Data/hora: 01/06/2024 19:06:56

Provedor de dados: | Revista Brasileira de Zootecnia
País: | Brazil
Título: | Models for estimating feed intake in small ruminants
Autores: | Pulina,Giuseppe; Avondo,Marcella; Molle,Giovanni; Francesconi,Ana Helena Dias; Atzori,Alberto Stanislao; Cannas,Antonello.
Data: | 2013-09-01
Ano: | 2013
Palavras-chave: | Dry matter intake; Feedlot; Goats; Grazing; Modeling; Sheep.
Resumo: | This review deals with the most relevant limits and developments of the modeling of intake of sheep and goats reared intensively and extensively. Because small ruminants are normally fed ad libitum, voluntary feed intake is crucial in feeding tactics and strategies aimed at optimal animal production. The effects of genetic, neuroendocrine, hormonal, feed and environmental factors on voluntary feed intake were discussed. Then, several mathematical models to estimate dry matter intake (DMI) were examined, with emphasis on empirical models for sheep and goats in intensive farm systems or in extensive areas under pasture or rangeland conditions. A sensitivity analysis of four models of prediction of DMI in housed lactating dairy sheep and meat sheep breeds was also presented. This work evidenced a large variability in the approaches used and in the variables considered for housed sheep and goats. Regarding the estimation of feed intake for grazing sheep and browsing goats, the accuracy of estimates based on empirical models developed so far is very low when applied out of the boundaries of the studied system. Feeding experiments indoors and outdoors remain fundamental for a better modeling and understanding of the interactions between feeds and small ruminants. However, there is a need for biological and theoretical frameworks in which these experiments should be carried out, so that appropriate empirical or mechanistic equations to predict DMI could be developed.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013000900010
Editor: | Sociedade Brasileira de Zootecnia
Relação: | 10.1590/S1516-35982013000900010
Formato: | text/html
Fonte: | Revista Brasileira de Zootecnia  v.42 n.9 2013
Fonte: | info:eu-repo/semantics/openAccess