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					                                       Effects of Blindfolding on Behaviour and
                                      Heart Rate in Beef Cattle During Restraint
                                                            K.D. Mitchell, J.M. Stookey , D.K. Laturnas, J.M. Watts,                                                                                         Large Animal Clinical Sciences
University of Saskatchewan                                                  D.B. Haley and T. Hudye                                                                                                      Western College of Veterinary Medicine

 INTRODUCTION                                                                                                      MATERIALS and METHODS (continued)

      Restriction of an animal’s visual field by means of a blindfold or hood has                                        Exertion Force measurements: Strain gauges were attached to the head
 been suggested for use during the handling and restraint of many wild and captive                                 gate to measure the animal’s struggle. Signals from strain gauges (Fig. 5) were
 animals (Fig. 1) (Fowler, 1995).                                                                                  digitized and used to determine the average and maximum exertion forces made
                                                                                                                   by the heifers during restraint.



                                                                                                                                                                                           Sample tracing
                                                                                                                                                                           2                                             Max. force




                                                                                                                                                     Stimulus strength
                                                                                                                                                                         1.5




                                                                                                                                                          (volts)
                                                                                                                                                                           1
                                                                                                                                                                         0.5
                                                                                                                                                                           0
                                                                                                                                                                         -0.5 0                   10                               20                   30
    Fig.1 Examples of blindfolds and hoods used during handling and restraint in raptors,
                                                                                                                                                                                                       Time (seconds)
    domestic elk and a cat.

       The practice of using blindfolds on cattle is not uncommon (Ewbanks, 2000)                                                                Fig.5 Example of strain gauge signal from heifer
 (Fig. 2) and the use of a black box has been reported to have a calming effect on                                                               showing the maximum exertion force against
 cattle (Grandin, 2000), but no data has ever been presented to verify that cattle are                                                           head gate occurring at roughly 12 sec during the
 indeed calmer during a procedure if a blindfold is used.                                                                                        restraint.


                                                                                                 Statistical analysis: The association between treatment, sample time (day 0 to
                                                                                            4), animal weight and the various outcome measures were analyzed using a
  QUESTION
                                                                                            generalized estimating equations (GEE) method to account for the repeated
                                                                                            measures design. Variables remaining in the final multivariate model at P<0.05,
  Does blindfolding cattle during restraint
                                                                                            based on the robust empirical standard errors produced by GEE analysis, were
  have a calming effect?
                                                                                            considered statistically significant.

            Fig. 2 An example of a blindfold
            being used on a bovine during a
                                                                                            RESULTS
            surgical procedure
                                                                                                                                   Mean heartrate after experimental protocol.                                                       Average difference between pre and post heart rates.
                                                                                                                                                                                                                                   30
                                                                                                                       160                                                                                                                                                                  Control
                                                                                                                                                                                           Control                                 25
                                                                                             Heart rate (cycles/min)




                                                                                                                       140                                                                                                                                                                  Blindfold




                                                                                                                                                                                                               (cycles / min)
                                                                                                                                                                                           Blindfold




                                                                                                                                                                                                                 Difference
                                                                                                                       120                                                                                                         20
                                                                                                                       100
                                                                                                                                                                                                                                   15
                                                                                                                        80

  MATERIALS and METHODS                                                                                                 60
                                                                                                                                                                                                                                   10

                                                                                                                        40                                                                                                          5


       60 beef heifers were randomly assigned to visual restriction (Blindfold) (n=30)
                                                                                                                        20                                                                                                          0
                                                                                                                         0                                                                                                                   1               2             3           4

  or no visual restriction (Control) (n=30) during a 4 day trial to determine the effects
                                                                                                                                   1             2                         3       4
                                                                                                                                                                                                                                                                 Day
                                                                                                                                                         Days

  during restraint (Fig. 3a and 3b). Measurements were taken each day during a
                                                                                            Fig. 6a. Mean heart rate of blindfolded                                                                           Fig. 6b. The average decrease in heart
  baseline period and a 1 minute period of restraint with handling/touching the
                                                                                            and control heifers during 1 minute                                                                               rate for blindfolded and control heifers
  animal.    Touching involved 2 people on opposite sides of the animal,
  simultaneously approaching the animal at 15 sec into the restraint period and             period of restraint (P=.64).                                                                                      during 1 min period of restraint (P = .10).
  grabbing the ear, poking the neck, side and rump in a mock “ear tagging,
  vaccinating and prodding” procedure.
                                                                                                                                       Mean force values during treatment.                                                               Maximum force values during treatment.
                                                                                                                             0.7
                                                                                                                                                                                            Control                                3.5
                                                                                                Stimulus strength




                                                                                                                             0.6
                                                                                                                                                                                                               Stimulus strength




                                                                                                                                                                                                                                    3                                                      Control
                                                                                                                                                                                            Blindfold
                                                                                                                             0.5                                                                                                                                                           Blindfold
                                                                                                                                                                                                                                   2.5
                                                                                                     (volts)




                                                                                                                                                                                                                    (volts)




                                                                                                                             0.4                                                                                                    2
                                                                                                                             0.3                                                                                                   1.5
                                                                                                                             0.2                                                                                                    1

                                                                                                                             0.1                                                                                                   0.5
                                                                                                                                                                                                                                    0
                                                                                                                              0
                                                                                                                                                                                                                                            1            2             3           4
                                                                                                                                       1             2                         3       4
                                                                                                                                                                   Day                                                                                           Day


                                                                                            Fig. 7a. Mean exertion force applied                                                                              Fig. 7b. Maximum force exerted against
                                                                                            against the head gate by blindfolded and                                                                          the head gate by blindfolded and control
                                                                                            control heifers during 1 min period of                                                                            heifers during 1 minute period of
                                                                                            restraint (P<.05).                                                                                                restraint (P<.01).

             Fig. 3a. Blindfolded heifer                    Fig. 3b Control heifer
                                                                                            CONCLUSIONS
             during restraint.                              during restraint.
                       Blindfold or   Touching   Touching       End                         1)                                We have demonstrated that there is a positive behavioural and physiological
                         Control        starts     ends
                                                                                                                              response to blindfolding beef cattle during restraint.
                                                                                            2)                                Heart rate tends to decrease during restraint for blindfolded animals. A
                                                                                                                              larger sample size may reveal stronger evidence for this response.
                                 15 sec     15 sec     15 sec
                                                                                            3)                                Blindfolded animals struggle less against the head gate during restraint
                                                                                                                              compared to controls.
                                Pre-Touch    Touch Post-Touch
                                                                                            4)                                We recommend cattle be blindfolded for invasive procedures that require
                                                                                                                              prolonged restraint.
                              Pre Heart                      Post Heart
                                Rate                           Rate                                    ACKNOWLEDGEMENTS
                                                                                                           Funding for this research was provided by the Interprovincial Summer Student
   Fig. 4. Heart rate was measured via telemetry system during times indicated above.                  Research Project Fund and the Saskatchewan Agricultural Development Strategic Fund.

				
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