Data/hora: 07/06/2024 02:24:21

Biblioteca(s): | Embrapa Pantanal.
Data corrente: | 30/03/1999
Data da última atualização: | 30/03/1999
Autoria: | MILLS, C. F.; DALGARNO, A. C.; WILLIAMS, R. B.; QUARTEMAN, J.
Afiliação: | Rowett Research Institute, Bucksburn, Aberdeen.
Título: | Zinc deficiency and the zinc requirements of calves and lambs.
Ano de publicação: | 1967
Fonte/Imprenta: | British Journal of Nutrition, v.21, p.751-768, 1967.
Idioma: | Inglês

Conteúdo:

1. The effects of changes in zinc intake on weight gain, plasma Zn concentration and the develeopment of clinical lesions of zn deficiency ahave been studied in zn depletion and repletion studies with calves and lambs.
2. A basal diet, the principal components of which are urea, dried egg white, starch, glucose, cellulose and arachis oil has been developed for trace element deficiency studies with ruminants.
3. weight gain ceased abruptly in both calves and lambs when either the unsupplemented basal diet was given or when zn supplements provided only 0.05 mg Zn/kg live weight per day. Mean plasma Zn concentrations in these animals fell from pre-experiment values of between 0.8 and 1.2 ug Zn/ml to below 0.4 ug Zn/ml I week on these treatments.
4. Supplements providing 0.2 mg Zn/kg live weight per day were sufficient to maintain a good rate of growth but insufficient to prtevent a fall in plasma zn.
5. Growth arrest occurring within 2 weeks and a rapoid fall in plasma zn occurring within I week after zn supplements were withheld from calves and lambs that had previously receiuved 0.7 mg Zn/kg live weight per day for 6 and 14 weeks respectively indicated that these species have only a liomited capacity to store Zn in a form that can be utilized during periods of inadequate Zn intake. 
6. tentative estimates are presented of the Zn requirements of calves maintained on this type of basal diet and the influence of rationa compositiona on zn availability is discused.
7. The possible value and the limitations of plasma Zn determination as an aid to the field diagnosis of Zn deficiency are considered.

Palavras-Chave: | Dediciencia de zinco; Lambs: Zinc deficiency.
Thesagro: | Bezerro; Cordeiro.
Thesaurus Nal: | calves.
Categoria do assunto: | --
Registro original: | Embrapa Pantanal (CPAP)
Exemplares: | CPAP - (37861-1) - ADD - SP - -- - SP4419 -  - 4419 - DIS