Utilização de indicadores para estimar a digestibilidade aparente em gatos

Abstract

RESUMOCompararam-se os métodos de coleta total (CT) e dos indicadores óxido crômico (Cr2O3), cinzas insolúveis em ácido (CIA) e lignina na determinação dos coeficientes de digestibilidade aparente (CDA) dos nutrientes para gatos. Os CDA de quatro rações foram determinados pela CT e estimados pelos diferentes indicadores em teste. Foram utilizados 24 gatos adultos castrados, alojados em gaiolas metabólicas individuais, totalizando seis animais por ração. O experimento seguiu um delineamento inteiramente ao acaso, em parcelas subdivididas, sendo as rações as parcelas, os métodos as subparcelas e cada gato uma unidade experimental. Os CDA foram significativamente menores pelo método da lignina em uma das rações estudadas (P<0,05). Os métodos Cr2O3, CIA e CT resultaram em CDA iguais em todas as rações (P>0,05). As taxas de recuperação dos indicadores, médias±erro-padrão da média, foram, respectivamente, de 97,1±2,5%, 97,3±2,9% e 83,9±9,1% para o Cr2O3, CIA e lignina. A CIA e o Cr2O3 mostraram grande potencial para utilização como indicadores, enquanto a ampla variabilidade dos resultados obtidos com a utilização da lignina não justificou seu emprego como substância índice para felinos.Palavras-chave: gato, óxido crômico, lignina, cinzas insolúveis em ácido, digestibilidade aparente ABSTRACT The total collection (TC) method was compared to chromium oxide (Cr 2 O 3 ), acid-insoluble ash (AIA) and lignin marker methods for determining the coefficients of apparent digestibility (CAD) of nutrients in domestic

Comparison of methods for determination of nutrient digestibility of a dry kibble diet for ocelots

“…CADDM = coefficient of apparent digestibility for dry matter, CADCP = coefficient of apparent digestibility for crude protein, CADEE = coefficient of apparent digestibility for ether extract), CADNFE = coefficient of apparent digestibility for nitrogen-free extracts), CADGE = coefficient of apparent digestibility for gross energy. The concentration of AIA (0.729%) in the dry kibble of this experiment is, according to Thonney et al (1985), subject to larger errors in the laboratorial quantification; however, the CAD results were analogous to those of TFC, validating what had already been reported by Vasconcellos et al (2007), who used diets containing 0.11 or 0.18% of that marker and still obtained adequate determinations of CAD for all nutrients. Despite similarities, the coefficients of digestibility were slightly higher when determined by the AIA method, ranging from 1.31 to 4.25% for CADNFE and CADDM, respectively (Fig.1).…”

“…The CADNFE observed in this study (78.52%) was similar to the findings of Carciofi et al (1998) and Vasconcellos et al (2007), but smaller than the results reported by Lôbo Jr. et al (2001). The 80.5% CADGE was similar to Crissey et al (1998), Lôbo Jr. et al (2001 and Vasconcellos et al (2007) data, but inferior to Vester et al (2010).…”

“…This information confirms Carciofi et al (1998), Lôbo Jr. et al (2001, and Vasconcellos et al (2007), who verified AIA as an efficient method in this determination . Lôbo Jr. et al (2001) reported that ADF underrated the CAD determined by total fecal collection, in contrast to Carciofi et al (1998), who deem CF and ADF efficient in this determination, but suggest the need for new studies to confirm such conclusion.…”

“…The 85% ether extract apparent digestibility was similar to Carciofi et al (1998), Lôbo Jr. et al (2001 and Vasconcellos et al (2007); however, it was inferior to results obtained by Vester et al (2010). The CADNFE observed in this study (78.52%) was similar to the findings of Carciofi et al (1998) and Vasconcellos et al (2007), but smaller than the results reported by Lôbo Jr. et al (2001).…”

“…On the other hand, the methods of partial fecal collection (indirect) do not need metabolic cages; instead, they make use of markers in nourishment, allowing the calculation of the estimated apparent digestibility through a proportion between the ingredient and marker ingested, and the nutrient and marker that were evacuated (Sibbald 1982, Carciofi 1998, Vasconcellos et al 2007. Among the markers used in the evaluation of digestibility of domestic cats, chromic oxide (Cr2O3) is the most employed (Vasconcellos 2007); nevertheless, new methods such as crude fiber (CF), acid-detergent fiber (ADF), and acid-insoluble ash (AIA) have been subject of debate (Carciofi et al 1998, Lôbo Jr. et al 2001, Vasconcellos et al 2007). CF and ADF correspond to the portions of the cell wall over which the digestive enzymes of mammals with undeveloped cecum are almost unable to act, therefore their assimilation relies on bacterial fermentation (Maynard et al 1979, Sunvold et al 1995, what allows their use as possible natural markers of digestibility for domestic cats (Carciofi et al 1998).…”