Document Type : Research Paper
Authors
1
Ph.D. Candidate, Department of Animal Science, Tabriz University, Tabriz, Iran
2
Assistant Professor, Department of Animal Science, Faculty of Agriculture, Tabriz University, Tabriz, Iran
3
Professor, Department of Animal Science, Faculty of Agriculture, Isfahan University of Technology, Isfahan, Iran
4
Professor, Department of Animal Science, Faculty of Agriculture, Tabriz University, Tabriz, Iran
5
Associate Professor, Department of Animal Science, Faculty of Agriculture, Tabriz University, Tabriz, Iran
Abstract
This study was conducted to investigate the effects of replacement of soybean meal with canola meal and corn processing on productive performance of Holstein dairy cows. Twelve Holstein cows (milk yield= 46±3 kg/d) were assigned to a replicated 4×4 Latin square design with a 2×2 factorial arrangement of treatments. Factor 1 was corn processing method, ground corn or steam flaked corn, and factor 2 was two ratio canola meal to soybean meal (50:50 or 100:0). No significant interactions of main treatment effects occurred for lactation performance data. Dry matter intake and milk production was not affected by replacement of soybean meal with canola meal. Milk compounds concentration was not affected by this replacement. Substitution of hundred percent of soybean meal with canola meal in the diet decreased the apparent digestibility of the dry matter. Feed intake was decrease when the cows received steam flaked corn compared with those receiving ground corn. Milk fat content decreased but milk protein content increased in cows fed steam flaked compared with those fed ground corn. Although these results showed no interaction effects of replacement of soybean meal with canola meal and corn processing method on performance, higher canola meal ratio and steam flaked corn improved feed efficiency and has a positive effect on the metabolism of nitrogen and energy, so recommended to fed in high-yielding cows under the conditions of this experiment.
Keywords