Muscle activity and hydrodynamic function of pelvic fins in trout (Oncorhynchus mykiss).

نویسنده

  • E M Standen
چکیده

Contrary to the previous premise that pelvic fins lacked obvious function, recent work on three-dimensional fin motions suggests that pelvic fins actively control stability and speed in slowly swimming trout. This study used electromyography to measure pelvic fin muscle activity and particle imaging velocimetry to quantify flow along the ventral body region to test this hypothesis. Fish swam at slow speeds (0.13-1.36 BL s(-1)) while being filmed with three high speed cameras. Three-dimensional kinematics were captured for all trials. During EMG trials pelvic fin muscle activity was synchronized to kinematic motion, during particle imaging velocimetry trials, a laser light-sheet was used to visualize the flow surrounding the ventral aspect of the fish. Four main conclusions are reached: first, pelvic fins are actively oscillated during slow-speed swimming; antagonistic abductor and adductor muscles contracted simultaneously, their collective action producing a unique contralateral oscillating behaviour in the fins. Second, pelvic fins slow the flow along the ventral side affecting pitch and yaw instabilities; flow upstream of the pelvic fins is slowed by 0.02 m s(-1) and flow downstream of the pelvic fins is slowed by 0.034 m s(-1) compared with free stream flow. Third, pelvic fin wake influences anal fin angle of attack; flow angle in the wake of the pelvic fin was 33.84+/-2.4 deg. (max) and -11.83+/-11.2 deg. (min) compared with the free stream flow angle of 1.27+/-0.1 deg. Fourth, pelvic fins appear to actively damp body oscillation during slow-speed swimming, providing drag to help control speed and stabilize the body position during slow-speed swimming.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Pelvic fin locomotor function in fishes: three-dimensional kinematics in rainbow trout (Oncorhynchus mykiss).

The paired pelvic fins in fishes have been the subject of few studies. Early work that amputated pelvic fins concluded that these fins had very limited, and mainly passive, stabilizing function during locomotion. This paper is the first to use three-dimensional kinematic analysis of paired pelvic fins to formulate hypotheses of pelvic fin function. Rainbow trout (Oncorhynchus mykiss) were filme...

متن کامل

Neuromuscular control of trout swimming in a vortex street: implications for energy economy during the Karman gait.

Approximating the complexity of natural locomotor conditions provides insight into the diversity of mechanisms that enable animals to successfully navigate through their environment. When exposed to vortices shed from a cylinder, fishes hold station by adopting a mode of locomotion called the Kármán gait, whereby the body of the fish displays large, lateral oscillations and the tail-beat freque...

متن کامل

Myotomal slow muscle function of rainbow trout Oncorhynchus mykiss during steady swimming.

Strain and activity patterns were determined during slow steady swimming (tailbeat frequency 1.5-2.5 Hz) at three locations on the body in the slow myotomal muscle of rainbow trout Oncorhynchus mykiss using sonomicrometry and electromyography. Strain was independent of tailbeat frequency over the range studied and increased significantly from +/-3.3 % l0 at 0.35BL to +/-6 % at 0.65BL, where l0 ...

متن کامل

Wake dynamics and locomotor function in fishes: interpreting evolutionary patterns in pectoral fin design.

The great anatomical diversification of paired fins within the Actinopterygii (ray-finned fishes) can be understood as a suite of evolutionary transformations in design. At a broad taxonomic scale, two clear trends exist in the morphology of the anteriorly situated pectoral fins. In comparing basal to more derived clades, there are general patterns of (i) reorientation of the pectoral fin base ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • The Journal of experimental biology

دوره 213 5  شماره 

صفحات  -

تاریخ انتشار 2010