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Digestion, rumen fermentation and circulating concentrations of insulin, growth hormone and IGF-1 in steers fed diets based on different proportions of maize silage and grass silage

  • D. T. Juniper (a1), E. M. Browne (a1), M. J. Bryant (a1) and D. E. Beever (a1)


Replacing grass silage with maize silage results in a fundamental change in the ratio of structural to non-structural carbohydrates with commensurate changes in rumen fermentation patterns and nutrient utilisation. This study investigated the effects of feeding four forage mixtures, namely grass silage (G); 67 g/100 g grass silage + 33 g/100 g maize silage (GGM); 67 g/100 g maize silage + 33/100 g grass silage (MMG); maize silage (M) to four ruminally and duodenally canulated Holstein Friesian steers. All diets were formulated to be isonitrogenous (22.4 g N/kg DM) using a concentrate mixture. Dietary dry matter (DM) and organic matter (OM) digestibility increased with ascending maize silage inclusion (P < 0.1) whereas starch and neutral detergent fibre digestibility declined (P < 0.05). Ratio of non-glucogenic to glucogenic precursors in the rumen fluid increased with maize silage inclusion (P < 0.01) with a commensurate reduction in rumen pH (P < 0.05). Mean circulating concentrations of insulin were greatest and similar in diets MMG and GGM, lower in diet M and lowest in diet G (P < 0.01). There were no effects of diet on the mean circulating concentration of growth hormone (GH), or the frequency, amplitude and duration of GH pulses, or the mean circulating concentrations of IGF-1. Increasing levels of DM, OM and starch intakes with the substitution of grass silage with maize silage affected overall digestion, nutrient partitioning and subsequent circulating concentrations of insulin.


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Bass, JJ, Spencer, GSG, Hodgkinson, SC 1992. Nutritional control of the growth hormone axis. In The control of fat and lean deposition (ed. PJ Buttery, KN Boorman and DB Lindsay), pp. 175195. Butterworth-Heinemann, Oxford.
Beever, DE, Kellaway, RC, Thompson, DJ, MacRae, JC, Evans, CC, Wallace, AS 1978. A comparison of two non-radioactive digesta marker systems for the measurement of nutrient flow at the proximal duodenum of calves. Journal of Agricultural Science 90, 157163.
Brier, BH 1999. Regulation of protein and energy metabolism by the somatotrophic axis. Domestic Animal Endocrinology 17, 209218.
Browne, EM, Juniper, DT, Bryant, MJ, Beever, DE 2005. Apparent digestibility and nitrogen utilisation of diets based on maize and grass silage fed to beef steers. Animal Feed Science and Technology 119, 5568.
Cecava, MJ 1995. Rumen physiology and energy requirements. In Beef cattle feeding and nutrition, 2nd edition (ed. TW Perry and MJ Cecava). Academic Press, London, UK.
Cone, JW, ClineThiel, W, Malestein, A, van’t Klooster, AT 1989. Degradation of starch by incubation with rumen fluid. A comparison of different starch sources. Journal of the Science of Food and Agriculture 49, 173183.
Deaville, ER, Givens, DI 1995. Extent of variation in cell wall degradation of forages in ruminants. In Grassland into the 21st century: challenges and opportunities, pp. 250–252. British Grassland Society, Reading, UK.
DePeters, EJ, Taylor, SJ 1985. Effects of feeding corn or barley on composition of milk and diet digestibility. Journal of Dairy Science 68, 20272032.
Downes, AM, McDonald, IW 1964. The chromium-51 complex of ethylenediamine tetraacetic acid as soluble rumen marker. British Journal of Nutrition 18, 153162.
Echternkamp, SE, Spicer, LJ, Gregory, KE, Canning, SF, Hammond, JM 1990. Concentrations of insulin like growth factor-1 in blood and ovarian follicular fluid of cattle selected for twins. Biology of Reproduction 43, 814.
Elizalde, JC, Merchen, NR, Faulkner, DB 1999. Supplemental cracked corn for steers fed fresh Alfalfa: I. Effects on digestion of organic matter, fiber and starch. Journal of Animal Science 77, 457466.
Elsasser, TH, Rumsy, TS, Hammond, AC 1989. Influence of diet on basal and growth hormone stimulated plasma concentrations of IGF-1 in beef cattle. Journal of Animal Science 67, 128141.
Faichney, GJ 1975. The use of markers to partition digestion within the gastrointestinal tract of ruminants. In Digestion and Metabolism in the Ruminant (ed. IW McDonald and ACI Warner), pp. 277291. University of New England Publishing Unit, Armidale, New South Wales, Australia.
Friggens, NC, Oldham, JD, Dewhurst, RJ, Horgan, G 1998. Proportions of volatile fatty acids in relation to the chemical composition of feeds based on grass silage. Journal of Dairy Science 81, 13311344.
Hart, IC, Flux, DS, Andrews, P, McNeilly, AS 1975. Radioimmunoassay for ovine and caprine growth hormone: its application to the measurement of basal circulating levels of growth hormone in the goat. Hormone and Metabolic Research 7, 3540.
Juniper, DT, Browne, EM, Fisher, AV, Bryant, MJ, Nute, GR, Beever, DE 2005. Intake, growth and meat quality of steers given diets based on varying proportions of maize silage and grass silage. Animal Science 81, 159170.
Juniper, DT, Browne, EM, Bryant, MJ, Beever, DE 2006. Digestion, rumen fermentation and circulating concentrations of insulin, growth hormone and IGF-1 in steers given maize silages harvested at three stages of maturity. Animal Science 82, 4148.
Kung, L, Tung, RS, Carmean, BR 1992. Rumen fermentation and nutrient digestion in cattle fed diets varying in forage and energy source. Animal Feed Science and Technology 39, 112.
MacRae, JC, Armstrong, DG 1968. Studies on intestinal digestion in sheep: digestion of some carbohydrate constituents in hay, cereal and hay rations. British Journal of Nutrition 23, 377387.
Merriam, GR, Wachter, KW 1982. Algorithms for the study of episodic hormone secretion. American Journal of Physiology 243, 310318.
Mertens, DR, Loften, JR 1980. The effect of starch on fiber digestion kinetics in vitro. Journal of Dairy Science 63, 14371446.
Ministry of Agriculture, Fisheries and Food 1983. The analysis of agricultural materials, MAFF reference book, 427. HMSO, London, UK.
Ministry of Agriculture, Fisheries and Food 1993. Prediction of the energy values of compound feeding stuffs for farm animals. MAFF Publications, London, UK.
Mould, FL, Orskov, ER, Mann, SO 1983. Associative effects of mixed feeds. I. Effects of type and level of supplementation and the influence of rumen fluid pH on cellulolysis in vivo and dry matter digestion of various roughages. Animal Feed Science and Technology 10, 1530.
Overton, TR, Cameron, MR, Elliot, JP, Clark, JH, Nelson, DR 1995. Ruminal fermentation and passage of nutrients to the duodenum of lactating dairy cows fed mixtures of corn and barley. Journal of Dairy Science 78, 19811998.
Porter, MG, Patterson, DC, Steen, RWJ, Gordon, FJ 1984. Determination of dry matter and gross energy of grass silage. In Proceedings of the 7th Silage Conference on Silage Production and Utilization, Belfast (ed. A Hopkins and D Younie), pp. 160–162. Occasional Symposium No. 27. British Grassland Society, Harrogate, UK.
Reynolds, CK, Huntington, GB, Elsasser, TH, Tyrell, HF, Reynolds, PJ 1989. Net metabolism of hormones by portal drained viscera and liver of lactating Holstein cows. Journal of Dairy Science 72, 14591468.
Robinson, PH, Tamminga, S, van Vuuren, AM 1987. Influence of declining level of feed intake and varying the proportion of starch in the concentrate on milk production and whole tract digestibility in dairy cows. Livestock Production Science 17, 1935.
Steen, RJW 1992. The effects of plane of nutrition and forage to concentrate ratio on the performance and carcase composition of steers. Animal Production 58, 442.
Steen, RJW, Robson, AE 1995. Effects of forage to concentrate ratio in the diet and protein intake on the performance and carcase composition of beef heifers. Journal of Agricultural Science 125, 125135.
Sutton, JD 1985. The digestion and absorption of energy substrates in the lactating dairy cow. Journal of Dairy Science 68, 33763393.
Sutton, JD, Cammell, SB, Phipps, RH, Beever, DE, Humphries, DJ 2000. The effect of crop maturity on the nutritional value of maize silage for lactating cows: 2. Ruminal and post-ruminal digestion. Animal Science 71, 391400.
Theurer, CB 1986. Grain processing effects on starch utilization by ruminants. Journal of Animal Science 63, 16491662.
Thorp, CL, Wylie, ARG, Steen, RJW, Shaw, C, McEvoy, JD 2000. Effects of incremental increases in forage: concentrate ratio on plasma hormone and metabolite concentrations and products of rumen fermentation in fattening beef steers. Animal Science 71, 93109.



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