title: Effects of dietary iodine value product on growth performance and carcass fat quality of finishing pigs.
abstract: A total of 120 barrows (initial BW = 47.9 ± 3.6 kg; PIC 1050) were used in an 83-d study to determine the effects of dietary iodine value (IV) product (IVP) on growth performance and fat quality. Pigs were blocked by BW and randomly allotted to 1 of 6 treatments with 2 pigs per pen and 10 pens per treatment. Dietary treatments were fed in 3 phases and formulated to 3 IVP concentrations (low, medium, and high) in each phase. Treatments were 1) corn-soybean meal control diet with no added fat (low IVP), 2) corn-extruded expelled soybean meal (EESM) diet with no added fat (medium IVP), 3) corn-soybean meal diet with 15% distillers dried grains with solubles and choice white grease (DDGS + CWG; medium IVP), 4) corn-soybean meal diet with low CWG (medium IVP), 5) corn-EESM diet with 15% DDGS (high IVP), and 6) corn-soybean meal diet with high CWG (high IVP). On d 83, pigs were slaughtered and backfat and jowl fat samples were collected and analyzed. The calculated and analyzed dietary IVP values were highly correlated (r(2) = 0.86, P < 0.01). Pigs fed the control diet, EESM, or high CWG had greater (P < 0.05) ADG than pigs fed EESM + DDGS. Pigs fed the control diet had greater (P < 0.05) ADFI than pigs fed all other diets. Pigs fed EESM + DDGS and high CWG had improved (P < 0.05) G:F compared with pigs fed the control diet or DDGS + CWG. Pigs fed diets with DDGS had greater (P < 0.05) backfat and jowl fat IV, C18:2n-6, and PUFA and less SFA than pigs fed all other treatments. Pigs fed EESM had greater (P < 0.05) backfat and jowl fat IV, C18:2n-6, and PUFA than pigs fed the control diet, low CWG, or high CWG. Pigs fed low CWG or high CWG had greater (P < 0.05) jowl fat IV than control pigs. Feeding ingredients high in unsaturated fatty acids, such as DDGS and EESM, had a greater impact on fat IV than CWG, even when diet IVP was similar. Therefore, IVP was a poor predictor of carcass fat IV in pigs fed diets with different fat sources and amounts of unsaturated fats formulated with similar IVP. Dietary C18:2n-6 content was a better predictor of carcass fat IV than diet IVP.
authors.affiliation: Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS 66506-0201, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Benz
authors.forename: M D
authors.initials: MD
authors.lastname: Tokach
authors.forename: S S
authors.initials: SS
authors.lastname: Dritz
authors.forename: J L
authors.initials: JL
authors.lastname: Nelssen
authors.forename: J M
authors.initials: JM
authors.lastname: Derouchey
authors.forename: R C
authors.initials: RC
authors.lastname: Sulabo
authors.forename: R D
authors.initials: RD
authors.lastname: Goodband
mesh_terms: D000273:Adipose Tissue / Q000254:growth & development*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001823:Body Composition / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D004041:Dietary Fats / Q000378:metabolism; D005230:Fatty Acids, Nonesterified / Q000032:analysis; D007455:Iodine / Q000008:administration & dosage*; D008297:Male; D011897:Random Allocation; D018709:Statistics, Nonparametric; D013552:Swine / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D004041:Dietary Fats; D005230:Fatty Acids, Nonesterified; D007455:Iodine