Location: Agroecosystems Management ResearchTitle: Digestibility of energy and lipids and oxidative stress in nursery pigs fed commercially available lipids
|Lindblom, Stephanie - IOWA STATE UNIVERSITY|
|Dozier, William - AUBURN UNIVERSITY|
|Shurson, Gerald - UNIVERSITY OF MINNESOTA|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/27/2016
Publication Date: 2/11/2017
Citation: Lindblom, S.C., Dozier, W.A., Shurson, G.C., Kerr, B.J. 2017. Digestibility of energy and lipids and oxidative stress in nursery pigs fed commercially available lipids. Journal of Animal Science. 95(1):239-247. doi: 10.2527/jas.2016.0915.
Interpretive Summary: Soybean oil, palm oil, choice white grease, and distillers corn oil (DCO) are major lipid sources used in swine feeding programs, providing a concentrated source of energy compared to other commonly used feedstuffs. The digestibility and caloric value of refined, deodorized, bleached corn oil and soybean oil have been documented in swine, but there is limited data on the lipid digestibility and energy evaluation of DCO and palm oil. The current study was conducted to evaluate the metabolizable energy content of DCO samples varying in free fatty acid content compared to other major lipid sources used in swine feeding programs. Data from this experiment provided empirical data on the metabolizable energy levels of two different DCO samples and indicates that DCO is a good source of energy for pigs, being approximately 86% of the value for soybean oil, 94% of the value for choice white grease, and 97% of the value for palm oil. This information is important for nutritionists at universities, feed companies, and pig production facilities for the determination of the energy value of commonly used lipids in feed formulations, and provides a basis from which to assess their economic value.
Technical Abstract: An experiment was conducted to evaluate the impact of lipid source on GE and ether extract (EE) digestibility, oxidative stress, and gut integrity in nursery pigs fed diets containing 10% of soybean oil (SO), choice white grease (CWG), palm oil (PO), or 2 different distillers corn oils (DCO-1 and DCO-2). Fifty-four barrows weaned at 28-d of age were fed a common starter diet for 7-d, group-fed their respective experimental diets for an additional 7-d, and then moved to metabolism crates and individually fed their respective diets for another 10-d. Following this period, a 4-d total fecal and urine collection period was used to determine apparent total tract digestibility (ATTD) of gross energy (GE) and EE, and to determine the digestible energy (DE) and metabolizable energy (ME) content of each lipid source (final body weight (BW) 11.03 ± 0.51 kg). Following the last day of fecal and urine collection, pigs were given an oral dose of lactulose and mannitol and fed their respective experimental diets to collect urine collected for 12 h. A subsequent urine collection occurred for 5 h later to determine thiobarbituric acid reactive substances (TBARS) and isoprostane (IsoP) concentrations. Following this urine collection, serum was obtained and analyzed for TBARS and endotoxin concentrations. Soybean oil had the greatest (P < 0.05) DE (9,388 kcal/kg) content compared to DCO1, DCO2, CWG, PO, and SO (8,001, 8,052, 8,531, 8,293, and 9,388 kcal/kg lipid, respectively). Energy digestibility was greatest for SO compared with the other lipid sources (P < 0.05). The ATTD of EE averaged 85.0% and varied slightly (84.4% to 85.6%) among treatments. Differences in ME content among lipids were similar to those reported for DE, with ME values for DCO1, DCO2, CWG, PO, and SO being 7,921, 7,955, 8,535, 8,350, and 9,408 kcal/kg lipid, respectively. Metabolizable energy as a percentage of DE did not differ among lipid sources. Pigs fed lipid diets had greater (P < 0.05) serum TBARS compared with pigs fed the control diet, but no differences were observed in urinary TBARS excretion among the lipid treatments. Urinary IsoP excretion differed among treatments (P < 0.01), but was highly variable (34.0 to 104.6 pg). However, no differences were observed among treatments for urinary lactulose:mannitol ratio and serum endotoxin. These results indicate that DE and ME content of SO are greater than all other lipid sources, but feeding these lipids have no effect on gut integrity while producing variable effects on oxidative stress.