S. SENTURKLU1,2, D. G. LANDBLOM1, K. KOCH3 and G. A. PERRY4
1 North Dakota State University, Dickinson Research Extension Center, 1041 State Ave., Dickinson, 58601 ND, USA
2 Canakkale Onsekiz Mart University, Department of Animal Science, BMYO, Biga, 17200 Canakkale, Turkey
3 North Dakota State University, Northern Crops Institute, Dept. 7400, P.O. Box 6050, Fargo, 58108 ND, USA
4 South Dakota State University, Department of Animal and Range Science, Brookings, 57007 SD, USA
SENTURKLU, S., D. G. LANDBLOM, K. KOCH and G. A. PERRY, 2014. Hay substitution with a field peabased blended RDP-RUP compound supplement fed daily or on alternate days to gestating-lactating beef cows. Bulg. J. Agric. Sci., 20: 933-942
To evaluate a forage mitigation strategy, third trimester beef cows were used to determine the effect on subsequent beef cow performance when 28.1% of forage dry matter (DM) was replaced with a nutrient-dense pelleted rumen degradable protein-rumen undegradable protein supplement (RDP -RUP ) fed daily (D) or on alternate days (Alt-D).In the 111 day study, one hundred seven,3-10 year old beef cows, were randomized to the following treatments: 1) all hay control group ©, 2) hay and strawforagethat was reduced 28% and replaced with a field pea-barley malt sprout-distillers dried grain with solubles supplement (PEA-BMS-DD GS) fedD at 0.25% of initial body weight (BW) or, 3) hay and straw foragethat was reduced 28% and replaced witha PEA-BMS-DD GS fed on Alt-D at 0.50% of initial BW. Control cows consumed 14.1 kg of hay compared to supplemented cows that consumed 8.10 kg hay, 2.03 kg straw, and 1.37 kg of supplement daily for a total of 11.5 kg. The experimental supplement that was fed supplied 61% RDP and 36% RUP . Reducing hay in the experimental diets and replacing it with wheat straw and the PEA-BMS-DD GS supplement fed either D or on ALT-D did not affect ending cow BW, body condition score, fat thickness, pre-breeding estrous cyclicity, reproductive cycle pregnancy, or the total percent of cows pregnant (P > 0.10). Control and Alt-D calf birth weight was heavier than the D supplemented group (P < 0.01). Calfweaning weight and gain did not differ (P > 0.10). Biologically, there was no difference between C and supplemented cows throughout the study and it was determined that one unit of PEA-BMS-DD GS supplement could replace 2.9 units of forage. On average, and on the basis of 100 cows supplemented for the 111 day period, 15.1 mt of supplement replaced 44.1 mt of forage (P<0.001). Compared to feeding the all hay C diet,the cost of replacing hay with wheat straw and the nutrient-dense PEA-BMS-DD GS supplement was $287.54, $304.44, and $302.43 per cow for the C,D, and ALT-D treatments, respectively. The slightly higher cost for supplementation in the drought mitigation strategy tested wasminiscule compared to selling cows to fit the available forage supply. These data suggest that adequate nutrient supply to the rumen and small intestine can be obtained when feeding a PEA-BMSDD GS on ALT-D and that the dietary strategy can be used to mitigate drought related hay shortages.
Key words: beef cows, barley malt sprout, distillers dried grain with solubles, field pea, rumen degradable protein, rumen undegradable protein
Abbreviations: ADF - acid detergent fibre; ADG - average daily gain, Alt-D - alternated days; BCS - body condition score; BMS - barley malt sprout; BW - body weight; C2+ - calcium; C - control group; CP - crude protein; D - daily; DD GS - distillers dried grain with solubles; DM - dry matter; IVDMD - in vitro dry matter disappearance; IVOMD - in vitro organic matter disappearance; NDF - neutral detergent fibre; OM - organic matter; PEA - field pea; PEABMS - DD GS, field pea-barley malt sprout-distillers dried grain with solubles blended supplement; P - phosphorus; PR - pregnancy rate; RDP - rumen degradable protein; RUP - rumen undegradable protein; SF – supplementation frequency; TDN - total digestible nutrients