Estimating carcass fat and protein in northern pintails during the nonbreeding season

Michael R. Miller

doi:10.2307/3801318

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Estimating carcass fat and protein in northern pintails during the nonbreeding season

Michael R. Miller

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Abstract

I used northern pintails ( Anas acuta ) collected from August through March 1979-82 in the Sacramento Valley, California to derive equations to predict ether-extracted carcass fat, carcass protein, and skeletal lean dry weight. Ether-extracted carcass fat was best predicted by total fat depot weight (wet skin, abdominal fat, and intestinal fat) (r 2 = 0.94) and estimates based on carcass water content (r 2 = 0.93-0.98). Measured carcass protein was best predicted by a multiple regression including total protein depot weight (breast muscles, leg muscles, and gizzard) and tarsus length (R 2 = 0.79). I predicted skeletal lean dry weight by a multiple regression incorporating culmen, tarsus, and wing length (R 2 = 0.77). Predicted carcass fat agreed well with measured carcass fat in an independent data set of 30 pintails using total fat depot (r 2 = 0.92-0.96) and carcass water (r 2 = 0.97-0.99), but predicted carcass protein agreed less well with measured protein.

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Journal of Wildlife Management Article

Source-reported bounding extent: 38.453726657480416° to 39.368415331346114° latitude; -121.92010720240859° to -120.9862693117838° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Michael R. Miller. 1989. Estimating carcass fat and protein in northern pintails during the nonbreeding season. https://doi.org/10.2307/3801318

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