Degree Type


Date of Award


Degree Name

Doctor of Philosophy


Animal Science

First Advisor

Dean R. Zimmerman


Corn gluten feed (CGF) was evaluated as the primary energy and protein source for gestating sows. Eighty multiparous sows were assigned to three treatment groups for the three-parity trial. The gestation treatment diets were: corn-soybean meal fed at 1.8 kg · d[superscript] -1 (control), CGF plus soybean meal fed at 2.3 kg · d[superscript]-1 (CGF-low), and CGF plus soybean meal fed at 2.6 kg · d[superscript] -1 (CGF-high). The CGF diets (>92% CGF) were based on the assumption that CGF had 80% and 70% the energy of corn, respectively. Treatment diets were increased 25% during winter. Sow reproductive performance was excellent for all treatments. Total live pigs at birth and 21 d for the three parities were not significantly different. Pigs from CGF-fed sows were smaller at birth (P <.05), but subsequent pig weights did not differ. For the third parity, the CGF-low sows weighed less at breeding (P <.10), before farrowing (P <.01), after farrowing (P <.05), and at the subsequent breeding (P <.01). On the basis of the sow weights, CGF is equal to 70% the energy value of corn for sows;The energy value of CGF and apparent digestibility coefficients (ADC) of its components were determined using seven multiparous sows (d 60-75 gestation) in metabolism stalls. The diet was 97% CGF fed at 2.6 kg · d[superscript]-1. Determined CGF energy values were: 3552 kcal/kg DE, (12.5% CV), 3308 kcal/kg ME, (16.9% CV), and 3244 kcal/kg ME[subscript] n (14.6% CV). CGF ADCs were: N, 72.3% (27 SEM); EE, 35.4% (29 SEM); NDF, 51.6% (22 SEM); ADF, 47.4% (21 SEM); cellulose, 54.3% (16 SEM); and hemicellulose, 51% (26 SEM);Two trials, each with six multiparous sows in 6 x 6 Latin square designs, were used to determine the required LYS or TRP supplementation of CGF diets. Sows (d 30 gestation) in metabolism stalls were fed 2.6 kg · d[superscript]-1 (97% CGF). Graded levels of supplemental amino acids in Trial 1 were 0,.55, 1.09, 1.65, 2.19, and 2.73 g · d[superscript]-1 LYS and in Trial 2 were 0,.28,.59,.91, 1.19, and 1.50 g · d[superscript]-1 TRP. In Trial 1, increasing LYS intakes decreased (P <.10) urine urea N (quadratic) and fasting plasma urea N (linear) and increased (P <.10) postprandial plasma LYS (quadratic). In Trial 2, increasing TRP intakes linearly increased fasting (P <.01) and postprandial (P <.0001) plasma TRP. CGF can meet or nearly meet the LYS, TRP, and energy needs of gestating sows and current values underestimate the contribution of CGF in sow diets.



Digital Repository @ Iowa State University,

Copyright Owner

Mark Snyder Honeyman



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125 pages