RESULTS AND DISCUSSION
Recently, crossbreeding, as an element of
commercial herds improvement, has been studied
mainly from the point of view of its influence on
productive and reproductive features, qualitative
composition of milk and duration of economic use
of cows. Furthermore, the study of protein and
mineral composition of crossbred cows’ milk,
which is mostly local or continental, was not
carried out in full. Currently, there is no
information about the influence of crossbreeding
on the protein composition of the cows of the
Holstein breed with the Jersey, Montbeliarde or
Brown Swiss breeds. However, Decow et al.
(2007) noted that the first generation of Holstein
and Jersey crosses was marked by higher levels of
fat, protein, and lower somatic cells. These factors
level the difference in productivity, which was
somewhat higher in purebred Holstein cows.
This is to some extent coincides avoid we in
which the crossbred cows of the first generation
of UBS with Brown Swiss breeds cows
synthesized more fat+protein per lactation, and
had a higher indicator of theoretically possible
yield of rennet cheese than of pure-breed ones.
Pure UBS and URS cows produced 106.45 and
218.36 kg more milk than crossbred analogues per
305 days of lactation, thereby emphasizing the
potential loss of some milk volume associated
with crossbreeding (Table 1).
At the same time, the mass fraction of fat
and protein were higher at crossbred cows by 0.08
and 0.15% at the crossbreed of UBS with Brown
Swiss breeds and by 0.16 and 0.22% at the
crossbred cows of the URS with Montbeliarde
breeds, respectively. Also, the synthesis of
fat+protein was 7.04 kg more UBS and Brown
Swiss breeds and 8.74 kg more at URS and
Montbeliarde crossbred cows.
Research results by Heins and Hansen
(2012), who studied the influence of the
crossbreeding cows of Holstein and Montbeliarde
breeds on productivity, the qualitative
composition of milk and calf crop in 6
commercial California herds, reported that during
305 days of lactation the crossbred cows
synthesized less fat and protein by 3% than
purebred Holstein cows. The authors recommend
to use this combination of crossbreeding for
increasing of the annual calf delivery, reducing of
the risks associated with the severity of calving
and improvement of the udder shape and to use it
in herds with average productivity. Our studies do
not inconsistent with the above mentioned, as at
the crosses of the URS with Montbeliarde breeds,
when we have observed the results of fat and
protein by 1.96% higher and by 1.49% higher
than of theoretically possible yield of rennet
cheese than pure-breed analogues.
An important indicator which marks the
value of milk as a feedstock for food production is
its mineral composition (Cashman, 2006; Patra et
al., 2008; Claeys et al., 2014). The major mineral
elements of milk are biologically significant
constituents that are necessary for normal
development and livelihoods (Stawars et al.,
2007; Cofani et al., 2012; Gürbay et al., 2012).
The number of major mineral elements in milk is
an important indicator of its biological activity.
They are essential for the development of the
aroma – they form bacteria that produce aromatic
substances that are involved in the creation of the
aroma of cultured milk foods, sour cream butter,
as well as in the formation of a picture in cheese
(Schöne et al., 2009; Rafiq et al., 2016). In
addition, they are part of the buffer systems of
milk and casein micelles.
The most important major mineral elements
of milk are calcium and phosphorus. They are
contained in an easily digestible form and
harmoniously balanced among themselves
(Tripathi et al., 1999; Moreno-Montoro et al.,
2015). The physiological and biochemical role of
Ca and P is very important in human nutrition,
especially for children, in the processing of feed
stock and plays a pivotal role in the dispensing of
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