Journal of Animal Science Advances
Milk Quality of Dairy Cattle Bred in Ceará, Northeast of Brazil
Da Cruz A. M., De Castro E. V., Barbosa F. J. M., Dos Santos H. D., De Souza J. F., Arrivabene
M., Cavalcante T. V., Minharro S., Falcão A. J. D. S. and Dias F. E. F.
J Anim Sci Adv 2014, 4(6): 897-903
DOI: 10.5455/jasa.20140613111614
Online version is available on: www.grjournals.com
ISSN: 2251-7219
DIAS ET AL.
Original Article
Milk Quality of Dairy Cattle Bred in Ceará,
Northeast of Brazil
1
Da Cruz A. M., 2De Castro E. V., 3Barbosa F. J. M., 4Dos Santos H. D., 5De Souza J. F.,
6
Arrivabene M., 6Cavalcante T. V., 4Minharro S., 4Falcão A. J. D. S. and 4Dias F. E. F.
1
Zootecnista, Representante da Tortuga, Bom Jesus-Piaui, Brasil.
2
Médico Veterinário Autônomo, Gurupi, Tocantin, Brasil.
3
Médico Veterinário, Fazenda Teotônio, Madalena, Ceará, Brasil.
4
Universidade Federal do Tocantins, Escola de Medicina Veterinária e Zootecnia, Campus de Araguaína, BR 153, s/n, Zona Rural,
Caixa Postal 128, Araguaína-Tocantins, Brasil.
5
Laboratório Brio-Genética e Biotecnologia, Araguaína-Tocantins, Brasil.
6
Universidade Federal do Piauí, Centro de Ciências Agrárias, Departamento de Clínica e Cirurgia Veterinária, Teresina-Piaui, Brasil.
Abstract
The demand for high quality dairy products is growing, milk should be produced under both sanitary and
technological standards, to ensure maintenance of its nutritional characteristics and meet the required hygienic
aspects. Our objectives were to evaluate the quality of refrigerated fresh milk from cattle, produced in the city
of Magdalena, State of Ceará, Northeast of Brazil, according to the parameters set forth in regulatory instruction
number 51, and compare the quality of milk in different breeding systems. 101 refrigerated fresh milk samples
were collected monthly, from October 2010 to March 2011, directly from the expansion TANKS of three dairy
farms, with different production systems. The samples were collected in vials containing Bronopol (2-bromo-2nitropropane-1,3-diol), packaged and transported in thermal boxes with ice, and sent for analysis to the
laboratory clinica do leite-ESALQ – USP, for total bacterial count (TBC), somatic cell count (SCC), and milk
composition in relation to fat, protein, lactose, total solids (TS), dry degreased extract (DDE) contents. The
patterns of chemical composition of milk, TBC and SCC observed were within the limits established by
regulatory instruction number 51 in all samples, demonstrating that producers adopted hygienic measures for
obtaining and conserving the milk, thus ensuring ITS quality. TN: NI 51 = Regulatory Instruction number 51,
which regulates the production and transport of milk in Brazil.
Keywords: Cattle, milk quality, milking.

Corresponding author: Universidade Federal do Tocantins, Escola de Medicina Veterinária e Zootecnia, Campus de Araguaína, BR 153, s/n, Zona Rural, Caixa Postal
128, Araguaína-Tocantins, Brasil.
Received on: 19 May 2014
Revised on: 02 Jun 2014
Accepted on: 13 Jun 2014
Online Published on: 30 Jun 2014
897
J. Anim. Sci. Adv., 2014, 4(6): 897-903
MILK QUALITY OF DAIRY CATTLE BRED IN …
Introduction
The participation of the Northeastern region in
the national milk production has been gaining
momentum over the last decade. It has been the
second fastest growing milk-producing region in
this period, with a growth of approximately 69%.
The northeast of Brazil currently accounts for 12%
of all milk produced in the country (IBGE, 2008).
In the northeast, the main producing state is
Bahia with 966 million liters per year, followed by
the state of Pernambuco, with 662 million liters per
year. The state of Ceará is the third largest producer
in the region, with an output of 416 million liters
per year, which clearly shows the vocation of the
state for dairy farming (IBGE, 2008).
In 2007, the state of Ceará had 2, 42 million
heads of cattle, and in the same year the number of
cows producing milk was 510, 300, which
represented a mere 21% of the total herd. The
productivity of the herd in 2007 was 816
liters/cow/year (IBGE, 2008).
The demand for high quality dairy products is
ever-growing. Milk must be produced under
sanitary and technological conditions which ensure
the maintenance of its nutritional value and
contemplate all hygienic standards. In order to
produce high-quality, nutritious, healthy milk, all
animals must be free of any illnesses, kept under
clean sanitary conditions and all their nutritional
and comfort needs must be met. Somatic Cell Count
(SCC), as well as fat, protein, lactose and total
solids contents are parameters for the assessment of
the nutritional quality of milk (Gomes, 2004).
The market is becoming increasingly
demanding in relation to the quality of milk; this is
due to the perception of the role played by food and
its components on the health of consumers. Quality
milk must display chemical (total solids, fat,
protein, lactose and minerals), microbiological
(total bacterial count), organoleptic (taste, odor,
appearance) composition, as well as a number of
somatic cells that meet the parameters required
(Zanela et al., 2006)
The physical and chemical aspects of milk
contribute to the characterization of the production
system with regard to the correct feeding of the
animals, as well as possible frauds that may alter its
898
composition. On the other hand, the microbiological
assessment guarantees the control of the hygienic
standards applied in the farms. This is of great
importance, as pathogenic microorganisms can be
transmitted to humans, thus affecting their health, as
well as impairing or preventing the processing of
milk (Correa et al., 2010).
The action of bacteria or their enzymes on milk
components cause several changes in milk and other
dairy products. Such alterations include undesirable
flavors and aromas, reduced shelf life, interference
with technological processes and reduction of
productivity. Bacterial contamination of fresh milk
can occur from the animal itself, humans or the
environment. Except in cases of mastitis, the milk
ejected displays a small amount of microorganisms,
which do not constitute any health hazards (Arcuri
et al., 2006).
It is essential to know the composition of milk
in order to determine its quality, as it defines
various industrial and organoleptic properties.
Quality parameters are increasingly being used to
detect failures in management practices. They serve
as references for the improvement of fresh milk.
The main parameters used by most industrial milk
quality programs are fat, protein, and total solids
contents, as well as somatic cell count (Noro et al.,
2006).
The objective of the present work was to
evaluate the quality of refrigerated fresh milk,
produced from cattle, in the city of Magdalena,
State of Ceará, northeast of Brazil, according to the
parameters set forth in IN 51, and to compare the
quality of the milk in different breeding systems.
Materials and Methods
Location and Animals
The study was conducted in dairy farms in the
city of Magdalena, located in the central hinterland
of Ceará, 180 km from the capital, Fortaleza, at 4° 40° latitude, and 39º -20º longitude. This is a region
of semi-arid climate with an average temperature of
26 ºC, and rainfall between 600/1000 mm per year.
This study included a total of 951 cows
producing milk in three dairy farms with different
production characteristics, hereafter called farm one
(F1), farm two (F2) and three (F3). In F1 the herd
J. Anim. Sci. Adv., 2014, 4(6): 897-903
DIAS ET AL.
was comprised of 561 animals; Gyr-Holstein
/Girolando (Bos taurus taurus-Bos taurus indicus)
crossbreed with blood levels of 5/8 and 7/8, with an
average production of 8500 liters/day, through two
closed-circuit milking machines, where the milk
undergoes rapid refrigeration, and is then stored in
expansion tanks. In F2, the herd was comprised of
280
milk-producing
animals,
Gyr-Holstein
/Girolando with blood levels of 1/2 and 3/8 and
Guzerat-Holstein/Guzolando producing an average
of 3100 liters/day, harvested twice a day, via
automatic milking machines and collection-pail set
on the floor. The milk is kept under refrigeration in
an expansion tank. In F3, the herd was comprised of
97 Guzerat-Pure Breed, which were divided in two
groups as follows: group number 1, comprised of 25
animals, was milked twice a day; the remaining
animals were milked only once a day. Both groups
were manually milked with an average yield of 800
liters/day, and the milk was transferred from the
collection pails to a refrigerated expansion tank.
The milk from all three dairy farms was refrigerated
in expansion tanks, according to the standards set
forth in the respective legislation, ready to be
picked up by the isothermal truck of the processing
plant. Such collection is made every day in the
morning.
In all the farms, milking was conducted
according to the procedures recommended for
obtaining hygienic milk, as per Regulatory
Instruction 51 (IN51). Therefore, the routine
procedures of stripping, doing the stripping cup test,
pre- and post-dipping, sanitization of milkers’
hands, milking parlor, and utensils; as well as
careful monitoring for mastitis detection and
prevention, through the conduction of the California
Mastitis Test (CMT), and any other practices which
ensure the quality of the milk produced were in
effect.
The animals were kept semi-confined and fed
with a mineral concentrate, according to milk
production, receiving 1 kg of concentrate for every
3kg of milk produced. At F1, the animals were
divided into groups, and managed as follows:
groups 01 and 02 received roughage in a proportion
of 60% of the diet, as well as chopped elephant
grass and barnyard grass (Echinochloa crus-galli) in
the trough, and groups 03 and 04 were feed in the
899
J. Anim. Sci. Adv., 2014, 4(6): 897-903
trough and then sent to paddocks in a rotational
system, consisting of pasture of Panicum maximum
grass, Tanzania cultivar. After milking, the animals
from farms F2 and F3, with lower production rates,
received feed which was proportional to their
production, and were sent to pastures with of native
grass and Andropogon, as well as received
supplementation with corn silage, all year round.
Milk Sampling and Analysis
101 refrigerated fresh milk samples were
collected, from October 2010 to March 2011.
Samples were collected monthly, directly from the
expansion tanks of the three farms. For the
assessment of the total bacterial count (TBC);
somatic cell count (SCC) and milk composition, in
relation to fat, protein, lactose, and total solids (TS)
contents, as well as dry degreased extract (DDE),
the milk samples were collected in vials containing
Bronopol
(2-bromo-2-nitropropane-1,
3-diol),
packed and transported in isothermal boxes with
ice, and sent for analysis in the laboratory Clínica
do Leite-ESALQ-USP.
Analysis of Results
Data were tabulated and submitted to
descriptive statistics and analysis of variance using
EpiInfo version 3.5.3 and OpenEpi 2. Values were
analyzed and compared to the standards established
by Regulatory Instruction 51 (IN-51).
Results and Discussion
According Hoogerheide and Mattioda
(2012), milk is among the top six most important
products of Brazilian agriculture, well above
traditional products such as coffee and rice. The
milk and dairy products industry plays an important
role in the food supply and the generation of jobs
and income for the population.
The three dairy farms from which the milk
samples were obtained and analyzed adopt different
milking practices. However, in all of them milking
management procedures are routinely adopted
aiming to improve milk hygiene. According to
Souza et al., (2005), milking is the stage of milk
production which requires more care, due to the
great influence on milk quality. Hygiene procedures
MILK QUALITY OF DAIRY CATTLE BRED IN …
are required for the milking parlor, the milker, as
well as all utensils.
Obtaining milk from healthy cows, in adequate
hygienic conditions, and immediate cooling to 4 °C;
are primary and fundamental measures to ensure the
quality and safety of fresh milk and other dairy
products (Arcuri et al., 2006).
Taking into account the different milking
practices of the three dairy farms, as illustrated by
Table 1, we found that, in relation to milk
composition, the results show that it is possible to
obtain milk that meets the requirements of
legislation, in any production system, provided that
the hygienic procedures are routinely adhered to, as
observed in the three properties studied.
Table 1: Milk composition, fat, protein, lactose, total solids (TS), dry degreased extract (DDE); according to production
system - mechanical close circuit, mechanical with collection bucket at foot, and manual milking- of refrigerated fresh
milk produced by three dairy farms in the city of Madalena, state of Ceará, northeast of Brazil.
Farm /Milking System
Fat (%) Protein (%) Lactose (%) Total Solids (%) DDE (%)
Farm 1
Average
3,40a
3,18a
4,62a
12,15a
8,75a
Mechanical close circuit
Deviation
0,20
0,07
0,04
0,24
0,07
Farm 2
Average
4,04b
3,39c
4,48c
12,88c
8,85c
Manual Milking
Deviation
0,31
0,10
0,05
0,36
0,11
a
b
b
b
Farm 3
Average
3,42
3,60
4,69
12,67
9,25b
Mechanical w/ collection
bucket at foot
Deviation
0,56
0,13
0,07
0,63
0,14
Same letters in a column do not represent significant difference (P>0,05).
The table above shows that, in relation to the
composition of the milk produced, the contents of
fat, protein, dry degreased extract are above the
minimum amounts required by the Regulatory
Instruction 51 (IN-51), which determines 3.0; 2.9
and 8.4%, respectively. Dry degreased extract is
comprised basically of the crude protein, lactose
and mineral contents of the milk (Fonseca and
Santos, 2000).
Data relative to lactose in the present study
(Table 1) are within the required parameters.
According to Gomes et al., (2004) lactose is a
disaccharide formed by glucose and galactose,
corresponding to 52% of dry degreased extract and
is the most stable component of milk, which is
directly related to the volume of milk produced.
According to the regulatory instruction IN-51,
published on September 18 2002, by Ministério da
900
Agricultura, Pecuária e Abastecimento (Ministry of
Agriculture and Food Supply) (Brasil, 2002), in
relation to somatic cell count (SCC) and total
bacterial count (TBC), the maximum acceptable
value in the northeast was initially established at
1x106 cells / mL and 1x106 CFU / mL,
respectively, from July 2007 to July 2010. Between
July 2010 and July 2012, the limit was set at 7.5 x
105 cells / mL and 7.5 x 105 CFU / mL, and after
this period the maximum is 4x105 cells / mL and
3x105 CFU / mL, respectively.
Table 2 and 3 show that the numbers for SCC
and TBC obtained in this study were below the
maximum number permitted by law, with the
exception of F2 which had an elevated SCC, which
was attributed to a possible outbreak mastitis, which
occurred during this period.
J. Anim. Sci. Adv., 2014, 4(6): 897-903
DIAS ET AL.
Table 2: Total bacterial Count (TBC) (x 1000 UFC/mL) according to production system of fresh
refrigerated milk produced by three dairy farms in the city of Madalena, state of Ceará , northeast of Brazil.
Farm /Milking System
Farm 1
Mechanical close circuit
system
Farm 2
Mechanical w/ collection
bucket at foot
Farm 3
Manual Milking
Average
(TBC /mLx1000)
33,54ª
IN-51
(TIC >1x106 UFC/mL
1x106 UFC/mL
466,25b
114,36c
Same letters in a column do not represent significant difference (P>0,05).
According Borges et al., (2009) hygiene
procedures for obtaining milk, such as appropriate
milking management, sanitization of equipment and
proper refrigeration, are important factors for the
reduction of bacterial counts in milk. Such
procedures are strictly carried out in the three dairy
farms object of the present study.
Milk quality is associated with the initial
microbial load in the product, and the higher the
number of contaminants and storage temperature,
the shorter its shelf life will be (Santana et al.,
2001). All the milk produced in the dairy farms
studied was kept under refrigeration. It is important
to emphasize that the cooling temperature of 4 ° to
7°C in a period of up to two hours, is the most
effective procedure for its conservation.
According to Guerrero et al., (2005) it is
important to assess the amount of microorganisms
in milk, as the index of microbial contamination can
be used in the evaluation of its intrinsic quality, as
well as the sanitary conditions of production and the
overall health of the herd. Considering its potential
for multiplication, bacteria can cause chemical
changes in milk, such as the breakdown of fats,
proteins or carbohydrates, which may make the
product unfit for consumption or processing.
Table 3 shows that the values of SCC of F2 are
above the levels recommended by the IN-51. This
fact was reported in the study by Rezende et al.,
(2012) who also observed elevation of the SCC.
According to Santos and Fonseca (2007) milk with
a somatic cell count above 200.000 cells/mL
indicates the presence of mastitis, which reduces the
amount of milk produced by the animal, and
translates into a reduction of the major components
of milk (fat, casein and lactose) and an increase in
concentrations of sodium chloride and whey
proteins. From the economic standpoint, high SCC
in milk represents losses for both the producer and
the dairy industry.
Table 3: Data obtained from Somatic Cell Count (SCC) (x1000 cells/mL) according to production system
of fresh refrigerated milk produced by three dairy farms in the city of Madalena, state of Ceará , northeast
of Brazil.
Farm /Milking System
Somatic Cell Count (SCC)
Average
IN-51
(SCC x1000/mL)
(1x106 cell/smL)
Farm 1
257,27ª
Mechanical close circuit system
Farm 2
1158,64c
1x106 Cell/mL
Mechanical w/ collection bucket at foot
Farm 3
368b
Manual Milking
Same letters in a column do not represent significant difference (P>0,05).
901
J. Anim. Sci. Adv., 2014, 4(6): 897-903
MILK QUALITY OF DAIRY CATTLE BRED IN …
SCC is the most accurate instrument for
assessing the health of the mammary gland. A SCC
level lower than or equal to 300000 cells ml-1 is
considered normal, for the mixing tank; values
higher than one million mL-1 cells point to the
occurrence of mastitis (Zanela et al., 2006 ).
It is worth pointing out that the data for TBC
and SCC shown in this study; (Table 2) and (Table
3) respectively, obtained between October 2010 and
March 2011, and are in agreement with the values
set forth in IN-51, which was first implemented in
the northeast in July of 2007. The tables show that
the values of SCC and TBC in the three dairy farms
were consistent with the limits set forth in the
legislation, except for the SCC at F2, due to the
mastitis events mentioned above.
The quality of fresh milk is influenced by
multiple factors, among which are husbandry,
handling, mammary gland health, nutrition and the
genetic potential of the herd; as well as other factors
related to the procurement and storage of freshly
harvested milk. Physical, chemical, microbiological
and sanitary parameters are used by industries to
verify and determine the quality of milk. Somatic
cell count, psychrotrophic microorganisms and
antibiotic residue assessment, for example, are
increasingly being used as quality parameters
(Guerreiro et al., 2005).
According Hoogerheide and Mattioda (2012),
many benefits can be achieved by increasing the
quality of milk from dairy farmers to consumers.
Farmers benefit from the improvement in milk
quality, and the resulting possibility for obtaining
more profit. For the dairy industry this will translate
into more efficiency in the manufacturing process.
As for the government, the benefits rest in exporting
dairy products, which will ultimately also benefit all
consumers who will enjoy safe and contaminantfree products.
Further, point of care diagnostic techniques
could be used to check the quality of milk at the
dairy farm (Liu et al., 2011; Cui et al., 2013; Li et
al., 2014; Wadhwa et al., 2012a; Wadhwa et al.,
2012b). Continous monitoring of the quality of
milk, molecular epidemiology, phylogenetic
analysis and mathematical modeling should be
implemented in developing nations (Kumar et al.,
2013; Massaro et al., 2013).
902
Conclusions
In all dairy farms studied, milk chemical
composition standards were within the limits
established by Regulatory Instruction number 51,
thus demonstrating that producers have adopted
hygienic measures in obtaining and preserving milk.
During this study, the geometric means for
SCC and TBC were in accordance legislation
requirements, except for one farm.
The consequence of adopting such procedures
is milk produced according to the current quality
parameters established by MAPA (Ministry of
Agriculture and Food Supply). The refrigeration of
milk immediately after it is harvested is an
important tool, and the procedure is identified as
one of the most significant to maintain quality, even
in dairy farms with different production systems,
which demonstrates that with the adoption of
hygienic production practices, it is possible to
adhere to regulatory standards and obtain quality
milk.
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