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on the farm. The main feeds were: hay, haylage and concentrates. Feeding norms during the
period of scientific research corresponded to the breed, live weight and physiological condition
of the bulls.
In the research work, the EXAGO scanner, developed using the latest technologies and
adapted to use in the field of animal science, was used to determine the lifetime quality of meat.
The sensors of the device have three operating frequencies, when switching which it is possible
to optimize the image for each specific case. The loading time of the device is 30 seconds.
Images and clips can be stored in internal memory or on a USB device. The ultrasound scanner
is based on digital technology, including
a built-in processor and FPGA, EXAGO.
Determination of the thickness of subcutaneous fat and the area of the muscular eye in
animals was carried out at the age of 12-14 months. The area of the muscular eye was measured
by drawing a contour in the resulting figure. The thickness of the fat on the back was obtained
from a distance of ¾ of the maximum muscle height between 12-13 ribs using an EXAGO
ultrasonograph.
The final type of non-restrained test can be measured in two parts. The first is a flight score.
This is a subjective score given to an animal based on its behavior upon exiting the chute. Again,
there is no widely adopted version of this test, but the score is often assigned based on a four-
point scale (4-walk; 1-jump). In conjunction with a subjective score, an exit velocity or flight
speed can also be recorded. This technology was first introduced by Burrow et al. [6] to record
the time taken for animals to cover a predetermined distance upon exiting the chute, or other
confined area. The predetermined distance of 1.7 meters was selected as it is slightly shorter
than the chute. Exit velocity is believed to be a more objective measurement of temperament in
comparison to exit score or any other categorical variable.
The place of research is Akmola region, Republic of Kazakhstan.
The study period is
November 2022 - February 2023.
The tests were carried out in the morning before the feed was distributed, and at the time
of the tests, the humidity was 80%, the pressure was 756 mmHg, the wind speed was 4.1 m/s
and the temperature was 13 °C. To obtain descriptive statistics, the standard MS Excel add-in
"Analysis Package" was used - a tool for analyzing descriptive statistics, into which sets of
primary data for the studied years were transferred. The table below are data on the relationship
between the temperament of bulls and the area of the muscular eye (Table 1).
Table 1. The relationship between the temperament of bulls and the ribeye area (n-47)
Temperament
The ribeye area M±m, cm2
Сv,%
δ
Max
Min
4
48,3±1,6
16
5,5
63,6
36,2
3
44,5±1,9
18
7,0
57,3
34,5
2
40,9±1,0
11
3,4
49
32,4
1
37,2±0,8
10
2,9
44
30,9
During the tests, it was found that the area of the muscular eye of steers with a calm
temperament (4) was 48.3 ± 1.6 cm2, and in steers with temperament 3 was 44.5 ± 1.9 cm2,
which is 7.9% less compared to steers with a calmer temperament. The areas of the muscular
eye of bulls with temperament 2 and 1 were 40.9±1.0 cm2 and 37.2±0.8 cm2, respectively. The
most aggressive bulls (with temperament 1) in terms of the area of the muscular eye, they were
inferior to their peers with the most calm temperament by 23%. In other words, there is a high
positive correlation between the types of temperament of bulls and the area of the muscular eye,
which is also confirmed by studies by other authors (Aline Cristina Sant'Anna, Tiago da Silva
Valente) [7]. The following are data on the relationship between the temperament of bulls and
the thickness of subcutaneous fat (Table 2).
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Table 2. The relationship between the temperament of bulls and the thickness of subcutaneous
fat (n-47)
Temperament
Thickness of subcutaneous
fat M±m, mm
Сv,%
δ
Max
Min
4
3,1±0,3
21
0,54
4,34
2,51
3
2,9±0,3
25
0,60
4,1
1,67
2
2,8±0,3
23
0,51
4,01
1,67
1
2,8±0,2
19
0,46
3,34
1,67
According to the table, it can be noted that the largest thickness of subcutaneous fat in bulls
with temperament 4 and is equal to 3.1 ± 0.3 mm, and in bulls with temperament 1, the thickness
of subcutaneous fat was 2.8 ± 0.2 mm, which is 9.7% less compared to the most calm peers.
While, the thickness of subcutaneous fat of bulls with temperaments 2 and 1 was at the same
level. The thickness of subcutaneous fat of steers with temperament 3 was 2.9± 0.3 mm, which
is 3.5% more compared to more aggressive steers. It should be noted that there is also a positive
correlation between the types of temperament of bulls and the thickness of subcutaneous fat.
Some studies show that the temperament of bulls affects the thickness of subcutaneous fat
and other characteristics of the carcass [8].
In conclusion, the results of these studies show that there is a positive correlation between
the types of temperament of bulls and meat qualities, such as the area of the muscular eye and
the thickness of subcutaneous fat.
The types of temperament of bulls can serve as an important criterion for breeding selection
in order to preserve and improve meat qualities.
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