Monensin and concentrate supplementation level affect forage ruminal measurements and forage in situ disappearance of bermudagrass fed to beef cattle



      The objective of this study was to evaluate the effects of monensin and concentrate supplementation levels on bermudagrass (Cynodon dactylon) in situ disappearance and ruminal measurements.

      Materials and Methods

      The experiment was conducted in Ona, Florida, and treatments were the factorial arrangement of 2 supplementation levels [0.4 (low) or 4 kg/d (high)] and 2 monensin levels (0 or 20 mg/kg of the DMI) distributed in a Latin square design. The supplement was 17.1% CP and 79.1% TDN.

      Results and Discussion

      Steers receiving the higher supplementation level had greater (P = 0.01) total DMI (1.4 vs. 1.0 ± 0.1% BW), but there was no difference in forage DMI (P = 0.72, mean = 1.0 ± 0.1% BW). Monensin did not affect total DMI or forage DMI (P ≤ 0.74). There was a monensin × supplementation level interaction on ruminal propionate concentration. The interaction occurred because there was no effect (P = 0.64) of monensin with low supplementation (mean = 12 ± 1.2 mol/100 mol); however, monensin increased (P = 0.01) propionate on the high supplementation level (19 vs. 15 ± 1.5 mol/100 mol). There was no effect (P > 0.05) of monensin on potential DM, CP, and NDF disappearance; however, greater supplementation level increased (P < 0.03) potential DM and NDF disappearance.

      Implications and Applications

      Monensin did not change forage disappearance measurements but increased ruminal propionate concentrations in steers receiving higher supplementation level. Higher supplementation level was effective to increase total DMI and forage DM and NDF disappearance.

      Key words

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        • Aguiar A.D.
        • Vendramini J.M.B.
        • Arthington J.D.
        • Sollenberger L.E.
        • DiLorenzo N.
        • Hersom M.
        Performance of beef cows and calves fed different sources of rumen-degradable protein when grazing stockpiled limpograss pastures..
        J. Anim. Sci. 2015; 93: 1923-1932
        • Bergen W.G.
        • Bates D.B.
        Ionophores: Their effect on production efficiency and mode of action..
        J. Anim. Sci. 1984; 58: 1465-1483
        • Broderick G.A.
        • Kang J.H.
        Automated simultaneous determination of ammonia and total amino acids in ruminal fluid and in vitro media..
        J. Dairy Sci. 1980; 63: 64-75
        • Brutti D.D.
        • de Paula N.F.
        • Zervoudakis J.T.
        • Cabral L.S.
        • Fonseca M.A.
        • Macedo B.G.
        • Lima L.R.
        Effects of tannins and monensin on the modulation of in vitro ruminal fermentation and ammonia production of nitrogen-fertilized and non-fertilized Urochloa brizantha cv. Marandu..
        Grassl. Sci. 2019; 65: 101-108
        • Cooke R.F.
        • Daigle C.L.
        • Moriel P.
        • Smith S.B.
        • Tedeschi L.O.
        • Vendramini J.M.B.
        Cattle adapted to tropical and subtropical environments: Social, nutritional, and carcass quality considerations..
        J. Anim. Sci. 2020; 98
        • Duffield T.F.
        • Rabiee A.R.
        • Lean I.J.
        A meta-analysis of the impact of monensin in lactating dairy cattle. Part 1. Metabolic effects..
        J. Dairy Sci. 2008; 91: 1334-1346
      1. Ellis, W. C., J. H. Matis, T. M. Hill, and M. R. Murphy. 1994. Methodology for estimating digestion and passage kinetics of forages. G. C. Fahey, ed. Pages 682–756 in Forage Quality, Evaluation, and Utilization. University of Nebraska, Lincoln.

        • Gallaher R.N.
        • Weldon C.O.
        • Futral J.G.
        An aluminum block digester for plant and soil analysis..
        Soil Sci. Soc. Am. J. 1975; 39: 803-806
        • Granja-Salcedo Y.T.
        • Ribeiro Júnior C.S.
        • de Jesus R.B.
        • Gomez-Insuasti A.S.
        • Rivera A.R.
        • Messana J.D.
        • Canesin R.C.
        • Berchielli T.T.
        Effect of different levels of concentrate on ruminal microorganisms and rumen fermentation in Nellore steers..
        Arch. Anim. Nutr. 2016; 70: 17-32
      2. Hammond, A. C. 1997. Update on PUN and MUN as a guide for protein supplementation in cattle. Pages 43–52 in Proc. Florida Rumin. Nutr. Symp. Univ. of Florida, Gainesville.

        • Harmon D.L.
        • Kreikemeier K.K.
        • Gross K.L.
        Influence of addition of monensin to an alfalfa hay diet on net portal and hepatic nutrient flux in steers..
        J. Anim. Sci. 1993; 71: 218-225
      3. Horn, G. W., and F. T. McCollum. 1987. Energy supplementation of grazing ruminants. Pages 125–136 in Proc. Grazing Livestock Nutrition Conference, Jackson Hole, WY. M. B. Judkins, D. C. Clanton, M. K. Petersen, and J. D. Wallace, ed. Sponsored by the Univ. Wyoming.

        • Kang-Meznarich J.H.
        • Broderick G.A.
        Effects of incremental urea supplementation on ruminal ammonia concentration and bacterial protein formation..
        J. Anim. Sci. 1980; 51: 422-431
        • Kolver E.S.
        • de Veth M.J.
        Prediction of ruminal pH from pasture-based diets..
        J. Dairy Sci. 2002; 85: 1255-1266
        • Krishnamoorthy U.
        • Sniffen C.J.
        • Stern M.D.
        • Van Soest P.
        Evaluation of mathematical model of rumen digestion and an in vivo simulation of rumen proteolysis to estimate the rumen-undegraded nitrogen content of feedstuffs..
        Br. J. Nutr. 1983; 50: 555-568
        • Lemenager R.P.
        • Owens F.N.
        • Shockey B.J.
        • Lusby K.S.
        • Totusek R.
        Monensin effects on rumen turnover rate, twenty-four hour VFA pattern, nitrogen components and cellulose disappearance..
        J. Anim. Sci. 1978; 47: 255-261
        • Martinez C.M.
        • Chung Y.H.
        • Ishler V.A.
        • Bailey K.W.
        • Varga G.A.
        Effects of dietary forage level and monensin on lactation performance, digestibility and fecal excretion of nutrients, and efficiency of feed nitrogen utilization of Holstein dairy cows..
        J. Dairy Sci. 2009; 92: 3211-3221
      4. Minson, D. J. 1990. Forage in Ruminant Nutrition. Academic Press.

        • Moriel P.
        • Cooke R.F.
        • Bohnert D.W.
        • Vendramini J.M.B.
        • Arthington J.D.
        Effects of energy supplementation frequency and forage quality on performance, reproductive, and physiological responses of replacement beef heifers..
        J. Anim. Sci. 2012; 90: 2371-2380
        • Moriel P.
        • Scatena T.S.
        • Sá Filho O.G.
        • Cooke R.F.
        • Vasconcelos J.F.M.
        Concentrations of progesterone and insulin in serum of non-lactating dairy cows in response to carbohydrate source and processing..
        J. Dairy Sci. 2008; 91: 4616-4621
        • Moriel P.
        • Vendramini J.M.B.
        • Carnelos C.
        • Piccolo M.B.
        • da Silva H.M.
        Effects of monensin on growth and performance of beef heifers consuming warm-season perennial grass and supplemented with sugarcane molasses..
        Trop. Anim. Health Prod. 2019; 51: 339-344
        • Muntifering R.B.
        • Theurer B.
        • Swingle R.S.
        • Hale W.H.
        Effect of monensin on nitrogen utilization and digestibility of concentrate diet by steers..
        J. Anim. Sci. 1980; 50: 930-936
        • Oba M.
        • Allen M.S.
        Evaluation of the importance of the digestibility of neutral detergent fiber from forage: effects on dry matter intake and milk yield of dairy cows..
        J. Dairy Sci. 1999; 82: 589-596
        • Oliveira R.A.
        • Moriel P.
        • Vendramini J.M.B.
        • da Silva H.M.
        • Vedovatto M.
        • Neiva J.N.M.
        • Miotto F.R.C.
        • Miranda M.
        • da Silva D.P.
        Supplemental monensin affects growth, physiology, and coccidiosis infestation of early-weaned beef calves consuming warm-season perennial or cool-season annual grasses..
        Appl. Anim. Sci. 2020; 36: 108-117
        • Ørskov E.R.
        • McDonald D.C.
        The estimation of protein degradability in the rumen from incubation measurements weighted according to rate of passage..
        J. Agric. Sci. 1979; 92: 499-503
        • Oscar T.P.
        • Spears J.W.
        • Shih J.C.H.
        Performance, methanogenesis and nitrogen metabolism of finishing steers fed monensin and nickel..
        J. Anim. Sci. 1987; 64: 887-896
      5. Pond, K. P., and W. C. Ellis. 1981. Effects of monensin on fecal output and voluntary intake of grazed coastal bermudagrass. Page 31 in Beef Cattle Research in Texas. Texas Agric. Exp. Sta., College Station, TX.

        • Poos M.I.
        • Hanson T.L.
        • Klopfenstein T.J.
        Monensin effects on diet digestibility, ruminal protein bypass and microbial protein synthesis..
        J. Anim. Sci. 1979; 48: 1516-1524
      6. Rowe, J. B., P. J. Murray, and S. L. Godfrey. 1991. Manipulation of the fermentation and digestion to optimize the use of forage resources for ruminant production. Pages 83–99 in Isotope and Related Techniques in Animal Production and Health. International Atomic Energy Agency.

        • Russell J.B.
        A proposed mechanism of monensin action in inhibiting ruminal bacteria growth: Effects on ion flux and protonmotive force..
        J. Anim. Sci. 1987; 64: 1519-1525
        • Sollenberger L.E.
        • Vanzant E.
        Interrelationships among forage nutritive value and quantity and individual animal performance..
        Crop Sci. 2011; 51: 420-432
        • Vagnoni D.B.
        • Craig W.M.
        • Gates R.N.
        • Wyatt W.E.
        • Southern L.L.
        Monensin and ammoniation or urea supplementation of bermudagrass diets for steers..
        J. Anim. Sci. 1995; 73: 1793-1802
        • Van Soest P.J.
        • Robertson J.B.
        • Lewis B.A.
        Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition..
        J. Dairy Sci. 1991; 74: 3583-3597
        • Vanzant E.S.
        • Cochran R.C.
        • Titgemeyer E.C.
        Standardization of in situ techniques for ruminant feedstuff evaluation..
        J. Anim. Sci. 1998; 76: 2717-2729
        • Vendramini J.M.B.
        • Moriel P.
        • Cooke R.F.
        • Arthington J.D.
        • da Silva H.M.
        • Piccolo M.B.
        • Sanchez J.M.D.
        • Gomes V.
        • Mamede P.A.
        Effects of monensin inclusion into increasing amount of concentrate on growth and physiological parameters of early-weaned beef calves consuming warm-season grasses..
        J. Anim. Sci. 2018; 96: 5112-5123
        • Vendramini J.M.B.
        • Sanchez J.D.
        • Cooke R.F.
        • Aguiar A.D.
        • Moriel P.
        • da Silva W.L.
        • Cunha O.F.R.
        • Ferreira P.D.S.
        • Pereira A.C.
        Stocking rate and monensin supplementation effects on performance of beef cattle consuming warm-season grasses..
        J. Anim. Sci. 2015; 93: 3682-3689
        • Weiss W.P.
        • Conrad H.R.
        • St. Pierre N.R.
        A theoretically-based model for predicting total digestible nutrient values of forages and concentrates..
        Anim. Feed Sci. Technol. 1992; 39: 95-110