Feeding distillers grains supplements to improve amino acid nutriture of lambs consuming moderate-quality forages.
We hypothesized that providing dried distillers grains with solubles (DDGS) would improve the N retention and use of nutrients by wethers fed a moderate-quality bromegrass hay. Additionally, we hypothesized that treatment effects on nutrient fluxes would be similar after 3, 6, or 9 wk on treatment. Chronic indwelling catheters were surgically implanted in a mesenteric artery, mesenteric vein, hepatic vein, and portal vein of 9 Suffolk x Dorset wethers (initial BW +/- SD = 57.4 +/- 6.1 kg). Wethers had ad libitum access to moderate-quality bromegrass hay (8.44% CP, DM basis) and received 100 g/d of either a corn-based (Corn, n = 4) or a DDGS-based (n = 5) supplement. There was no difference in DMI (P = 0.85) or DM digestibility (P = 0.46) between the 2 groups. There was a numerically greater N intake (21.5 vs. 18.4 g/d; P = 0.14) and N retention (4.4 vs. 2.5 g/d; P = 0.15) when wethers were supplemented with DDGS instead of Corn. Wethers fed DDGS had a greater (P = 0.008) release of alpha-amino N from the portal-drained viscera (PDV, 37.9 mmol/h) than those fed Corn (14.1 mmol/h). Similarly, there was a shift (P = 0.004) from a net splanchnic uptake to a net release of alpha-amino N in wethers fed DDGS (9.1 mmol/h) compared with those fed Corn (-9.6 mmol/h). However, there was no difference in ammonia release from the PDV (P = 0.49) or hepatic release of urea-N (P = 0.19) between the 2 treatments. There were very limited interactions between nutrient fluxes and the length of time after the initiation of treatments. However, there was a tendency (interaction, P = 0.07) for the PDV release of alpha-amino N to be greater at 6 and 9 wk after the initiation of the treatments than after 3 wk on treatment for wethers fed DDGS, although there was no difference over time for wethers fed the Corn supplement. Additionally, there were changes in numerous nutrient fluxes between 3 and 6 wk after the initiation of treatments regardless of treatment. These data indicate that DDGS is a viable supplement to enhance the nutriture of ruminants consuming moderate-quality forages. Additionally, these data indicate that the effects are discernible after 3 wk on treatment, with modest alterations in nutrient flux after additional time on treatment.
Archibeque
S L
SL
USDA-ARS, US Meat Animal Research Center, Clay Center, NE 68933-0166, USA.
Freetly
H C
HC
Ferrell
C L
CL
D000821:Animal Feed / Q000032:analysis / Q000592:standards*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001835:Body Weight / Q000502:physiology; D031724:Bromus / Q000378:metabolism; D002408:Catheters, Indwelling / Q000662:veterinary; D004044:Dietary Proteins / Q000008:administration & dosage* / Q000378:metabolism; D019587:Dietary Supplements; D004063:Digestion / Q000502:physiology; D004435:Eating / Q000502:physiology; D008297:Male; D009584:Nitrogen / Q000097:blood / Q000378:metabolism*; D012756:Sheep / Q000378:metabolism*; D013997:Time Factors; D003313:Zea mays / Q000378:metabolism
D004044:Dietary Proteins; D009584:Nitrogen