ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1964.tb01152.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Two systems of recording the output of grass fields—by cow‐days (CD.) and by utilized starch equivalent (U.S.E.)—were compared with field measurements of the dry matter and digestible matter consumed over a period of two years.On one farm, each recording system was positively correlated with both the amount of dry matter and the amount of digestible matter consumed from individual fields by grazing cows. Consequently, the two systems reflected equally well the total quantity of utilized herbage and its quality. This was explained by a highly significant correlation between the two recording systems. The same correlation between the two recording systems existed on 20 other farms.It was concluded that the C.D. and the U.S.E. systems gave equally reliable results when assessing field outputwithindairy farms. Because C.D. can be determined with greater ease they should be used instead of the U.S.E. system. However, the U.S.E. system is still advocated for assessing grass utilization for animal production on a farm basis, since it indicates the level of efficiency which farmers achieve in using their

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1964.tb01153.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

A previous paper (2) reported that the utilized‐stareh‐equivalent (U.S.E.) system did not reflect the quantity or quality of herbage consumed better than a much simpler cow‐day (C.D.) system, and. in all the cases studied, the correlation between U.S.E. and CD. was greater than + 0·877.The existing methods of C.D. evaluation are unsatisfactory because methods of equating classes of stock arc widely different and many are arbitrary.An examination has been made of published measurements of herbage intake of groups of sheep and cattle. A regression analysis of cattle intakes gave the equation: dry matter intake (lb) = 0·0234 liveweight + 0·7.The use of this equation is advocated as a basis for assessing the relative herbage intake of cattle and sheep of known liveweights in order to compute the total herbage consumption correcte

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1964.tb01154.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

The traditional method of calculating field output by the utilized‐starch‐equivalent (U.S.E.) system is compared with a recommended simpler and quicker method. The concept of calculating a U.S.E. factor is introduced and forms the basis for the new method. A monthly U.S.E. factor is used, in conjunction with monthly cow‐day (CD.) records to calculate U.S.E. Savings of at least 50% may be expected. Agreement between the two methods is very close and the more seasonal nature of the calculation for sheep and non‐milking cattle under the new method may be pre

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1964.tb01155.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1964.tb01156.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Book reviews in this article:CLARKE, H. G.Commercial sheep management.VOISIN, A.Grass tetany.WALSH, A.Profitable meat production.

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1964.tb01157.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY