Breed effect between Mos rooster (Galician indigenous breed) and Sasso T-44 line and finishing feed effect of commercial fodder or corn

Carcass and meat quality of red-winged tinamou (Rhynchotus rufescens) selected for muscle growth

The aim of the present study was to evaluate the efficiency of selection for body growth and its association with carcass and meat quality traits in the red-winged tinamou. Two experimental groups were selected based on the selection index: selection group with a higher index (TinamouS) and commercial group with a lower index (TinamouC). Weight at 180 days and slaughter weight were significantly higher (p < 0.05) in the TinamouS group, as were hot carcass weight, skinless breast weight, wing weight, and thigh and drumstick weight. The meat quality traits or sensory attributes did not differ significantly (p > 0.05) between groups. A significant positive correlation (0.59; p < 0.05) was found between shear force and chewability and a significant negative correlation (- 0.59; p < 0.05) between aroma intensity and strange aroma. The present study suggests that the selection index promotes greater body growth and preserves meat quality and sensory traits in red-winged tinamou.

Data Mining as a Tool to Infer Chicken Carcass and Meat Cut Quality from Autochthonous Genotypes

The present research aims to develop a carcass quality characterization methodology for minority chicken populations. The clustering patterns described across local chicken genotypes by the meat cuts from the carcass were evaluated via a comprehensive meta-analysis of ninety-one research documents published over the last 20 years. These documents characterized the meat quality of native chicken breeds. After the evaluation of their contents, thirty-nine variables were identified. Variables were sorted into eight clusters as follows; weight-related traits, water-holding capacity, colour-related traits, histological properties, texture-related traits, pH, content of flavour-related nucleotides, and gross nutrients. Multicollinearity analyses (VIF ≤ 5) were run to discard redundancies. Chicken sex, firmness, chewiness, L* meat 72 h post-mortem, a* meat 72 h post-mortem, b* meat 72 h post-mortem, and pH 72 h post-mortem were deemed redundant and discarded from the study. Data-mining chi-squared automatic interaction detection (CHAID)-based algorithms were used to develop a decision-tree-validated tool. Certain variables such as carcass/cut weight, pH, carcass yield, slaughter age, protein, cold weight, and L* meat reported a high explanatory potential. These outcomes act as a reference guide to be followed when designing studies of carcass quality-related traits in local native breeds and market commercialization strategies.

Carcass and Meat Quality Traits of Males and Females of the "Branca" Portuguese Autochthonous Chicken Breed

Simple Summary

Local breeds play a crucial role in the rural economies of many countries, as a considerable valuable genetic resource and, well adapted to the environment, their production can reduce the negative impact of intensive production systems. Portuguese chicken breeds are almost extinct, with the “Branca” population presenting the most worrying situation. Bred as a dual-purpose breed, the characterization of meat quality is fundamental to the conservation and promotion of this population., by increasing the value on these small-scale farms production. The carcass characteristics and meat quality of the “Branca” breed were evaluated, showing an interesting physicochemical profile, with good proportion of minerals, essential fatty acids (EFA) and n-3-PUFAs (docosapentanoic (C22:5n-3, DPA), and docosahexaenoic (C22:6n-3, DHA) acids), ensuring that consumers receive a highly nutritional and differentiated product.

Abstract

The “Branca” breed is a dual-purpose Portuguese autochthonous chicken breed, produced in extensive systems and in small flocks, especially in the Entre Douro and Minho regions. A total of 40 birds (n = 20/sex) were slaughtered between 38 and 42 weeks (males) and 110 and 120 weeks (females), and carcass and meat quality parameters were evaluated. The results showed significantly higher weights and differences for males between sexes and pieces (p ≤ 0.05) in the meat physicochemical composition. Water holding capacity (WRC), moisture and ash contents were influenced by sex. They were higher in males in the breast and drumstick and lightness (L*) and lipid content were higher in females (p ≤ 0.05). The breast meat presented greater lightness, moisture, ash and protein contents, while the drumstick showed a higher pH value, redness (a*) and lipid content, in both sexes (p ≤ 0.05). Regarding the nutritional properties, “Branca” meat revealed a good proportion of minerals and the female meat showed, in both pieces (p ≤ 0.05), significantly lower values for total saturated fatty acids (SFAs) and higher values for monounsaturated fatty acids (MUFAs). Breast meat was richer in n-3-PUFAs (C22:5n-3 and C22:6n-3) in both sexes (p ≤ 0.05). Considering the results obtained, it can be concluded that “Branca” breed meat is a healthy food characterized by a good general nutritional profile.

Muscle oxidative stability, fatty acid and amino acid profiles, and carcass traits of broiler chickens in comparison to spent laying hens

This research compared muscle oxidative stability, meat composition, and carcass traits in commercial broilers and spent laying hens. At week 65 of age, 40 ISA Brown laying hens were randomly selected to create 10 replicate cages (4 birds per cage). Also, 60 day-old Ross chicks were equally divided into six replicates (10 chicks each). Broiler chickens had a higher dressing percentage than spent hens (P = 0.027), but a lower abdominal fat percentage (P = 0.009). Spent hens had higher level of malondialdehyde (MDA) in the breast muscles (P = 0.001). Meanwhile, the MDA levels in thigh muscles did not differ in both groups (P = 0.328). Broiler chickens showed greater concentrations of saturated fatty acids (palmitic and stearic) in the breast (P = 0.012 and 0.006, respectively) and thigh (P = 0.033 and 0.038, respectively) muscles as compared to spent hens. Meanwhile, broiler chickens had lower concentrations of palmitoleic, oleic and eicosapentaenoic in the breast muscles (P = 0.002, 0.004 and 0.001, respectively). Also, spent hens had greater concentrations of linoleic in the breast and thigh muscles (P = 0.018 and 0.035, respectively). When compared to broiler chickens, spent hens had greater essential amino acids (isoleucine, methionine and tyrosine) concentrations in the breast muscles (P = 0.002, 0.001 and 0.036, respectively). Finally, while broiler chickens had superior carcass traits, spent hens showed better meat composition (higher polyunsaturated fatty acids and essential amino acids). Furthermore, the oxidative stability of the breast muscles of spent hens was lower than that of broilers. Spent hens can be used as an attractive source of chicken meat if certain precautions are adopted.

Variability of Meat and Carcass Quality from Worldwide Native Chicken Breeds

The present research aimed to determine the differential clustering patterns of carcass and meat quality traits in local chicken breeds from around the world and to develop a method to productively characterize minority bird populations. For this, a comprehensive meta-analysis of 91 research documents that dealt with the study of chicken local breeds through the last 20 years was performed. Thirty-nine traits were sorted into the following clusters: weight-related traits, histological properties, pH, color traits, water-holding capacity, texture-related traits, flavor content-related nucleotides, and gross nutrients. Multicollinearity problems reported for pH 72 h post mortem, L* meat 72 h post mortem, a* meat 72 h post mortem, sex, firmness, and chewiness, were thus discarded from further analyses (VIF < 5). Data-mining cross-validation and chi-squared automatic interaction detection (CHAID) decision tree development allowed us to detect similarities across genotypes. Easily collectable trait, such as shear force, muscle fiber diameter, carcass/pieces weight, and pH, presented high explanatory potential of breed variability. Hence, the aforementioned variables must be considered in the experimental methodology of characterization of carcass and meat from native genotypes. This research enables the characterization of local chicken populations to satisfy the needs of specific commercial niches for poultry meat consumers.

Effect of Breed and Diet on Carcass Parameters and Meat Quality of Spent Hens

Two spent hen breeds (Mos and Isa Brown) fed with three different diets [commercial feeding (CF); corn, pea, and triticale (CPT); and corn and wheat (CW)] were studied to assess their laying performance, carcass characteristics, and meat quality parameters (breast and drumstick). A total of 48 hens reared in a traditional free-range system were used. Birds were slaughtered at 72 weeks of age after the moulting in an accredited abattoir, and measurements (for each bird) of carcass and meat started at 24 h post-mortem. The results demonstrated a breed and diet effect (P<0.05) on laying performance, carcass, and meat quality. The Mos breed showed lower laying performance, higher live weight (P<0.001), carcass weight (P<0.001), dressing percentage (P<0.001), and carcass fat (P<0.001) than Isa Brown. The breed also affected physicochemical parameters of drumstick and breast (P<0.05). Concerning the diet effect, spent hens fed with commercial feeding showed heavier live weight (P<0.01) and carcass weight (P<0.01). Diet significantly affected most of meat quality parameters, CPT being the formulation that most affected (P<0.05) drumstick composition, while in the breast was CF (P<0.001). Significant (P≤0.005) effects on breast colour, cooking loss and hardness were observed in animals fed with alternative diets to CF. Regarding nutritional quality, no breed or diet effect (P<0.05) was observed in MUFA s, PUFA s and n-6 contents of meat. Overall, both breeds showed a high protein and low-fat content in the breast, showing these hens as an opportunity for the development of meat products as well as an economic purpose for spent hens that reach the end of their productive lives.

Effect of different feed restriction regimens on performance, behaviors, blood cortisol, and carcass parameters of growing Sasso broilers

The aim of this study was to evaluate the effect of different feed restriction regimens on performance, behavioral patterns, blood cortisol, and carcass parameters in Sasso broilers. Sixty healthy 1-day-old unsexed Sasso chicks were randomly assigned to three groups (20 chicks per group) and each group was divided into 4 replicates with 5 chicks each based on feed restriction program during the rearing period (60 days). The first group (G1) is control in which birds were fed ad libitum had free access to feed (no restriction). The second group (G2) was subjected to temporary feed restriction at the first 2 weeks as birds had access to feed for 12 h only after that they had free access to feed until the end of the experimental period. The third one (G3) was subjected to continuous feed restriction as birds had free access to feed for 12 h only throughout the rearing periods. During the study period, growth performance and behavioral patterns were estimated. At the end of the study, blood samples for cortisol testing were taken. Three birds from each group were slaughtered at the end of the study to see how the feed restriction affected carcass parameters. Feed restriction had a substantial impact (P ≤ 0.05) on final body weight and carcass parameters. Feed restriction elevated blood cortisol significantly (P = 0.004). Feed restriction showed a significant impact on some behaviors as feeding, stretching, preening, and aggression. Overall, different feed restriction programs had a wide effect on growth performance, behaviors, cortisol concentration, and carcass parameters of Sasso broilers.

Effect of L-theanine on meat quality, muscle amino acid profiles, and antioxidant status of broilers

This study investigated the effect of L-theanine on carcass traits, meat quality, muscle antioxidant capacity, and amino acid (AA) profiles of broilers. Three hundred 1-day-old Ross 308 male broilers were randomly allotted to five groups with six replicates. Birds were fed the basal diet or basal diet with 300, 600, 900, or 1,500 mg/kg L-theanine for 42 consecutive days. The results showed that L-theanine quadratically increased dressing percentage, eviscerated percentage, and leg muscle yield (p < .05). Meanwhile, drip loss, cooking loss, shear force, L*_24h, and muscle lactate content decreased quadratically in response to dietary L-theanine supplementation (p < .05), while pH_24h and muscle glycogen content were quadratically improved by L-theanine (p < .05). Notably, the contents of muscle malondialdehyde and protein carbonyl, and the activities of muscle total antioxidant capacity, catalase, and glutathione peroxidase decreased quadratically in response to dietary L-theanine supplementation (p < .05), suggesting that the oxidative stress level of muscle was decreased quadratically. Moreover, L-theanine quadratically increased the concentrations of most of muscle essential AA, nonessential AA, and flavor AA (p < .05). In conclusion, L-theanine can be used as a valuable feed additive to modulate carcass traits, meat quality, muscle antioxidant status, and AA profiles of boilers, and its optimum addition level is 600 mg/kg based on the present study.

Effect of Age and Genotype of Native Breed Cockerels on Carcass and Meat Quality

The aim of the study was to determine meat quality in cockerels of two multipurpose breeds reared to different ages. The study involved 30 cockerels each of two native breeds: Yellowleg Partridge (Ż-33) and Rhode Island Red (R-11). The results showed that cockerels of the native breeds Rhode Island Red (R-11) and Yellowleg Partridge (Ż-33) represent a good starting material for niche production of poultry meat R-11 cockerels exhibited a better rate of weight gain and their carcasses had higher yellowness and redness values compared to Ż-33 birds. The carcasses of both cockerel breeds had lower breast and higher leg muscle percentage, and their meat contained more collagen and protein and less fat. As birds aged, body weight and abdominal fat percentage increased, and giblets percentage decreased in the cockerels of both breeds, whereas in the R-11 breed dressing percentage increased, leg bone percentage decreased, yellowness (a*) increased and redness (b*) decreased. Neither genotype nor slaughter age had a significant effect on chemical composition of the breast and leg muscles. In both breeds, the breast and leg muscle quality traits were more affected by age than genotype.

Production of Marine Probiotic Bacteria in a Cost-Effective Marine Media Based on Peptones Obtained from Discarded Fish By-Products

The industrial production of marine bacteria with probiotic properties is limited by the excessive cost of the culture media adequate for their growth. The present work aimed to study the suitability of 30 marine media formulated with nitrogen sources (fish peptones) from different fish discards and seawater, for the growth of two marine probiotic bacteria (MPB), namely Phaeobacter sp. and Pseudomonas fluorescens. These fish peptones were produced from several discarded fish and by-products (heads, skins, and whole individuals of megrim, mackerel, gurnard, hake, etc.). In all cultivations, no significant differences were found on cell viability when the microorganism grew on commercial or alternative media. In relation to the biomass production, the growth of Phaeobacter sp. on waste media was commonly similar or a 20% lower than observed in the control cultures. For P. fluorescens, various peptones (skin peptones of pouting and blue whiting) showed even higher productive ability than commercial peptones. An initial economical evaluation revealed that low-cost media reduced until 120 times the cost of production of MPB.

Proximate Composition, Amino Acid Profile, and Oxidative Stability of Slow-Growing Indigenous Chickens Compared with Commercial Broiler Chickens

The increased demand for chicken meat products has led to chickens with increased growth rates and heavier slaughter weights. This has had unintentional negative effects on the genetics of these animals, such as spontaneous, idiopathic muscle abnormalities. There has also been a shift in customer preference towards products from alternative farming systems such as organic and free-range. Indigenous purebred chickens, such as the Polverara, show potential in these systems as they are adapted to more extensive systems. The aim of the present study was to characterize the meat quality traits of the Polverara, by comparing the proximate composition and amino acid profile with that of a commercial Hybrid. In addition, the lipid and protein oxidation was analyzed after eight days of storage. A total of 120 leg meat samples, 60 Polverara and 60 Hybrid were analyzed. Polverara exhibited higher protein content, lower lipid content, and a better amino acid profile. These results indicate that the Polverara has better nutritional meat quality. However, Polverara also showed higher levels of lipid and protein oxidation. Therefore, further research is needed, especially in regards to the fatty acid profile and mineral content of the meat, which is known to affect oxidative stability.

Effect of chilling methods on the surface color and water retention of yellow-feathered chickens

This study was conducted to investigate the effects of air chilling (AC), water chilling (WC), combined chilling consisting of WC for 20 min and AC (CO₂₀), and combined chilling consisting of WC for 30 min and AC (CO₃₀) on the microbiological status, surface color, processing yield, and moisture content of yellow-feathered chicken carcasses. After chilling, the carcasses treated by AC exhibited the highest total viable counts (TVC) (4.7 cfu/cm²), followed by those treated by CO₂₀ and CO₃₀, whereas the carcasses treated by WC showed the lowest (P < 0.05) mean log TVC (4.2 cfu/cm²). Based on an instrumental color evaluation and photographs of carcass surfaces, the carcasses treated by AC showed a notable yellow color (P < 0.05), whereas no significant difference (P > 0.05) was found among the carcasses treated by CO₂₀, CO₃₀, and WC. The skin samples of carcass parts treated by WC (breast, thighs, drumsticks, back, neck, and wings) exhibited higher moisture contents than the skin samples of the carcasses treated by AC (P < 0.05), providing evidence that weight gain during WC is due to higher water absorption by the skin. The different parts of the broiler carcasses treated by AC had lower cooking losses than those of carcasses treated by combined chilling or WC (P < 0.05), except for the thighs and claws. In breast and drumstick muscles, the moisture contents of the superficial parts from carcasses treated by WC were higher than those of the carcasses treated by AC, whereas the internal parts were not significantly affected by the chilling methods (P > 0.05). The results of this work can be useful for understanding and improving the chilling process for yellow-feathered chickens.

Effect of Breed and Diet Type on the Freshness and Quality of the Eggs: A Comparison between Mos (Indigenous Galician Breed) and Isa Brown Hens

Eggs are a nutritious food, offering a balanced source of essential amino and fatty acids, minerals, and vitamins. Genetic and diet factors can modify hen egg traits. Thus, the effects of breed and feed on egg quality using two laying hens, Mos (autochthonous breed) and Isa Brown (commercial hybrid), and three feeds, commercial fodder (CF), corn/pea/triticale (CPT) and corn/wheat (CW), were investigated. Freshness parameters (egg weight, eggshell weight and thickness, albumen height, Haugh units and yolk color), chemical composition, color and textural parameters, as well as fatty acid profile, were assessed on a total of 288 eggs, from the two breeds. The samples were divided in 96 eggs, corresponding to each of the three dietary treatments. There were significant differences (p < 0.001) in albumen height and Haugh units, obtaining the highest values for Isa Brown genotype; meanwhile, laying hens fed with CF had the highest weight, as well as the greatest eggshell thickness. Cooked yolks of Isa Brown eggs presented the highest values of luminosity, while the yellowness was higher for Mos eggs. Regarding the texture of eggs, genotype was again the parameter having the greatest impact, obtaining higher values in hardness, gumminess and chewiness in those eggs from the Mos breed. Concerning egg chemical composition, it was affected by breed and diet type, but Mos eggs were characterized by a significantly (p < 0.001) higher contents of fat (9.53% vs. 7.58%), protein (12.31% vs. 11.66%) and ash (1.10% vs. 1.04%) than Isa Brown ones. Finally, diet type influenced the fatty acid profile, mainly affecting oleic and linoleic acids, which showed significantly (p < 0.05) highest values (42.90 and 14.66 g/100 g of total fatty acids) in CW and CF diets, respectively. Overall, breed and bird diet factors had a strong effect on egg quality and nutritional profile. Moreover, eggs from Mos hens had more attractive nutritional indices, and they could even be improved more by changing the diet.

Meat quality of poulards obtained from three conserved breeds of hens

The aim of the study was to determine the effect of genotype (breed/line) and spaying of pullets on body weight, estradiol level, carcass and meat quality. Subjects were Rhode Island Red (R-11), Yellowleg Partridge (Ż-33) and Sussex hens (S-66), 100 birds per line, which were divided into 2 groups, each having 50 pullets and 50 poulards. Spaying was performed at 10 wk of age, under local anesthesia by a veterinarian. The present study showed that blood estradiol levels in poulards were much lower than in pullets regardless of genotype. Poulards showed higher body weight and their carcasses higher lightness and yellowness. In the sensory evaluation, poulard breast meat was more tasty and leg meat also more juicy and tender compared to pullet meat. Among the three conserved breeds, Rhode Island Red (R-11) and Yellowleg Partridge (Ż-33) hens are the best starting material for poulard production. Their carcasses showed good muscling and intense yellowness desirable to the consumers. R-11 birds achieved highest body weight. Spaying of pullets had no significant effect on the profile of fatty acids, but greater and statistically significant differences in this regard were found between hen lines. Compared to S-66 birds, breast muscles of R-11 and Ż-33 birds contained more polyunsaturated fatty acids (PUFA). The breast and leg muscles of these birds had a lower content of saturated fatty acids (SFA ).

Effect of Organic Production System on the Performance and Meat Quality of Two Purebred Slow-Growing Chicken Breeds

The objective of the study was to compare the effect of organic and conventional rearing systems on the productivity and meat quality of Yellowleg Partridge (Ż-33) and Rhode Island Red (R-11) chickens. A total of 492 sexed experimental birds (Gallus domesticus) were assigned to four groups. In groups I-C and III-C, the Ż-33 and R-11 chickens were reared under intensive conditions following conventional farming principles. In groups II-O and IV-O, the Ż-33 and R-11 chickens were kept according to organic farming principles. Body weight, feed conversion (kg/kg gain) and mortality were recorded throughout the study. On day 140 of rearing, the native breed chickens were subjected to simplified slaughter analysis, and meat pH, muscle colour, water holding capacity and chilling loss were determined. The meat samples were analysed for the chemical composition and profile of fatty acids, and the peroxidizability index (PI), thrombogenic index (TI) and atherogenicity index (AI) were calculated. The organically raised chickens were characterised by higher body weight (P≤0.01), better feed conversion (P≤0.01) and more favourable fatty acid profile of the muscles compared to the conventionally reared birds. Under organic conditions, the R-11 chickens showed better productivity but slightly poorer fatty acid profile of the muscles compared to the Ż-11 chickens.

Differences in Physicochemical and Nutritional Properties of Breast and Thigh Meat from Crossbred Chickens, Commercial Broilers, and Spent Hens

The objective of this study was to compare the physicochemical and nutritional properties of breast and thigh meat from commercial Chinese crossbred chickens (817 Crossbred chicken, 817C), imported commercial broilers (Arbor Acres broiler, AAB), and commercial spent hens (Hyline Brown, HLB). The crossbred chickens, commercial broilers and spent hens were slaughtered at their typical market ages of 45 d, 40 d, and 560 d, respectively. The results revealed that several different characteristic features for the three breeds. The meat of the 817C was darker than that of the other two genotypes. The 817C were also characterized by higher protein, lower intramuscular fat, and better texture attributes (cooking loss, pressing loss and Warner-Bratzler shear force [WBSF]) compared with AAB and HLB. The meat of the spent hens (i.e. HLB) was higher in WBSF and total collagen content than meat of the crossbred chickens and imported broilers. Furthermore, correlation analysis and principal component analysis revealed that there was a clear relationship among physicochemical properties of chicken meats. With regard to nutritional properties, it was found that 817C and HLB exhibited higher contents of essential amino acids and essential/non-essential amino acid ratios. In addition, 817C were noted to have highest content of microelements whereas AAB have highest content of potassium. Besides, 817C birds had particularly higher proportions of desirable fatty acids, essential fatty acids, polyunsaturated/saturated and (18:0+18:1)/16:0 ratios. The present study also revealed that there were significant differences on breast meat and thigh meat for the physicochemical and nutritional properties, regardless of chicken breeds. In conclusion, meat of crossbred chickens has some unique features and exhibited more advantages over commercial broilers and spent hens. Therefore, the current investigation would provide valuable information for the chicken meat product processing, and influence the consumption of different chicken meat.

A Kinetic and Factorial Approach to Study the Effects of Temperature and Salinity on Growth and Toxin Production by the Dinoflagellate Alexandrium ostenfeldii from the Baltic Sea

Alexandrium ostenfeldii is present in a wide variety of environments in coastal areas worldwide and is the only dinoflagellate known species that produces paralytic shellfish poisoning (PSP) toxins and two types of cyclic imines, spirolides (SPXs) and gymnodimines (GYMs). The increasing frequency of A. ostenfeldii blooms in the Baltic Sea has been attributed to the warming water in this region. To learn more about the optimal environmental conditions favoring the proliferation of A. ostenfeldii and its complex toxicity, the effects of temperature and salinity on the kinetics of both the growth and the net toxin production of this species were examined using a factorial design and a response-surface analysis (RSA). The results showed that the growth of Baltic A. ostenfeldii occurs over a wide range of temperatures and salinities (12.5-25.5°C and 5-21, respectively), with optimal growth conditions achieved at a temperature of 25.5°C and a salinity of 11.2. Together with the finding that a salinity > 21 was the only growth-limiting factor detected for this strain, this study provides important insights into the autecology and population distribution of this species in the Baltic Sea. The presence of PSP toxins, including gonyautoxin (GTX)-3, GTX-2, and saxitoxin (STX), and GYMs (GYM-A and GYM-B/-C analogues) was detected under all temperature and salinity conditions tested and in the majority of the cases was concomitant with both the exponential growth and stationary phases of the dinoflagellate's growth cycle. Toxin concentrations were maximal at temperatures and salinities of 20.9°C and 17 for the GYM-A analogue and > 19°C and 15 for PSP toxins, respectively. The ecological implications of the optimal conditions for growth and toxin production of A. ostenfeldii in the Baltic Sea are discussed.