Nutritional evaluation of poultry by-product meal as a protein source for ruminants: effects on performance and nutrient flow and disappearance in steers.
We conducted three studies with steers to evaluate poultry by-product meal (PBM) as a supplemental N source for ruminants. An in situ study compared the solubility, degradation rate, and ruminal escape of PBM N with blood meal (BM), corn gluten meal (CGM), and soybean meal (SBM) N. Additionally, an 84-d growth study (n = 95, 228+/-5 kg BW) and a digestion trial (6 x 6 Latin square) were conducted. The basal diet for the growth and digestion studies consisted of 49% corn silage, 36% cottonseed hulls, and 15% supplement (DM basis). Sources of supplemental N (% of total supplemental N) were 100% SBM and 0, 25, 50, 75, and 100% PBM, with urea used to balance for N. In situ ruminal escape N (25.2, 55.3, 86.7, and 98.9% for SBM, PBM, CGM, and BM, respectively) was greater (P < .05) for PBM than for SBM; however, a greater (P < .05) proportion of BM and CGM N escaped ruminal degradation compared with PBM. Dry matter intake, ADG and gain/ feed increased linearly (P < .003) as PBM increased; however, no differences (P > .48) were observed in these variables for 100% PBM compared with 100% SBM. Duodenal N flow and small intestinal N disappearance increased linearly (P < .05) as PBM increased in the diet. Bacterial N flow to the small intestine was not affected (P > .19) by treatment; however, 100% SBM decreased (P < .04) bacterial CP synthesis (g bacterial N/kg OM disappearance from the stomach) compared with 0 and 100% PBM. In vivo ruminal escape N of PBM and SBM was 40.6 and 13.7%, respectively. Ruminal NH3 N decreased linearly (P < .001) as PBM increased. These data suggest that PBM can replace SBM as a source of supplemental N for steer calves that consume a diet based on corn silage and cottonseed hulls.
Bohnert
D W
DW
Department of Animal Sciences, University of Kentucky, Lexington 40546-0215, USA.
Larson
B T
BT
Bauer
M L
ML
Branco
A F
AF
McLeod
K R
KR
Harmon
D L
DL
Mitchell
G E
GE
D000641:Ammonia / Q000378:metabolism; D000821:Animal Feed / Q000592:standards*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001426:Bacterial Proteins / Q000096:biosynthesis; D001769:Blood; D002417:Cattle / Q000254:growth & development* / Q000502:physiology; D003369:Cottonseed Oil; D004044:Dietary Proteins / Q000592:standards*; D004063:Digestion; D004386:Duodenum / Q000502:physiology; D004435:Eating; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005983:Glutens; D007082:Ileum / Q000502:physiology; D008297:Male; D009584:Nitrogen / Q000378:metabolism; D009753:Nutritive Value; D011202:Poultry Products / Q000592:standards*; D011897:Random Allocation; D012417:Rumen / Q000502:physiology; D013025:Glycine max; D015430:Weight Gain; D003313:Zea mays
D001426:Bacterial Proteins; D003369:Cottonseed Oil; D004044:Dietary Proteins; D005232:Fatty Acids, Volatile; D000641:Ammonia; D005983:Glutens; D009584:Nitrogen