AN EVALUATION OF TOTAL DIGESTIBLE NUTRIENTS, METABOLIZABLE ENERGY, AND NET ENERGY FOR THE PREDICTION OF ENERGY REQUIREMENTS FOR BEEF CATTLE IN ONTARIO

1973 ◽  
Vol 53 (3) ◽  
pp. 471-477
Author(s):  
D. I. DICKIE ◽  
J. W. WILTON ◽  
T. D. BURGESS
Keyword(s):  
Beef Cattle ◽  
Research Council ◽  
National Research Council ◽  
Domestic Animals ◽  
Metabolizable Energy ◽  
Energy Requirements ◽  
Net Energy ◽  
Nutrient Requirements ◽  
National Academy Of Sciences ◽  
Academy Of Sciences

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.

Energy and protein utilization for maintenance and growth in Omani ram lambs in hot climates. I. Estimates of energy requirements and efficiency

2001 ◽  
Vol 136 (4) ◽  
pp. 451-459 ◽  
Author(s):  
R. J. EARLY ◽  
O. MAHGOUB ◽  
C. D. LU
Keyword(s):  
Research Council ◽  
Geometric Mean ◽  
National Research Council ◽  
Live Weight ◽  
Metabolizable Energy ◽  
Energy Requirements ◽  
Maximum Temperature ◽  
Net Energy ◽  
Linear Quadratic ◽  
Temperate Climates

Energy requirements for maintenance and growth were estimated by comparative slaughter in Omani male lambs during the hot summer months (July–October: maximum temperature, 48 °C). Weaned lambs (n = 10 per diet) were fed one of three totally mixed, 160 g CP/kg DM diets that contained 600, 400 or 200 g rhodesgrass hay/kg for low (9·98 MJ/kg, medium (10·3 MJ/kg) and high (11·4 MJ/kg) energy contents, respectively. All diets were balanced to meet the minimum nutritional needs for maximum growth. The trial lasted for 113–114 days. The purpose of having three diets was to induce a broad spectrum of growth rates that could be used in regression analysis (tested for linear, quadratic and exponential effects). Metabolizable energy (ME) intake was regressed on live weight (LW), empty body weight, tissue energy and tissue protein gain and vice versa. Coefficients of determinations were not significantly improved by quadratic or logarithmic regressions over linear relationships. Geometric mean regressions were used to control further biases due to major axis dependence when Y is regressed on X or vice versa. Based on tissue energy gain, the best estimates of ME required for maintenance (MEm) and gain (MEg) were 526 kJ/kg LW0·75/d and 42·1 kJ/kg LW0·75/g LW gain, respectively. Net energy values for maintenance (NEm) and gain (NEg) were 278 kJ/kg LW0·75/d and 20·6 kJ/kg LW0·75/g LW gain, respectively. These equations predicted MEm and NEm requirements that were similar to or slightly greater than those established by the US National Research Council (1985) and the UK Agricultural and Food Research Council (1993) for growing male lambs. The MEg and NEg requirements were substantially greater (by 43–89%) in this respect. Efficiency values were calculated as net energy available for maintenance or gain divided by the metabolizable energy available for maintenance or gain. The efficiency of metabolizable energy used for maintenance and gain was 0·50 and 0·52, respectively, and did not appear to be much different from values for other breeds of sheep in temperate climates. Dietary energy concentrations did not affect the efficiency of energy deposition. The data suggest that Omani sheep in hot climates have greater NEg requirements, and consequently MEg requirements, than other breeds of sheep in temperate climates.

Evaluation of the National Research Council (NRC) nutrient requirements for beef cattle: Predicting feedlot performance

2003 ◽  
Vol 83 (4) ◽  
pp. 787-792
Author(s):  
E. K. Okine ◽  
D. H. McCartney ◽  
J. B. Basarab
Keyword(s):  
Beef Cattle ◽  
Dry Matter ◽  
Research Council ◽  
Average Daily Gain ◽  
National Research Council ◽  
Metabolizable Energy ◽  
Dry Matter Intake ◽  
Net Energy ◽  
Feeder Cattle

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

The National Research Council Committee on Human Factors

1989 ◽  
Vol 33 (10) ◽  
pp. 568-570
Author(s):  
Harold P. Van Cott
Keyword(s):  
Human Factors ◽  
Research Council ◽  
National Research Council ◽  
National Academy Of Sciences ◽  
Standing Committee ◽  
Technical Systems ◽  
Academy Of Sciences ◽  
National Research Council Committee

The Committee on Human Factors, a standing committee of the National Academy of Sciences/National Research Council (NAS/NRC), advises its sustaining sponsors and other requesting organizations on issues involved in the design of socio-technical systems and on the research and methods needed to help enhance their operability and safety. This paper describes the origins, purposes, operations and program of the committee and emphasizes the special attributes of this and other NAS/NRC commtittees.

The me system : The biological basis

1986 ◽  
Vol 1986 ◽  
pp. 60-60
Author(s):  
D.J. Thomson ◽  
M.J. Haines ◽  
S.B. Cammell ◽  
M.S. Dhanoa
Keyword(s):  
Research Council ◽  
Agricultural Research ◽  
Metabolizable Energy ◽  
Energy Requirements ◽  
Nutrient Requirements ◽  
Animal Performance ◽  
Biological Basis ◽  
Additional Information ◽  
Agricultural Research Council ◽  
New System

The Starch Equivalent (SE) system devised by Kellner for expressing the energy requirements of ruminants and the energy value of feeds was used in Britain from 1912. Metabolizable energy (ME) was proposed (Agricultural Research Council, 1965) and adopted (MAFF, DAFS and DANI, Technical Bulletin 33, 197S), as a basis for a new system relating diet to the energy requirements of animals. Additional information was incorporated in the extensive Technical Review (The Nutrient Requirements of Ruminant Livestock, 1980). Metabolizable energy was retained, and animal performance it was claimed, was predicted more precisely with ME than SE. Results presented in this paper are for the comparison, and interpretation, of observed and predicted (Technical Bulletin 33) rates of gain, and other components of the ME system, for growing lambs and cattle fed forage and mixed forage and concentrate diets.

Monitoring of Coastal Ocean Waters Receiving Wastewaters in the USA: Review of Two 1990 Publications of the USA National Research Council – National Academy of Sciences and National Academy of Engineering

1992 ◽  
Vol 25 (9) ◽  
pp. 49-57
Author(s):  
W. F. Garber
Keyword(s):  
Coastal Waters ◽  
Research Council ◽  
National Research Council ◽  
National Academy Of Sciences ◽  
Water Contact ◽  
National Monitoring ◽  
Usable Information ◽  
The Usa ◽  
Monitoring Effort ◽  
Academy Of Sciences

Required monitoring of the physical, biological and chemical condition of the nearshore waters of the ocean receiving treated wastewaters has been underway in the U.S.A. since 1955 or about 35 years. When established the stated intent had been to utilize the information obtained to evaluate the effects of the diffusion of wastewaters upon the beneficial values of these receiving waters. That is upon the food web including game and food fish; upon water contact sports uses; upon aesthetics; and upon the local, regional, and worldwide ecology. To this end original requirements had included a provision that the regulatory agency reduce the data obtained from the monitoring effort to information useful to themselves as well as to facility design and operational authorities. Inasmuch as the monitoring effort in 1989 was using funds in excess of 130 million dollars per year and had a 35 year data base, the Marine Board of the National Research Council - National Academy of Sciences: National Academy of Engineering established committees of scientists to evaluate the progress of the national monitoring effort and of the longest and most complete program of the Southern California Bight. It was found that the essential portion of the program, that of reducing the data obtained to usable information, had not been carried on so that approximately 35 years of data existed with little to zero information. In addition the data existed in pools of intensive samplings around discharge points with very little overall study of the coastal waters. Whether the discharge points were significantly different from the “normal” coastal waters was not really known because “normal” was not known. The Committees recommended procedures to follow to rectify these basic problems including reallocation of current funding to cover the research, control, design and operational needs. Their findings are summarized in the paper.

Sign in / Sign up

Export Citation Format

Share Document