国立研究開発法人 国際農林水産業研究センター | JIRCAS

Mineral Requirement of Dairy Cows Under High Temperature Conditions

Tropical agriculture research series : proceedings of a symposium on tropical agriculture researches
ISSN
03889386
書誌レコードID(総合目録DB)
AA00870529
本文フルテキスト
Heat stress in summer alters mineral needs in ruminants. The requirements of major minerals (Ca, P, Mg, Na and K) and trace elements (Fe, Zn, Cu, Mn, Se, Mo and Co) in dairy cows under high temperature conditions were evaluated based on balance and feeding trials. Mineral requirements for maintenance in dairy cows increased at high temperatures, since mineral excretion during fasting was enhanced above 27°C. Calcium, P, Mg, and Na contents in milk decreased at high temperatures, while the contents of other elements were not affected by heat stress.
Calcium and P balances in lactating cows were negative when milk production was high under optimum temperature conditions. Major mineral and trace element requirements in lactating cows under optimum temperature conditions which were calculated from 24 balance trials at 18°C were almost similar to the estimates of NRC standard, except for the Ca, Mn and Co requirements. Since the intake and apparent absorption of major mineral and trace elements in lactating cows were depressed by heat stress, it is suggested that the mineral requirements in lactating cows increase under high temperature conditions.

刊行年月1991-09-24
作成者Shin-ichi Kume
公開者Japan International Research Center for Agricultural Sciences
25
開始ページ199
終了ページ207
言語eng