EFFECT OF CULTIVATED PASTURE AND INTENSIVE FATTENING ON CARCASS TRAITS AND MEAT QUALITY OF AWASSI LAMBS
A. Ceyhan1*, M. Wilk2, M. U. Asghar2, M. Avcı3, M. U. Hasan1 and M. M. Tanrıkulu4
1Department of Animal Production and Technologies, Faculty of Agricultural Sciences and Technologies, Niğde Ömer Halisdemir University, 51240, Niğde, Turkiye
2Department of Animal Nutrition and Feed Sciences, Wroclaw University of Environmental and Life Sciences, 25 Norwida St., 51-630 Wrocław, Poland
3Department of Plant Production and Technologies, Faculty of Agricultural Sciences and Technologies, Niğde Ömer Halisdemir University, 51240, Niğde, Turkiye; 4Memuta Dairy Farm, Ereğli, Konya, Turkiye
*Corresponding Author’s E-mail: aceyhan@ohu.edu.tr
ABSTRACT
The study aimed to evaluate the carcass trait, meat quality and fatty acid profile of Awassi lambs under cultivated pasture fattening with a concentrated feed (CPF) and intensive fattening (IF) system. A total of 76 male Awassi lambs (36 lambs in the CPF group and 40 in the IF group, 85 days average age) were distributed in complete random design into two experimental groups. The final body weight was lower, but the average daily gain was higher for the lambs on the CPF compared to the lambs on the IF system. There were no significant differences (p>0.05) between CPF and IF system for dressing percentage (50.31 and 51.51%) and shrinkage loss (3.45 and 2.50%), pelvic limb (34.9 and 30.3%), thoracic limb (20.8 and 18.3%), flank (9.4 and 7.6% ), neck (4.4 and 5.9%), and LTL section area (15.6 and 13.0 cm2), except for ribs (25.0 and 33.7%), which were higher in the intensive system. Also, meat pH and color value were not changed by the fattening systems. The fatty acid profile of the longissimus thoracis et lumborum muscles was assessed. The significant differences between groups were noted in margaric (1.00 and 1.80), heptadecenoic (0.51 and 0.99), eicosenoic (80.14 and 0.20), and linolenic fatty acids (0.21 and 0,19). In conclusion, the results of this study imply that carcass traits and meat quality were similar between CPF and IF systems in Awassi male lambs.
Keywords: Awassi lamb, carcass traits, cultivated pasture, fatty acid, intensive fattening, meat quality.
INTRODUCTION
The public generally prefers lamb meat, sheep milk, and dairy products in Turkiye, as in most Mediterranean countries (Gürsoy 2006). According to TURKSTAT (2022), approximately 44 million sheep are kept in Turkiye. The total red meat produced is about 2.191 million tons, of which 26.8% is produced from sheep. The majority of the sheep population are low-productive domestic sheep breeds such as Akkaraman, Morkaraman, Awassi, and Kıvırcık. The Awassi sheep is a popular and widespread breed outside Europe due to their adaptability to tolerate environmental variations and ability to thrive in diverse feeding conditions ranging from steppe to high intensity systems (Ali et al. 2020).
Sheep meat quality is affected by many factors: feed content, feeding system, seasons, slaughter weight, slaughter ages, and breed (Al-Suwaiegh and Al-Shathri 2014, Carneiro et al. 2016, Yalcintan et al. 2017, Khadre and Karabacak 2018, Miguel et al. 2021, Obeidat 2021). Fats serve as the primary energy source for the body and offer valuable nutrients, including essential fatty acids that play a role in cell membrane structure, enhance the flavor of meat, and are crucial for a well-balanced diet when consumed in appropriate proportions (Murariu et al. 2023). The nutritional value of meat depends on the balance between saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA).
However, certain SFAs and trans-MUFAs have been found to have negative effects on blood lipid profiles and are associated with an increased risk of coronary events (Chikwanha et al. 2018). Consequently, consumers of red meat often prefer lamb meat obtained from grazing lambs, considering it to be healthier, more delicious, and more natural compared to meat produced through concentrated feeding systems (Font-i Furnols and Guerrero, 2014).
The Awassi lamb fattening system is based mainly on natural grassland, stubble, and fallow pastures in order to utilize natural resources as much as possible. Pasture-based systems may be a good option for indoor lamb production systems, and to use natural resources and reduce production costs (Ekiz et al. 2013). There is an increasing demand for safe meat production, however, the on-farm cost of feedstuffs is quite high. The EU Common Agricultural Policy is stimulating market interest in pasture production systems (Demirel et al. 2006). Consumers prefer the meat of grazed lambs which is much healthier, tastier, and more natural than meat from concentrate-based production systems (Font-i-Furnols and Guerrero 2014). The concentrate supplementation of grazing lambs enhanced the animal's performance and carcass yield. The feeding system did not affect meat and fat color, fat consistency, or meat proportions (Carrasco et al. 2009).
The effect of cultivated pasture is not well documented in the literature and their comparison of the carcass, meat quality characteristics, and fatty acid content. Therefore, the aim of this study was to investigate the effect of cultivated pasture fattening with concentrated feed consisting of a mixture of wheat grasses, legumes, and an intensive fattening system by evaluating carcass traits, meat quality, and fatty acid content of the longissimus thoracis et lumborum musculus (LTL) of lambs.
MATERIALS AND METHODS
Experimental site:The study was conducted at the Memuta dairy sheep farm, located in the Central Anatolian region of Turkiye at an altitude of 1086 m and at 37∘50′14.2′′ N and 34∘10′39.0′′ E. The long-term average annual precipitation is 329.2 mm, generally distributed in spring and autumn, with a dry summer and some precipitation in the form of snow in winter. The average annual temperature of Konya province is 11.7°C. The highest temperature in July was 40.6°C and the lowest in January was -20.6°C.
Animal care: The study was approved by Niğde Governorate, Provincial Directorate of Agriculture and Forestry of Turkiye (protocol code: E30110456-325.04.02-1061418 and April 2021).
Animal management and experimental design: The lambs remained indoors with ewes for one week and were fed on colostrum and the complement of 1cm3 selenium injected intramuscularly (Yeldif, Ceva, Turkiye; Sodium Selenite -1 mg, Vit E -60 mg, Vit B1 -40 mg per 1ml). After this period, the lambs were kept with the ewes for 40 days. During this period, the ewes were milked, and the lambs were suckled. Two weeks after birth, the lambs were fed with the starter feed and alfalfa hay (Table 1). The nutrient requirements of the lambs were met by feeding a concentrate mix and alfalfa hay according to NRC (2007) guidelines. Chemical analyses were performed according to the procedures described by AOAC (2016). Lambs were subjected to an adaptation period of three weeks according to the feeding systems. During the adaptation period, four lambs from the CPF group were excluded from the experiment due to growth restrictions and health problems.
Table 1. Ingredients and chemical composition of starter feed for Awassi lambs.
Ingredients
|
%
|
Barley
|
15.00
|
Maize
|
25.50
|
Sunflower meal, (CP: 35%)
|
3.70
|
Cottonseed meal, (CP: 26%)
|
6.00
|
Soybean meal, (CP: 44%)
|
43.00
|
Wheat Barn
|
5.00
|
Mineral Premix
|
1.80
|
Chemical composition
|
|
Dry matter
|
90.67
|
Crude protein
|
17.09
|
Crude cellulose
|
5.52
|
Ether extract
|
2.48
|
ADF
|
21.00
|
NDF
|
28.00
|
ME (kcal/kg DM)
|
2747.86
|
CP: crude protein, ADF: acid detergent fiber, NDF: Neutral detergent fiber, ME: metabolizable energy
Cultivated pasture-based grazing fattening (CPF) system: Lambs were grazed in groups on pasture during the day and kept in a semi-open sheepfold at night. The CPF lambs were given concentrate feed (Table 3) at 1.5% of their live weight and had access to fresh water both in the pasture and in the sheepfold. The chemical composition of cultivated pasture is shown in Table 2.
Table 2. The chemical composition of cultivated pasture for Awassi lambs.
Chemical composition
|
%
|
CP grass
|
14.40
|
CP legumes
|
19.02
|
ADF grass
|
32.00
|
ADF legumes
|
35.81
|
NDF grass
|
61.84
|
NDF legumes
|
45.75
|
CP: Crude protein, ADF: acid detergent fiber, NDF: Neutral detergent fiber
Cultivated pasture establishment:An area of 30 hectares was planned for cultivating pasture for sheep. The cultivated pasture was set up with a mixture of six different perennial species of grass: perennial ryegrass (Lolium perenne L.), smooth bromegrass (Bromus inermis), tall fescue (Festuca arundinacea Schreb), and three legume species: white clover (Trifolium repens L.), alfalfa (Medicago sativa L.), and sainfoin (Onobrychis sativa). The NIRS system (FOSS, Denmark) was used to measure the quality of cultivated pasture forage.
Intensive fattening (IF) system: The lambs in the IF group were fed a finisher diet for 56 days. The ingredients and chemical composition of the diet are shown in Table 3.
Table 3. Ingredients and chemical composition of finisher feed for Awassi lambs.
Ingredient
|
%
|
Barley
|
21.70
|
Maize
|
40.40
|
Sunflower meal, (CP: 35%)
|
6.00
|
Cottonseed meal, (CP: 26%)
|
10.00
|
Soybean meal, (CP: 44%)
|
13.00
|
Wheat Barn
|
7.10
|
Mineral Premix
|
1.80
|
Chemical composition
|
|
Dry matter (DM)
|
91.02
|
Crude ash
|
7.20
|
Crude cellulose
|
5.89
|
Ether extract
|
2.83
|
ADF
|
7.70
|
NDF
|
13.70
|
Crude protein
|
15.81
|
ME (Kcal/Kg DM)
|
2815.32
|
CP: Crude protein, ADF: acid detergent fiber, NDF: Neutral detergent fiber, ME: metabolizable energy
Carcass Characteristics and Meat Quality:On the 56th day, the lambs were first starved for 12 hours and then slaughtered according to the Islamic method. During the slaughtering process the live weight, empty body weight (excluding the gastrointestinal tract) and hot carcass, organs (including head, skin, feet, lungs and trachea, liver, heart, spleen, pancreas, gastrointestinal tract, diaphragm, and testicles) were weighted and store 4°C. After 24 h of slaughter, carcasses were weighed again and in order to determine cold carcass weight, dressing percentage sharing losses each carcass. As described by Colomer-Rocher et al. (1987), hot carcasses included kidneys and perinephric-pelvic fat. The dressing percentage and shrinkage loss were calculated according to the presented formulas:


The tail was removed, and the pelvic fat from the two halves was removed and weighed to obtain the contents of the kidney knob and pelvic fat. The chilled carcasses were classified for fatness and conformation using the SEUROP scale as described by (Johansen et al. 2006). Longissimus thoracis et lumborum (LTL) muscle section area and backfat thickness were measured as described by (Boggs et al. 1993).
A pH-meter equipped with a penetrating electrode and a thermometer (Hanna Instruments, HI–9025, Merck, Germany) was used to determine the pH immediately after slaughter carcass dressing (pH30min) and at 24 h post-slaughter (pH24h) pH in the LTL.
Meat color was assessed by lightness (L*), redness (a*), and yellowness (b∗) systems Li et al. (2022) using a colorimeter, the Minolta Chroma Meter CM-700d (Konica Minolta Holdings, Japan). The color was measured on the fresh muscle surface immediately after cutting. Chroma (C*) and hue angle (H*) were calculated with the following formulas Miguel et al. (2021).


Meat fatty acid composition: To determine the fatty acid content, the connective tissue was removed from the meat to avoid contamination by intramuscular and leaking fat. A 150 g portion of the respective muscle tissue was taken. A 10 g sample was vacuum-packed and frozen at -20°C until analysis. Subcutaneous fat samples were obtained from the ribs and the longissimus thoracis et lumborum muscle of each carcass to assess the fatty acid composition. The fatty acid composition of the longissimus thoracis et lumborum muscle was analyzed using gas chromatography (GC). The GC system used in the analysis was equipped with a flame ionization detector (FID) and a capillary column with dimensions of 60 m × 0.25 mm i.d. The capillary column had a film thickness of 0.25 µm and was composed of DB-23, which is a stationary phase made up of 50% cyanopropyl and 50% dimethyl polysiloxane. The injector temperature was set. to 250°C. The oven temperature was programmed as follows: starting at 110°C (held for 6 minutes), increasing to 165°C at a rate of 11°C/min (held for 13 minutes), further increasing to 195°C at a rate of 15°C/min (held for 22 minutes), and finally reaching 230°C at a rate of 7°C/min (held for 7 minutes). Helium was used as the carrier gas at a flow rate of 0-7 ml/min. The injection volume was fixed at 3 µl, and the split ratio was set at 1:50. Each fatty acid methyl ester was reported as a percentage of the total peak area of the chromatogram, excluding the solvent peak. The analyzed fatty acids were further categorized into saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), unsaturated fatty acids (UFA), n-3 PUFA, and n-6 PUFA (Papaloukas et al. 2016).
Nutritional indices: The fatty acid composition of meat was used to calculate an index of healthy fat consumption. The calculation of this ratio was based on the formula by Chen and Liu (2020).

The atherogenicity index (AI) and thrombogenicity index (TI) were calculated according to the formula proposed by Ulbricht and Southgate (1991):


The health-promoting index (HPI) was calculated according to the formula proposed by Chen et al. (2004):

The desirable fatty acid (DFA) index was calculated according to the formula of Rhee et al. (2003):

Statistical analysis: Data was entered into a spreadsheet program, which was used to perform all necessary transformations. Statistical analysis was performed by a General Linear Model univariate with SPSS software package release 22.0 (Watkins 2021). The fattening systems (CPF and IF) as the fixed factors were used. The fattening initial weight was added to the model as covariance. Differences with p≤0.05 were considered as significant (a, b) and p≤0.01 as highly significant (A, B). RESULTS
Carcass characteristics and quality: The initial weight showed a significant difference between the fattening systems but there were no significant differences seen between the birth weight, final weight, and daily live weight gain of Awassi lambs (Table 4).
Table 4. Effect of the fattening system on growth and fattening performance of Awassi lambs.
Growth results (kg)
|
CPF
(n=36)
|
IF
(n=40)
|
SEM
|
p-value
|
Birth Weight, kg
|
4.76
|
4.72
|
0.241
|
0.121
|
Weaning Weight, kg
|
20.64
|
20.62
|
1.820
|
0.943
|
Initial Weight, kg
|
22.96A
|
25.38B
|
1.246
|
0.010
|
Initial age, day
|
85 days
|
85 days
|
Final Weight, kg
|
38.51
|
40.30
|
1.229
|
0.102
|
Final age, day
|
141 days
|
141 days
|
-
|
-
|
Daily Live Weight Gain, kg/d
|
0.278
|
0.267
|
0.008
|
0.290
|
Average Feed intake, kg/d
|
Pasture*
|
1.27
|
SEM: standard error of mean, A,B: significant differences at the level of p≤0.01
* Lambs were fed 1.5% of their live weight in concentrated feed, CPF: Cultivated pasture-based grazing fattening, IF: Intensive fattening.
The proportion of joints obtained from half-left carcasses in Awassi lambs fed in CPF and IF systems are given in Table 5. The differences in terms of ribs were significantly higher in IF than in the CPF group (p≤0.05). No statistical differences were found between the groups in terms of pelvic limb, thoracic limb, flank, neck, dressing percentage, shrinkage loss rates, LTL cross-sectional area, backfat thickness, and SEUROP fat score.
Table 5. The proportion of joints obtained from half-left carcasses in Awassi lambs fattened under an CPF and IF system.
Item, Unite
|
CPF
|
IF
|
SEM
|
p-value
|
Dressing percentage (%)
|
50.31
|
51.54
|
0.782
|
0.471
|
Shrinkage loss (%)
|
3.45
|
2.50
|
0.336
|
0.193
|
Pelvic limb (%)
|
34.9
|
30.6
|
1.26
|
0.980
|
Thoracic limb (%)
|
20.8
|
18.3
|
0.37
|
0.909
|
Flank (%)
|
9.4
|
7.6
|
0.64
|
0.600
|
Neck (%)
|
4.4
|
5.9
|
0.67
|
0.324
|
Ribs (%)
|
25.0a
|
33.7b
|
1.46
|
0.019
|
LTL section area (cm2)
|
15.6
|
13.0
|
1.2
|
0.310
|
Backfat thickness (mm)
|
3.9
|
3.6
|
0.47
|
0.640
|
SEUROP fat conformation
|
2.2
|
2.6
|
0.158
|
0.242
|
SEM: standard error of mean, a,b: significant differences at the level of p≤0.05, CPF: Cultivated pasture-based grazing fattening, IF: Intensive fattening.
The mean values of non-carcass components are given in Table 6. Lambs from the CPF group had a lower head, feet, skin, lungs, trachea, heart, and stomach rate than the IF group. However, the differences were not statistically significant.
Table 6. Non-carcass components of lamb in CPF and IF systems.
Item, Unite
|
CPF
|
IF
|
SEM
|
p-value
|
Head, %
|
6.6
|
6.9
|
0.30
|
0.696
|
Feet, %
|
3.3
|
3.4
|
0.16
|
0.760
|
Skin, %
|
11.5
|
12.0
|
0.58
|
0.666
|
Lungs and trachea, %
|
2.5
|
2.7
|
0.13
|
0.513
|
Liver, %
|
2.4
|
2.4
|
0.06
|
0.733
|
Heart, %
|
0.6
|
0.7
|
0.05
|
0.111
|
Spleen, %
|
0.2
|
0.2
|
0.02
|
1.000
|
Omental and mesenteric fat, %
|
0.8
|
0.8
|
0.05
|
0.583
|
Stomachs, %
|
23.9
|
26.1
|
0.77
|
0.196
|
SEM: standard error of mean, CPF: Cultivated pasture-based grazing fattening, IF: Intensive fattening.
Table 7 shows the LTL of Awassi lambs' colorimetric parameters measured after 24 h slaughter. The lamb fattening system did not affect the pH value of LTL of Awassi lambs after 24 h of cooling at 4℃. The CPF lamb carcass pH value measured at 30 minutes was higher than the IF group. The meat pH value measured after 24 h was found to be lower than the value of the IF group. This affected the result of differences between pH0h - pH24h measurements, which was a statistically significant difference (p≤0.05). Lamb fattening systems did not affect the color characteristics of LTL after slaughter.
Table 7. Values of pH, color characteristics of the LTL of lambs CPF and IF systems.
Item
|
CPF
|
IF
|
SEM
|
p-value
|
pH30min
|
7.4
|
6.9
|
0.10
|
0.064
|
pH24h
|
5.6
|
5.7
|
0.04
|
0.172
|
pH0h - pH24h
|
1.8a
|
1.2b
|
0.09
|
0.020
|
L∗
|
48.2
|
45.7
|
0.88
|
0.192
|
a∗
|
8.7
|
8.0
|
0.45
|
0.211
|
b∗
|
12.1
|
10.8
|
0.55
|
0.617
|
C∗
|
14.8
|
13.5
|
0.62
|
0.337
|
H∗
|
35.1
|
36.3
|
1.06
|
0.596
|
SEM: standard error of mean, a,b: significant differences at the level of p≤0.05, CPF: Cultivated pasture-based grazing fattening, IF: Intensive fattening.
Fatty acid composition and indices: The lamb fattening system influenced the concentration of margaric fatty acid, heptadecenoic fatty acid (p≤0.05), and eicosenoic fatty acid (p≤0.01), which was statistically higher in the IF group. The lamb fattening system also affected the concentration of linolenic fatty acid, which was statistically higher (p≤0.01) in the CPF group. On the other hand, CPF and IF systems did not affect the relation between FA, TI, and AI (Table 8).
Table 8. Effect of the different lamb fattening systems on meat fatty acids profile and relationships between groups of fatty acids, atherogenic index, and thrombogenic index.
Item
|
CPF
|
IF
|
SEM
|
p-value
|
SFA (%)
|
Lauric acid (C12:0)
|
0.72
|
1.61
|
0.319
|
0.215
|
Myristic acid (C14:0)
|
4.51
|
4.35
|
0.387
|
0.841
|
Pentadecanoic acid (C15:0)
|
0.48
|
0.50
|
0.030
|
0.789
|
Palmitic acid (C16:0)
|
30.84
|
29.57
|
0.689
|
0.383
|
Margaric acid (C17:0)
|
1.00a
|
1.80b
|
0.131
|
0.028
|
Stearic acid (C18:0)
|
20.71
|
19.20
|
1.017
|
0.480
|
Arachidic acid (C20:0)
|
0.92
|
1.00
|
0.194
|
0.836
|
MUFA (%)
|
Palmitoleic acid (C16:1)
|
1.47
|
1.65
|
0.204
|
0.661
|
Heptadecenoic acid (C17:1)
|
0.51 a
|
0.99 b
|
0.071
|
0.016
|
Oleic acid (C18:1)
|
36.74
|
38.28
|
1.452
|
0.613
|
Eicosenoic acid (C20:1)
|
0.14 A
|
0.20 B
|
0.000
|
0.001
|
PUFA (%)
|
Linolenic acid (18:3)
|
0.21 A
|
0.19 B
|
0.040
|
0.001
|
Linoleic acid (C18:2)
|
2.07
|
2.80
|
0.302
|
0.260
|
Total FA
|
UFA
|
33.58
|
43.58
|
3.885
|
0.234
|
MUFA
|
31.30
|
40.60
|
3.828
|
0.260
|
PUFA
|
2.28
|
2.98
|
0.299
|
0.272
|
SFA
|
59.12
|
58.02
|
0.726
|
0.146
|
Relations among fatty acids, and thrombogenic and atherogenic indexes
|
h/H
|
0.90
|
1.20
|
0.11
|
0.250
|
AI
|
0.50
|
0.55
|
0.55
|
0.366
|
TI
|
1.35
|
1.21
|
0.061
|
0.121
|
HPI
|
2.09
|
2.34
|
0.34
|
0.376
|
DFA
|
54.28
|
62.78
|
4.02
|
0.580
|
MUFA/SFA
|
0.53
|
0.72
|
0.08
|
0.570
|
PUFA/SFA
|
0.04
|
0.05
|
0.01
|
0.463
|
SEM: standard error of mean, a,b : significant differences at the level of p≤0.05, A,B : significant differences at the level of p≤0.01. CPF: Cultivated pasture-based grazing fattening, IF: Intensive fattening. SFA: Saturated fatty acids, MUFA: Monounsaturated fatty acids, PUFA: polyunsaturated fatty acids.
DISCUSSION
Different sheep breeds and fattening systems influenced the dressing percentages and shrinkage loss (Ekiz et al. 2013, Kocak et al. 2016, Uğurlu et al. 2017). The values of dressing percentages obtained in our study were similar to those reported by Khadre and Karabacak (2018) and Khalaf and Oray (2021) for Awassi lambs.
There were no differences in the rates of the head, feet, skin, lungs, trachea, heart, and stomach between experimental groups. Also, Ekiz et al. (2013) showed no differences among production systems in terms of percentages of the head, feet, heart, empty intestines, and gastrointestinal tract content in Kivircik sheep. Contrary results were reported by Ekiz et al. (2020) for concentrate-based and pasture-based systems in Kivircik sheep, where the production system affected the percentages of non-carcass components of lamb. However, some of the parameters of Ekiz et al. (2020) study are in agreement with our study, which shows the role of cultivated pasture and intensive production systems had a non-significant effect on organ characteristics.
Thoracic limb, ribs, and pelvic limb had higher percentages in all treatments, whereas neck and flank had lower value, these result findings are in agreement with data reported by other authors (Aurousseau et al. 2007, Khadre and Karabacak 2018, Khalaf and Oray 2021). The carcass dressing method and age of slaughter are different in these reports than in our results, which explains the slightly different results. However, Gallo et al. (2019) found that cut proportion was not influenced by the fattening system. Similarly, Kocak et al. (2016) found that the percentages of the neck, shoulder, flank, long leg, tail, and kidneys are not influenced by the production systems. In our study, the LTL area was higher in the CPF group than in the IF system. Moreover, the LTL area from CPF was higher than those obtained by other authors (Esenbuga et al. 2009, Obeidat 2021) from growing Awassi lambs. The differences in the results could be explained by the year effect and the age of the animal.
The pH value of meat is one of the most important criteria used in determining its quality. The increase in lactic acid as a result of the anaerobic glycosides formed in the muscles coupled with the decrease in the oxygen level after slaughter causes the pH value of the meat to be decreased. The pH value of the meat falls between 5.6 and 6.2 in the first half an hour after slaughter. As a result of the decrease in the pH level, the meat becomes more juicy and crunchy. According to Peña et al. (2009) eventual meat pH levels (pH24h) between 5.5 and 5.8 might be classified as a good enough quality range. According to this aspect, the final meat pH levels determined in the current investigation appear to be within permissible limits. The results show that the fattening system did not affect the pH level. The pH value measured after 24 hours was similar to the studies of other authors (Carneiro et al. 2016, Miguel et al. 2021, Obeidat 2021) and was within the range of 5.5 and 5.8 for good quality range meat, regardless of fed system, gender, and seasons of lamb rearing.
Meat color is a significant feature that consumers use to assess the quality and freshness of meat at the moment of purchase (Teke et al. 2018). Pale or pink lamb meat is favored by people in the European Mediterranean regions (Ekiz et al. 2020). Dark meats are usually rejected by consumers, which associate a dark color with old meat or mature animal origin, and therefore with tough flesh (Carneiro et al. 2016). In the presented study, the feeding system had no statistically significant effects on the meat color characteristics. Values of whiteness were higher than those obtained by other authors for Awassi lamb’s longissimus muscles (Khadre and Karabacak 2018, Obeidat 2021). Similarly, Ekiz et al. (2012) reported lower meat lightness characteristics of LTL muscle of lambs kept in different production system ranges. On the other hand, Miguel et al. (2021) evaluated lambs of different slaughter ages and sex got results of meat lightness consistent with ours. Similarly, Yalcintan et al. (2017) reported that the meat's lightness was consistent with ours. The LTL redness value obtained in this study was 8.0 for IF and 8.7 for CPF systems, both values were lower compared to data obtained by other authors (Khadre and Karabacak 2018, Miguel et al. 2021, Obeidat 2021, Yalcintan et al. 2017). In our study, the yellowness value in CPF and IF lambs were 12.1 and 10.8, respectively. Khadre and Karabacak (2018) reported yellowness of Awassi lamb meat around 4.0, Papaloukas et al. (2016) around 5.0, Ekiz et al. (2021) around 2.0-3.0, which is much lower compared to our results. The high yellowness values in the current study could be explained by the amount of fat in the color measurement area. If the measurement area is characterized by a high value of fat, the yellowness will be lower, while high values of yellowness will be recorded due to the lower fat presence (Elizalde et al. 2021). On the other hand, our results present lower values of yellowness compared to those obtained by Obeidat (2021) around 18.0 value.
Costa et al. (2009) reported that the genotype of the animal and provided diet have a significant effect on meat quality. In the presented study, the main constituents of the fatty acid composition were oleic, palmitic, and stearic acids, constituting approximately 70% of the total FA, which is consistent with the FA composition reported by other authors (Flakemore et al. 2017, de Almeida Rego et al. 2017). Similarly, Ekiz et al. (2013) evaluated the effects of different production systems on lamb performance and reported that oleic, palmitic, and staric acids were the most abundant FA in all growing systems. Except for margaric acid, heptadecenoic acid, eicosenoic acid, and linolenic acid, the different lamb fattening strategies showed no significant effect on percentages of particular FA. These findings are consistent with the earlier studies that evaluated the FA composition of lambs fed in pasture-based vs. concentrate-based systems (Ricardo et al. 2015). Oleic acid, recognized for its hypocholesterolemic effect, was the predominant MUFA, which was also observed by Ekiz et al. (2013). Concerning the MUFA detected in the meat fat, oleic acid is the MUFA with the highest expression levels in ruminants. Similarly, Ekiz et al. (2010) observed variations in oleic acid concentration for the LTL muscles of Kivircik lambs in different production systems. However, in the obtained studies, the fattening system did not influence the concentration of oleic acid. Murariu et al. (2023) observed that MUFA ranged between 35.18 - 36.36% in Karagül sheep.
Aurousseau et al. (2007) showed the FA profile of the muscles was more favorable for the lambs raised on grazing. Their fatty acid ratios, CLAs, n-3, n-6 FA, and n-6/n-3 ratio were improved and beneficial for consumption. Moreover, Elizalde et al. (2021) reported that lamb meat from steppe pasture contained higher levels of palmitic, stearic, and oleic acid than lamb meat from the highland. In the present study, the fattening system affected linolenic acid concentration, which was higher in the CPF system. Likewise, Aghwan et al. (2014) observed different levels of C18:3 between treatments with different levels of concentrate, which confirms that linolenic acid amount depends on the type of diet. Interestingly, Elizalde et al. (2021) reported that the C18:3 concentration was much higher in the steppe pasture compared to the highland pasture. This difference may be explained by the wide range of botanical species of grasses on steppe land and high rainfall, which can make grasses greener and more nutritious (Ponnampalam et al. 2012). Al-Suwaiegh and Al-Shathri (2014) and Junkuszew et al. (2020) showed the relationship between the lambs' age and meat linolenic acid concentration. Junkuszew et al. (2020) evaluated ewes and lamb meat and found a significant difference in SFA, MUFA, PUFA, and DFA between treatments. The adult animal meat had a more desirable n-6/n-3 ratio than the lamb meat. These results suggested that the consumption of adult animal meat can be a healthier diet than young lamb meat.
The PUFA/SFA and n-6/n-3 fatty acid ratios are regarded as important indicators for the nutritional assessment of fatty meat (Frunză et al. 2023). Aghwan et al. (2014) reported that a higher PUFA:SFA ratio is important for reducing the risk of cancer and cardiovascular diseases. In the evaluation of meat lipids, the PUFA/SFA ratio holds significant importance, and sheep meat is characterized by a PUFA/SFA ratio ranging from 0.04 to 0.05. Our findings indicated lower values compared to the recommended PUFA/SFA ratio for safe consumption of meat, which should be above 0.4. However, our research revealed higher values compared to other studies conducted by Frunză et al. (2023) (ranging from 1.61 to 186), Lee et al. (2023) on Korean native black goats (ranging from 0.44 to 0.57), and de Carvalho et al. (2022) on Santa Inês crossbred lambs (ranging from 0.12 to 0.15). Costa et al. (2009) reported that PUFA:SFA ratios were influenced by sheep genotypes and diets with different energy concentrations. At the same time, there was a decrease in SFA, atherogenic index (AI) and thrombotic index (TI). These changes in fatty acid composition have a positive effect on meat eaters, as they contribute to a healthier fatty acid profile in meat. Uribe-Martínez et al. (2023) conducted a study to investigate the effects of adding chia seeds (Salvia hispanica L.) to the diet of fattening lamb based on their nutritional requirements. The study aimed to analyze the biometric parameters and fatty acid profiles in the obtained meat. This change in fatty acid composition was statistically significant (p < 0.0001). Zhang et al. (2022) found that a UFA/SFA value of 0.69 for grass finishing and 0.74 for concentrate finishing after grass weaning for Hulunbuir sheep.
To ensure a protective potential for coronary artery health, the AI and TI of atherogenicity and thrombogenicity should be less than 1.0 and 0.5, respectively (Fernandes et al. 2015). Both indexes are used to evaluate the nutritional value of food, based on the lipid fraction levels, which are related to cardiovascular diseases in the human population (Oliveira et al. 2008). Our results are in agreement with Alshamiry et al. (2023) who found that AI values ranged from 0.74, 0.63 and 0.74 and TI values ranged from 1.61, 1.48 and 1.49 in different feeding regimes for Awassi lambs. de Carvalho et al. (2022) reported that AI values of 0.58, 0.57, 0.54 and 0.55 and TI values of 1.43, 1.41, 1.37 and 1.32 for Santa Inês crossbred lambs. Murariu et al. (2023) found that the TI values ranged from 0.78 to 1.22 and the AI values from 0.44 to 0.67 in Karakul sheep. Khaldari et al. (2022) reported that TI value between 1.67-1.72 and AI value between 0.96-0.79 in Lori-Bakhtiari and Romanov crossbred sheep breeds. In this study, it was observed that lamb meat in both groups presented the expected values for AI. However, the TI value was found to be higher than the normal values.
The h/H index considers the functional activity of fatty acids on lipoprotein metabolism responsible for plasma cholesterol transport. It is associated with an increased risk of developing cardiovascular disease, with a higher value indicating a lower risk (Carneiro et al. 2021). This index serves as a tool to assess the cholesterol-lowering effects of lipids, providing information on their impact on cholesterol levels (Murariu et al. 2023). The reference for meat products is the value of 2.0. Products with h/H values above 2.0 mostly consist of hypocholesterolemic FA, thus representing products with a nutritionally desirable FA composition that reduces the risk of cardiovascular disease (Frota et al. 2010). Murariu et al. (2023), reported that the values of h/H range between 2.17 and 2.67 for Karakul sheep and de Carvalho et al. (2022) found that the h:H indices between 1.93, 1.92, 2.00 and 1.97 values for Santa Inês crossbred lambs. The obtained data presents an h/H ratio of around 0.9-1.2, which confirms the results obtained by other authors (Khaldari et al. 2022). Higher h/H values are considered nutritionally beneficial for human health. The type of fattening system did not affect the h/H index. An improvement would be noted if components with a high level of PUFA were added to the diet.
Conclusion: The results of this study imply that carcass traits and meat quality were similar between cultivated pasture-based grazing fattening and intensive fattening systems in Awassi male lambs. The significant difference between fattening methods was noted in margaric, heptadecenoic, eicosenoic, and linolenic fatty acids. However, these differences did not effect on healthy index as the h/H ratio, TI, and AI.
Acknowledgments: This research was supported by the Scientific and Technological Research Council of Turkiye (TÜBİTAK, Project Number: 3190550).
Authors’ Contributions: AC: Conceptualization, Methodology, Software, Writing and Editing; MW: Validation, Writing- Reviewing and Editing; MUA: Investigation, Validation, Writing- Reviewing and Editing; MUA: Reviewing and Editing; MA: Conceptualization, Methodology; MMT: Project administration; MUH: Methodology, Writing. All authors approve the final version of the manuscript.
Conflicts of Interest: The authors declare no conflict of interest.
REFERENCES
- Aghwan, Z.A., A.R. Alimon Y.M. Goh, K. Nakyinsige and A.Q. Sazili (2014). Fatty acid profiles of supraspinatus, longissimus lumborum and semitendinosus muscles and serum in Kacang Goats supplemented with inorganic selenium and iodine. Asian-Australas J. Anim. Sci. 27: 543–550. https://doi.org /5713/ajas.2013.13545
- Ali, W., A. Ceyhan, M. Ali and S. Dilawar (2020). The merits of Awassi sheep and its milk along with major factors affecting its production. J. Agric. Food. Environ. Anim. Sci. 1(1): 50–69.
- Alshamiry, F. A., A. S. Alharthi, H. H. Al-Baadani, R. S Aljumaah and I. A. Alhidary (2023). Growth rates, carcass traits, meat yield, and fatty acid composition in growing lambs under different feeding regimes. Life. 13(2):409. https://doi.org/10.3390/life13020409
- Al-Suwaiegh, S.B and A.A. Al-Shathri (2014). Effect of slaughter age on the fatty acid composition of intramuscular and subcutaneous fat in lamb carcass of Awassi breed. Indian J. Anim. Res. 48: 162–170. https://doi.org/10.3390/life13020409
- AOAC, (2016). Association of Analytical Chemists, Official Methods of Analysis (20th ed.), Latimer Jr., GW, Washington, D.C.
- Aurousseau, B., D. Bauchart, X. Faure, A.L. Galot, S. Prache, D. Micol and A. Priolo (2007). Indoor fattening of lambs raised on pasture. part 1: influence of stall finishing duration on lipid classes and fatty acids in the longissimus thoracis muscle. Meat Sci. 76: 241–252. https://doi.org/10.1016/j.meatsci.2006.11.005
- Boggs D.L and R.A. Merkel (1993). Live animal carcass evaluation and selection manual. IA, Dubuque, Kendall/Hunt Pub. Co: 4th ed, ISBN 978-0-8403-7609-1.
- Carneiro, M.M.Y., R.H. de Tonissi, B. de Goes, B.C.B. Barros, R.T. de Oliveira, A.R.M Fernandes, N.G. da Silva, D.G. Anschau, C.A.L. Cardoso and S.S. Oliveira (2021). Fatty acids profile, atherogenic and thrombogenic health lipid indices in the meat of lambs that received canola grain. Braz. J. Vet. Res. Anim. Sci. 58: e178023–e178023. https://doi.org/10.11606/issn.1678-4456.bjvras.2021.178023
- Carrasco, S., G. Ripoll, A. Sanz, J. Álvarez-Rodríguez, B. Panea, R. Revilla and M. Joy (2009). Effect of feeding system on growth and carcass characteristics of Churra Tensina light lambs. Livest. Sci. 121: 56–63. https://doi.org/10.1016/j.livsci.2008.05.017
- Chen, J., and H. Liu (2020). Nutritional Indices for Assessing Fatty Acids: A Mini-Review. Int. J. Mol. Sci. 21: 5695. https://doi.org/10.3390/ijms21165695
- Chen, S., G. Bobe, S. Zimmerman, E.G. Hammond, C.M. Luhman, T.D. Boylston, A.E. Freeman, and D.C. Beitz (2004). Physical and sensory properties of dairy products from cows with various milk fatty acid compositions. J. Agricul. Food Chem. 52:3422–3428. https://doi.org/10.1021/jf035193z
- Chikwanha, O.C., P. Vahmani, V. Muchenje, E.R. Dugan and C. Mapiye (2018). Nutritional enhancement of sheep meat fatty acid profile for human health and wellbeing. Food Res. Inter. 104, 25–38. https://doi.org/10.1016/j.foodres.2017.05.005
- Colomer-Rocher, F., Morand-Fehr P., Kirton A.H. (1987). Standard methods and procedures for goat carcass evaluation, jointing and tissue separation Livest. Prod. Sci. 17: 149–159. https://doi.org/10.1016/0301-6226(87)90060-1
- Costa, R.G., A.S.M. Batista, P.S., de Azevedo, R.D.C.R. do Egypto, M.S. Madruga and J.T. de Araújo Filho (2009). Lipid profile of lamb meat from different genotypes submitted to diets with different energy levels. Rev. Bras. Zootec. 38: 532–538. https://doi.org/10.1590/S1516-35982009000300019
- de Almeida Rego, F.C., M.C. Françozo, A. Ludovico, F.A.B. de Castro, M, Zundt, C.R. Lupo, L, Belan, L.F.C., Cunha Filho, J.S. dos Santos and C. Castilho (2017). Fatty acid profile and lambs’ meat quality fed with different levels of crude glycerin replacing corn. Semin. Ciênc. Agrár. 38: 2051–2064. https://doi.org/0.5433/1679-0359.2017v38n4p2051
- de Carvalho, A.F., M.J. de Araújo, S.J.A, VallecilloJ, P.C. Neto, A.R. de Souza, L.R. Edvan and L.R. Bezerra (2022). Tissue composition and meat quality of lambs fed diets containing whole-plant sesame silage as a replacement for whole-plant corn silage. Small Rumin. Res. 216: 106799. https://doi.org/10.1016/j.smallrumres.2022.106799
- Demirel, G., H. Ozpinar, B. Nazli and O. Keser (2006). Fatty acids of lamb meat from two breeds fed different forage: concentrate ratio. Meat Sci. 72: 229–235. https://doi.org/1016/j.meatsci.2005.07.006
- Ekiz, B., A. Yilmaz, M. Ozcan and O. Kocak (2012). Effect of production system on carcass measurements and meat quality of Kivircik lambs. Meat Sci. 90: 465–471. https://doi.org/10.1016/j.meatsci.2011.09.008
- Ekiz, B., A. Yilmaz, H. Yalcintan, O. Kocak and M. Ozcan (2020). The effect of final weight on slaughtering and carcass quality characteristics of lambs in concentrate-based or pasture-based production systems. Large Anim. Rev. 26: 67–72.
- Ekiz, B., G. Demirel, A. Yilmaz, M. Ozcan, H. Yalcintan, O. Kocak and A. Altinel (2013). Slaughter characteristics, carcass quality and fatty acid composition of lambs under four different production systems. Small Rumin. Res. 114: 26–34. https://doi.org/10.1016/j.smallrumres.2013.05.011
- Ekiz, B., M. Ozcan, A. Yilmaz, C. Tölü and T. Savaş (2010). Carcass Measurements and meat quality characteristics of dairy suckling kids compared to an indigenous genotype. Meat Sci. 85: 245–249. https://doi.org/10.1016/j.meatsci.2010.01.006
- Ekiz, B., P.D. Kecici, Y.Z. Ograk, H. Yalcintan and A. Yilmaz (2021). Evaluation of the functionality of EUROP carcass classification system in thin-tailed and fat-tailed lambs. Meat Sci. 181: 108603. https://doi.org/10.1016/j.meatsci.2021.108603
- Elizalde, F., C. Hepp, C. Reyes, M. Tapia, R. Lira, R. Morales, F. Sales, A. Catrileo and M. Silva (2021). Growth carcass and meat characteristics of grass-fed lambs weaned from extensive rangeland and grazed on permanent pastures or alfalfa. Animals. 11: 52. https://doi.org/10.3390/ani11010052
- Esenbuga, N., M. Macit, M. Karaoglu, V. Aksakal, M.I. Aksu, M.A. Yoruk and M. Gul (2009). Effect of breed on fattening performance, slaughter and meat quality characteristics of Awassi and Morkaraman lambs. Livest. Sci. 123: 255–260. https://doi.org/10.1016/j.livsci.2008.11.014
- Fernandes, A.P. and V. Gandin (2015). Selenium compounds as therapeutic agents in cancer. Biochem. Biophys. Acta-Gen. Subj. 1850:1642–1660. https://doi.org/10.1016/j.bbagen.2014.10.008
- Flakemore, A.R., B.S. Malau-Aduli, P.D. Nichols and A.E.O. Malau-Aduli (2017). Omega-3 fatty acids, nutrient retention values, and sensory meat eating quality in cooked and raw Australian lamb. Meat Sci. 123: 79–87. https://doi.org/10.1016/j.meatsci.2016.09.006
- Font-i-Furnols, M and L. Guerrero (2014). Consumer preference, behavior and perception about meat and meat products: an overview. Meat Sci. 98: 361–371. https://doi.org/10.1016/j.meatsci.2014.06.025
- Frota, K.D.M.G., A.C.G. Matias and J.A.G. Arêas (2010). Influence of food components on lipid metabolism: scenarios and perspective on the control and prevention of dyslipidemias. Food Sci. Technol. 30: 7-14. https://doi.org/10.1590/S0101-20612010000500002
- Frunză, G., O.C. Murariu, M.M. Ciobanu, M.M. Radu-Rusu, D. Simeanu and P.C. Boișteanu (2023). Meat quality in rabbit (Oryctolagus cuniculus) and hare (Lepus europaeus pallas). A nutritional and technological perspective. Agriculture. 13:126. https://doi.org/10.3390/agriculture13010126
- Gallo, S.B., M.D.B. Arrigoni, A.L.D.S.C. Lemos, M.M.H. Haguiwara and H.V.A. Bezerra (2019). Influence of lamb finishing system on animal performance and meat quality. Acta Sci. Anim. Sci. 41: e44742. https://doi.org/10.4025/actascianimsci.v41i1.44742
- Gursoy, O. (2006). Economics and profitability of sheep and goat production in Turkiye under new support regimes and market conditions. Small Rumin. Res. 62: 181–191. https://doi.org/10.1016/j.smallrumres.2005.08.013
- Johansen, J., A.H. Aastveit, B. Egelandsdal, K. Kvaal and M. Røe (2006). Validation of the EUROP system for lamb classification in Norway; repeatability and accuracy of visual assessment and prediction of lamb carcass composition. Meat Sci. 74: 497–509. https://doi.org/10.1016/j.meatsci.2006.04.017
- Junkuszew, A., P. Nazar, M. Milerski, M. Margetin, P. Brodzki and K. Bazewicz (2020). Chemical composition and fatty acid content in lamb and adult sheep meat. Arch. Anim. Breed. 63:261–268. https://doi.org/10.5194/aab-63-261-2020
- Khadre, A.A.B.A. and A. Karabacak (2018). Comparison of fattening performance and carcass traits measurements of Akkaraman and Awassi male lambs. Selcuk J. Agr. Food Sci. 32: 542–548. https://doi.org/10.15316/SJAFS.2018.135
- Khalaf, F.M. and K.A.D. Oray (2021). Growth performance, carcass characteristics and cost of gain of Awassi and Karadi lambs slaughtered at different weight. J. Duhok. Univ. 24: 134–145. https://doi.org/10.26682/ajuod.2021.24.2.13
- Khaldari, M. and H. Ghiasi (2022). Fatty Acids composition and health indices in different fat and muscle locations of lambs from crossbreeding between Lri-bakhtiari and Romanov sheep breeds. Small Rumin. Res. 216:106786. https://doi.org/10.1016/j.smallrumres.2022.106786
- Kocak, O., E. Bulent, H. Yalcintan and A. Yilmaz (2016). Slaughter and carcass quality characteristics of Chios × Tahirova crossbred lambs under intensive, traditional and organic production systems. Ankara Univ Vet Fak Derg. 63: 187–193. https://doi.org/10.1501/Vetfak_0000002728
- Lee, J., H.J. Kim, S.S. Lee, K.W. Kim, D.K. Kim, S.H Lee and A. Jang (2023). Effects of diet and castration on fatty acid composition and volatile compounds in the meat of Korean native black goats. Anim. Biosci. 36(6): 962. https://doi.org/5713/ab.22.0378
- Li, J., P. Hanselaer and K.A. Smet (2022). Impact of color-matching primaries on observer matching: part I – Accuracy. Leukos. 18: 104–126. https://doi.org/10.1080/15502724.2020.1864395
- Miguel, E., B. Blázquez, and F. Ruiz de Huidobro (2021). Liveweight and sex effects on instrumental meat quality of rubia de el molar autochthonous ovine breed. Animals. 11: 1323. https://doi.org/10.3390/ani11051323
- Murariu, O. C., F., Murariu, G., Frunză, M. M., Ciobanu, and P. C. Boișteanu, (2023). Fatty Acid Indices and the Nutritional Properties of Karakul Sheep Meat. Nutrients, 15(4): 1061. https://doi.org/10.3390/nu15041061
- NRC, (2007). National Research Council. Nutrient Requirements of Small ruminants: Sheep, Goats, Cervids, and New World Camelids (7th ed.), National Academy Press, Washington, DC (2007).
- Obeidat, B.S. (2021). The inclusion of black cumin meal improves the carcass characteristics of growing Awassi lambs. Vet. World. 14: 237–241. https://doi.org/14202/vetworld.2021.237-241
- Oliveira, R.L., M.M. Ladeira, M.A.A.F. Barbosa, D.M.P. Assunção, M. Matsushita, G.T. Santos, and R.L. Oliveira (2008). Ácido linoléico conjugado e perfil de ácidos graxos no músculo e na capa de gordura de novilhos bubalinos alimentados com diferentes fontes de lipídios. Arq. Bras. Med. Vet. Zootec. 60: 169–178. https://doi.org/10.1590/S0102-09352008000100024
- Papaloukas, L., E. Sinapis, G. Arsenos, G. Kyriakou and Z. Basdagianni (2016). Effect of season on fatty acid and terpene profiles of milk from Greek sheep raised under a semi-extensive production system. J. Dairy Res. 83: 375–382. https://doi.org/10.1017/S0022029916000327
- Peña, F., A. Bonvillani, B., Freire, M. Juárez, J. Perea and G. Gómez (2009). Effects of genotype and slaughter weight on the meat quality of criollo cordobes and anglo nubian kids produced under extensive feeding conditions. Meat Sci. 83: 417–422. https://doi.org/10.1016/j.meatsci.2009.06.01
- Ponnampalam, E.N., K.L. Butler, M.B. McDonagh, J.L. Jacobs and D.L Hopkins (2012). Relationship between Muscle Antioxidant Status, Forms of Iron, Polyunsaturated Fatty Acids and Functionality (Retail Colour) of Meat in Lambs. Meat Sci. 90: 297–303. https://doi.org/10.1016/j.meatsci.2011.07.014
- Rhee, K.S., C.J. Lupton, Y.A. Ziprin and K.C. Rhee (2003). Carcass traits of Rambouillet and Merino × Rambouillet lambs and fatty acid profiles of muscle and subcutaneous adipose tissues as affected by new sheep production system. Meat Sci. 65: 693–699. https://doi.org/10.1016/S0309-1740(02)00290-5
- Ricardo, H.A., A.R.M. Fernandes, L.C.N. Mendes, M.A.G. Oliveira, V.M. Protes, E.M. Scatena, R.O. Roça, N.B. Athayde, L.V.C Girão, and L.G.C. Alves (2015). Carcass traits and meat quality differences between a traditional and an intensive production model of market lambs in Brazil: Preliminary investigation. Small Rumin. Res. 130: 141–145. https://doi.org/10.1016/j.smallrumres.2015.07.007
- Teke, B., B. Ekız, F. Akdag, M. Ugurlu and G. Cıftcı, (2018). Effect of lairage time after short distance transport on some biochemical stress parameters and meat quality of Karayaka lambs. Large. Anim. Rev. 24: 41–44.
- TURKSTAT, 2022. Turkish Statistical Institute, Agricultural Statistics, Livestock Statistics. Red Meat Production Statistics. https://data.tuik.gov.tr/Bulten/Index?p=Red-Meat-Production-Statistics-2022-49696. Accessed 7 July 2023.
- Ugurlu, M., B. Ekiz, B. Teke, M. Salman, F. Akdağ and I. Kaya (2017). Meat quality traits of male Herik lambs raised under an intensive fattening system. Turk. J. Vet. Anim. Sci. 41: 425–430. https://doi.org/10.3906/vet-1701-79
- Ulbricht, T.L.V., and D.A.T. Southgate (1991). Coronary Heart Disease: Seven Dietary Factors. The Lancet 338: 985–992. https://doi.org/10.1016/0140-6736(91)91846-M
- Uribe-Martínez, S., J.A. Rendón-Huerta, V.G. Hernández-Briones, A. Grajales-Lagunes, J.Á. Morales-Rueda, G. Álvarez-Fuentes and J.C. García-López (2023). Effects of chia seeds on growth performance, carcass traits and fatty acid profile of lamb meat. Animals.13(6), 1005. https://doi.org/10.3390/ani13061005
- Watkins, M.W. (2021). A Step-by-Step Guide to Exploratory Factor Analysis with SPSS; 1st Edition, New Yor. https://doi.org/10.4324/9781003149347 .
- Yalcintan, H., B. Ekiz, O. Kocak, N. Dogan, P.D. Akin and A. Yilmaz (2017). Carcass and meat quality characteristics of lambs reared in different seasons. Arch. Anim. Breed. 60: 225–233. https://doi.org/10.5194/aab-60-225-2017
- Zhang, Z., X. Wang, Y. Jin, K. Zhao and Z. Duan (2022). Comparison and analysis on sheep meat quality and flavor under pasture-based fattening contrast to intensive pasture-based feeding system. Anim. Biosci. 35(7):1069. https://doi.org/5713/ab.21.0396
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