time spent on chewing and also increase feed intake [9, 210-240]. The size of the
particle feed has an effect on the duration of chewing - long fodder feed proportions
significantly increase chewing time compared to the shredded feed. In this case, the
consumption of dry matter increases if the length of particles, such as corn silage,
decreases [10, 120-132]. According to some authors [11, 802-810], animals that
consume feeds with smaller sizes of coarse food particles show more chaotic chewing
activity during the day.
Research [4, 215-227; 12] indicate that a higher fiber content increases the
required chewing time per kilogram of consumed dry matter due to slow hydration,
low fermentation rate and high stiffness of the fibers. The connection between the size
of the particle feed and the time of rumination is also confirmed by a decrease in the
number of feed balls processed for a minute of chewing [11, 802-810; 13]. The "gross"
food and the larger size of its particles, the higher the level of rumination in the animal
that consumes it [14, 1947-1957].
Knowing the size of the particle feed, as well as their ratio and specific gravity, is
a key factor in understanding the potential of the so-called "effective fiber" - NDF.
Large particles of coarse fodder are great for stimulating rumination, but if they are too
large, there is a risk of sorting feed in the feed mix. Conversely, if the food particles
are too small, they will pass freely through the scar without stimulation of rumination
[15].
Studies have proved that the physiologically determined flow of gum process is
one of the main features of the optimum functional state of the cow organism [16, 17].
Changes in resting activity are the earliest signal that can be considered as a warning
of potential cow health problems. That is, chewing activity is one of the methods of
control
and
diagnostics
of
health
problems
in
ruminants.
Investigating the relationship between chewing activity and metabolic health of cows
[17], the researchers concluded that chewing activity is the most reliable indication of
comfort, and more importantly, the health of cows. Cows usually chew on average 450-
500 minutes per day. When the rhythm is lowered it is an obvious sign that the cow is
uncomfortable and probably has health problems. Reducing rumination often results in
lower productivity. That is why the method of early diagnosis of health problems can
be monitoring the chewing process. Thus, experimentally, the presence of changes in
chewing activity in cows suffering from ketosis was proved, therefore chewing activity
monitoring can be used as a preventive method against exacerbation of this disease. By
reacting timely to changes in the chewing activity of cows can significantly reduce the
decline in their productivity. However, it should be noted that available information on
the prediction of chewing activity of cows is limited, despite the fact that such
information would help to detect deviations in chewing activity and feed in relation to
diseases and other situations that threaten the well-being of animals. Currently,
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