Meat Quality Characteristics of Male Atak-S Layer Chicks Reared Under Different Housing Systems

ABSTRACT

This study aimed to evaluate the effects of closed rearing and free-range systems on meat quality characteristics and fatty acid composition of male Atak-S layer chicks culled at one day of age, and to determine the potential use of this genotype in different production systems. A total of 168 Atak-S male chicks were reared under identical conditions up to 21 days of age, and then randomly allocated either of two groups, closed rearing system (CRS) and free-range system (FRS), with three replicates of 28 birds per treatment. The trial continued until 12 weeks of age. After slaughter, physicochemical quality analyses, color measurements, cholesterol determination, and fatty acid profile analyses were conducted on breast and thigh meat samples. The rearing system had no significant effect on pH, moisture content, water-holding capacity, or color characteristics of either breast or thigh meat (p>0.05). In breast meat, protein content was higher in the free-range group, while cholesterol content was higher in the closed system group (p<0.05 and p<0.01, respectively), whereas fat content was not affected by the rearing system (p>0.05). In thigh meat, ΣMUFA content and oleic acid levels were significantly influenced by the rearing system (p<0.05), whereas ΣSFA, ΣPUFA, and most individual fatty acids were not affected. In breast meat, the ΣPUFA: ΣSFA ratio and heptadecanoic acid content showed significant differences between housing systems (p<0.05). The findings indicate that Atak-S male chickens may represent a potential genetic resource for free-range and alternative production systems.

Keywords:
Atak-S; layer male chicks; housing systems; meat quality; fatty acid composition

INTRODUCTION

In broiler production, fast-growing broiler genotypes are predominantly used; however, consumer demand is steadily increasing for products perceived as healthier and more sustainable (Nabilasari et al., 2025). This demand has accelerated the significant expansion of organic poultry production, which has become a niche market within the sector (Eleroğlu et al., 2013). In response to this growing demand, organic production models have been developed, mostly based on slow-growing broiler lines requiring a rearing period of at least 81 days.

The growth rate of a broiler genotype is considered a critical factor affecting animal welfare (Dixon, 2020; Baxter et al., 2021; Tainika et al., 2023). Breeding programs aimed at accelerating growth have led to increases in live weight by approximately 400% and breast meat yield by approximately 80% (Emambu et al., 2023; Nabilasari et al., 2025). However, this selection process has also brought about various welfare issues in fast-growing lines, such as locomotor disorders, cardiovascular problems, and behavioral deficiencies (Nicol et al., 2024). As a result of these developments, global demand for free-range poultry meat products is increasing, both due to concerns about animal welfare and the perception that these products are of higher quality.

The culling of day-old chicks of male layers in egg production leads to serious ethical and economic problems (Krautwald-Junghanns et al., 2018; de Haas et al., 2021). This practice has raised significant animal welfare debates, particularly in the European Union, and has encouraged the exploration of viable alternatives (Krautwald-Junghanns et al., 2018). Key alternative strategies include in-ovo sex determination methods (Krautwald-Junghanns et al., 2018), breeding dual-purpose genotypes developed for both meat and egg production (Torres et al., 2019; Baldinger & Bussemas, 2021), and utilizing male layers from egg-type lines in processed meat products (Murawska et al., 2019). However, male chicks obtained from laying hen lines selected solely for egg production generally have very low meat yields, limiting their competitive use in conventional meat production systems.

In broilers, animal welfare is significantly affected by whether the genotype has a slow or fast-growing structure (Dixon, 2020; Baxter et al., 2021; Tainika et al., 2023). The quality characteristics of poultry meat are determined by the combined effect of genetic structure, rearing system, and growth period (Eleroğlu et al., 2013). Both genotype and housing conditions can lead to differences in the characteristics of broiler meat (Özbek et al., 2020). Increased physical activity in free-range systems stands out as one of the factors that can alter meat quality (Martínez-Pérez et al., 2017). In this context, the free-range system is considered a potential alternative production method that can affect specific meat quality characteristics (El-Deek et al., 2019).

This study aimed to reduce the culling of the egg-type male chicks at day-old age. To this end, it evaluates the feasibility of rearing Atak-S laying male chicks in both closed and free-range systems. The research also examined the effects of these different rearing environments on meat quality parameters and analyzed the usability of these birds in slow-growing broiler production.

MATERIALS AND METHODS

Experimental Setup and Housing

The study was conducted in a tent-type poultry house at the Animal Production Application and Research Center of Kahramanmaraş Sütçü İmam University (KSU), with the approval of the KSU Faculty of Agriculture Animal Experiments Local Ethics Committee (Approval No. 2019/07). The facility measured 25 m in length and 7 m in width, with side walls 2 m high and a central ridge height of 3.8 m. The greenhouse-type structure was covered with a triple layer consisting of an outer white 1100 denier tarpaulin, a middle layer of air foam insulation, and an inner lining of thin tarpaulin. Internally, the house was divided lengthwise into two equal sections by a 1 m wide service corridor. In the closed housing system (CRS), birds were kept in three enclosed compartments that together provided 7.5 m² (3 m × 2.5 m) per replicate. For the free-range system (FRS), the same indoor area was supplemented with an outdoor area of 31.25 m² (2.5 m × 12.5 m) per replicate.

Animal Management and Husbandry

A total of 168 day-old male chicks of the Atak-S layer genotype (a slow-growing, low-meat-yield line) were used. During the first three weeks, all chicks were reared together under identical conditions. On day 21, the chicks were randomly allocated either one of two housing treatments (CRS and FRS), each comprising three replicates of 28 birds (84 birds per treatment). The trial lasted 12 weeks (27 June - 19 September). Stocking density was set at 3.73 birds/m² indoors and 0.90 birds/m² in the outdoor area, which had been sown with clover to establish vegetative cover. The building was naturally ventilated via twenty windows (45 × 75 cm) and four ventilation shafts (40 × 40 cm, 60 cm high). Large access doors (2 × 2.5 m) were placed at both ends of the house; smaller doors (45 × 75 cm) allowed birds in the FRS group to enter the outdoor area.

Feeding and Watering

All birds were fed the same phase diets ad libitum (Table 1). During the first three weeks, feed was offered in chick feeders (50 × 70 cm) and water in chick drinkers. From week 4 onward, each replicate was provided with a tube feeder and a nipple drinker line equipped with ten nipples. Feed consumption was recorded collectively for the first three weeks and separately per replicate thereafter. Pine wood shavings (4-5 cm deep) were used as bedding. A lighting schedule of 23 h light: 1 h dark (23L:1D) was maintained throughout the experiment. Supplementary heat was supplied during the first two weeks using thermostatically controlled electric heaters. Vaccinations were administered via drinking water as follows: Newcastle disease (B1 strain) on day 11, Gumboro disease (D78 strain) on days 13 and 22, and Newcastle disease (LaSota strain) on day 30. Birds in the FRS group were allowed access to the outdoor area from the fourth week.

Table 1
Feed types provided to chicks at different ages

Ingredients, %	0-21 days	22-35 days	36-84 days
Metabolizable energy, kcal/kg	12.20	12.56	13.08
Crude Protein, %	22.00	20.50	19.50

Slaughter and Sampling

On day 84, after a 12-hour feed withdrawal (water available ad libitum), all birds were individually weighed. For meat quality analyses, three birds per replicate (18 birds in total: 2 housing systems × 3 replicates × 3 birds) were randomly selected. Following a 12-hour fast (water available), these birds were slaughtered without stunning in accordance with Turkish slaughter regulations and with approval from the institutional ethics committee (protocol 2019/07). Slaughter was performed manually at a local organic processing facility by severing the throat and major cervical blood vessels. Carcasses were scalded at 54 °C for 30 s, mechanically defeathered, and then immersed in 22 °C water for 20 min to promote partial cooling and reduce bacterial load. Evisceration was carried out through an abdominal incision. Carcasses were subsequently chilled at +4 °C for 24 h before dissection.

Meat Quality Measurements

After chilling, breast and thigh muscles were excised, minced, and subjected to the following analyses.

Ash Determination

Ash content was determined gravimetrically. Crucibles were heated in a muffle furnace (Protherm PLF 120/7, Ankara) at 550 °C for about 1 h to achieve constant weight. A 3 g sample was then weighed into the crucible, subjected to gradual precombustion, and ashed at 550 °C until a white residue was obtained. Ash percentage was calculated as:

$Ash(\%)=\frac{\left(M_r-M_c\right)}{m\times 100}$ (1)

M_r: Mass of crucible with ash, (g)

M_c: Mass of empty crucible (g)

m: mass of the sample (g)

Moisture Determination

Approximately 5 g of sample was weighed into a predried, tared container. The sample was dried in an oven at 105 °C for 4 h, cooled in a desiccator, returned to the oven for an additional hour to confirm constant weight, and recooled. Moisture content was calculated according to Yetim et al. (2012).

$Moisture(\%)=\frac{\left(M_1-M_0\right)}{m\times 100}$ (2)

M₀: Tare weight of the drying container (g)

M₁: Weight of the sample after drying, including the container (g)

m: Weight of the sample (g)

Water-Holding Capacity (WHC)

WHC was assessed following the procedure of Hughes et al. (1997). A 10 g sample was heated in a water bath at 90 °C for 10 min, cooled, wrapped in cotton gauze, and centrifuged at 1400 rpm for 15 min. After centrifugation, the gauze was removed and weighed. WHC was calculated as:

$WHC(\%)=(1–T_1/M_1)\times 100=(1-(B_1–A_1)/M_1)\times 100$ (3)

T₁: The total amount of water lost after the heating and centrifugation process (g)

B₁: Sample weight before heating (g)

A₁: Sample weight after heating and centrifugation (g)

M₁: Total water in the sample (g)

Protein Determination

Protein content was determined using a Kjeltec nitrogen analyzer based on the Kjeldahl method. Nitrogen percentage was obtained as:

$Nitrogen(N,\%)=\frac{\left(V_1-V_0\right)\times 0.0014\times N}{m(g)}\times 100$ (4)

V₁: Volume of 0.1 N HCl consumed during titration of the sample (mL)

V₀: Volume of 0.1 N HCl consumed in the blank titration (mL)

N: Normality of the 0.1 N HCl solution used in the titration

m: Weight of the sample (g)

Crude protein was calculated by multiplying the nitrogen percentage by 6.38 (Yetim et al., 2012):

$\mathrm{Pr}otein(\%)=Nitrogen(\%)\times 6.38$ (5)

Fat Content

Fat content was analyzed according to TS EN ISO 11085 using the Randall extraction method, with an automatic Soxhlet extractor. After filtration and dehydration of the extracted oil, the fat percentage was determined gravimetrically (Hosseini et al., 2019):

$Oil(\%)=Msy/Mo\times 100$ (6)

Msy: weight of extracted fat (g)

Mo: weight of sample (g)

Cholesterol Determination

For cholesterol analysis, samples were homogenized, dissolved in alcohol, filtered, and subjected to a water bath treatment followed by centrifugation. The resulting supernatant was incubated with an enzymatic cholesterol assay kit (Boehringer Mannheim GmbH Biochemica, 1995) at 37 °C for 10 min, and the absorbance was measured at 520 nm using a spectrophotometer.

Fatty Acid Profiles

Fatty acid profiles were determined after methylation using a Shimadzu Gas Chromatography system (Model 2025) equipped with a flame ionization detector (FID). The Supelco 37 Component Mix (Supelco Company) was used as the certified standard. Gas flow conditions were set at H₂ = 40 mL/min and dry air = 400 mL/min (Eser et al., 2020).

Color Characteristics

Color characteristics were analyzed using a HunterLab Color Flex spectrophotometer under standardized D65 daylight conditions and a 10° viewing angle. L* (lightness), a* (redness/greenness), and b* (yellowness/blueness) values were determined based on the CIE Lab* color space system. Color difference (ΔE*) was calculated as ΔE* = √(L² + a² + b²), chroma (C*) as C* = √(a² + b²), and hue angle (H°) as H° = tan^-1(b*/a*).

Statistical Analysis

Data were analyzed using a randomized design with three replications. The effects of housing systems on the evaluated traits were assessed by analysis of variance (ANOVA), and treatment differences were tested using the F-test. Statistical significance was determined based on p-values according to the procedures described by Bek & Efe (1987). All statistical analyses were performed using IBM SPSS Statistics Version 22.0 (IBM Corp., Armonk, NY, USA).

RESULTS AND DISCUSSION

The results of meat quality analyses for Atak-S males reared under different housing systems, including pH, raw ash, moisture, water-holding capacity (WHC), protein, fat, cholesterol content, color parameters (L*, a*, b*, H°, C*, and ΔE), and fatty acid composition (ΣSFA, ΣMUFA, ΣPUFA, P:S ratio, and individual fatty acids) are summarized in Tables 2-8.

Table 2
pH, raw ash, moisture, and water-holding capacity (WHC) analysis results of CP of Atak-S roosters.

Carcass Part (CP)	Characteristics	FRS±SEM	CRS±SEM	F	p-value
Thigh	pH	5.22±0.17	4.99±0.10	0.807	0.382
	Raw ash (%)	1.00±0.01	1.05±0.01	6.330	0.023
	Moisture (%)	73.3±0.23	72.31±0.46	2.099	0.167
	WHC (%)	24.93±0.17	24.88±0.31	0.012	0.912
Breast	pH	4.65±0.07	4.53±0.07	0.974	0.338
	Raw ash (%)	1.11±0.01	1.11±0	0.313	0.584
	Moisture (%)	71.52±0.18	71.78±0.16	0.669	0.426
	WHC (%)	25.78±0.14	25.44±0.16	1.397	0.255

• FRS: Free range system, CRS: Closed housing system, CP: Carcass Part, WHC: Water Holding Capacity.

Table 3
Protein, fat, and cholesterol analysis results of CP of Atak-S roosters.

Carcass Part (CP)	Characteristics	FRS±SEM	CRS±SEM	F	p-value
Thigh	Protein (%)	20.61±0.27	18.96±0.63	3.181	0.093
	Fat (%)	14.03±0.29	14.39±0.78	0.103	0.752
	Cholesterol	66.62±3.22	74.25±4.84	0.967	0.340
Breast	Protein (%)	24.67±0.22	21.85±0.92	5.010	0.040
	Fat (%)	4.11±0.2	3.98±0.2	0.138	0.715
	Cholesterol	47.93±0.54	66.06±2.56	26.993	0.000

• FRS: Free range system, CRS: Closed housing system, CP: Carcass Part.

Table 4
Color L*, a*, b*, hue, chroma, and ΔE analysis results of CP of Atak-S roosters.

CP	Characteristics	FRS±SEM	CRS±SEM	F	p-value
Thigh	Color L*	53.55±1.27	51.41±0.86	1.099	0.310
	Color a*	6.44±0.56	5.95±0.43	0.277	0.606
	Color b*	12.32±1	12.11±0.77	0.015	0.903
	H°	62.38±1.21	63.66±1.4	0.270	0.610
	C*	13.95±1.11	13.54±0.84	0.048	0.829
	ΔE	55.57±1.03	53.3±0.67	1.907	0.186
Breast	Color L*	55.48±0.97	54.25±0.99	0.445	0.514
	Color a*	5.01±0.35	5.37±0.22	0.408	0.532
	Color b*	16.52±0.52	16.05±0.23	0.373	0.550
	H°	73.17±1.01	71.52±0.72	0.993	0.334
	C*	17.3±0.55	16.94±0.24	0.195	0.664
	ΔE	58.16±0.92	56.85±0.96	0.549	0.469

• HS: Housing System, FRS: Free range system, CRS: Closed housing system, CP: Carcass Part.

Table 5
Fatty acid composition.

CP	Characteristics	FRS±SEM	CRS±SEM	F	p-value
Thigh	ΣSFA	31.77±0.22	31.08±0.24	2.502	0.133
	ΣMUFA	32.68±0.32	34.94±0.66	5.397	0.034
	ΣPUFA	35.56±0.47	33.87±0.77	1.969	0.180
	P/S	1.12±0.02	1.09±0.03	0.322	0.578
Breast	ΣSFA	33.89±0.21	33.3±0.21	2.210	0.157
	ΣMUFA	34.58±0.7	33.62±0.42	0.776	0.391
	ΣPUFA	31.53±0.56	32.96±0.43	2.323	0.147
	P/S	0.93±0.01	0.99±0.02	4.665	0.046

• HS: Housing System; FRS: Free range system; CRS: Closed housing system; CP: Carcass Part, ΣSFA: Total saturated fatty acids; ΣMUFA: Total mono-unsaturated fatty acids; ΣPUFA: Total polyunsaturated fatty acids; P/S: ΣPUFA to ΣSFA ratio.

Table 6
Saturated fatty acid analysis results of CP of Atak-S roosters.

CP	ΣSFAs	FRS±SEM	CRS±SEM	F	p-value
Thigh	Lauric acid	0.14±0	0.14±0	0.616	0.444
	Myristic acid	0.63±0.01	0.65±0.02	1.014	0.329
	Palmitic acid	20.32±0.26	20.48±0.36	0.077	0.785
	Heptadecanoic acid	0.19±0.01	0.18±0.01	0.472	0.502
	Stearic acid	8.34±0.12	7.85±0.14	3.883	0.066
	Heneicosanoic acid	0.28±0.01	0.27±0.02	0.184	0.674
	Behenic acid	1.46±0.11	1.15±0.13	1.892	0.188
	Tricosanoic acid	0±0	0±0	-	-
	Lignoceric acid	0.41±0.03	0.35±0.03	1.559	0.230
Breast	Lauric acid	0.14±0	0.15±0	0.489	0.495
	Myristic acid	0.62±0.01	0.66±0.02	1.461	0.244
	Palmitic acid	21.83±0.22	21.14±0.2	2.981	0.103
	Heptadecanoic acid	0.15±0	0.18±0	18.545	0.001
	Stearic acid	8.34±0.17	8.56±0.09	0.749	0.399
	Heneicosanoic acid	0.24±0.01	0.26±0.02	1.177	0.294
	Behenic acid	2.06±0.14	1.85±0.17	0.513	0.484
	Tricosanoic acid	0±0	0±0	-	-
	Lignoceric acid	0.5±0.04	0.5±0.03	0.000	0.986

• FRS: Free range system, CRS: Closed housing system, CP: Carcass Part, ΣSFAs: saturated fatty acids.

Table 7
Mono-unsaturated fatty acid analysis results of CP of Atak-S roosters.

CP	ΣMUFAs	FRS±SEM	CRS±SEM	F	p-value
Thigh	Pentadecenoic acid	0.05±0.01	0.05±0.01	0.101	0.755
	Myristoleic acid	0.05±0.01	0.04±0.01	0.006	0.937
	Palmitoleic acid	2.14±0.09	2.62±0.2	2.733	0.118
	Oleic acid	30.25±0.24	32.08±0.51	6.002	0.026
	Nervonic acid	0.2±0.02	0.15±0.02	1.714	0.209
Breast	Pentadecenoic acid	0.01±0.01	0.00±0.00	1.000	0.332
	Myristoleic acid	0.08±0.01	0.07±0.01	0.344	0.566
	Palmitoleic acid	2.63±0.21	2.14±0.12	2.318	0.147
	Oleic acid	31.6±0.51	31.18±0.33	0.268	0.612
	Nervonic acid	0.26±0.02	0.23±0.01	1.177	0.294

• FRS: Free range system; CRS: Closed housing system; CP: Carcass part; ΣMUFA: mono-unsaturated fatty acids.

Table 8
Polyunsaturated fatty acids analysis results of CP of Atak-S roosters.

CP	ΣPUFAs	FRS±SEM	CRS±SEM	F	p-value
Thigh	Linoleic acid	33.65±0.45	32.15±0.73	1.716	0.209
	Gamma-linolenic acid	1.35±0.03	1.19±0.04	7.301	0.016
	Alpha-linolenic acid	0.26±0.01	0.27±0.01	0.549	0.469
	Eicosatrienoic acid	0.17±0.01	0.15±0.01	1.864	0.191
	Docosahexaenoic acid	0.13±0.01	0.11±0.01	1.772	0.202
	Eicosapentaenoic acid	0±0	0±0	-	-
Breast	Linoleic acid	29.68±0.5	31.16±0.41	2.940	0.106
	Gamma-linolenic acid	1.19±0.04	1.2±0.02	0.0000	0.990
	Alpha-linolenic acid	0.26±0.01	0.24±0.01	1.108	0.308
	Eicosatrienoic acid	0.2±0.01	0.19±0.01	0.123	0.730
	Docosahexaenoic acid	0.2±0.02	0.18±0.01	1.326	0.266
	Eicosapentaenoic acid	0±0	0±0	-	-

• FRS: Free range system, CRS: Closed housing system, CP: Carcass part, ΣPUFAs: Polyunsaturated fatty acids.

According to Table 2, the effect of the housing system (HS) on raw ash value was statistically significant (p<0.05) in thigh meat but insignificant in breast meat (p>0.05). The differences between the pH, moisture and WHC values of thigh and breast meats were not significant (p>0.05). No significant influence of housing systems was observed on the pH values of thigh and breast meat. The mean pH values of thigh meat were 5.22 and 4.99 for FRS and CRS, respectively, while the mean pH values of breast meat were 4.65 and 4.53, respectively. There were no differences in raw ash content among the treatments in breast meat; however, raw ash values of thigh meat were statistically different (p<0.05). In this study, raw ash values of thigh meat were 1.00% and 1.05% for FRS and CRS, respectively, whereas both breast meat groups showed a raw ash value of 1.11%. Housing systems had no significant effect on the moisture content of CP (p>0.05). The moisture values of thigh meat were 73.30% and 72.31% for FRS and CRS, respectively, while the moisture values of breast meat were 71.52% and 71.78%, respectively. Housing systems had no significant effect on the water-holding capacity (WHC) of CP (p>0.05). In the present study, the WHC values of thigh meat were 24.93% and 24.88% for FRS and CRS, respectively, while the WHC values of breast meat were 25.78% and 25.44%, respectively.

The pH values of thigh and breast meat were not significantly influenced by housing system in this study. The pH values of thigh meat were 5.22 and 4.99 for FRS and CRS, respectively, whereas the pH values of breast meat were 4.65 and 4.53, respectively. Previous studies have indicated that meat pH values depend on chicken genotype and muscle type (Choe et al., 2020), with thigh muscles typically exhibiting higher pH values than breast muscles (Sampaio et al., 2012), findings that are in agreement with the present study. In contrast, Semwogerere et al. (2018) reported considerably higher average pH values for thigh (6.32) and breast meat (6.17) compared to those observed here. A low pH is frequently associated with reduced water-holding capacity. While Eleroğlu et al. (2013) reported water-holding capacity values between 66.08% and 71.46%, this study found considerably lower values ranging from 24.88% to 25.78%. These findings support the relationship between reduced water-holding capacity and low pH values.

The thigh meat raw ash values obtained in this study were 1.00% and 1.05% for FRS and CRS, respectively, and the difference between housing systems was statistically significant (p<0.05). In contrast, breast meat raw ash values were both determined as 1.11%, with no significant effect of housing system. The breast meat raw ash values obtained in this study were lower than those reported by Bostami et al. (2017), where raw ash content in chicken breast meat varied between 1.42% and 1.51%. The absence of significant differences in breast meat raw ash content between housing systems in the present study is consistent with the reports of Da Silva et al. (2017) and Özbek et al. (2023), who reported that raw ash levels in broiler breast meat were not affected by free-range and conventional systems. As reported by Olaifa et al. (2016) and Özbek et al. (2023), differences in meat raw ash content may arise due to housing conditions and genotype, which can cause variations in broiler meat quality. Çapan et al. (2021) reported that the mean ash content of thigh meat was 1.06% and 1.18% in organic and conventional housing systems, respectively, whereas the corresponding values for breast meat were 1.20% and 1.28%. These findings support the results of the present study regarding raw ash levels, indicating that housing systems may cause variations in ash content depending on production conditions. In another study on the effects of housing systems on the meat quality characteristics of spent laying hens (Semwogerere et al., 2018), the thigh and breast meat raw ash values obtained in free-range and caged housing systems were 1.0-2.0% and 1.1-1.3%, respectively. These findings are consistent with the present research, in which the same values were 1.00-1.05% and 1.11%, respectively, and can be explained by the similar genotype and breeding aspects of layers used in both studies.

In this study, slight numerical variations in moisture content and water-holding capacity were observed in thigh and breast meat between housing systems. However, previous reports have indicated that housing system does not influence the moisture content of thigh and breast meat obtained from organic and conventional production, with average moisture values ranging from 72.62% to 76.42% (Çapan et al., 2021). In the same study, the average moisture contents of CP were 74.59% and 73.98%, respectively. In the present study, no effect of the housing systems was found on the moisture contents of CP, but the moisture values of thigh and breast meat were 73.30% and 72.31% in thigh meat and 71.52% and 71.78% in breast meat for FRS and CRS, respectively. It has been reported that the moisture content of breast meat in different chicken breeds ranges from 74.42% to 74.93%, while that of thigh meat ranges from 74.46% to 76.62% (Chen et al., 2016). Another study found that the moisture content of breast meat from free-range chickens was 74.5%, higher than that of breast meat from caged chickens at 73.9% (Semwogerere et al., 2018). The moisture contents of thigh and breast meats are within the ranges reported in the literature (Chen et al., 2016; Semwogerere et al., 2018; Çapan et al., 2021). Housing systems and feeding techniques applied may cause some differences. Given that over 100 methods have been described in the literature for measuring WHC (Barbut, 2024), direct comparisons of absolute values among studies are problematic, and emphasis should instead be placed on identifying differences. WHC is primarily influenced by the functional properties of meat proteins and pH (Bowker et al., 2015).

The housing system had a significant effect on breast meat protein (p<0.05) and cholesterol (p<0.01) values, while no significant effect was observed on thigh meat protein, cholesterol, and fat values in either carcass part (p>0.05). In the FRS and CRS systems, protein values in thigh meat were determined as 20.61 and 18.96 (p>0.05), fat values as 14.03 and 14.93 (p>0.05), and cholesterol values as 66.62 and 74.25 (p>0.05), respectively, while in breast meat, protein values were determined as 24.67 and 21.85 (p<0.05), fat values as 4.11 and 3.98 (p>0.05), and cholesterol values as 47.93 and 66.06 (p<0.01).

According to Giampietro-Ganeco et al. (2020), the cholesterol content in the breast meat of chickens raised in organic and free-range systems was lower than that of those raised under conventional conditions. While the housing system significantly affected the protein and cholesterol content of carcass parts, no significant effect was observed on the fat contents. Çapan et al. (2021) reported that the protein contents of thigh meat in organic and conventional housing systems were 19.99% and 18.29%, respectively, while breast meat protein values were 22.24% and 22.34%. The authors concluded that the housing system significantly affected crude protein (CP) content, and breast meat consistently showed higher protein levels than thigh meat. Similar trends were observed by Chen et al. (2016), which is consistent with the findings of the present study. Regarding fat contents, the effect of the housing system on the fat value of thigh and breast meat was not significant; however, thigh meat showed a higher fat content than breast meat. Çapan et al. (2021) reported fat content of 7.96-7.97% in thigh meat and 2.05-1.50% in breast meat of broilers raised in organic and conventional systems, and noted that housing systems had a significant effect. The higher fat content observed in thigh meat in the present study is consistent with these findings. Free-range rearing systems are generally associated with favorable meat quality characteristics, including lower fat content (Michalczuk et al., 2014; Michalczuk et al., 2017), but inconsistent results have also been reported (Funaro et al., 2014). Furthermore, studies on carcass and meat quality characteristics of hatched hens reared in free-range and cage systems are limited (Semwogerere et al., 2018). Therefore, the present results regarding fat content in the male Atak-S laying hen genotype should be interpreted within this broader context.

The housing system had no significant effect on the color characteristics of thigh and breast meat (p>0.05). In thigh meat, color L* values were determined as 53.55 and 51.41 (p>0.05), color a* values as 6.44 and 5.95 (p>0.05), color b* values as 12.32 and 12.11 (p>0.05), H° values as 62.38 and 63.66 (p>0.05), C* values as 13.95 and 13.54 (p>0.05), and ΔE values as 55.57 and 53.30 (p>0.05) respectively in the FRS and CRS systems. In breast meat, color L* values were determined as 55.48 and 54.25 (p>0.05), color a* values as 5.01 and 5.37 (p>0.05), color b* values as 16.52 and 16.05 (p>0.05), H° values as 73.17 and 71.52 (p>0.05), C* values as 17.30 and 16.94 (p>0.05), and ΔE values as 58.16 and 56.85 (p>0.05) rrespectively in the FRS and CRS systems.

The findings in this study indicating that housing systems did not significantly affect thigh and breast meat color parameters (L*, a*, b*, H°, C*, and ΔE) are consistent with previous research reporting limited or non-significant effects of production systems on poultry meat color characteristics. Silva et al. (2017) reported no significant differences in L* values between free-range and industrial broiler breast meat, although some variation in a* and b* values was observed. However, Funaro et al. (2014) reported that the rearing system significantly affected meat color parameters, including L*, a*, and b* values in chicken meat, which contrasts with the non-significant differences observed in the present study. Sarica et al. (2011) reported that rearing system affected L* and b* values but not a* in breast meat, whereas in thigh meat only b* value was significantly influenced, with no effects observed on L* and a*. In contrast, the present study found no significant differences in L*, a*, or b* values of both breast and thigh meat between housing systems (p>0.05), indicating that meat color traits were not affected by rearing system under the conditions of the current experiment. In addition, meat color characteristics in poultry have been reported to be influenced by several factors, including genotype, slaughter age, management conditions, and production system (Fletcher, 2002).

In thigh meat, no significant differences were observed between the FRS and CRS systems for ΣSFA (31.77 and 31.08; p>0.05), ΣPUFA (35.56 and 33.87; p>0.05), or P/S ratio (1.12 and 1.09; p>0.05), whereas ΣMUFA content was significantly higher in CRS compared with FRS (34.94 vs. 32.68; p<0.05). In breast meat, ΣSFA values were 33.89 and 33.30 (p>0.05), ΣMUFA values were 34.58 and 33.62 (p>0.05), and ΣPUFA values were 31.53 and 32.96 (p>0.05) in FRS and CRS systems, respectively, showing no significant differences between housing systems. However, the P/S ratio was significantly higher in CRS compared with FRS (0.99 vs. 0.93; p<0.05). These results indicate that the housing systems had limited influence on most of the fatty acid composition, with significant effects observed only for ΣMUFA in thigh meat and P/S ratio in breast meat. Overall, most fatty acid fractions (ΣSFA and ΣPUFA) were not significantly influenced by housing conditions, suggesting that lipid composition is relatively stable in different production systems under similar conditions (Castellini et al., 2002; Bogosavljević-Bošković et al., 2012). However, some studies (Küçükyilmaz et al., 2012; Giampietro-Ganeco et al., 2020) have reported more pronounced effects of rearing system on fatty acid profile, particularly increases in PUFA content and improvements in P/S ratio in free-range or outdoor access systems. These differences may stem from variations in physical activity, dietary habits, and environmental conditions.

Most individual saturated fatty acids, including lauric acid, myristic acid, palmitic acid, stearic acid, heneicosanoic acid, behenic acid, tricosanoic acid, and lignoceric acid were not significantly affected by the housing systems (p>0.05). However, heptadecanoic acid content in breast meat was significantly influenced by housing system (p<0.01), indicating a limited and muscle-specific effect of rearing conditions on the saturated fatty acid profile. Kralik et al. (2005), in their study investigating SFAs in broiler meat, reported that myristic acid and palmitic acid levels in breast meat were higher in the indoor system compared with the outdoor system (p<0.01), whereas no statistically significant differences were observed between systems for lauric acid, heptadecanoic acid, stearic acid, and behenic acid. In thigh meat, lauric acid, heptadecanoic acid, and behenic acid were not significantly affected by the rearing system (p>0.05), while myristic acid was significantly higher in the indoor system (p<0.01). In contrast, palmitic acid and stearic acid showed significantly higher values in the outdoor system (p<0.001). Giampietro-Ganeco et al. (2020), who investigated the fatty acid profile of broiler drumsticks under four different rearing systems (conventional, organic, free-range, and antibiotic-free), reported heptadecanoic acid values of 0.19, 0.12, 0.14, and 0.13, respectively. They found that the conventional system had a higher value than the other systems, whereas no differences were observed among the organic, free-range, and antibiotic-free groups. The heptadecanoic acid values reported by Giampietro-Ganeco et al. (2020) and the statistical differences observed among rearing systems are consistent with the findings of the present study. However, the results for the other SFAs were significant in the study of Giampietro-Ganeco et al. (2020), which is inconsistent with the present study. This discrepancy may be due to the different carcass parts used in the research.

Most individual MUFAs, including pentadecenoic acid, myristoleic acid, palmitoleic acid, and nervonic acid, were not significantly affected by housing system in either carcass part (p>0.05). However, oleic acid content was significantly higher in thigh meat under CRS compared with FRS (p<0.05), while no significant differences were observed in breast meat MUFA composition (p>0.05). In contrast to these findings, Giampietro-Ganeco et al. (2020) reported that the levels of myristoleic acid, palmitoleic acid, oleic acid, and nervonic acid in drumstick meat were affected by the rearing system, which may be attributed to differences in carcass part and muscle-specific lipid metabolism. Additionally, Kralik et al. (2005) reported that palmitic and oleic acid levels were not affected by the rearing system in either breast or thigh meat. In contrast, nervonic acid was found to be higher in the indoor system in both carcass parts; however, this effect was more pronounced in breast meat than in thigh meat (p<0.01 vs p<0.05). This indicates that the effects of rearing system may vary depending on muscle type.

Most individual PUFAs, including linoleic acid, alpha-linolenic acid, eicosatrienoic acid, docosahexaenoic acid, and eicosapentaenoic acid, were not significantly affected by housing system in either carcass part (p>0.05). However, gamma-linolenic acid content in thigh meat was significantly lower in CRS compared with FRS (p<0.05), and no significant differences were observed in breast meat PUFA composition (p>0.05). In contrast to these findings, Giampietro-Ganeco et al. (2020) reported that all evaluated PUFA fractions, including linoleic acid, alpha-linolenic acid, eicosatrienoic acid, docosahexaenoic acid, and eicosapentaenoic acid, were significantly affected by the rearing system in drumstick meat. Kralik et al. (2005) reported that in breast meat, alpha-linolenic acid was significantly lower in the indoor system compared with the outdoor system (p<0.05), whereas docosahexaenoic acid was significantly higher in the indoor system (p<0.001), while eicosapentaenoic acid was not significantly affected by the rearing system (p>0.05). In thigh meat, alpha-linolenic acid and docosahexaenoic acid were not significantly influenced by the rearing system (p>0.05), whereas eicosapentaenoic acid was significantly higher in the outdoor system compared with the indoor system (p<0.01). This discrepancy may be attributed to differences in carcass part, muscle-specific lipid metabolism, and experimental conditions between the studies.

CONCLUSION

The results obtained for thigh meat demonstrated that the rearing system had no significant effect on most physicochemical quality parameters or on the majority of fatty acid groups. Nevertheless, the observed differences in ΣMUFA content, particularly in oleic acid levels, suggest that thigh muscle may exhibit a degree of sensitivity to rearing conditions in terms of lipid metabolism. In breast meat, most quality traits were likewise not significantly influenced by the rearing system. However, significant changes in the PUFA:SFA ratio and in certain individual fatty acids indicate a limited but measurable response of breast muscle to rearing conditions with respect to selected lipid characteristics.

Overall, the findings indicate that the effects of rearing system on meat quality traits and fatty acid composition are limited and largely parameter-dependent. Furthermore, the magnitude and direction of these effects vary according to the specific biochemical component considered. The present results also suggest that the physicochemical and compositional characteristics of Atak-S meat may be broadly similar to those reported for slow-growing genotypes. This indicates that, with targeted modifications in breeding programs, this genotype may represent a potential genetic resource for organic and free-range production systems.

ACKNOWLEDGEMENTS

We are grateful for the research material provided in the form of experimental animals established in the Master’s study of Ökkeş Akyar, supported by KSU, BAP. (Project Number: 2018/7-14 YLS).

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DECLARATIONS

The summary of the article was presented at the IV. International Congress of the Turkish Journal of Agriculture - Food Science and Technology. April 2025. Niğde.

FUNDING

This research was supported by KSU Scientific Research Projects Coordination Unit (BAP) with project number 2019/5-23 M.

DATA AVAILABILITY STATEMENT

The data that support the findings of this study are available from the corresponding author upon reasonable request.

DISCLAIMER/PUBLISHER’S NOTE

The published papers’ statements, opinions, and data are those of the individual author(s) and contributor(s). The editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions, or products referred to in the content.

Corresponding author e-mail address

Beyhan Yeter Kahramanmaraş Sütçü İmam University, Faculty of Agriculture, Department of Animal Science, 46100, Kahramanmaraş, Türkiye. Phone: [phone] Email: [e-mail]

CONFLICT OF INTEREST

The authors declare the absence of any conflicts of interest regarding the conduct or outcomes of this study.

Section Editor:

Rodrigo Garófallo Garcia

Publication Dates

• Publication in this collection
  02 Oct 2026
• Date of issue
  2026

History

• Received
  19 June 2026
• Accepted
  02 July 2026