Variability of Meat and Carcass Quality from Worldwide Native Chicken Breeds

Effect of dietary energy levels on productivity, fat deposition, and biochemical parameters of Woorimatdag1 breeder pullets

OBJECTIVE

This study aimed to investigate effects of apparent metabolizable energy (AMEn) levels in diets on productivity, fat deposition, and biochemical parameters of Woorimatdag1 (WMD1) breeder pullets.

METHODS

A total of 240 four-week-old WMD1 breeder pullets were divided into four dietary groups with five replicates (12 birds per replicate). These groups had the following dietary energy levels: standard metabolizable energy (SME), SME-200, SME-100, and SME+100 (diets containing 2,800, 2,600, 2,700, and 2,900 kcal AMEn/kg, respectively). These pullets were provided with diets and water ad libitum until 16 weeks old.

RESULTS

Weight gain was significantly (p<0.05) higher in SME-100, SME, and SME+100 groups than in the SME-200 group. SME+100 and SME groups exhibited significantly (p<0.05) improved feed conversion ratio compared to the SME-200 group. Laying ages of 30% egg production occurred significantly (p<0.05) earlier in SME-100, SME, and SME+100 groups than in the SME-200 group. SME and SME+100 groups had significantly (p<0.05) higher liver fat (%) than the SME-200 group. Additionally, the SME+100 group had higher (p<0.05) abdominal fat (%) than other groups. However, blood parameters were not significantly different among dietary groups.

CONCLUSION

SME-100 (2,700 kcal AMEn/kg) might be suitable for improving productivity and fat deposition of WMD1 breeder pullets.

Effects of Supplementation of Different Antioxidants to Cryopreservation Extender on the Post-Thaw Quality of Rooster Semen-A Meta-Analysis

The standardization of the semen cryopreservation technique could be an effective tool in poultry for the conservation of genetic resources. During this process, the production of reactive oxygen species increases, leading to oxidative stress that causes damage to the spermatozoa. To reduce this effect, the addition of exogenous antioxidants in the cryopreservation diluent has been reported to be effective. Multiple antioxidants such as catalase, vitamin E, cysteamine, ergothioneine, and serine have been studied in roosters. Therefore, the present investigation aims to perform a meta-analysis to determine if the use of the aforementioned antioxidants added to the cryopreservation extender produces an improvement in semen quality parameters in roosters after thawing. After collecting the data, a discriminant canonical analysis was performed to determine which of the selected semen quality traits provided the most information, with hypo-osmotic swelling test (HOST), viability, and total motility variables showing the highest discriminatory power. However, according to the descriptive statistics, catalase and serine are the antioxidants that improve a greater number of seminal quality parameters, and since catalase gives the most favorable results for most of the discriminating variables, it could be the antioxidant of choice.

Effect of Supplementation of a Cryopreservation Extender with Pectoliv30 on Post-Thawing Semen Quality Parameters in Rooster Species

Sperm cryopreservation is a fundamental tool for the conservation of avian genetic resources; however, avian spermatozoa are susceptible to this process. To cope with the high production of reactive oxygen species (ROS), the addition of exogenous antioxidants is beneficial. Pectoliv30 is a substance derived from alperujo, and in this study, its effect was analyzed on seminal quality after its addition to the cryopreservation extender of roosters at different concentrations. For this purpose, 16 Utrerana breed roosters were used, and seminal collection was performed in six replicates, creating a pool for each working day with ejaculates of quality. After cryopreservation, one sample per treatment and replicate was thawed, and several seminal quality parameters were evaluated. Statistical analysis revealed numerous correlations between these variables, both positive and negative according to the correlation matrix obtained. Furthermore, the chi-squared automatic interaction detection (CHAID) decision tree (DT) reported significant differences in the hypo-osmotic swelling test (HOST) variable between groups. Moreover, results for this parameter were more desirable at high concentrations of Pectoliv30. The application of this substance extracted from the by-product alperujo as an antioxidant allows the improvement of the post-thawing seminal quality in roosters and facilitates optimization of the cryopreservation process as a way to improve the conservation programs of different endangered poultry breeds.

Data-Mining Methodology to Improve the Scientific Production Quality in Turkey Meat and Carcass Characterization Studies

The present research aims to describe how turkey meat and carcass quality traits define the interest of the scientific community through the quality standards of journals in which studies are published. To this end, an analysis of 92 research documents addressing the study of turkey carcass and meat quality over the last 57 years was performed. Meat and carcass quality attributes were dependent variables and included traits related to carcass dressing, muscle fiber, pH, colorimetry, water-holding capacity, texture, and chemical composition. The independent variables comprised publication quality traits, including journal indexation, database, journal impact factor (JIF), quartile, publication area, and JIF percentage. For each dependent variable, a data-mining chi-squared automatic interaction detection (CHAID) decision tree was developed. Carcass or piece yield was the only variable that did not show an impact on the publication quality. Moreover, color and pH measurements taken at 72 h postmortem showed a negative impact on publication interest. On the other hand, variables including water-retaining attributes, colorimetry, pH, chemical composition, and shear force traits stood out among the quality-enhancing variables due to their low inclusion in papers, while high standards improved power.

Discriminant canonical analysis as a tool for genotype traceability testing based on turkey meat and carcass traits

The present study aims to develop a statistical tool for turkey breed traceability testing based on meat and carcass quality characteristics. To this end, a comprehensive meta-analysis was performed, collecting data from a total of 75 studies approaching meat and carcass attributes of 37 turkey strains and landraces since the late 1960s. A total of 22 meat and carcass traits were considered variables, grouped in the following clusters: carcass dressing traits, muscle fiber properties, pH, colorimetry, water-capacity traits, texture-related attributes, and nutritional composition of the meat. Once the multicollinearity analysis allowed the deletion of redundant variables, cold carcass weight, slaughter weight, muscle fiber diameter, sex-female, carcass/piece weight, meat redness, ashes, pH24, meat lightness, moisture, fat, and water-holding capacity showed explanatory properties in the discriminating analysis (p < 0.05). In addition, strong positive and negative correlations were found among those variables studied. Carcass traits were positively associated, particularly slaughter weight and cold carcass weight (+0.561). Among meat physical traits, pH showed positive correlations with drip loss (+0.490) and pH24 (+0.327), and water-holding capacity was positively associated with cholesterol (+0.434) and negatively associated with collagen (-0.398). According to nutritional traits, fat and ash showed a strong correlation (+0.595), and both were negatively associated with moisture (-0.375 and -0.498, respectively). Strong negative correlations were found as well between meat protein and fat (-0.460) and between collagen and cholesterol (-0.654). Finally, the Mahalanobis distance suggested a clustering pattern based on meat and carcass characteristics that report information about interbreeding and variety proximity. This study establishes a departure point in the development of a tool for breed traceability guaranteeing aimed at enhancing distinguished, local breed-based turkey meat.

Carcass composition and physicochemical and sensory attributes of breast and leg meat from native Mexican guajolote (Meleagris g. gallopavo) as influenced by sex

The aim of the study was to compare carcass composition and physicochemical and sensory attributes of breast and leg meat from native Mexican guajolote (Meleagris g. gallopavo) as influenced by sex. For this, slaughter weight and carcass characteristics of male (n = 8 ) and female (n = 8 ) guajolotes raised traditionally under extensive systems with similar housing and feeding conditions were recorded. Also, physical characteristics, proximate composition, the fatty acid profile, and sensory attributes were determined in breast and leg meat using standard procedures. The results showed that males had higher (P < 0.001 ) slaughter weight, hot and cold carcass weights, and dressing percentage, as well as carcass part weights, while females had higher (P < 0.001 ) abdominal fat weights than males. The lightness (L * ), yellowness (b * ), and drip loss values of breast meat, as well as redness (a * ) and water-holding capacity values of leg meat, were significantly (P < 0.05 ) influenced by sex. Male breast meat had higher (P < 0.05 ) moisture content, crude protein, erucic acid (C22:1n9), ∑  MUFAs (total monounsaturated fatty acids), ∑  UFAs (unsaturated fatty acids), ∑  DFAs (desirable fatty acids), ∑  UFA /  ∑  SFA (total saturated fatty acid) ratio, ∑  PUFA (total polyunsaturated fatty acid) /  ∑  SFA ratio, and chewiness scores than females. Likewise, leg meat from males showed higher (P < 0.05 ) ash content, myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1n9c), palmitoleic acid (C16:1n7), ∑  SFAs, ∑  OFAs (odd fatty acids), thrombogenic index, and atherogenic index, whereas females had high fat content. In conclusion, it would be suggested that, from a nutritional point of view, the meat from male guajolotes was preferable to the meat from females.

Carcass Yields and Meat Composition of Roosters of the Portuguese Autochthonous Poultry Breeds: "Branca", "Amarela", "Pedrês Portuguesa", and "Preta Lusitânica"

Poultry meat is an important part of the human diet, and the valorisation of autochthonous breeds is a determinant for the sustainability of the rural areas. The increasing demand for niche products demands for better knowledge of the carcass characteristics and meat quality of these local populations. The present study aims to characterise the roosters' meat from the "Branca" (BR), "Amarela" (AM), "Pedrês Portuguesa" (PP), and "Preta Lusitânica" (PL) breeds. A total of 80 birds (n = 20 per breed) between 38 and 42 weeks old were slaughtered. The physicochemical and nutritional composition were determined in the breast and drumstick meat. The meat of the PL breed had a higher (p ≤ 0.05) pH value, the AM meat revealed a water-holding capacity (WHC) of superior value and moisture content (p ≤ 0.05), while the BR breed had the highest (p ≤ 0.05) ash content. On the other hand, it was observed that the PP meat had a higher (p ≤ 0.05) yellowness index (b*). The breast meat exhibited, in all breeds, a lower pH value, WHC, redness (a*), and lipid content and greater (p ≤ 0.05) lightness (L*), b*, moisture, and ash and protein contents compared to the drumstick. Furthermore, it presented higher (p ≤ 0.05) K, P, and Mg contents and a superior proportion of total and sensorial relevant amino acids. Regarding the fatty acid profile, the breed differences were more significant in the drumstick, with the AM breed lipids presenting a higher (p ≤ 0.05) percentage of MUFAs in the fat, a lower atherogenic index, and a higher (p ≤ 0.05) value for the hypocholesterolemic/hypercholesterolemic fatty acids ratio, while the BR breed lipids presented a higher (p ≤ 0.05) percentage of PUFAs and PUFAs/SFAs ratio and a lower n-6/n-3 ratio. Considering the results obtained, it can be concluded that the meat from these breeds is a wholesome dietary option, distinguished by a favourable overall nutritional composition marked by elevated protein content, reduced lipid amounts, and amino and fatty acid profiles with desirable nutritional indices.

Study of Meat and Carcass Quality-Related Traits in Turkey Populations through Discriminant Canonical Analysis

The present research aimed to determine the main differences in meat and carcass quality traits among turkey genotypes worldwide and describe the clustering patterns through the use of a discriminant canonical analysis (DCA). To achieve this goal, a comprehensive meta-analysis of 75 documents discussing carcass and meat characteristics in the turkey species was performed. Meat and carcass attributes of nine different turkey populations were collected and grouped in terms of the following clusters: carcass dressing traits, muscle fiber properties, pH, color-related traits, water-retaining characteristics, texture-related traits, and meat chemical composition. The Bayesian ANOVA analysis reported that the majority of variables statistically differed (p < 0.05), and the multicollinearity analysis revealed the absence of redundancy problems among variables (VIF < 5). The DCA reported that cold carcass weight, slaughter weight, sex-male, carcass/piece weight, and the protein and fat composition of meat were the traits explaining variability among different turkey genotypes (Wilks' lambda: 0.488, 0.590, 0.905, 0.906, 0.937, and 0.944, respectively). The combination of traits in the first three dimensions explained 94.93% variability among groups. Mahalanobis distances cladogram-grouped populations following a cluster pattern and suggest its applicability as indicative of a turkey genotype's traceability.

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.