論文

査読有り
2008年4月

Effect of culling age of does on milk and meat production in Japanese-Saanen goats

LIVESTOCK SCIENCE
  • K. Oishi
  • ,
  • A. K. Kahi
  • ,
  • Y. Nagura
  • ,
  • M. Fujita
  • ,
  • H. Hirooka

114
2-3
開始ページ
220
終了ページ
232
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1016/j.livsci.2007.05.003
出版者・発行元
ELSEVIER SCIENCE BV

A functional herd dynamics model was developed to estimate the effect of culling age on milk and meat production for Japanese-Saanen goats in relation to changes in prices of milk and meat. The model simulates life cycle production of bucks and does and their kids. Every production trait is first modelled as an individual trait and thereafter as a trait in the herd using a herd dynamics model. At the individual level, the survival curve function, the litter size function and the production traits function are combined. Data on growth and lactation were used to fit growth and lactation curves to estimated parameters using non-linear least squares regression technique and used in the production traits function. Using herd dynamics, the individual level functions are combined with the total number of animals function to estimate the total herd output and income efficiency at the herd level. Here, variables of culling days including the effect of difference in meat price value among goat categories (bucks, does, male kids and female kids) are used. Analysis of interrelations among the culling days of does, the price ratio and the income efficiency indicated that optimal culling days of does was shortened with an increase in the price ratio of meat to milk. However, when meat price value was different among goat categories according to actual situation of Japanese goat production, the optimal culling days of does could be fixed regardless of the change in price ratio and was calculated as 1730 days. This functional herd dynamics model can aid in decision-making regarding culling under several situations especially when there is a wide fluctuation in prices at local markets. (C) 2007 Elsevier B.V. All rights reserved.

リンク情報
DOI
https://doi.org/10.1016/j.livsci.2007.05.003
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000255514500010&DestApp=WOS_CPL
ID情報
  • DOI : 10.1016/j.livsci.2007.05.003
  • ISSN : 1871-1413
  • Web of Science ID : WOS:000255514500010

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