351 Analele Universității din Oradea, Fascicula: Ecotoxicologie, Zootehnie și Tehnologii de Industrie Alimntară Vol. XIV/A, 2015 THE EFFECTS OF BREED… [601779]

351 Analele Universității din Oradea, Fascicula: Ecotoxicologie, Zootehnie și Tehnologii de Industrie Alimntară Vol. XIV/A, 2015

THE EFFECTS OF BREED ON CONJUGATED LINOLEIC ACID
(CLA) AND OTHER FUNCTIONAL LIPID COMPONENTS OF
SHEEP MEAT AND ADIPOUSE TISSUE

Mierlita Daniel

University of Oradea, Faculty of Environmental Protection, 26 Gen. Ma gheru St., 410048 Oradea,
Romania, e-mail: [anonimizat]
Abstract
This study was conducted in order to evaluate the influence of race on content of functional
fatty acids (Omega-3, conjugated linoleic acid-CLA, trans-Vaccenic acid-VA) in lamb carcass fat, in
similar feeding. In this regard, the research was carried out on three local breeds which are better
represented in the northwest of the country: Turcana, Tigaie and Transylva nian Merino. In the case
of Tigaie breed we monitored the impact of fat type (intramuscular vs. fat de posit), and the body part
for harvesting purposes (longissimus dorsi vs. biceps femoris and subcutaneous fat vs. perirenal fat).
Livestock were sacrificed at the end of the 60 days fattening perio d, ant it was set the fatty acid
composition of the intramuscular fat in longissimus dorsi muscle. Significant differen ces were
detected in the acid content of polyunsaturated fatty acids (PUFA) and satura ted fatty acids (SFA) of
intramuscular fat in favor of Tigaie breed. Differences were noticed between breeds in terms of
content in Omega-3 FA, and in the content of conjugated linoleic ac id (CLA), with higher levels in
Tigaie breed lambs as against the other two breeds studied. The share of va ccenic acid (C18:1 trans-
11) in the intramuscular fat structure was not influenced by breed, this FA being an intermediate
product of ruminal biohydrogenation of PUFA in food. In general, th e findings showed that
intramuscular fat in Tigaie breed lambs were healthier for human consumption due to low content in
saturated fatty acids (SFA), and higher in functional fatty acids, i.e . FA n-3 and CLA which suggest
that the Tigaie breed could be used to produce sanogeneous sheep meat.

Key words: Breed, type of tissue, Omega-3 FA, CLA, Atherogenicitiy index

INTRODUCTION

Conjugated Linoleic Acid (CLA) is a general term used to define
more geometric and positional isomers of octadecadienoic acid containing a
pair of double chains in a conjugated configuration. In experimental
livestock models it has been shown that CLA, but especially the cis-9, trans-
11 CLA (also called rumen ic acid) has beneficial effects in the human body,
reducing carcinogenesis, atherosclerosis, cholesterol, diabetes and the
weight of body fat (Belury 2002; Ip et al., 1999; Lee et al., 1994; Parodi,
1997). The main source of CLA for human body and especially in rumen
acid which represents 80-90% of the total CLA isomers is the food derived
from ruminants (milk, dairy products and meat). The rumenic acid (RA, cis-
9, trans-11 CLA) is formed as an intermediate product during ruminal
biohydrogenation of linoleic acid in the food and its transformation into
stearic acid (C18:0), or is formed by the endogenous synthesis in the body
tissue, using as the vaccenic acid (VA, C18: 1 trans-11) as substrate, which

352 is also formed during the process of ruminal biohydrogenation of the fatty
acids in the diet (Grinari and Bouman, 1999).
In human nutrition, along with CLA and VA, two other fatty acids are
considered important for health, i.e. linoleic acid (C18:2n-6, LA) and α –
linolenic acid (C18:3n-3, ALA). These essential FA have an important role
in the prevention and control of cardiovascular diseases, the development
and proper functioning of the nervous system, prevention of rheumatoid
arthritis, but they also serve as precursors to a number of other bioactive
compounds which are important to the health of consumers. Thus, the α-
linolenic acid is a precursor for other fatty acids of the Omega-3 series
(EPA-ecosapentaenoic acid, C20:5n-3 and DPA-docohexaenoic acid ,
C22:6n-3), with the participation of specific desaturases.
The share and proportion of fatty acids in animal fats are determined
primarily by nutritional factors, but they may be influenced by a number of
genetic (breed) or physiological factors (body weight and slaughter age, sex ,
type of fat: intramuscular or deposit region, body region, etc.) (Wood et al.,
2008). Breed may influence the fatty acid profile of intramuscular and
deposit fat in ruminants. This finding was not confirmed by Radzik-Rant et
al. (2014) who found that breed (genotype) did influence the concentration
of MUFA (monounsaturated fatty acids) in intramuscular fat of lambs and
not that of PUFA, as expected. The authors have reached the conclusion that
primitive breeds deposit less intramuscular fat and the fatty acid profile is
more favourable to consumer health compared with improved genotypes
which deposit more fat in the carcass, the latter being richer in MUFA and
SFA.
The main purpose of this research was to investigate the relations
between some internal animal dependent factors (i.e.breed) and the
functional content of fatty acids (i.e. Omega-3, CLA and VA) of fat in sheep
carcass. In this respect research was carried out on three local breeds which
are better represented in the northwest of the country: T urcană, Tigaie and
Transylvanian Merino. In the case of Tigaie breed one studied the influence
of the fat type of (intramuscular vs. fat deposit), but also the harvesting
regions ( longissimus dorsi vs. biceps femoris and subcutaneous fat vs.
perirenal adipouse tissue ).

MATERIAL AND METHOD

In the case of sampling (muscle and adipouse tissue ) for analysis
purposes there were used 24 samples of young lambs from commercial
farms, distributed as follows: four rams and four females for each of the
three breeds studied (Tigaie – Ti, T urcană – Tu, and Transylvanian Merino-
TM). 60 days prior to sampling for analysis and slaughter purposes,
respectively, in the diet of animals, there were used fodder uniform structure

353 based on natural hay and combined fodder while observing the specific
nutritional requirements. Hay was provided ad libitum and fodder combined
were administered twice a day i.e. 400 g per capita. Thus it was eliminated
the influence of food on the fatty acid profile of the carcass.
Slaughtering for control purposes was preceded by a 12 hours diet and
sampling for analysis purposes from Longissimus dorsi muscle, biceps
femoris and perirenal and subcutaneous adipouse tissue was made the next
day of slaughtering after carcass drying (24 hours at 4°C ). In order t o
establish the fatty acid profile of the carcass, sampling of individual muscle
(longissimus dorsi – lower back and biceps femoris ) and adipouse tissues
(subcutaneous – lower back and perirenal) was performed. The samples
were individually packed in plastic bags and stored at -20°C before analysis.
Extraction of lipids was carried out with a mixture of chloroform:
methanol (2:1 vol./vol.), and the fatty acids methyl esters (FAME) were
prepared using boron trifluoride (BF3) and methanol (14% w /w), as
described by Watkins et. al. (1997). In order to quantify the isomer of
conjugated linoleic acid (CLA), lipids extracted from tissue samples were
methylated (sodium methoxide) based on the procedure described by Li and
Watkins (1998). The lipids were dissolved in toluene (1ml) in a Teflon tube
with a screw cap. FAME were identified using HP 5890 gas chromatograph
equipped with a 30 m length DB23 column. Gas chromatograph was run at
140°C for 2 min., the temperature increasing by 1.5°C/min. up to 198°C and
then held for 7 minutes. CLA isomers were further analyzed using a 100 m
length SP2560 capillary GC column. For each operation with gas, the
chromatography, injector and detector with flame ionization showed
temperatures ranging between 225°C and 250°C. FAME were identified by
comparing their retention time against the standard.
All laboratory test results were statistically processed and interpreted,
using the SAS procedure (version 8.0; SAS Inst., Inc., Cary, NC) for
repeated measurements and the 't' test. Differences were considered
significant for p <0.05.

RESULTS AND DISSCUSIONS

The effect of breed on fatty acid profile was set for intramuscular fat
in longissimus dorsi muscle (LD). TM lambs breed meat had an
intramuscular fat content almost doubled compared to that of Ti breed
which recorded the lowest share of fat in LD. Similar results were obtained
by Borys et al. (2005)in the case of primitive breeds compared with the
improved breeds, but they were not confirmed by Martinez-Cereso et al.
(2005) who found no differences between different genotypes in terms of
LD muscle fat content. The amount of cholesterol per 100 g intramuscular

354 fat was not influenced by race, being highlighted, however, the lower share
recorded in Ti breed (see Table 1 below ).
The predominant fatty acids in the intramuscular fat all three breeds
were as follows: palmitic acid (C16:0), stearic acid (C18:0) and oleic acid
(C18:1 cis).
Among saturated fatty acids (SFA), the largest concentration of
palmitic acid and stearic acid in intramuscular fat was registered in T M
breed lambs. The total content of SFA was lower in intramuscular fat in
breeds with a low degree of improvement i.e. Ti and Tu, no significant
differences between them being recorded.
Out of the total monounsaturated fatty acids (MUFA) in all three
races, the oleic acid represented more than 90%, the highest concentration in
intramuscular fat composition being recorded in the TM breed. However,
among the three races there were no significant differences in the total
MUFA content in intramuscular fat. In contrast to our results, Radzik-Rant
et al. (2014) found that breed (genotype) influenced the concentration of
MUFA (monounsaturated fatty acids) in intramuscular fat of lambs and did
not affect the PUFA content, as expected.
The data showed in Table 1 show that, out of the three breeds studied
(i.e. Transylvanian Merino-TM, T urcană -Tu, Tigaie-Ti), the highest share of
fatty acids function (n-3 FA and CLA) in longissimus dorsi muscle was
recorded in Ti breed while Turcana breed was placed the lowest in his
ranking . In the case of Transylvanian Merino, n-3 PUFA and CLA values
were very close to those found in Tigaie breed, but in the case of TM breed
a higher content of saturated fatty acids (47.54% vs. 43.97% of FAME) was
recorded. The content of fat in intramuscular trans-vaccenic acid (VA,
C18:1 trans-11) was not influenced by the breed, this being a fatty acid
generated during ruminal biohydrogenation of polyunsaturated fatty acids,
in particular the linoleic (C18:2n-6) and linolenic (C18:3n-3) acids in the
diet (Chilliard et al., 2003). The high concentration of C18:2n-6 and
C18:3n-3 and the low concentration of palmitic acid (C16:0) in the
composition of intramuscular fat in the Tsigai breed resulted in a
PUFA/SFA ratio which is more favourable to the health of consumers.
The high content of n-6 PUFA in Tsigai breed is due largely to the
high content of linoleic acid in intramuscular fat. Moreover, in the case of
this breed, the high content of C18:2n-6 improved the synthesis of
arachidonic acid (C20:4n-6) in the intramuscular fat. These findings on the
content of n-6 PUFA in the intramuscular fat in the Tigaie breed are similar
to those reported by Fisher et al. (2000) for the Soay breed lambs when
compared to the Suffolk breed lambs showed higher concentrations of n-6
PUFA in the semimembranosus muscle.

355 Table 1
The influence of breed on fatty acid composition and sanogeneous lipid
indices of intramuscular fat ( longissimus dorsi )
Transylvanian
Merino- TM Turcana- Tu Tsigai- Ti
Total lipids g/100g 6,71b 5,17ab 3,76a
Cholesterol mg/100g 63,6 62,4 61,2
Fatty acids profile (% din FAME)
C12:0 2,17 1,95 1,81
C 14:0 5,04 4,90 5,13
C 16:0 18,67b 16,64a 16,79a
C 18:0 23,83 22,91 22,05
C 16:1 4,59b 3,36a 3,22a
C 18:1 cis 1 27,62b 25,41a 25,06a
C 18:1 trans-11 (VA) 3,33 3,68 3,69
C 18:2 n-6 trans 3,29ab 2,91a 3,74b
C 18:2 n-6 cis 4,80 4,28 4,95
C 18:2 c9, t11 0,89a 1,04a 1,94b
C 18:2 t11, t13 0,15 0,18 0,21
C 18:2 t10, c12 0,35 0,29 0,23
C 18:3 c9, c12, c15 n-3 2,88a 2,80a 3,79b
C 20:2 n-6 1,81a 2,27b 1,68a
C 20:4 n-6 2,92b 2,18a 3,04b
C 20:5 n-3 EPA 1,88ab 1,42a 2,01b
C 22:3 n-3 0,36 0,36 0,41
C 22:5 n-3 DPA 0,33 0,35 0,33
C 22:6 n-3 DHA 1,58ab 1,04a 1,90b
SFA 47.54b 44.45a 43.97a
MUFA 30.95b 29.09ab 28.75a
PUFA 19,85b 17,61a 22,25b
PUFA n-6 12,82b 11,64a 13,41b
PUFA n-3 7,03b 5,97a 8,84b
CLA – total 1,39a 1,51a 2,38b
Health lipid indices
PUFA/SFA 0,42a 0,40a 0,51b
n-6/n-3 PUFA 1,82b 1,95b 1,52a
HFA 25,88b 23,49a 23,73a
h/H 1,96 1,99 2,15
AI 0,81b 0,82b 0,76a
TI 1,03b 1,07b 0,84a
DI (18:2 c9,t11) 21,08a 22,03a 34,47b

356 1 C 18:1 cis = C 18:1 cis 9 + C 18:1 cis 11 + C 18:1 cis 12 ; AI: indexul aterogenic (AI =
(C12:0+(C14:0x4)+C16:0)/UFA); TI: indexul trombogenic
(12:0+16:0+18:0)/[(0.5×MUFA)+(0.5×n-6PUFA)+(3×n-3PUFA)+(n-3PUFA/n-6PUFA )];
VA: acidul trans-vaccenic (C18:1 t11); CLA: acidul linoleic conjugat (izomerul C 18:2
c9,t11); h/H: raportul acizilor grasi hipocolesterolemianti/hipercolesterolemianti
(C18:1+PUFA)/(C12:0+C14:0+C16:0; DI (18:2 c9,t11): indexul Δ9-desaturaza (18:
c9,t11)=100(18:2 c9,t11/(18:2 c9,t11 + 18:1 t11)).

This finding may result from the low concentration of total lipids in
muscle and a higher proportion of phospholipids in total fat structure.
Various amounts of Omega-3 intramuscular fat in the lambs of the three
breeds studied indicate the presence of different amounts of phospholipids
in the muscles and a different metabolism of linolenic acid (C18:3n-3) to
produce the long-chain fatty acids of the n-3 FA series.
Intramuscular fat had a higher content of α -linolenic acid (C18: 3n-3)
in the case of the Ti breed compared to the other two breeds (3.79 vs 2.80-
2.88%). Similar findings were noticed on the content of long-chain fatty
acids of the Omega-3 series (EPA – ecosapentaenoic acid, C20:5n-3 and
DPA – docohexaenoic acid, C22: 6n-3), which recorded significantly higher
values in the case of Ti breed (see Table 1 above). The lambs of the breeds
Ti and TM showed higher proportions of Omega-6 fatty acids in the
intramuscular fat as against those from the Tu breed where one recorded the
lowest functional concentrations of lipid components.
The breed influenced significantly the content of intramuscular fat in
CLA and, in particular, in rumen acid (c9, t11 CLA) and which were
significantly higher in the case of lambs of the Ti breed (Ti ˃ Tu ˃ TM).
Isomer t10, c12 CLA showed higher concentrations in the case of lambs of
the TM breed, but the differences were not statistically consistent.
In conclusion, the breed has a significant influence on the FA profile,
the intramuscular fat in the case of lambs of Tigaie breed shows the highest
concentration of fatty acids (especially ALA, CLA, EPA and DHA), the
lowest content of saturated fatty acids (SFA) and the best sanogeneous lipid
indices (the ratio n-6/n-3 FA, AI and TI). Consequently, the Tigaie breed is
a genetic resource that could be used effectively in the sustainable
production systems to produce sanogeneous sheep meat.
The main lipid indices consider ed in evaluating the quality of
sanogenetic quality of foods with high fat content are as follows: total fat
content, PUFA/ SFA ratio, n-6/n-3 ratio (Department of Health, 1994),
atherogenic index (AI), thrombogenic index (TI) and fatty acid desaturation
index (Ulbricht and Southgate, 1991). In our study, the best values of the
sanogenic lipid indices of intramuscular fat of lambs were obtained from the
Tigaie breed, the differences being statistically consistent. Thus, when
compared to the lambs from the TM and Tu breeds, in the case of the lambs

357 of Ti breed the PUFA/SFA ratio was higher by 30%, while the n-6/n-3 ratio
was lower by 22%, which suggests a more favourable effect on consumers’
health. This is due to the higher proportion of fatty acids in the Omega- 3
series in the structure of intramuscular fat of the Tigaie breed lambs.
Generally, a PUFA/SFA ratio over 0.45 and a n-6/n-3 ratio below 4.0 are
required in the human diet for combating lifestyle related diseases such as
coronary heart disease and cancer (Simopoulos, 2002). Intramuscular fat of
lambs in the Tigaie breed was within such parameters that define the
sanogeneous fat quality, recording a value of 0.51 for the PUFA/SFA ratio
and 1.52 respectively for the n-6/n-3 ratio. The lower concentration of
hypercholesterolemia fatty acids (C12:0, C14:0 and C16:0) and the higher
concentration in the case polyunsaturated fatty acids (in particular for n- 3
PUFA series) in the case of the Tigaie breed lambs led to a significant
decrease in the atherogenic index (AI) and thrombogenic index (TI) valu es.
The improved AI and TI indices were positively correlated with a higher
content of intramuscular fat in functional fatty acids (n-3 FA, CLA).
Atherogenic index (AI) and thrombogenic index (TI) characterize food fats
in terms of impact on consumer health, the fat with a higher value or
atherogenic and thrombogenic index being harmful to human health.
In order to quantify the amount of CLA in intramuscular fat coming
from endogenous synthesis (formed mainly at tissue level) by converting
trans -vaccenic ac id under the action of the enzyme Δ9 – desaturase, we
estimated the activity of this enzyme by means of the desaturation index (DI
18:2 c9, t11) using the equation proposed by Pilarczyk et al., (2015). The
highest desaturation index value (DI 18 2 c9, t11) was found in the lambs of
Tsigai breed, suggesting a high enzymatic activity level and therefore a
larger amount of CLA c9, t11 of intramuscular fat was formed by enzymatic
desaturation of vaccenic acid (C18:1 t11) in various tissues. Thus, these
findings are confirmed by studies developed by Chilliard et al., (2003)
which mention that the activity of desaturases has a breed nature with a
strong genetic determinism. All these changes are consistent with the lower
concentration of stearic acid (C18:0) in the intramuscular fat of Ti breed
lambs ; stearic acid is the final product of ruminal biohydrogenation of
polyunsaturated fatty acids in the diet, and in particular, in the case of
linoleic acid (Chilliard et al., 2007).
Since, in the case of Tigaie breed, we achieved the highest
concentrations of functional fatty acids in intramuscular fat, we carried on
our studies in this breed to determine whether the fatty acid profile is
influenced by the type of tissue (intramuscular fat vs. fat deposit) or body
region ( longissimus dorsi muscle vs. biceps femoris muscle, subcutaneous
adipouse tissue vs. perirenal adipouse tissue ).

358 The fatty acid composition of the intramuscular fat, compared to the
deposit fat is characterized by a lower content of saturated fatty acids (SFA)
and monounsaturated fatty acids (MUFA) and a higher proportion of
polyunsaturated fatty acids (PUFA) (Table 2).
Table 2
Fatty acid profile of different body regions in young fattened sheep, Tsigai
breed (g/100g FAME
Intramuscular fat Adipos fat
Longissimus
dorsi Biceps
femoris p Perirenal fat Subcut. fat p
Total lipides (%) 6,25 11,21 *** 94,9 93,6 NS
C 12:0 0,02 0,02 NS 0,03 0,03 NS
C 14:0 4,60 4,24 NS 2,99 2,45 *
C 16:0 18,87 20,39 * 23,62 17,58 ***
C 18:0 12,29 11,77 NS 18,60 19,64 *
C 20:0 0,12 0,10 NS 0,40 0,36 NS
C 18:1 cis 25,16 27,88 * 35,62 43,95 ***
C 18:1 trans- 11 3,14 3,48 NS 3,56 3,29 NS
C 18:2 n-6 9,74 10,30 NS 4,29 2,78 **
C 18:3 n-3 3,71 5,91 *** 2,68 4,55 ***
CLA total 2,64 2,04 * 1,01 1,98 ***
C 20:2 n-6 0,75 0,81 NS 0,30 0,38 NS
C 20:4 n-6 3,80 5,12 ** 0,83 0,51 **
C 20:5 n-3 EPA 2,69 3,53 * 0,21 0,10 ***
C 22:3 n-3 0,74 0,81 NS 0,04 0,05 NS
C 22:5 n-3 DPA 0,58 0,94 ** 0,21 0,15 **
C 22:6 n-3 DHA 2,64 2,74 NS 0,12 0,07 *
SFA 35,90 36,52 NS 45,64 40,06 **
MUFA 28,30 31,36 * 39,18 47,24 ***
PUFA 27,29 32,20 ** 9,69 10,57 NS
PUFA n-3 10,36 13,93 ** 3,26 4,92 ***
PUFA n-6 14,29 16,23 * 5,42 3,67 ***
DI (18:2 c9,t11) 45,67 36,95 * 22,10 37,57 **

In general, in intramuscular fat the amount of Omega-3 fatty acids was
approx. 3 times higher and the CLA was approx. 2 times higher than in the
case of at deposit. Long-chain polyunsaturated fatty acids (C20 – C22) had
much lower concentrations in the adipouse tissue compared to the muscle
tissue, even by 10-20 times. This can be explained both by the low
proportion of phospholipids in the adipouse tissue and the low rate of
incorporation of long-chain polyunsaturated fatty acids in the triacylglycerol
fraction in ruminants (Ashes et al. 1992; Enser et al. 1996).
The most important differences in the fatty acid profile of the intramuscular
fat were found in the content of ALA, CLA and EPA, in favour of BF
muscle, which also allowed to achieve better sanogenic lipid indices (n-6/n-
3 ratio, AI, TI) when compared to LD muscle related ones (fig. 1 ).

359
00,20,40,60,811,21,41,61,8
PUFA/SFA n-6/n-3 Index Aterogenic Index TrombogenicIntramuscular fat LD
Intramuscular fat BF
Perirenal fat
Subcutaneous fat
Fig. 1. The influence of physiological factors (type of tissue and anatomical
region) on sanogenous lipid indices of carcass fat (LD- Longissimus dorsi ;
BF-Biceps femoris )

In the case of fat depos it, within the subcutaneous adipouse tissue one
recorded a fatty acids profile which is more favourable to human health, and
containing a lower amount of palmitic acid (C16:0), and a higher content of
functional fatty acids (C18:3n-3, long-chain n-3 FA and CLA) as against the
perirenal adipouse tissue.
In humans, trans fatty acids can have adverse effects, leading to higher
levels of LDL ( “bad cholesterol ”) levels and cardiovascular disease
(Department of Health, 1994). Nevertheless, epidemiological studies
(Willett et al., 1993) suggest that monounsaturated trans fatty acids resulting
from the rumen fermentation (especially the trans-Vaccenic acid, C18:1
trans-11) are not risk factors for cardiovascular diseases. Elevated levels of
vaccenic acid in foods derived from ruminant animals can have a positive
contribution to the health of consumers because they turn into CLA at
tissues level in the presence of specific desaturase (Knecht et al. 1996;
Finnegan & Williams, 2001). In the study we conducted one did not find
significant differences in terms of the content of vaccenic acid (18:1 trans-
11) neither from intramuscular deposit fat, nor by anatomical region of body
fat origin. Our results in lambs were confirmed by Maleki et al., (2015) but
are inconsistent with those reported by Schena et al. (2007), who found
significant differences in the concentration of C18:1 trans-11 in the
intramuscular and subcutaneous fat in calves, depending on breed.

360 CONCLUSIONS

The highest proportion of functional fatty acids (c is-9, trans-11 CLA,
C18:3n-3 and long-chain n-3 FA) in the intramuscular (LD) fat composition
was recorded in lambs in the Tigaie breed and, especially, in rams fattened
in intensive fattening system. While monitoring the distribution of fatty
acids in various tissues of the carcass ( longissimus dorsi -LD, biceps femoris
– BF, perirenal and subcutaneous adipouse tissue ) it was found tha t
polyunsaturated fatty acids and the functional fatty acids are found in higher
proportions in the muscle tissue and the saturated ones are found in the fat
deposits and, in particular, in the perirenal adipouse tissue. Of the two
muscles submitted for analysis, the highest amount of Omega-3 fatty acids
was found in the BF intramuscular fat (leg) and the highest amount of CLA
was found in LD. Sheep meat fat content in trans-vaccenic acid (VA, C18: 1
trans-11) which is considered beneficial to human health because it is the
precursor to CLA was not influenced by breed, type of tissue or body
region.

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