BREED CROSS DIFFERENCES IN FEED INPUTS FOR LACTATING BEEF COWS

1988 ◽  
Vol 68 (4) ◽  
pp. 1171-1186
Author(s):  
H. T. FREDEEN ◽  
G. M. WEISS ◽  
G. W. RAHNEFELD ◽  
J. E. LAWSON ◽  
J. A. NEWMAN
Keyword(s):  
Research Council ◽  
Subcutaneous Fat ◽  
National Research Council ◽  
Beef Cows ◽  
National Academy Of Sciences ◽  
Lactating Cows ◽  
Weight Losses ◽  
Maintain Body Weight ◽  
Breed Crosses ◽  
Academy Of Sciences

Feed inputs for lactation were measured over a period of approximately 120 d in dry lot confinement, for each of three successive summers, for two herds of mature beef cows. Each herd, one located at Brandon, Manitoba and one at Manyberries, Alberta, included 10 breed crosses. Nine crosses were produced by mating Charolais (C), Simmental (S), and Limousin (L) sires with Angus (A), Hereford (H), and Shorthorn (N) dams. The Hereford × Angus (HA) served as the control. The data for analysis represented a total of 760 cow years. Cow weight at the start of test (approximately 1 June) was used for estimating the basic daily feed requirements. Average subcutaneous fat at the start of test was also considered at Manyberries. Daily feed inputs were adjusted at approximately 28-d intervals with allowances increased (decreased) as required to correct for losses (gains) of weight or fat of the drylot cows relative to contemporary lactating cows on pasture. This procedure resulted in feed inputs that were considerably in excess of the estimated (NRC-NAS) daily allowances for cows of superior milking ability during the first 3–4 mo of lactation. The heaviest breed cross (CH at Manyberries and CN at Brandon) consumed the most feed, while the lightest breed crosses (HA and LA) consumed the least. Estimated digestible energy offered in the final year averaged 20% (Brandon) and 14% (Manyberries) above National Academy of Sciences — National Research Council (1984) requirements, but these feeding levels were not sufficient to maintain body weight during lactation. Particularly large weight losses at both locations (12–29 kg) were recorded by the LN, SH, SA and SN breed crosses, although the feed allowances for these crosses were above the station averages at both locations. Key words: Beef cows, crossbreds, energy requirements, lactation

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.

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.

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