Comparison of Carcass Characteristics, Meat Quality, and Blood Parameters of Slow and Fast Grown Female Broiler Chickens Raised in Organic or Conventional Production System

Abstract

The objective of the study was to compare the carcass characteristics, meat quality, and blood parameters of slow and fast grown female broiler chickens fed in organic or conventional production system. The two genotypes tested were medium slow-growing chickens (SG, Hubbard Red JA) and commercial fast-growing chickens (FG, Ross 308). Both genotypes (each represented by 400 chickens) were divided into two sub-groups fed either organic (O) or conventional (C) systems. Chickens of each genotype and system were raised in a semi environmentally controlled poultry house until 21 d of age and were assigned to 5 pens of 40 chickens each. Then, O system chickens were transferred into an open-side poultry house with an outdoor run. At 81 d of age, 10 female chickens from each genotype and from each production system (n = 40) were randomly chosen to provide material for analysis, and were weighed and brought to the slaughterhouse to assess carcass characteristics and meat quality. The blood parameters were determined by using 5 female chickens from each genotype and from each production system (n = 20). FG had the higher live weight, along with carcass, breast, and thigh-drumstick weights compared to SG (p<0.05). FG had the higher breast yield, whereas SG had the higher thigh-drumstick yield (p<0.05). The O system resulted in a higher amount of abdominal fat (p<0.05). In addition, the O system values were higher for dry matter, crude ash, crude protein, and pH15 values in breast meat, and for crude ash, crude protein, and pH15 values in drumstick meat (p<0.05). In addition, total saturated fatty acids, total mono-unsaturated fatty acids, and total omega 3 were significantly higher in the O system than in the C system. Thus, the O system showed a positive advantage compared to the C system regarding female chicken meat quality, primarily within the ash, protein, and total omega 3 fatty acid profiles. In conclusion, the present study indicated that the main factor affecting the carcass characteristics of female chickens was genotype, whereas the organic system contributed to enhanced meat quality. These findings provide a better understanding of the relative roles of genotype and production systems in female broiler characteristics, and might aid producers in designing their facilities to optimize yield and quality while maintaining acceptable animal welfare standards.

Fatty acid composition of breast meat in two lines of slow-growing chickens reared conventionally or on pasture

“…Similar to us, Michalczuk et al (2017) reported lower levels of SFA in the breast meat of slowgrowing chickens reared outdoors on pasture when compared to the indoors system, however they observed higher MUFA content in the pastured chickens. Cömert et al (2016) observed increased content of SFA and MUFA in the drumstick of both fast and slow-growing chicken genotypes when reared in organic system with pasture access compared to conventional system, and also surprisingly reported decreased content of the ω-6 and ω-3 PUFA in the chickens from the pastured groups. This contradicts to our results concerning the contents of SFA, MUFA and PUFA.…”

Difference in the Carcass Quality and Meat Chemical Composition in Two Lines of Slowgrowing Chickens With or Without Access to Pasture

“…Similarly, Poltowicz and Doktor (2011) showed that free range with pasture decreased the live weight in the chickens, but only in the male ones. On the other hand, Cömert et al (2016) observed significantly higher live weight in fast-growing chickens, reared outdoors, but no effect of the rearing system in slow-growing lines. Our results are in line with Wang et al (2009) who reported lower live weight in slow-growing chickens reared free-range with access to grass paddocks and Li et al (2017) in medium -growing chickens raised indoors on floor and outdoors with pasture.…”

“…One of the major goals in the poultry meat industry is to reduce the carcass fatness and mainly the deposition of the abdominal fat (Fouad and El-Senousey, 2014). Jiang et al (2011) and Li et al (2017) found significant decrease in the abdominal fat as a result of the pasture rearing, while Cömert et al (2016) observed generally increased abdominal fat in outdoor reared lines, more pronounced in the fast growing ones. No effect of pasture was detected on the percentage of the deposited abdominal fat in our study, which is in agreement with the results of Mikulski et al (2011) and Chen et al (2013).…”

“…Protein content did not differ between rearing systems and lines in breast, however in thigh meat significantly lower content was observed in the pastured birds, corresponding to the increased lipid content. Several studies reported increased protein content in meat of the outdoors reared birds (Fanatico et al, 2007;Mikulski et al, 2011;Cömert et al, 2016), while others did not find significant effect of the rearing systems on this trait (Wang et al, 2009;Sosnówska-Czajka et al, 2017). The ash content in breast meat was lower in the pastured birds (P<0.001) but significant difference was found also between the lines (P<0.01).…”

Meat quality characteristics of chickens as influenced by housing system, sex, and genetic line interactions

“…Concomitant with this interest in slower growing chickens for meat is an emerging scientific literature on production systems (e.g. Fanatico et al 2015;Comert et al 2016;Stadeg et al 2017) and meat quality (e.g. De Marchi et al 2005;Fanatico et al 2007) of these chickens.…”