Science and Technology [600727]

76 Journal of Food, Agriculture & Environment, V ol.13 (2), April 2015 www Journal of Food, Agriculture & Environment Vol.13 (2): 76-81. 2015 .world-food.net Meri-Rastilantie 3 B, FI-00980 WFL Publisher
Science and Technology
Helsinki, Finland
e-mail: [anonimizat]
Conjugated linoleic acid and ωωω ωω-3 fatty acid in sheep milk was increased by part-time
grazing and camelina seed diet
Daniel Mierlita
University of Oradea, Magheru 26, Oradea, 410087, Bihor, Romania. *e-mail: [anonimizat]
Received 16 January 2014, accepted 28 March 2015.
Abstract
The objective of this study was to investigate the effects of ewes’ feeding system (fed indoor or part-time grazing system) in combination or not with
camelina seed ( Camelina sativa L.) as fat supplement on milk yield and milk fatty acid (FA) composition. Experimental diets were constituted by a
2 x 2 factorial arrangement of feeding system (I: indoors during the entire experiment and received 1400 g DM grass hay/d or PG: grazing – 4 h/day + 700 g DM grass hay/d) and camelina seed (-Cs = no camelina seed vs. +Cs = 140 g/d Cs). All animals received daily 700 g DM concentrate for lactating. Daily milk yield and milk fat yield (p <0.01) were increased by part-time grazing and diets supplementation of Cs. Milk from ewes fed a
part-time grazing had a more favourable fatty acid pattern, high total CLA (conjugated linoleic acid) and n-3 FA content. Suppl ementation of Cs
decreased the short chain FA, medium-chain FA, saturated FA and hypercholesterolaemic FA (HFA: C12:0 + C14:0 + C16:0) in ewes m ilk fat while
increased trans-vaccenic acid ( trans -11-C18:1, TV A), α-linolenic acid (ALA-C18:3 n-3), CLA, EPA (eicosapentaenoic acid), DHA (docosahexaenoic
acid), monounsaturated FA, polyunsaturated FA and long-chain FA in ewes milk fat (p <0.001). Especially, c9,t11-CLA; t10,c12-CLA and ω -3 FA
(ALA + EPA + DHA) in milk fat were highest when ewes fed PG/+Cs diet. The decrease in HFA resulted in the decrease of milk fat atherogenic index
(AI) of PG diet ewes and of those whose diet was supplemented with camelina seed (+Cs). Based on the result, it is suggested that part-time grazing
and supplementation of camelina seed should be an effective method to increase CLA isomers and ω-3 fatty acid in ewes milk fat without negative
effect on lactating performance.
Key words: Sheep milk, cis-9, trans -11 CLA, vaccenic acid ( trans -11-C18:1), α-linolenic acid (C18:3 n-3), atherogenicitiy index.
Introduction
Raising dairy ewes on pasture is justified not only by the low cost of feeding, but mainly by the nutritional and sanogenetic quality
of the milk obtained, as compared to that obtained from housed
ewes fed preserved feed
1. Pasture-fed ewes can have good milk
production if quality grass is available abundantly. Their milk will
have a high content in substances beneficial to human health,
such as n-3 fatty acids (FA), conjugated linoleic acid (CLA) and vaccenic acid (t11-C18:1). CLA is a collective term used for a mixture
of positional and geometrical ( cis or trans ) isomers of linoleic acid
with conjugated double bonds. The major isomers are c9t11 and
t10c12 besides many others. Most prevalent and biologically active CLA isomer is c9t11. The n-3 fatty acids, and more particularly
eicosapentaenoic (EPA; C20:5n-3) and docosahexaenoic (DHA;
C22:6n-3), can reduce the risk of cardiovascular diseases. In experimental animals, CLA has proved to have anticancer and
anti-atherosclerotic effects, as well as anti-obesity action
2.
Although there are several CLA isomers, health benefit effects have been mainly attributed to cis 9, trans 11-CLA
2. The t11-
C18:1 isomer is an intermediate of the ruminal biohydrogenation of C18:2 and C18:3, and it is a substrate for the endogenous
synthesis of c9,t11-CLA (rumenic acid-RA) in the mammary gland via the enzyme ∆
9- desaturase 3.
Turcana sheep breeds are usually raised using pasture as the main source of feedstuffs during lactation, even though indoor feeding is common in Romania. Due to the variability of pasture
availability and quality, hay and concentrates are commonly and
largely used even in pasture-based systems
4. The traditional,
ewes on farms is fed indoor or often on part-time grazing
supplemented grass hay in order to sustain milk production 5.
This feeding management of ewes deteriorates the sanogenetic quality of milk fat by decreasing the content in C18:3n-3, c9,t11-
CLA and t11-C18:1
5, 6. Thus, it is important for farmers to obtain
milk of high nutritional quality. It has been suggested that camelina
seeds ( Camelina sativa L. is a traditional plant in Romanian
agriculture) should be used as strategy in order to avoid the
negative impact on milk FA profile. The camelina seeds were
chosen for this study because of their high content of linoleic and
linolenic acids, and because they proved efficient in increasing the contents of c9,t11-CLA, V A and n-3 FA in cow milk fat
7 and
goat milk fat 8. Another reason was the limited data available on
the effect of camelina seeds on the milk fat FA profile of dairy
ewes. Therefore, the objective of the present work is to evaluate
the effect of the part-time grazing system or fed indoor and camelina seed supplementation in the diet on milk yield and milk
fatty acid composition of dairy ewes.

Journal of Food, Agriculture & Environment, V ol.13 (2), April 2015 77 Materials and Methods
Animals and diets: The experiment was conducted at the
University of Oradea (Romania) during a period of 10 weeks, from
mid-June to August. The first 3 weeks were used for covariate
period (week 1) and adaptation to dietary treatments (weeks 2 and 3). Forty multiparous Turcana ewes (BW = 44.6 ± 1.12 kg) in mid
lactation (60–80 day of lactation and 3 months postpartum) were
divided in 4 homogeneous groups (10 ewes/group), balanced for milk yield, BW, days postpartum, number of lactation and number of lambs born. The four groups were assigned randomly to one of
four dietary groups arranged in a 2 x 2 factorial design. One of the
main treatment factors was the feeding system (indoors during the entire experiment and received 1400 g DM grass hay/d or part-
time grazing – 4 h/day + 700 g DM grass hay/d). All animals received
daily 700 g dry matter (DM) concentrate for lactating sheep, divided into 2 equal halves and given during the morning and
evening milkings. The second main treatment factor consisted of
the supplement type (with and without fat). As source of fat was camelina seed (Cs), which contained 39.6% crude fat and had a high supply of polyunsaturated FA (65.84% of total fatty acids
methyl esters)
9.
The diets of the four ewe groups were as follows: I/-Cs (from
indoors feeding system) with no supplements; I/+Cs (from indoors
feeding system) completed with Cs; PG/ -Cs part-time grazing (4
h/d) with no supplements; PG/+Cs part-time grazing (4 h/d) completed with Cs. Camelina seeds were included in the
concentrate mixture in 20% proportion (Table 1), that is, 140 g/d,
which provided a fat supplement of approximately 55 g/d for the ewes in the corresponding group. The other 2 groups were grazed in the same field, although in separate plots. The ewes had access
to water and vitamin-mineral blocks all the time.
Collection of samples and analytical methods: The ewes were
milked twice daily (07:30, 20:30) and milk yield was recorded every
day. Milk fat, lactose and protein contents were recorded on two
consecutive days each week. Samples from two consecutive milkings were taken on week 6 and week 10 to determine FA profile
of milk fat.
Camelina seed, pasture, hay and concentrate samples were
collected in weeks 3, 5, 7 and 10 of the experiment period (n = 4),
stored at -200C, and used for chemical composition analysis. Feed
samples were analyzed for DM 11, NDF (neutral detergent fiber),
ADF (acid detergent fiber) and ADL (acid detergent lignin) on a Fibersac analyzer (Ankom Technology, Fairport, NY)
12, crude fat and crude protein (CP) 13. Dry matter content of pasture samples
was determined by drying in a freeze drier (Labconco Freeze Dry System). Chemical analysis was expressed on the basis of DM.
Samples (n = 2) of feeds were collected on weeks 6 and 10 for the
determination of FA profile. These samples were immediately
stored at -200C, later lyophilized and ground until analysis. Milk
samples were preserved with 2 tablets of Bronopol®
(BroadSpectrum Micro-tabs II, D&F Control Systems Inc., USA).
The samples were refrigerated at 40C before being analysed for fat
and protein content by infrared analysis (Milk Analyser System
4000, Foss Electric, HillerØd, Denmark). Monohydrate lactose
content was measured on these samples using an enzymatic method
14.
Samples of milk collected on weeks 6 and 10 for FA analysis were frozen at -20
0C without preservatives. To determine FA in
feeds, FA methyl esters (FAME) were prepared by the one-step
extraction-methylation method of Sukhija and Palmquist 15. In order
to determine the composition of fatty acids in milk, the fat was extracted according to the international standard ISO 15884/IDF
182:2002. Fatty acid methyl esters were prepared according to the method proposed by Chouinard et al .
16. FAME were determined
by gas chromatography using a Varian GC 3600 equipped with
FID and a fused silica capillary column (SP 2560 Supelco), 100 m ×
0.25 mm i.d., film thickness 0.20 µm. Helium was used as the carrier
gas at a flow of 1 ml/min. The split ratio was 1:100. The oven
temperature was programmed at 700C and held for 1.50 min, then
increased to 1900C at a rate of 80C/min, held for 25 min, increased
to 2300C at 150C/min, held for 7 min. The temperatures of the injector
and of the detector were set at 2700C. Quantification of FA was
done using 4 mg of heptadecanoic acid as the internal standard
(C17:0; Nu Check Prep Inc., Elysian, MN, USA). A standard FA
mixture containing 50 FA and purified known individual FA were
used to provide standard retention times. FA were indentified by comparing with the retention times of FA in standard samples.
Statistical analysis : Data obtained were analyzed using the
MIXED procedure of SAS 17 for repeated measurements. Fixed
effects were the feeding system, camelina seeds supplementation
and interactions between fixed effects, the time and an appropriate
covariate. Random effect of ewe was used as the error term. Variance-covariance structure was first autoregressive [AR(1)].
For FA proportion in milk fat, analysis was performed without
covariate. Overall differences between treatment means and interaction for feeding systems and camelina seeds were considered to be significant for P<0.05. Trends for significance
were declared at P = 0.05 to 0.10.
Results and Discussion
Chemical composition of treatment feeds : Chemical composition
and FA contents of feeds (camelina seed, pasture, grass hay and concentrate mixture) are presented in Table 2. As expected,
camelina seeds had the highest CP content, while grass hay and pasture had the highest content of cell wall components (NDF
and ADF). All feeds, and the concentrate mixture in particular,
were good sources of linoleic acid (C18:2), but camelina seeds and the pasture were richer in α-linolenic acid (C18:3) (44.12% and
44.58% of the total FAME, respectively).These results were in
accord with those found in the professional literature
5, 7, 9. Though
Camelina sativa L. is a species of the cruciferous family, the linoleic -Cs +Cs
Ingredients concentrate mixed (g/kg)
Maize grain 605 215
Triticale grain 190 410 Soybean meal 155 125 Camelina seed – 200
Minerals and vitamins 50 50
Nutritional value PDIE
1 (g/kg DM) 131.5 130.8
PDIN1 (g/kg DM) 124.2 123.7
NE L2 (kcal/kg DM) 2062 2086
Cs – Camelina seed. 1Calculated values 10. PDIN and PDIE = Digestible CP in the
intestine from microbial protein synthesis when availability of fermentable N in the
rumen is limiting, and from microbial protein synthesis when availability of energy in the rumen is limiting, respectively.
2NEL = Net Energy for lactation 10. Table 1. Ingredients and nutritional values of
concentrate mixture.

78 Journal of Food, Agriculture & Environment, V ol.13 (2), April 2015 acid (C18:2) and the α -linolenic acid (C18:3) contents of its seeds
were similar to those of linseed 7. Additional Cs increased content
of total PUFA, in particular for C18:3, by approximately five times
compared with standard concentrate (14.35 vs. 2.98% of FAME).
Both C18:2 and C18:3 fatty acids serve as precursors of CLA produced by ruminal biohydrogenation
3.
Milk production and composition: The average daily milk yield was higher (p <0.05) for part-time grazing ewes (714.6 – 728.2 ml/d),
than for ewes indoor fed (621.3 – 637.2 ml/d) (Table 3). Milk yield
was not affected by supplementing the diet with Cs. Ewes fed the +Cs diets had higher ECM (energy corrected milk), FPCM [Fat (-
6.5%) and Protein (-5.8%) Corrected Milk], milk fat content and
yield than those fed the -Cs diets.
The effect of oilseed on milk fat content is controversial. In some studies linseed increased the milk fat content in mid-lactating
sheep
18, whereas in others linseed supplementation to early
lactating ewes caused milk fat depression 4, 19. The rate of PUFA
release in rumen is one of the major factors that affects milk fat content. As a result of that, fats with a high ruminal degradability
adversely affect milk fat content, unlike some oleaginous seeds (e.g. flaxseeds) that have low ruminal degradability
20. Therefore,
it can be assumed that the slow release of unsaturated FA from Item Cs Pasture* Grass hay Concentrate mixture
-Cs +Cs
Chemical composition (g/kg of DM2)
Dry matter (DM) 889 210 903 879 881
Crude protein (CP) 270 162 94 189 190 Crude fat 396 32 24 34 95
NDF
3274 519 532 127 173
ADF4169 254 325 34 68
NE L (kcal/kg DM)52584 1380 1016 2040 2091
Fatty acid composition (% of FAME6)
C12:0 0.26 0.45 0.52 0.05 0.05 C14:0 0.19 0.52 0.69 0.14 0.12
C16:0 5.12 17.05 15.18 15.31 13.53 C16:1 0.18 0.14 0.85 0.14 0.12
C18:0 2.47 1.72 6.58 4.21 3.72
C18:1 14.74 3.07 5.62 20.68 17.01 C18:2 n-6 23.06 27.83 24.70 52.27 44.78
C18:3 n-3 44.12 44.58 38.72 2.98 14.35
C20:1 4.17 0.88 1.24 0.52 1.27 C22:1 2.21 0.09 0.43 ND 0.76
SFA
78.04 19.74 22.97 19.71 17.42
MUFA821.30 4.18 8.14 21.34 19.16
PUFA967.18 72.41 63.42 55.25 59.13
Others 3.48 3.67 5.47 3.70 4.29 Table 2. Chemical composition and fatty acid profile of camelina seed (Cs) and feeds consumed
by ewes1.
*Pasture was composed mainly of Festuca rubra , Phleum pratense , Poa pratensis, Trifolium repens. 1Data presented are least square means (n = 4), except
for FA (fatty acid) profile (n = 2 samples per feeds). 2DM = dry matter; 3NDF = Neutral Detergent Fiber; 4ADF = Acid Detergent Fiber; 5The NEL value
was estimated in according INRA 10. 6FAME: fatty acid methyl esters; ND = not detected. 7SFA = saturated FA (C12:0 + C14:0 + C16:0 + C18:0); 8MUFA
= monounsaturated FA (C16:1 + C18:1 + C20:1 + C22:1); 9PUFA = polyunsaturated FA (C18:2 + C18:3)
the Cs in rumen decreased the amount of trans FA and in this way
milk fat depression was avoided 21.
Fatty acid composition in milk fat: The effect of the treatments
on the FA profile of milk fat is presented in Table 4. Dairy ewes fed
indoor (I vs. PG), increased the amount of saturated FA in milk fat
(C10:0, C12:0, C14:0, C16:0) and decreased the monounsaturated (C16:1, t11-C18:1 and c9-C18:1) and polyunsaturated FA (c9,t11-
CLA; t10,c12-CLA; C18:3 n-3; EPA and DHA) contents. For PG
ewes the high milk fat content of ALA, V A and CLA are related to the high content of ALA in green pasture, which is partly biohydrogenated into V A in the rumen and then secreted into milk
and partially converted into c9,t11-CLA in the mammary tissue by
the action of stearoyl-CoA desaturase. Milk fat from PG diet ewes (supplemented or not with Cs) had with over 80% more c9,t11-
CLA isomer than milk fat from the indoor diet ewes. As pasture
intake increased, the milk content of ALA (R
2 = 0.69) and CLA (R2
= 0.79) increased 6. Dhiman et al. 22 reported that cows grazing
pasture had 3 times higher CLA content in milk fat (2.21% of total
FA) compared to cows fed a diet containing 50% conserved forage
(hay and silages) and 50% grain (0.38% of total FA). In dairy sheep are fed on pasture, the concentrations of c9,t11-CLA, V A
and ALA in milk fat were the highest in late winterearly spring,

Journal of Food, Agriculture & Environment, V ol.13 (2), April 2015 79 Feeding system I PG
SEM p values of effects2
Fat supplementation -Cs +Cs -Cs +Cs F Cs F x Cs
Milk yield (g/d) 621.3 637.2 714.6 728.2 26.6 * NS NS
ECM3 (kg/day) 0.587 0.621 0.681 0.724 0.102 ** * NS
FPCM4 (kg/day) 0.638 0.678 0.737 0.786 0.089 ** * NS
Milk fat (%) 6.92 7.77 6.86 7.41 0.110 NS ** NS
Milk protein (%) 5.37 5.21 5.67 5.71 0.073 NS NS NS
Milk lactose (%) 4.83 4.77 4.66 4.73 0.097 NS NS NS Fat yield (g/d) 43.00 47.41 49.02 53.96 1.78 ** ** †
Protein yield (g/d) 33.36 33.20 40.52 41.58 2.11 * NS NS
Lactose yield (g/d) 30.00 30.39 33.30 34.44 0.83 † NS NS Table 3. Production parameters of dairy ewes fed indoor (I) or part-time grazing (PG) diets combined with
(+Cs) or without (-Cs) camelina seed1.
1n = 10 ewes per group. SEM: standard error of mean. 2F: effect of feeding system; Cs: effect of camelina seed; F x Cs: interaction between feeding system and camelina seed.
***: P <0.001, **: P <0.01, *: P <0.05, †: P <0.10, NS: P >0.10. 3Energy Corrected Milk: ECM = Milk Yield (kg/d) x (0.071 x Fat (%) + 0.043 x CP (%) + 0.2224). 4Fat (6.5%)
and Protein (5.8%) Corrected Milk: FPCM (1047 kcal/kg) = Milk Yield, kg x (0.25 + 0.085 x fat,% + 0.035 x protein,%).
when grass availability was the highest, and decreased as lactation
progressed and pasture availability and quality decreased4.
Increases in the concentrations of C18:0, C18:1 cis-9 and trans -11
C18:1 in milk fat and decrease in the concentration of C16:0 were recorded in grazing ewes and cows as compared to those fed indoor
23. The increase of C18:0 concentration in PG diet ewes’
milk fat must have been due to a more complete hydrogenation of
PUFA into C18:0 which probably helped the increase in oleic acid
in milk fat, as this FA is endogenously synthesized in the mammary gland via ∆
9- desaturase of C18:0 24.
If we look at the impact of dietary fat on human health, the
increase in α -linolenic, CLA and oleic acids in milk fat represents
an advantage of pasture-based diets 5. Dietary camelina seed
modified milk fatty acid composition towards a lower level of saturated fatty acids and a higher level of PUFA and MUFA,
confirming how an adequate dietary strategy can improve sheep milk quality. Including Cs in the diet resulted in a significant
increase in both total CLA (c9,t11- CLA and t10,c12-CLA) and
vaccenic acid (t11-C18:1), as well as α-linolenic acid (C18:3 n-3) in
milk fat (p <0.01). Interactions among feeding system and Cs resulted in a significant increase in total CLA, α- linolenic and
oleic acids.
Increase in the C18 FA mainly at the expense of C10 to C16, the response to feeding supplements with camelina seed rich in PUFA,
is determined probably by long-chain FAs that are powerful
inhibitors of de novo lipogenesis in the mammary gland, and this
effect is more marked when FAs have a long chain, are more
unsaturated and contain more trans double bonds
24.
The levels of c9,t11-CLA and t10,c12-CLA in milk fat were higher
when the ewes were fed Cs (p <0.001). Ewes fed +Cs combined
with grazing diet had the lowest proportion of C10:0, C14:0 and
C16:0 (feeding system x Cs: p <0.10 to 0.05) in milk fat; conversely they had the highest proportion of C18:0, t11-C18:1, c9,t11-C18:2,
t10,c12-C18:2, C18:3 n-3, C20:5 n-3 and C22:6 n-3 in milk fat (feeding
system x Cs, p <0.05 to 0.01). The decrease in C12:0, C14:0 and C16:0 resulted in the decrease of milk fat atherogenic index (AI) of PG diet ewes and of those whose diet was supplemented with
camelina seed (+Cs), compared to indoor diet and -Cs diet,
respectively. Conclusions
Feeding part-time grazing to lactating ewes was a useful way to increase CLA isomers and n-3 FA (ALA + EPA + DHA) in milk.
Based on result from the current study, it is suggested that diet
supplementation of camelina seed, to lactating ewes is more effectual way to produce increased potentially healthy fatty acid
profile such as high CLA isomers and ω -3 fatty acid in ewes milk
without any detrimental effects on ewes milk production. This
feeding strategy is particularly useful when the diet of ewes has a poor content and composition of fatty acids, i.e., when stored
forages are used.
Acknowledgements
This work was supported by CNCSIS–UEFISCDI, project number
PN II – IDEI 679/2008.
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Journal of Food, Agriculture & Environment, V ol.13 (2), April 2015 81 I PG
SEM p values of effects2
Fat supplementation -Cs +Cs -Cs +Cs F Cs F x Cs
C4:0-8:0 8.04 7.44 8.74 7.89 0.388 NS NS NS
C10:0 8.96 6.72 6.65 4.21 0.274 * ** *
C12:0 5.45 3.81 3.22 2.07 0.147 ** ** † C14:0 12.34 8.70 8.76 6.67 0.478 *** ** *
C14:1 0.15 0.27 0.13 0.10 0.020 NS NS NS
C15:0 + C17:0 1.15 1.25 1.55 1.15 0.155 NS NS NS C16:0 24.80 22.30 23.19 20.65 1.136 * ** *
C16:1 0.38 0.67 0.52 0.42 0.112 * NS NS
C17:1 0.65 0.45 0.39 0.31 0.022 * † NS
C18:0 9.06 13.12 11.27 14.25 0.478 ** ** †
C18:1 n9t 0.70 0.51 0.59 0.77 0.079 NS NS NS C18:1 trans -11 (VA) 2.15 4.08 3.44 5.72 0.180 ** *** NS
C18:1 n9c 19.04 21.20 22.62 24.80 0.647 *** * NS C18:1 cis-11 0.51 0.69 0.50 0.73 0.051 NS * NS
C18:2 n6t 0.32 0.33 0.31 0.32 0.033 NS NS NS
C18:2 n6c 2.02 2.63 1.87 2.42 0.128 * * *
Total CLA 1.10 2.26 2.09 2.87 0.110 *** ** ** cis-9, trans -11 CLA 1.08 2.22 2.01 2.68 0.155 *** *** **
trans-10, cis-12 CLA 0.02 0.04 0.08 0.19 0.074 *** *** *
C18:3 n-3 (ALA) 1.34 1.70 2.09 2.12 0.122 *** ** *
C20:0 + C24:0 0.48 0.50 0.47 0.53 0.031 NS NS NS
C20:5 n-3 (EPA) 0.21 0.30 0.30 0.43 0.108 * ** NS C22:6 n-3 (DHA) 0.28 0.33 0.37 0.54 0.054 ** ** *
Total n-3 FA 1.83 2.33 2.76 3.09 0.183 *** ** NS
Saturated FA 70.11 63.66 63.67 57.20 0.757 *** *** † Unsaturated FA 29.22 35.60 35.40 41.77 0.563 *** *** NS
Monounsaturated FA 23.58 27.87 28.19 32.85 0.385 *** *** NS
Polyunsaturated FA 5.44 7.73 7.21 8.92 0.284 *** *** ** SCFA (C
4-C10) 17.00 14.16 15.39 12.10 0.212 ** ** †
MCFA (C 12-C17) 44.92 37.45 37.76 31.37 0.258 *** *** †
LCFA (C 18-C22) 37.41 47.65 45.92 55.50 0.586 *** *** NS
HFA342.59 34.81 35.17 29.39 0.609 *** *** †
AI52.72 1.71 1.74 1.18 0.088 *** *** ** Table 4. Fatty acid profile of milk fat from dairy ewes fed indoor (I) or part-time grazing (PG) diets
combined with (+Cs) or without (-Cs) camelina seed1 (% of total FAME).
1n = 10 ewes per group; FAME = fatty acid methyl esters; SEM = standard error of mean; 2F: effect of feeding system; Cs: effect of camelina seed; F x Cs: interaction between
feeding system and camelina seed. ***: P <0.001, **: P <0.01, *: P <0.05, †: P <0.10, NS: P >0.10. VA = vaccenic acid; CLA: conjugated linoleic acid; ALA: α-linolenic
acid; EPA: eicosapentaenoic acid; DHA: docosahexaenoic acid. 3(ALA+EPA+DHA); 4Hypercholesterolaemic fatty acids (C12:0 + C14:0 + C16:0); 5Atherogenicity index
(AI = (C12:0 + (C14:0 x 4) + C16:0 )/UFA); FA = fatty acid; SCFA: short-chain FA; MCFA: medium-chain FA; LCFA: long-chain FA.