|Lammers, P - IOWA STATE UNIVERSITY|
|Bregendahl, K - IOWA STATE UNIVERSITY|
|Lonergan, S - IOWA STATE UNIVERSITY|
|Prusa, K - IOWA STATE UNIVERSITY|
|Ahn, D - IOWA STATE UNIVERSITY|
|Dozier Iii, William|
|Honeyman, M - IOWA STATE UNIVERSITY|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 23, 2008
Publication Date: November 1, 2008
Citation: Lammers, P.J., Kerr, B.J., Weber, T.E., Bregendahl, K., Lonergan, S.M., Prusa, K.J., Ahn, D.U., Stoffregen, W.C., Dozier III, W.A., Honeyman, M. 2008. Growth performance, carcass characteristics, meat quality, and tissue histology of growing pigs fed crude glycerin-supplemented diets. Journal of Animal Science. 86(11):2962-2970. Interpretive Summary: With the rapid expansion of the biodiesel industry, there has been a substantial increase in crude glycerol (the principal co-product of biodiesel production) becoming available for use as a feedstuff for swine. Previously, we reported that the apparent metabolizable energy content of crude glycerol (87% glycerol) was 3,207 kcal/kg. The current study evaluated the potential of supplementing 0, 5, or 10% crude glycerin in diets fed to pigs from 8 to 133 kg body weight. The experiment demonstrated that pigs could be fed up to 10% crude glycerol with little to no effect on pig performance, carcass composition, or meat quality indicies. This information is important for nutritionists at universities, feed companies, and swine production facilities showing them the ability to use crude glycerol as a viable feed ingredient in swine diet formulation.
Technical Abstract: Growth performance, carcass characteristics, meat quality indices, and tissue histology of growing pigs fed crude glycerol were determined in a 138-d feeding trial. Crude glycerol utilized in the trial contained 84.51% glycerol, 11.95% water, 2.91% sodium chloride, and 0.32% methanol. Eight days post-weaning, 96 pigs (48 barrows, 48 gilts, average body weight of 7.9 ± 0.4 kg) were allotted to 24 pens (4 pigs/pen), with gender and body weight balanced at the start of the experiment. Dietary treatments were 0, 5, and 10% crude glycerol inclusion into corn-soybean meal based diets and were randomly assigned to each pen. Diets were offered ad libitum in meal form and formulated to be equal in metabolizable energy, sodium, chloride, and lysine, with other amino acids balanced on an ideal amino acid basis. Pigs and feeders were weighed bi-weekly to determine average daily gain and average daily feed intake, with gain:feed calculated. At the end of the trial, all pigs were scanned using real time ultrasound and subsequently processed at a commercial abattoir. Blood samples were collected pre-transport and at the time of harvest for plasma metabolite analysis. In addition, kidney, liver, and eye tissues were collected for subsequent examination for lesions characteristic of methanol toxicity. After an overnight chilling of the carcass, loins were removed for meat quality, sensory evaluation, and fatty acid profile analysis. Pig growth, feed intake, and gain:feed were not affected by dietary treatment. Fatty acid profile of the longissimus muscle was slightly changed by diet with the longissimus muscle from pigs fed 10% crude glycerol having less linoleic acid (P < 0.01) and more eicosapentaenoic acid (P < 0.02) than pigs fed the 0 or 5% crude glycerol treatments. Dietary treatment did not affect blood metabolites or frequency of lesions in the examined tissues. This experiment demonstrates that pigs can be fed up to 10% crude glycerol with little to no effect on pig performance, carcass composition, meat quality, or lesion scores.