Test weight weakly correlated with kernel thickness and kernel sphericity, while it positively correlated with ME. The highest ME had hybrids Bc 572, Bc 462 and PR34B23, while five hybrids had slightly lower values. Of all kernel physical properties, the test weight appears to be most reliable indicator for assessing ME for pigs in the kernels of commercial maize hybrids.

maize, hybrid metabolizable energy, test weight, 1000 kernel weight, kernel size

Published by University of Zagreb, Faculty of Agriculture, Zagreb, CROATIA
Sponsored by Ministry Science and Education of the Republic of Croatia