Body condition of a small passerine bird: ultrasonic assessment and significance in overwinter survival

Abstract

The fitness benefits of intraspecific variation in physiological attributes have rarely been measured. Body condition, defined as the current status of metabolic reserves relative to likely demands, has often been implicated in subsequent survival, but has proved difficult to assess reliably in the live animal. A technique for assessing body condition, in terms of the main protein reserve of small birds, is presented. Pectoralis muscle thickness was measured in live birds using ultrasound reflection from the sternum. The relationship between the relative size of pectoralis muscles in autumn and the likelihood of overwinter survival in the dipper Cinclus cinclus was examined. The pectoralis reserves of male dippers surviving overwinter were significantly greater than those of birds which died or disappeared between late November and the breeding season in April. In contrast, variation in autumn condition of females was unrelated to overwinter survival.

Estimating Organ Size in Small Migrating Shorebirds with Ultrasonography: An Intercalibration Exercise

“…Correlation coefficients of the relationship between ultrasound measure and organ mass in knots (0.792-0.928) are comparable with those found for swans (Cygnus olor, 0.929;Sears 1988), dippers (Cinclus cinclus, 0.859;Newton 1993), and canaries (Serinus canaria, 0.927;Newton 1993) and also with the range of the correlation coefficients between the ultrasound measure and fat thickness or muscle area in beef cattle (Perkins et al 1992;Herring et al 1994). Values obtained in plovers were substantially lower (0.118-0.820), however.…”

“…Initially, the ultrasound technique involved the "pulse-echo" method, in which the time passed between the input signal and the reflected output signal gives an indication of the thickness of the medium scanned (e.g., Sears 1988;Newton 1993). Today, ultrasound technique also involves ultrasonographic imaging, which has the major advantage that the "landscape" of the internal organs and skeleton is visible.…”

“…Some noninvasive methods currently are available to monitor organ size in live animals: x-ray techniques (Fuller et al 1994;Duke et al 1997), nuclear magnetic resonance (Fuller et al 1994;Wasser et al 1996), and ultrasonographic scanning (Newton 1993;Fuller et al 1994;Herring et al 1994). Each method has certain advantages and disadvantages (Fuller et al 1994), and most techniques are not suitable for estimating the size or mass of particular organs.…”

“…Ultrasonographic measurements distress animals relatively little and are commonly used in humans and animals for diagnostic purposes (e.g., Grooters et al 1994;Lambertz et al 1995) and in the context of animal production (e.g., Perkins et al 1992;Herring et al 1994;Chiba 1995). Ultrasonography has been used in a few ecophysiological studies (e.g., Sears 1988;Newton 1993;Reimers et al 1993;Woodroffe 1995;Haefner et al 1996).…”

Use of portable ultrasonography as a nondestructive method for estimating reproductive effort in lizards

“…Studies published using ultrasound imaging have included such diverse taxa as chicken (Melnychuk et al, 2001), birds (Newton, 1993;Sears, 1998;Dietz et al, 1999;Dekinga et al, 2001), cattle (Chupin and Procureur, 1983;Perkins et al, 1992;Herring et al, 1994;Pierson and Ginther, 1998), pigs (Chiba, 1995), molluscs (Haefner et al, 1996), fish (Reimers et al, 1993;Evans et al, 2004) and badgers (Woodroffe, 1995) [see also Hildebrandt et al (Hildebrandt et al, 1998) and Starck et al (Starck et al, 2001) for review and technical information].…”