Net energy value of timothy and bromegrass silages for beef cattle

1998 ◽  
Vol 78 (1) ◽  
pp. 107-114 ◽  
Author(s):  
D. R. Ouellet ◽  
J. R. Seoane ◽  
H. Lapierre ◽  
P. Flipot ◽  
J. F. Bernier

Metabolizable energy (ME), net energy for maintenance and net energy for growth of grass silages were evaluated by the comparative slaughter technique using a 2 × 2 × 3 factorial design. Sixty medium frame beef steers (259 ± 29 kg BW) were divided in groups of five and fed during 3 months either Timothy (T) or Bromegrass (B) harvested at stem elongation (S) of the first cut or at boot stage of the aftermath (A). Forages were fed at one of three levels of intake: ad libitum (FF), 80% of FF, or 65% of FF. Silages averaged 26.9% DM, 16.0% CP and 37.7% ADF. Regression of logarithm of heat production (HE) against ME intake were similar for all silages (log HE = 0.00046*ME + 2.4923; r2 = 0.89). From this equation, fasting HE of 311 kJ kg−0.75 d−1, ME for maintenance of 559 kJ kg−0.75 d−1 and efficiency of utilization of energy for maintenance of 56% were determined. Regression of ME intake against retained energy (RE) were similar for all silages. Efficiency of ME utilization for growth was 33% using the regression of ME over RE with a ME requirement for maintenance fixed at 559 kJ kg−0.75 d−1. Net energy for maintenance and growth were similar for all silages, averaging 6.17 and 3.70 MJ kg−1, respectively. The use of a prediction equation based on ADF of forages underestimated ME values of silages by approximately 25%. Moreover, NRC (1984) equations that estimate NE from experimentally estimated ME values tended to overestimate the net energy of our grass silages. Key words: Net energy, grass silages, timothy, bromegrass, beef cattle

2019 ◽  
Vol 97 (7) ◽  
pp. 3056-3070 ◽  
Author(s):  
Emily A Petzel ◽  
Evan C Titgemeyer ◽  
Alexander J Smart ◽  
Kristin E Hales ◽  
Andrew P Foote ◽  
...  

AbstractTwo experiments were conducted to measure rates of ruminal disappearance, and energy and nutrient availability and N balance among cows fed corn husks, leaves, or stalks. Ruminal disappearance was estimated after incubation of polyester bags containing husks, leaves or stalks in 2 separate ruminally cannulated cows in a completely randomized design. Organic matter (OM) that initially disappeared was greatest for stalks and least for husks and leaves (P < 0.01), but amounts of NDF that initially disappeared was greatest for husks, intermediate for stalks, and least for leaves (P < 0.01). Amounts of DM and OM that slowly disappeared were greatest in husks, intermediate in leaves, and least in stalks (P < 0.01). However, amounts of NDF that slowly disappeared were greatest in leaves, intermediate in husks, and least in stalks (P < 0.01). Rate of DM and OM disappearance was greater for leaves, intermediate for husks and least for stalks, but rate of NDF disappearance was greatest for stalks, intermediate for leaves, and least for husks (P < 0.01). Energy and nutrient availability in husks, leaves, or stalks were measured by feeding ruminally cannulated cows husk-, leaf-, or stalk-based diets in a replicated Latin square. Digestible energy lost as methane was less (P = 0.02) when cows were fed leaves in comparison to husks or stalks, and metabolizable energy (Mcal/kg DM) was greater (P = 0.03) when cows were fed husks and leaves compared with stalks. Heat production (Mcal/d) was not different (P = 0.74) between husks, leaves, or stalks; however, amounts of heat produced as a proportion of digestible energy intake were less (P = 0.05) among cows fed leaves in comparison to stalks or husks. Subsequently, there was a tendency (P = 0.06) for net energy available for maintenance from leaves (1.42 Mcal/kg DM) to be greater than stalks (0.91 Mcal/kg DM), and husks (1.30 Mcal/kg DM) were intermediate. Nitrogen balance was greater when cows were fed leaves, intermediate for husks, and least for stalks (P = 0.01). Total tract digestion of NDF was greater (P < 0.01) for husks and leaves compared with stalks. Husks had greater (P = 0.04) OM digestibility in comparison to stalks, and leaves were intermediate. Apparently, greater production of methane from husks in comparison to leaves limited amounts of energy available for maintenance from husks even though total-tract nutrient digestion was greatest when cows were fed husks or leaves.


1958 ◽  
Vol 195 (3) ◽  
pp. 654-658 ◽  
Author(s):  
F. W. Hill ◽  
L. B. Carew ◽  
A. van Tienhoven

Increased fat production in diethylstilbestrol-treated chicks was found to be due primarily to increased energy consumption and to a lesser extent to preferential synthesis of fat at the expense of protein tissue. This was shown in experiments comparing normal and estrogen-treated male chicks with respect to gains in live weight, fat and protein at two planes of nutrition, and the yield of metabolizable and productive (net) energy which they obtained from the diet. It was found that the fattening effect could not be due to increased digestibility, increased net energy yield from absorbed nutrients, or lowered heat production. Under the influence of estrogen, total tissue gain expressed in Calories was increased, and was composed of greater fat gain and lower protein gain. Tissue energy gains were a linear function of metabolizable energy consumption. This relationship predicted equal tissue energy gains under pair-feeding conditions, which was confirmed experimentally.


Author(s):  
Bonjin Koo ◽  
Olumide Adeshakin ◽  
Charles Martin Nyachoti

Abstract An experiment was performed to evaluate the energy content of extruded-expelled soybean meal (EESBM) and the effects of heat treatment on energy utilization in growing pigs. Eighteen growing barrows (18.03 ± 0.61 kg initial body weight) were individually housed in metabolism crates and randomly allotted to one of three dietary treatments (six replicates/treatment). The three experimental diets were: a corn-soybean meal-based basal diet and two test diets with simple substitution of a basal diet with intact EESBM or heat-treated EESBM (heat-EESBM) at a 7:3 ratio. Intact EESBM was autoclaved at 121°C for 60 min to make heat-treated EESBM. Pigs were fed the experimental diets for 16 d, including 10 d for adaptation and 6 d for total collection of feces and urine. Pigs were then moved into indirect calorimetry chambers to determine 24-h heat production and 12-h fasting heat production. The energy content of EESBM was calculated using the difference method. Data were analyzed using the Mixed procedure of SAS with the individual pig as the experimental unit. Pigs fed heat-EESBM diets showed lower (P &lt; 0.05) apparent total tract digestibility of dry matter (DM), gross energy, and nitrogen than those fed intact EESBM. A trend (P ≤ 0.10) was observed for greater heat increments in pigs fed intact EESBM than those fed heat-EESBM. This resulted in intact EESBM having greater (P &lt; 0.05) digestible energy (DE) and metabolizable energy (ME) contents than heat-EESBM. However, no difference was observed in net energy (NE) contents between intact EESBM and heat-EESBM, showing a tendency (P ≤ 0.10) toward an increase in NE/ME efficiency in heat-EESBM, but comparable NE contents between intact and heat-EESBM. In conclusion, respective values of DE, ME, and NE are 4,591 kcal/kg, 4,099 kcal/kg, and 3,189 kcal/kg in intact EESBM on a DM basis. It is recommended to use NE values of feedstuffs that are exposed to heat for accurate diet formulation.


1979 ◽  
Vol 41 (2) ◽  
pp. 297-310 ◽  
Author(s):  
D. J. Thomson ◽  
S. B. Cammell

1. The efficiency of utilization of the dietary energy and nitrogen contained in a dried lucerne (Medicago sativa cv. Chartainvilliers) given either chopped (CL) or ground (1.96 mm screen) and pelleted (PL), was measured in a comparative slaughter experiment. Growing lambs were given equal amounts of digestible energy in the chopped or pelleted form at each at each of the three planes of nutrition for a period of 100 d.2. The initial energy, fat and protein content of both the carcass and the total body of the test lambs was estimated from regression equations between fasted (18 h) live weight and these components, derived from a group of twenty-three comparable lambs. The final energy, fat and protein content of the test lambs was determined directly by chemical analyses.3. The metabolizable energy (ME) content of the diets was derived at each plane of nutrition from measured faecal and urinary losses and estimated methane losses. The depression in ME content with grinding and pelleting the dried lucerne was small (CL 8.69 MJ/kg dry matter (DM), PL 8.42 MJ/kg DM).4. The efficiency of utilization of the ME of the dried lucerne for growth and fattening was higher (P < 0.01) when given in the ground pelleted form (0.533), than in the chopped form (0.284). The net energy value of the PL (3.5 MJ/kg DM) was higher than that of CL (2.2 MJ/kg DM).5. Thus lambs fed on PL grew faster and had a higher caracass weight gain, carcass protein and fat retention than lambs fed on CL. The composition of the carcass was not altered by the physical processing treatment.6. Digestion studies with these same CL and PL diets had shown that grinding and pelleting depressed digestion in the forestomachs and increased digestion in the small intestine compared with the chopped form. The increased efficiency of utilization of the gross energy and ME and the higher net energy value of PL was attributed primarily to a change in the site of digestion within the alimentary tract. Associated with this change was a higher value for absorbed amino acids : absorbed energy and an increased apparent absorption of methionine for lambs fed on PL. The difference in the energy costs of eating and ruminating the CL and PL was small.


2003 ◽  
Vol 83 (4) ◽  
pp. 787-792
Author(s):  
E. K. Okine ◽  
D. H. McCartney ◽  
J. B. Basarab

The accuracy of predicted CowBytes® versus actual dry matter intake (DMI) and average daily gain (ADG) of 407 Hereford × Angus and Charolais × Maine Anjou (445.6 ± 36 kg) feeder cattle using digestable enery acid detergent fiber (DE) estimated from the (ADF) content [Laboratory analysis method (LAB)] and from values determined in vivo (INVIVO method) was examined. The diet consisted of a 73.3% concentrate diet, 22.0% barley silage, 1.6% molasses, and 3.1% feedlot supplement fed ad libitum (as-fed basis). The calculated DE values of the feed were used to predict the metabolizable energy (ME), net energy of maintenance (NEm), and net energy of gain (NEg) of the diet. These energy values were then used in CowBytes® to predict dry matter intake (DMI), ADG, and days on feed (DOF) necessary to meet targeted quality grade of AA and weights of 522 and 568 kg for the heifers and steers, respectively. There was no effect of gender and prediction method interaction (P > 0.10) on any of the variables measured. There were no (P > 0.05) differences in predicted DMI by either the INVIVO or LAB method but both methods underestimated DMI actually consumed by the cattle by 6.8 and 4.9% (P = 0.007), respectively. Indeed, regression values from these predictive methods and actual DMI were (P < 0.05) different from the one-to-one relationship expected by definition. In spite of the higher actual DMI, the actual ADG of the cattle was 14 and 11% (P = 0.0004) lower than was predicted by either the INVIVO or LAB methods. A possible reason for the lower ADG could be an overestimation of DE of the diet. Thus, if available, users of CowBytes® should use actual DMI from their experience in ration formulation. In addition, the effects of environmental temperature on digestibility of diets should be taken into consideration when using the DE of the diet as determined from in vivo digestibility trials or calculated from chemical analyses in determining the DMI of feedlot cattle. Key words: Beef cattle, performance, CowBytes®, National Research Council


2001 ◽  
Vol 81 (4) ◽  
pp. 553-561 ◽  
Author(s):  
D. R. Ouellet ◽  
J. R. Seoane ◽  
J. F. Bernier ◽  
H. Lapierre

Plasma concentrations of hormones and metabolites were measured in growing steers to establish their relation with degree of feed restriction. Sixty medium frame beef steers (259 ± 29 kg) were divided in groups of five and fed during 3 mo either timothy (T) or bromegrass (B) harvested at stem elongation of the first cut or at boot stage of the aftermath. Forages were fed at one of three levels of intake: ad libitum (FF), 80% of FF, or 65% of FF. Plasma concentrations of growth hormone (GH), insulin, glucagon, insulin-like growth factor-1 (IGF-1), glucose and nonesterfied fatty acids (NEFA) were measured on day 1 and day 78 before the morning meal. The effect of a meal on GH, insulin, glucagon, IGF-1, glucose and NEFA concentrations was also determined in 24 steers sampled from 3 h before to 3 h after a meal. Severity of feed restriction resulted in a linear decrease (P < 0.05) of plasma glucagon (0.139, 0.130, 0.121 ± 0.005 ng mL–1) and IGF-1 (109, 98, 84 ± 7 ng mL–1). Insulin concentration tended to be affected quadratically (0.37, 0.35, 0.27 ± 0.04ng mL–1 for FF, 80% of FF and 65% of FF, respectively, P < 0.10). Ingestion of a meal resulted in a decrease (P < 0.05) of GH, NEFA and glucose, and an increase of insulin concentrations (P < 0.05). There was a positive correlation (r = 0.53, P < 0.05) between IGF-1 and average daily gain, and lipid percentage of carcasses suggesting that IGF-1 is related to growth rate and fat accumulation in growing steers. Key words: Feed restriction, growth hormone, insulin, IGF-I, metabolites, grass silage


1967 ◽  
Vol 18 (1) ◽  
pp. 137 ◽  
Author(s):  
N McCGraham

Energy and nitrogen balance experiments with three subtropical forages, a legume and two grasses, are reported. Each forage was given to four sheep at several levels of feeding. One of the forages had a low nitrogen content (4% crude protein) and was supplemented with urea and molasses containing 7 g nitrogen and 56 kcal/day. This caused voluntary consumption to increase by 50% and digestibility of all chemical constituents to increase by 6–12 units. Utilization of metabolizable energy for maintenance also improved by approximately 10%. Digestible energy (42–62%) was predicted quite accurately from chemical composition by means of published equations which refer to forages grown in temperate climates. Metabolizable energy was close to 82% of digestible energy, as found with non-tropical forages. Net availability of metabolizable energy for maintenance ranged from a very low 60% to 80%. It was predicted more accurately from percentage metabolizable energy than from digestible crude fibre: the reverse applied to net availability for production (40–50%).


2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 166-166
Author(s):  
Bonjin Koo ◽  
Olumide Adeshakin ◽  
Martin Nyachoti

Abstract An experiment was performed to evaluate the energy contents of extruded-expelled soybean meal (EESBM) and the effects of thermal treatment on energy utilization in growing pigs. Eighteen growing barrows (18.03 ± 0.61 kg initial body weight) were individually housed in metabolism crates and randomly allotted to one of three dietary treatments to give six replicates per treatment. The three experimental diets were: a corn-soybean meal-based basal diet and two test diets with simple substitution of a basal diet with intact EESBM or heat-treated EESBM in a 70:30 ratio. Intact EESBM was autoclaved at 120°C for 60 mins to make heat-treated EESBM (heat-EESBM). Pigs were fed the experimental diets for 16 d, including 10 d for adaptation and 6 d for total collection of feces and urine. Pigs were then moved into indirect calorimetry chambers to determine 24-h heat production and 12-h fasting heat production. The energy contents of the tested DESBM were calculated by using the difference method. All data were analyzed using the Mixed procedure of SAS with the individual pig as the experimental unit. Pigs fed heat-EESBM diets showed lower (P &lt; 0.05) apparent total tract digestibility of dry matter (DM), gross energy, and nitrogen than those fed intact EESBM. A trend (P &lt; 0.10) was observed for greater heat increments in pigs fed intact EESBM than those fed heat-EESBM. This resulted in intact EESBM having greater (P &lt; 0.05) digestible energy (DE) and metabolizable energy (ME) contents than heat-EESBM but comparable net energy contents between intact and heat-EESBM. In conclusion, respective values of DE, ME, and net energy are 4,591 kcal/kg, 4,099 kcal/kg, and 3,242 kcal/kg on a DM basis. However, thermal damage during EESBM production should be considered in terms of DE and ME content of EESBM fed to growing pigs.


Author(s):  
T A Woyengo ◽  
R T Zijlstra

Abstract Two experiments were conducted to (1) determine NE values of soybean meal (SBM), Napus canola meal (NCM), Juncea canola meal (JCM), field pea, and wheat millrun (WM) using indirect calorimetry, and (2) compare the determined NE values with the calculated NE values of the same feedstuffs based on a prediction equation. In Experiment 1, 6 ileal-cannulated barrows (31 kg) were fed 5 diets in 5 × 6 Youden square to give 6 replicates per diet. Diets were cornstarch-based diets containing soybean meal (SBM), NCM, JCM, field pea, or WM. The SBM was included as a reference. In Experiment 2, 6 ileal-cannulated barrows (70 kg) were fed a N-free diet for determining energy digestibility and NE values of test feedstuffs fed in Experiment 1 by difference method. The NE values of test feedstuffs were also calculated from the DE values and analyzed macronutrient content of the test feedstuffs (NRC, 2012). On DM basis, SBM, NCM, JCM, field pea, and WM contained 51, 41, 42, 28, and 18% CP; 1.52, 2.95, 2.36, 1.33, and 3.12% ether extract; 2.93, 0.14, 1.44; 36.7, and 28.7% starch; and 5.30, 21.0, 13.4, 9.49, and 16.1% ADF, respectively. The determined NE value for SBM (2.29 Mcal/kg) did not differ from that of NCM (1.72 Mcal/kg DM) or JCM (2.14 Mcal/kg DM). The NCM and JCM did not differ in NE value. Also, the determined NE value did not differ between field pea (2.00 Mcal/kg) and WM (2.55 Mcal/kg). The calculated NE values for SBM (2.18 Mcal/kg DM), NCM (1.73 Mcal/kg DM), and JCM (1.86 Mcal/kg DM) did not differ from the corresponding determined NE values of the same feedstuffs. However, the calculated NE value for field pea (2.51 Mcal/kg DM) was greater (P = 0.004) than the determined NE value of field pea, whereas the calculated NE value for WM (2.27 Mcal/kg DM) tended to be lower (P = 0.054) than the determined NE value of WM. In conclusion, the NE value for SBM and canola meals can be predicted based on the DE value and the macronutrient composition of the same feedstuffs. However, the NE value for field pea and WM may not be predicted precisely based on the DE value and the macronutrient composition of the same feedstuffs.


1973 ◽  
Vol 53 (3) ◽  
pp. 471-477
Author(s):  
D. I. DICKIE ◽  
J. W. WILTON ◽  
T. D. BURGESS

Four studies and populations of beef animals were used to evaluate different methods of expressing energy requirements by comparing actual to predicted gains of bulls and steers fed in Ontario. Large differences between predicted and actual gains occurred. Based on a total of 503 animals, gains predicted by the net energy method (National Academy of Sciences–National Research Council. 1970. Nutrient requirements of domestic animals. 4. Nutrient requirements of beef cattle. (4th rev.). Nat. Acad. Sci., Publ. ISBN 0-309-01754-8; Washington, D.C.) were approximately 20% below the actual gains but exceptions within treatment groups were evident. Three hundred and twenty-five individually fed bulls were used to compare the accuracy with which gains were predicted from equations using total digestible nutrients (National Academy of Sciences–National Research Council. 1963. Nutrient requirements of domestic animals. 4. Nutrient requirements of beef cattle. Nat. Acad. Sci., Publ. 1137, Washington, D.C.) net energy (National Academy of Sciences–National Research Council. 1970. Nutrient requirements of domestic animals. 4. Nutrient requirements of beef cattle. (4th rev.). Nat. Acad. Sci., Publ. ISBN 0-309-01754-8, Washington, D.C), and metabolizable energy (Agricultural Research Council. 1965. The nutrient requirements of farm animals. No. 2. Ruminants. London, England). The metabolizable energy method predicted gains most accurately.


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