|
| |
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Journal of Experimental Biology, Vol 176, Issue 1 31-54, Copyright © 1993 by Company of Biologists
JOURNAL ARTICLES |
K. P. Dial and A. A. Biewener
In vivo measurements of pectoralis muscle force during different modes of free flight (takeoff, level flapping, landing, vertical ascending and near vertical descending flight) were obtained using a strain gauge attached to the dorsal surface of the delto-pectoral crest (DPC) of the humerus in four trained pigeons (Columba livia). In one bird, a rosette strain gauge was attached to the DPC to determine the principal axis of strain produced by tension of the pectoralis. Strain signals recorded during flight were calibrated to force based on in situ measurements of tetanic force and on direct tension applied to the muscle's insertion at the DPC. Rosette strain recordings showed that at maximal force the orientation of tensile principal strain was -15° (proximo-anterior) to the perpendicular axis of the DPC (or +75° to the longitudinal axis of the humerus), ranging from +15 to -25° to the DPC axis during the downstroke. The consistency of tensile principal strain orientation in the DPC confirms the more general use of single-element strain gauges as being a reliable method for determining in vivo pectoralis force generation. Our strain recordings show that the pectoralis begins to develop force as it is being lengthened, during the final one-third of the upstroke, and attains maximum force output while shortening during the first one-third of the downstroke. Force is sustained throughout the entire downstroke, even after the onset of the upstroke for certain flight conditions. Mean peak forces developed by the pectoralis based on measurements from 40 wingbeats for each bird (160 total) were: 24.9+/-3.1 N during takeoff, 19.7+/-2.0 N during level flight (at speeds of about 6-9 m s-1 and a wingbeat frequency of 8.6+/-0.3 Hz), 18.7+/-2.5 N during landing, 23.7+/-2.7 N during near-vertical descent, and 26.0+/-1.8 N during vertical ascending flight. These forces are considerably lower than the maximum isometric force (67 N, P0) of the muscle, ranging from 28 % (landing) to 39 % (vertical ascending) of P0. Based on estimates of muscle fiber length change determined from high- speed (200 frames s-1) light cine films taken of the animals, we calculate the mass-specific power output of the pigeon pectoralis to be 51 W kg-1 during level flight (approximately 8 m s-1), and 119 W kg-1 during takeoff from the ground. When the birds were harnessed with weighted backpacks (50 % and 100 % of body weight), the forces generated by the pectoralis did not significantly exceed those observed in unloaded birds executing vertical ascending flight. These data suggest that the range of force production by the pectoralis under these differing conditions is constrained by the force- velocity properties of the muscle operating at fairly rapid rates of shortening (4.4 fiber lengths s-1 during level flight and 6.7 fiber lengths s-1 during takeoff).
This article has been cited by other articles:
|
|
 |
|
  A. M. Berg and A. A. Biewener Kinematics and power requirements of ascending and descending flight in the pigeon (Columba livia) J. Exp. Biol., April 1, 2008; 211(7): 1120 - 1130. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. W. Tobalske and A. A. Biewener Contractile properties of the pigeon supracoracoideus during different modes of flight J. Exp. Biol., January 15, 2008; 211(2): 170 - 179. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. J. Verspoor, O. P. Love, E. Rowland, E. H. Chin, and T. D. Williams Sex-specific development of avian flight performance under experimentally altered rearing conditions Behav. Ecol., November 1, 2007; 18(6): 967 - 973. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. W. Tobalske Biomechanics of bird flight J. Exp. Biol., September 15, 2007; 210(18): 3135 - 3146. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. L. Hedrick, J. R. Usherwood, and A. A. Biewener Low speed maneuvering flight of the rose-breasted cockatoo (Eolophus roseicapillus). II. Inertial and aerodynamic reorientation J. Exp. Biol., June 1, 2007; 210(11): 1912 - 1924. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. W. Tobalske, L. A. Puccinelli, and D. C. Sheridan Contractile activity of the pectoralis in the zebra finch according to mode and velocity of flap-bounding flight J. Exp. Biol., August 1, 2005; 208(15): 2895 - 2901. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. M. Bishop Circulatory variables and the flight performance of birds J. Exp. Biol., May 1, 2005; 208(9): 1695 - 1708. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Soman, T. L. Hedrick, and A. A. Biewener Regional patterns of pectoralis fascicle strain in the pigeon Columba livia during level flight J. Exp. Biol., February 15, 2005; 208(4): 771 - 786. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R. Usherwood, T. L. Hedrick, C. P. McGowan, and A. A. Biewener Dynamic pressure maps for wings and tails of pigeons in slow, flapping flight, and their energetic implications J. Exp. Biol., January 15, 2005; 208(2): 355 - 369. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R. Lovvorn, Y. Watanuki, A. Kato, Y. Naito, and G. A. Liggins Stroke patterns and regulation of swim speed and energy cost in free-ranging Brunnich's guillemots J. Exp. Biol., December 15, 2004; 207(26): 4679 - 4695. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. S. Tu and T. L. Daniel Cardiac-like behavior of an insect flight muscle J. Exp. Biol., June 15, 2004; 207(14): 2455 - 2464. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. M. Gabaldon, F. E. Nelson, and T. J. Roberts Mechanical function of two ankle extensors in wild turkeys: shifts from energy production to energy absorption during incline versus decline running J. Exp. Biol., June 1, 2004; 207(13): 2277 - 2288. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. A. Biewener, C. McGowan, G. M. Card, and R. V. Baudinette Dynamics of leg muscle function in tammar wallabies (M. eugenii) during level versus incline hopping J. Exp. Biol., January 15, 2004; 207(2): 211 - 223. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R. Usherwood, T. L. Hedrick, and A. A. Biewener The aerodynamics of avian take-off from direct pressure measurements in Canada geese (Branta canadensis) J. Exp. Biol., November 15, 2003; 206(22): 4051 - 4056. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. L. Hedrick, B. W. Tobalske, and A. A. Biewener How cockatiels (Nymphicus hollandicus) modulate pectoralis power output across flight speeds J. Exp. Biol., April 15, 2003; 206(8): 1363 - 1378. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. L. Nudds and D. M. Bryant Consequences of load carrying by birds during short flights are found to be behavioral and not energetic Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2002; 283(1): R249 - R256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. J. Roberts and J. A. Scales Mechanical power output during running accelerations in wild turkeys J. Exp. Biol., May 15, 2002; 205(10): 1485 - 1494. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. N. Askew and R. L. Marsh The mechanical power output of the pectoralis muscle of blue-breasted quail (Coturnix chinensis): the in vivo length cycle and its implications for muscle performance J. Exp. Biol., January 11, 2001; 204(21): 3587 - 3600. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. N. Askew, R. L. Marsh, and C. P. Ellington The mechanical power output of the flight muscles of blue-breasted quail (Coturnix chinensis) during take-off J. Exp. Biol., January 11, 2001; 204(21): 3601 - 3619. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Williamson, K. Dial, and A. Biewener Pectoralis muscle performance during ascending and slow level flight in mallards (Anas platyrhynchos) J. Exp. Biol., January 2, 2001; 204(3): 495 - 507. [Abstract] [PDF]
|
|
|
|
 |
|
 M. H. Dickinson, C. T. Farley, R. J. Full, M. A. Koehl, R. Kram, and S. Lehman How Animals Move: An Integrative View Science, April 7, 2000; 288(5463): 100 - 106. [Abstract] [Full Text]
|
|
|
|
|
|
B. Tobalske and K. Dial Effects of body size on take-off flight performance in the Phasianidae (Aves) J. Exp. Biol., January 11, 2000; 203(21): 3319 - 3332. [Abstract] [PDF]
|
|
|
|
|
|
C. Pennycuick, A Hedenstrom, and M Rosen Horizontal flight of a swallow (Hirundo rustica) observed in a wind tunnel, with a new method for directly measuring mechanical power J. Exp. Biol., January 6, 2000; 203(11): 1755 - 1765. [Abstract] [PDF]
|
|
|
|
|
|
K. Earls Kinematics and mechanics of ground take-off in the starling Sturnis vulgaris and the quail Coturnix coturnix J. Exp. Biol., January 2, 2000; 203(4): 725 - 739. [Abstract] [PDF]
|
|
