0
Crossbreed piglets weaned at 21 d of age were fed with a commercial starter diet for 1 wk. Eight days post-weaning, 96 pigs (48 barrows and 48 gilts, average BW of 7.9 ± 0.4 kg) were allotted to 24 pens (4 pigs/pen), with sex and BW balanced at the start of the experiment. Experimental dietary treatments consisted of 0, 5, and 10% crude glycerin inclusion in a corn-soybean meal-based diets which were randomly assigned to pens. Diets were offered ad libitum in mash form. Pigs and feeders were weekly weighed to determine ADG, ADFI, and G:F. At the end of the trial, all pigs were scanned using real-time ultrasound and subsequently slaughtered at a commercial abattoir. Blood samples were collected pre-transport and at the time of slaughter 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.
No effects were observed on ADG, ADFI, and G:F due to the dietary treatments in any the different phases or over the entire 138-d experimental period. Carcass characteristics at the 10th-rib backfat, LM area, fat-free lean; daily lean gain and carcass lean percentage were neither affected by the experimental treatments. Diet did not affect percent loin lean, moisture content, or chop lipid percentage. Loin ultimate pH was increased (P = 0.06) in pigs fed the 5 and 10% crude glycerin compared with pigs fed no crude glycerin. Loin tissue from pigs fed 10% crude glycerin had lower linoleic acid (18:2) concentrations than the other dietary treatments, however eicosapentaenoic acid (20:5) increased by increasing the crude glycerin supplementation. Pork loin quality and sensory characteristics were not affected by diet. Additionally, no effect was observed on plasma metabolite measured. Frequency of histological lesions in kidney, liver, and eye, the pharmacological targets for methanol toxicity, were not influenced by dietary treatment.
It is concluded that up to 10% of crude glycerin can be fed to growing-finishing pigs without affecting growth performance, carcass composition, meat quality, or lesion scores in the eye, liver, or kidney tissue.
PJ Lammers, BJ Kerr, TE Weber, K Bregendahl, SM Lonergan, KJ Prusa, DU Ahn, WC Stoffregen, WA Dozier and MS Honeyman. 2008. Journal of Animal Science, 86:2962-2970.
