miercuri, 10 iunie 2015
Electrocardiographic studies on adult cattle
Electrocardiographic studies on adult cattle
Brăslașu
C.M., Daniela Elena Brăslașu, Simiz Fl., Ghiță M.,
Tudor
Poliana, Cotor G.
Faculty of Veterinary
Medicine, Bucharest
cbraslasu@gmail.com
The cardiac arrhythmias are affections that
can be traced on cardiac and noncardiac diseasses as well. Considering this, it
is important to discover the normal values of the ECG components on this
specie. Thus this paper will try to establish what are these values. Research
was performed on a number of 207 clinically healthy cows (metis breed Holstein;
age ranging between 4 to 8 years old and weight between 400 to 450 kgs).The work parameters were: unipolar and bipolar leads proposed by Dubois
(the first two exploratory electrodes behind the scapulohumeral joint, the
third was placed ventral, behind the xiphoid process, the amplitude, 1 mV=10 mm
and the speed was of 25 mm/sec. The bovines’ electrocardiography shows P and T
waves on the opposite side of the ventricular complex, the values of the ECG
components (II-lead - Average/SD) were: A) the amplitude (mV) of the P wave = 0.177/0.059, the amplitude
of the ventricular complex = 1.181/0.27 and the amplitude of the T wave =
0.453/0.15. B), the duration (sec.) of the P wave = 0.085/0.01, P – R interval = 0.199/0.02, ventricular
complex = 0.081/0.01, Q-T interval = 0.383/0.04, T wave = 0.095/0.02, R-R
interval = 0.784/0.12, P-T interval = 0.584/0.06, TP segment = 0.195/0.09 and
heart rate = 78.43/12.13. Mean electric axes (ventricular complex) was = -
85,17/8,71 degrees. Compared to the
previous studies that examined 82 animals, the values displayed by the ECG
components were relatively the same and the duration was similar to those
studied before.
The
electrocardiography is a method frequently used in the diagnosis of
cardiovascular diseases such as arrhythmias, while offering useful information
for the diagnosis of the enlargement of the heart cavities, pericardial
collection, electrolyte disturbance etc.
However, when
performing the electrocardiogram on cattle in three standard limb leads, it
does not offer an adequate tracing. Thus, more leads systems were proposed. We
studied Dubois system that, compared to the standard limb leads, provides a “clean” trace, with amplitude
waves easy to evaluate, while the practical registration is simply performed.
The present study
aimes to estimate the duration and amplitude of the ECG components in adult
cows, clinically healthy.
Material and Methods
Research was
performed on a number of 207 clinically healthy cows, metis breed Holstein; age
ranging between 4 to 8 years old and weight between 400 to 450 kg.
The ECG were
performed on animals in quadrupedal position, restrained by simple binding.
The work
parameters were: the amplitude of the millivolt = 10 mm and the paper speed was
25 mm/sec.
The sites for
electrodes application was not sheared but only moisten with alcohol solution.
The cable were attached with alligator
clips.
The suitable sites
for the attachments of the exploring electrodes were:
-
Red electrode (right anterior limb) –
anterior of the right shoulder;
-
Yellow electrode (left anterior limb) –
in front of the left shoulder;
-
Green electrode (left posterior limb) –
ventral, on the midline, between the xiphoid process and umbilicus;
-
Black electrode (indifferent connection)
– outside the triangle formed by the other three exploring electrodes (on the
neck side) (figure 1).
Figure
1. Dubois leads system
Results and Discussion
The study analyzed:
-
The values of the ECG components in
Dubois leads system;
-
Changes of the ECG values indifferent
physiological conditions.
The bovines’ electrocardiography shows P and T
waves positive in the opposite side of the ventricular complex (see Figure 2).
Figure
2. The cattle`s electrocardiogram
.
The values of the
components in Dubois system, in adult cows, are shown in table 1 – 3.
Table
1. Amplitude of ECG waves in Dubois system in adult cows
(n. =
207)
mV
|
I.
|
II.
|
III.
|
“aVR”
|
“aVL”
|
“aVF”
|
|
P
wave
|
n.
Average
S.
deviation
|
114
0.029
0.040
|
199
0.177
0.059
|
198
0.136
0.044
|
190
0.106
0.060
|
186
0.043
0.066
|
196
0.158
0.044
|
Ventricular
complex
|
n.
Average
S.
deviation
|
153
0.179
0.122
|
204
1.176
0.279
|
203
1.217
0.286
|
198
0.535
0.192
|
199
0.706
0.189
|
200
1.235
0.282
|
T
wave
|
n.
Average
S.
deviation
|
117
0.038
0.050
|
202
0.453
0.160
|
203
0.450
0.152
|
195
0.215
0.070
|
196
0.215
0.073
|
198
0.464
0.155
|
Table
2. Duration of ECG components in Dubois system in adult cows
(n.=
207)
Duration
(sec.)
|
||
P
wave
|
n.
Average
S. deviation
|
204
0.085
0.013
|
P-R
interval
|
n.
Average
S. deviation
|
204
0.199
0.025
|
Ventricular
complex
|
n.
Average
S. deviation
|
206
0.081
0.011
|
Q-T
interval
|
n.
Average
S. deviation
|
206
0.383
0.040
|
T
wave
|
n.
Average
S. deviation
|
205
0.095
0.021
|
R-R
interval
|
n.
Average
S. deviation
|
205
0.784
0.121
|
P-T
interval
|
n.
Average
S. deviation
|
203
0.584
0.068
|
TP
segment
|
n.
Average
S. deviation
|
203
0.195
0.096
|
Heart
rate
|
n.
Average
S. deviation
|
205
78.430
12.131
|
Table
3. Values of the electrical axes in Dubois system in adult cows
(n. =
207)
Electrical
axes (°)
|
||
P
wave (+)
|
n.
Average
S. deviation
|
200
76.645
14.326
|
Ventricular
complex (-)
|
n.
Average
S. deviation
|
201
85.174
8.716
|
T
wave (+)
|
n.
Average
S. deviation
|
200
89.925
9.523
|
The
electrical axes extreme deviation (changing the sense) were excluded
During the
examination we noticed the following situations:
When the animal
adopted sternal position, the values of ECG components, especially those of the
amplitude, changed as a consequence of changing the heart electrical axes (as
the heart topography in the thorax changes when the animal is lying down).
Another situation
was noticed when the position of the head and the neck has been changed.
Turning the head to the left or right visibly modifies the amplitude of ECG
trace and less the heart rate, which can be accounted to the compression of
carotid sinuses.
During the
examination, the position of the electrodes was changed. They were attached in
a lateral or more anterior position, describing a circle of approximate 10 cm
diameter. No changes of the wave amplitude were noticed.
When feeding the
animal, the heart rate slightly increased as a consequence of the sympathetic
system stimulation.
Electrical axes
were positive for P and T waves and negative for the ventricular complex. We
noticed positive ventricular complex in
6 animals.
Conclusions
1.
ECG exam was performed on a number of
207 clinically healthy cows, metis breed Holstein; age ranging between 4 to 8
years old and weight between 400 to 450 kgs.
2.
The work parameters were: unipolar and bipolar leads proposed by
Dubois (the first two exploratory electrodes behind the scapulohumeral joint,
the third was placed ventral, behind the xiphoid process, the amplitude, 1
mV=10 mm and the speed was of 25 mm/sec.
3.
The bovines’ electrocardiography shows P and T waves positive in
the opposite side of the ventricular complex.
4.
The values of the ECG components (II-lead; Average/SD) were: A) the amplitude
(mV) of the P wave = 0.177/0.059, the amplitude of the ventricular complex =
1.181/0.27 and the amplitude of the T wave = 0.453/0.15. B) the duration (sec.)
of the P wave = 0.085/0.01, P – R
interval = 0.199/0.02, ventricular complex = 0.081/0.01, Q-T interval =
0.383/0.04, T wave = 0.095/0.02, R-R interval = 0.784/0.12, P-T interval =
0.584/0.06, TP segment = 0.195/0.09 and heart rate = 78.43/12.13. Mean electric
axes (ventricular complex) was = - 85.17/8.71 degrees.
5.
Several physiological aspects (such as the
cattle turning the head to the left or to the right ), alimentation, the cattle
laying on a sterno-abdominal decubitus, etc. lead to minor alterations of the
amplitude of the ECG waves that carry no clinical significance.
References
1.
Amory H., Genicot B., Rollin F., Beduin J.M., Lekeux P., 1993 - Normal electro-
and vectorcardiographic data in the growing Friesian calf using a semi-orthogonal lead system.
Zentralbl Veterinarmed A., 40, 2, 81 - 92.
2.
Blood
D.C., Henderson J.A., 1983 – Veterinary Medicine. Ed. IV.,
Bailiere Tindall, London.
3.
Brăslaşu
M.C., Elena Daniela Brăslaşu, Silvia Joiţa, M. Ghiţă, S. Ionescu, 2008 –
Studies regarding the electrocardiogram in cattles in Dubois lead. Buletin
USAMV, Veterinary Medicine, Cluj Napoca, 65, 2,
155 – 159.
4.
Brăslaşu Corneliu Mihail, Brăslaşu Elena
Daniela, Irinel Georgeta Verman, Ilinca
Săvulescu Fiedler, 2004 - Cardiologie
Veterinară. Examinarea
aparatului cardiovascular la animale. Editura Artprint, Bucureşti.
5.
Lefcourt A.M., Erez B., Varner M.A.,
Barfield R., Tasch U., 1999 - A noninvasive radiotelemetry system to monitor heart
rate for assessing stress responses of bovines.
J. Dairy Sci. 82, 6, 1179-1187.
6.
Meli
F., Catarsine O., 1980 – Electrocardiographic study in calves with new
derivation method. Annali dela Facolta
di Med. Vet. Messina, 17, 81 – 100.
7.
Mendez L.C.N., Camacho A.A., Alves A.L.G.,
Borges A.S., Souza R.C.A., Ferreira W.L., 2001 – Standard electrocardiographic values in
Holstein calves. Arquivo Brasileiro Med. Vet. E Zootecnia, 53, 6, 641 –
644.
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