Turkey Muscle Research Articles

Fatty acid composition of turkey breast muscle and the salutogenic feeding regimen formulations (a pilot study)

Fatty acid composition of turkey breast muscle and the salutogenic feeding regimen formulations (a pilot study)

The effect of raw and fermented rapeseed cake on growth performance, carcass traits, and breast meat quality in turkey

The objective of this study was to determine the effect of including 15% of raw or fermented rapeseed cake (RRC or FRC) in turkey diets on growth performance, carcass traits, and breast meat characteristics. A total of 1,350 day-old female Hybrid Converter turkeys were allocated to 3 dietary treatments (9 replicates per treatment and 50 birds each) and fed complete isocaloric and isonitrogenous diets. In the control group, soybean meal was the main source of dietary protein, whereas the experimental groups were fed diets containing 15% of RRC or FRC. The fermentation of rapeseed cake reduced the content of glucosinolates and phytate-phosphorus. In comparison with RRC, turkeys receiving FRC achieved significantly higher final BW, comparable with that noted in the control group. The experimental factor had no effect on carcass dressing percentage or carcass fat content, whereas turkeys fed diets containing rapeseed cake were characterized by lower relative weight of breast muscles and higher relative gizzard weight. The muscles of birds from groups RRC and FRC had also significantly lower cholesterol concentration. In comparison with control diet, diets RRC and FRC contributed to a significant decrease in the levels of saturated fatty acids and an increase in the share of n-6 polyunsaturated fatty acids in the total fatty acid pool in breast meat. The highest concentrations of n-3 polyunsaturated fatty acids and the most desirable n-6/n-3 polyunsaturated fatty acid ratio were noted in the breast muscles of RRC group turkeys. Both RRC and FRC reduced catalase and superoxide dismutase activity, and decreased the malondialdehyde content of muscle tissue. In conclusion, the replacement of RRC with FRC in diets led to an increase in the final BW of turkeys, but it had no influence on carcass quality and the majority of meat quality traits. The inclusion of rapeseed products in turkey diets positively affected meat quality, improving the fatty acid profile and antioxidant status, but it also decreased the yield of breast muscles.

Fumonisin B1, B2 and B3 in Muscle and Liver of Broiler Chickens and Turkey Poults Fed with Diets Containing Fusariotoxins at the EU Maximum Tolerable Level.

Although provisional maximum tolerable daily intake and recommended guidelines have been established for fumonisins (FB) in food, few data are available concerning levels of FB in edible animal tissues. Such data are of particular interest in avian species that can tolerate relatively high levels of fumonisins in their feed. Also, even if multiple contamination of animal feed by toxins produced by Fusarium is very frequent, little is known about the consequences of multiple contamination for FB levels in tissues. The aim of this study was to analyze the concentrations of FB in the muscle and liver of chickens and turkeys fed with FB alone and with FB combined with deoxynivalenol (DON), and with zearalenone (ZEN). Experimental diets were formulated by incorporating ground cultured toxigenic Fusarium strains in corn-soybean based feeds. Control diets were free of mycotoxins, FB diets contained 20 mg FB1+FB2/kg, and FBDONZEN diets contained 20, 5, and 0.5 mg/kg of FB1+FB2, DON, and ZEN, respectively. Animals were reared in individual cages with free access to water and feed. The feed was distributed to male Ross chickens from the 1st to the 35th day of age and to male Grade Maker turkeys from the 55th to the 70th day of age. On the last day of the study, the birds were starved for eight hours, killed, and autopsied for tissues sampling. No sign of toxicity was observed. A UHPLC-MS/MS method with isotopic dilution and immunoaffinity clean-up of samples has been developed for analysis of FB in muscle (n = 8 per diet) and liver (n = 8 per diet). Only traces of FB that were below the LOQ of 0.25 µg/kg were found in most of the samples of animals fed with the control diets. Mean concentrations of FB1, FB2, and FB3 in muscle were 17.5, 3.39, and 1.26 µg/kg, respectively, in chickens, and 5.77, 1.52, and 0.54 µg/kg in turkeys, respectively. In the liver, the respective FB1, FB2, and FB3 concentrations were 44.7, 2.61, and 0.79 µg/kg in chickens, and 41.47, 4.23, and 1.41 µg/kg, in turkeys. Cumulated level of FB1+FB2+FB3 in the highly contaminated samples were above 60 and 100 µg/kg in muscle and liver, respectively. The concentrations of FB in the tissues of animals fed the FBDONZEN diet did not greatly differ from the concentrations measured in animals fed the diet containing only FB.

Chemical composition, physical and chemical properties and biological value of turkey muscle and adipose tissues using biogenic stimulants

The effectiveness of the biogenic stimulants action based on the larvae of the SITR bees drone brood and adult individuals of the ST drones on the chemical composition, physical and chemical, commodity technological properties, nutritional and biological value of the muscle and fatty tissues in young turkeys is studied. The turkey-poults of the 1st group received injections of a physiological salt solution, and the 2nd and 3rd experimental groups, respectively, of the SITR and ST biological stimulants, three times at the age of 1, 7 and 14 days at a dose of 0.1 ml per 50 g of live weight. It was established that in the middle sample of the muscle tissue in turkeys of the 2nd and 3rd experimental groups there were less water and more dry matter and protein. Biogenic stimulants contributed to the synthesis of muscle tissue in turkeys of the 2nd and 3rd experimental groups, in which contained 1.79 (B>0.999) and 1.31 (B>0.99) absolute % more protein and 0.32 and 0.23 absolute % less fat than in the control group. In the muscle tissue of turkeys stimulated with biogenic preparations, there were more tryptophan by 1.63 and 0.84 mg% and by 0.92 and 0.54 mg% less hydroxyproline than in turkeys at the same age of the control group. The protein-quality index of muscle tissue was higher in turkeys of the 2nd and 3rd experimental groups by 3.08 and 1.72% than in the control. The first place in the overall assessment of meat and broth quality was taken by the turkeys from the 2nd experimental group; the second place was taken by the turkeys of the third experimental group. Their superiority over the control group was 0.151 and 0.109 points, respectively. The fatty tissue of turkeys in all experimental groups has good quality and high digestibility indices. It has in its composition a large amount of polyunsaturated fatty acids; this indicates its high biological value.

Fatty Acid Composition of Female Turkey Muscles in Kazakhstan

Fatty Acid Composition of Female Turkey Muscles in Kazakhstan

Relating neuromuscular control to functional anatomy of limb muscles in extant archosaurs.

Electromyography (EMG) is used to understand muscle activity patterns in animals. Understanding how much variation exists in muscle activity patterns in homologous muscles across animal clades during similar behaviours is important for evaluating the evolution of muscle functions and neuromuscular control. We compared muscle activity across a range of archosaurian species and appendicular muscles, including how these EMG patterns varied across ontogeny and phylogeny, to reconstruct the evolutionary history of archosaurian muscle activation during locomotion. EMG electrodes were implanted into the muscles of turkeys, pheasants, quail, guineafowl, emus (three age classes), tinamous and juvenile Nile crocodiles across 13 different appendicular muscles. Subjects walked and ran at a range of speeds both overground and on treadmills during EMG recordings. Anatomically similar muscles such as the lateral gastrocnemius exhibited similar EMG patterns at similar relative speeds across all birds. In the crocodiles, the EMG signals closely matched previously published data for alligators. The timing of lateral gastrocnemius activation was relatively later within a stride cycle for crocodiles compared to birds. This difference may relate to the coordinated knee extension and ankle plantarflexion timing across the swing-stance transition in Crocodylia, unlike in birds where there is knee flexion and ankle dorsiflexion across swing-stance. No significant effects were found across the species for ontogeny, or between treadmill and overground locomotion. Our findings strengthen the inference that some muscle EMG patterns remained conservative throughout Archosauria: for example, digital flexors retained similar stance phase activity and M. pectoralis remained an 'anti-gravity' muscle. However, some avian hindlimb muscles evolved divergent activations in tandem with functional changes such as bipedalism and more crouched postures, especially M. iliotrochantericus caudalis switching from swing to stance phase activity and M. iliofibularis adding a novel stance phase burst of activity.

Hemolysis, tocopherol, and lipid oxidation in erythrocytes and muscle tissue in chickens, ducks, and turkeys

Muscle from turkeys is more sensitive to lipid oxidation during post mortem storage compared with that of chicken and duck which may involve increased lysis of turkey erythrocytes that releases hemoglobin oxidant. Three separate experiments were conducted to study characteristics of chicken, duck, and turkey erythrocytes in which dietary tocopherols were standardized. In Experiment I, tocopherol, fatty acid composition, and lipid oxidation capacity were measured in erythrocytes from chickens, ducks, and turkeys. Tocopherol content was greater in chicken erythrocytes compared with that of duck and turkey (P < 0.05). Oleic and linoleic acid content was higher in chicken erythrocytes compared with that of turkey (P < 0.05). Lipid oxidation capacity of erythrocytes in washed turkey muscle (WTM) at pH 5.8 ranked chicken > duck > turkey (P < 0.05). In Experiment II, hemolysis was measured in erythrocytes from turkeys and chickens. Detergent-induced hemolysis (pH 7.4) was on average 12-fold greater for turkey erythrocytes compared with that of chicken (P < 0.05). In Experiment III, the ability of lysed and non-lysed erythrocytes to promote lipid oxidation was examined. Lysed erythrocytes promoted lipid oxidation in WTM more effectively than intact erythrocytes (P < 0.05). Reasons that turkey erythrocytes were more labile to detergent-induced hemolysis whereas chicken erythrocytes more effectively promoted lipid oxidation in the WTM model system are discussed. These studies describe variation in chemical and physical properties of erythrocytes from chickens, ducks, and turkeys that can influence progression of lipid oxidation in poultry muscle.

The Effect of Different Levels of Cu, Zn and Mn Nanoparticles in Hen Turkey Diet on the Activity of Aminopeptidases.

The aim of the study was to estimate the influence of the different levels of Cu, Zn, and Mn nanoparticles on the activity of aminopeptidases in turkey. An experiment was carried out on 144 turkey hen Hybrid Converter. The birds were divided into groups given standard- and nanoparticle-supplementation of different level of copper (Cu 20, 10, 2 mg/kg), zinc (Zn 100, 50, 10 ppm), and manganese (Mn 100, 50, 10 ppm), covering respectively 100%, 50%, and 10% of the physiological demands for those minerals in the diet. The activity of aminopeptidases (alanyl: AlaAP, leucyl: LeuAP and arginyl: ArgAP) after supplementation of minerals was determined in the breast and thigh turkey muscle. The strongest effect of interaction among minerals supplementation form and dose on the activity levels of the aminopeptidases in thigh muscle was observed for nano-Cu already at the lowest dose of 2 mg/kg. In this dose (covering 10% of the birds’ demand) nano form of supplementation significantly increased the activity of Ala-, Leu-, and ArgAP (877, 201, and 719, respectively), compared to standard form of supplementation (461, 90.5, and 576, respectively). In turn, in breast muscle, after supplementation covering 10% of the demand with the nano-Cu, nano-Zn, and nano-Mn compared to the standard form, we did not observe any significant difference in the activity levels of any of the investigated aminopeptidases, except for AlaAP under Zn supplementation. Supplementation with the 20 mg/kg of Nano-Cu (100% of demand) and with 10 mg/kg of Nano-Cu (50% of demand) inhibited the activity of all of the three aminopeptidases in thigh muscle. Supplementation of the minerals in nano form into the diet, especially of Cu and Zn in the dose covering 10% of the demand is relevant to maintain homeostasis in turkey muscles, as indicated by the activity of the aminopeptidases.

Walk the Walk: Parallels between Gait Parameters and Muscle Force Production in Turkeys

Running and walking involve regular patterns of limb kinematics, which can be characterized by simple parameters such as stride frequency and foot contact time. It is not clear whether these regular patterns of timing are mirrored at the level of muscle function, or whether variable sharing of force among different muscles might result in timing within individual muscles that does not reflect the timing of limb movements. We used direct measurements of force production in the lateral gastrocnemius (LG) muscle of wild turkeys during walking and running to test the hypothesis that stride parameters measured from limb movements would match those measured from muscle force production at all speeds of walking and running. Muscle force was measured via strain gauges attached to the bony tendon of the muscle, and stride parameters were measured with high‐speed video as animals ran on a treadmill at a range of walking and running speeds (1 to 3.5 m/s). Stride frequency and stride time values measured from video matched those determined from the onset of muscle force for all speeds. Time of foot contact measured from video decreased continuously with speed. Time of force development for the LG also decreased with speed, but the time spent in force development in the LG was significantly lower than the time the foot was on the ground for all speeds. The fraction of time the muscle was generating force was relatively constant across speed, with the muscle producing force for approximately 50% of the period of foot ground contact. This observation indicates that there is a temporal sharing of the task of force production between different muscles during the step, and that this sharing may remain relatively fixed across walking and running speeds. Such temporal sharing of force development should be considered in models of locomotor mechanics and energetics, and may be relevant to rehabilitative strategies for gait disorders.Support or Funding InformationThe Integrative Organismal Systems Physiology (IOSP) Undergraduate Summer Research Fellowship that made this research possible was supported by the American Physiological Society and a grant from the National Science Foundation (NSF) Integrative Organismal Systems (Award No. IOS‐1238831). Support from NIH grant AR‐055295 is also gratefully acknowledged.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Broadening the Detection Spectrum of Small Analytes Using a Two-Antibody-Designed Hybrid Immunoassay.

The recognition spectrum of immunoassays developed on the basis of class-specific antibodies can include the several nearest analytes but rarely all of the desired representatives of the group. The situation may be sufficiently improved using a hybrid assay combining two antibodies with specificities that complement each other. Two monoclonal antibodies (mAb) with broad but different specificities toward sulfonamides were examined for their binding to a panel of hapten conjugates. mAb-hapten pairs without mutual cross-reactions were identified, and classical direct antigen-coated and mAb-coated ELISAs were developed as formats with referent specificities. Both interactions were combined in a single hybrid assay, which was designed as a one-step double-competitive sandwich-ELISA. For this assay, the intermediate bifunctional reagent mAb(1)-hapten(2) conjugate was synthesized and able to simultaneously bind to hapten(1) and be bound by mAb(2). Formation of a two-mAbs sandwich complex was inhibited by competitors of interaction(1) as well as by competitors of interaction(2). Thus, due to the summation effect, simultaneous determination of analytes recognized by both mAbs was achieved. The hybrid assay can be performed in two reversed arrangements using a coating antigen or coating antibody, the characteristics of which were compared and found to be similar in sensitivity and extended specificity. The suitability of the developed test for the determination of 14 sulfonamides at their maximum residue limit (MRL) concentration was demonstrated using the examples of turkey muscle and milk samples.

Effect of Various Inoculum Levels of Multidrug-Resistant Salmonella enterica Serovar Heidelberg (2011 Ground Turkey Outbreak Isolate) on Cecal Colonization, Dissemination to Internal Organs, and Deposition in Skeletal Muscles of Commercial Turkeys after Experimental Oral Challenge.

Salmonella enterica serovar Heidelberg (S. Heidelberg) is a major foodborne pathogen colonizing poultry. The pathogen is associated with a significant number of foodborne outbreaks through contaminated poultry meat, including turkeys. Recently, multidrug-resistant (MDR) strains of S. Heidelberg have emerged as a threat to human public health in the United States. The objective of this study was to determine the cecal colonization, dissemination to internal organs, and the potential for skeletal muscle deposition of an MDR S. Heidelberg isolate from the 2011 ground turkey outbreak in the United States after the experimental oral challenge of poults (young turkeys) and adult turkey hens. In the poult study, two separate experiments using day-old, straight-run, commercial hybrid converter poults were randomly assigned to five challenge groups (0, 10∧2, 10∧4, 10∧6, 10∧8 CFU groups; 12 poults/group; N = 60/experiment) and a week after, treatment groups were challenged separately with 0-, 2-, 4-, 6-, and 8- log10 CFU of S. Heidelberg orally. After 14 days post-challenge, the poults were euthanized, and samples were collected to determine MDR S. Heidelberg colonization in the cecum, dissemination to liver and spleen, and deposition in the thigh, drumstick, and breast muscles. A similar experimental design was followed for the adult turkey hens. In two separate experiments, 11-week-old commercial Hybrid Converter turkey hens (4 hens/group; N = 20/experiment) were challenged with MDR S. Heidelberg and on day 16 post-challenge, birds were euthanized and samples were collected to determine Salmonella populations in the samples. The results indicated that, in turkey poults, the recovery of MDR S. Heidelberg was highest in the cecum followed by spleen, liver, thigh, drumstick, and breast. All tested inoculum levels resulted in more than 3.5 log10 CFU/g colonization in the poult cecum. The cecal colonization, dissemination to internal organs, and tissue deposition of MDR S. Heidelberg were high in poults. The pathogen recovery from the cecum of adult turkey hens ranged from 37.5 to 62.5% in the challenge groups. The results signify the importance of controlling MDR S. Heidelberg in turkeys at the farm level to improve the safety of turkey products.

Comparison of plasma corticosterone concentration, muscle fibre diameter, and apoptotic markers between normal and pale, soft, exudative (PSE) turkey breast muscles

The increasing production potential of birds is correlated with a lower health and immune potential, resulting in the appearance of numerous meat quality defects. The greatest concern for gallinaceous poultry (chickens and turkeys) is PSE meat, which is characterized by light colour, soft texture and a reduced water-binding capacity. The aim of the study was to compare plasma corticosterone concentration, muscle fibre diameter, and the apoptotic markers between normal and pale, soft, exudative (PSE) turkey breast muscles. The results show, that the PSE group is characterized by a significantly higher plasma corticosterone concentration and a significantly greater muscle fibre diameter at 30 min post mortem compared to the normal group. The time of refrigerated storage (4°C) of meat contributes significantly to reducing muscle fibre diameter in the PSE group at 24 h post mortem compared to 30 min post mortem. Additionally, the results obtain showed that the caspase-3 activity at 30 min post mortem increased significantly in the turkey breast muscles of PSE compared with the normal group. Moreover, the PSE group demonstrated the higher apoptotic potential measured in the breast muscle of turkey compared with the normal group. It is stated from the obtained results that the incidence of PSE meat in turkeys may be associated with their higher susceptibility to stress factors and stressinduced pathological states.

Response of Turkey Muscle Satellite Cells to Thermal Challenge. II. Transcriptome Effects in Differentiating Cells.

Background: Exposure of poultry to extreme temperatures during the critical period of post-hatch growth can seriously affect muscle development and thus compromise subsequent meat quality. This study was designed to characterize transcriptional changes induced in turkey muscle satellite cells by thermal challenge during differentiation. Our goal is to better define how thermal stress alters breast muscle ultrastructure and subsequent development.Results: Skeletal muscle satellite cells previously isolated from the Pectoralis major muscle of 7-wk-old male turkeys (Meleagris gallopavo) from two breeding lines: the F-line (16 wk body weight-selected) and RBC2 (randombred control line) were used in this study. Cultured cells were induced to differentiate at 38°C (control) or thermal challenge temperatures of 33 or 43°C. After 48 h of differentiation, cells were harvested and total RNA was isolated for RNAseq analysis. Analysis of 39.9 Gb of sequence found 89% mapped to the turkey genome (UMD5.0, annotation 101) with average expression of 18,917 genes per library. In the cultured satellite cells, slow/cardiac muscle isoforms are generally present in greater abundance than fast skeletal isoforms. Statistically significant differences in gene expression were observed among treatments and between turkey lines, with a greater number of genes affected in the F-line cells following cold treatment whereas more differentially expressed (DE) genes were observed in the RBC2 cells following heat treatment. Many of the most significant pathways involved signaling, consistent with ongoing cellular differentiation. Regulation of Ca2+ homeostasis appears to be significantly affected by temperature treatment, particularly cold treatment.Conclusions: Satellite cell differentiation is directly influenced by temperature at the level of gene transcription with greater effects attributed to selection for fast growth. At lower temperature, muscle-associated genes in the satellite cells were among the genes with the greatest down regulation consistent with slower differentiation and smaller myotubes. Fewer expression differences were observed in the differentiating cells than previously observed for proliferating cells. This suggests the impact of temperature on satellite cells occurs primarily at early points in satellite cell activation.

Valorization of underutilized North American pawpaw (Asimina triloba): investigation as a lipid oxidation inhibitor in turkey homogenate model system.

The objective of this study was to characterize the ability of extracts from nine varieties of pawpaw pulp standardized to the phenolics level of 0.1% grape seed extract (GSE) on inhibition of the formation of thiobarbituric reactive substances (TBARS) in a turkey model system. The antioxidant activity of the extracts was also determined using four common assays. Over the 240 min sampling time, the standardized pawpaw extracts from all nine varieties were as effective as GSE in inhibiting TBARS formation in turkey muscle homogenate compared to the untreated control. Extracts from all pawpaw varieties and GSE began to inhibit TBARS formation at 60 min of incubation, and by 240 min TBARS were reduced from 35 μmol malondialdehyde kg-1 tissue in the homogenate to which no antioxidant was added to 4-18 μmol malondialdehyde kg-1 tissue in the antioxidant-enriched extracts. There does not appear to be a clear relationship between inhibition of TBARS and any of the antioxidant capacity measurements (ORAC, DPPH inhibition, reducing potential as measured by FRAP assay, or pyrogallol red bleaching). The results of this research indicate that there is potential to add value to pawpaw as a functional food source of natural antioxidants, particularly in meat products. © 2017 Society of Chemical Industry.

Early and 24 h post-mortem thigh (ilio tibialis) muscle metabolism and meat quality in two genetic types of turkeys and their reciprocal crosses, raised under semi-confined conditions

ABSTRACT1. The experiment was conducted in order to determine the effect of the direction of turkey crossing on quality traits of their thigh muscle.2. In total, 1358 turkeys of slow- (SG) and fast-growing (FG) lines as well as SF crosses (SG × FG) and FS crosses (FG × SG) were reared with access to free range to 21 weeks of age in the case of males and 15 weeks of age in the case of hens.3. After slaughter of 15 males and 15 hens from each genetic line, their thigh muscles were examined and the following traits were measured after 5-min, 45-min, 2-h and 24-h post-mortem: temperature, pH, glycogen content (G), lactate content (L) and electrical conductivity (EC). Quality attributes were evaluated based on chemical composition, water holding capacity, cooking loss (%) and colour.4. The rate of post-mortem changes in temperature, G, L and pH in muscles differed among the 4 lines of turkeys, with the highest metabolic rate determined for muscles of SG turkeys, followed by muscles of SF, FS and FG birds. A more beneficial muscle water holding capacity of both sexes of turkeys and better results of cooking loss in male muscles were found in SG and SF turkeys. The thigh muscles of the crosses were characterised by a higher content of protein and a lower content of fat compared to the muscles of FG turkeys, and in the case of the males also by a higher protein content compared to the muscles of SG birds.5. Owing to the faster post-mortem metabolism, better water holding capacity, lower cooking loss and fat content at a similar content of protein, the thigh muscles of SF crosses raised in the free range system represent a better quality of meat for consumers compared to the thigh muscles of FS turkeys.

Dioxins and PCBs in ostrich meat and eggs: levels and implications

ABSTRACTAlthough consumption of eggs is an essential part of our diet, limited information is available for table eggs other than those laid by hens. The aim of our study was to determine concentrations of polychlorinated dibenzofurans (PCDD/Fs), dioxin-like (DL-) and non-dioxin-like (NDL) polychlorinated biphenyls (PCBs) in ostrich eggs and meat available on the Polish market, in order to obtain baseline information on the current status of these pollutants in comparison to poultry products. Obtained data were compared with the binding EU limits set for chicken eggs and meat. The levels of individual PCDD/Fs and PCBs congeners varied considerably. The percentage share of total WHO toxic equivalency factor (WHO-TEQ) content indicates the dominant role of PCDD/Fs. High concentrations of PCDD/F and DL-PCBs, in the range of 0.85–74.48 pg WHO-TEQ g−1 fat, were found in ostrich eggs; this exceeds the maximum level permitted for chicken eggs by a factor of up to 15. Eight of the 11 egg samples exceeded the action level for hen eggs. Although the ostrich meat concentrations of PCDD/Fs do not exceed the limit established for poultry muscle (1.75 pg g−1 fat), average contents of PCDD/Fs exceeded almost four times the levels in chicken and turkey muscle. Human exposure was evaluated and the resulting risk was characterised. Taking into account the low average consumption of ostrich eggs, the resulting exposure to dioxins for the general population can be considered as negligibly low. However, the individuals who frequently consume such eggs may be at risk of elevated exposure. Although ostrich products are not consumed frequently, such data are nevertheless useful for food safety purposes.

Response of turkey muscle satellite cells to thermal challenge. I. transcriptome effects in proliferating cells

BackgroundClimate change poses a multi-dimensional threat to food and agricultural systems as a result of increased risk to animal growth, development, health, and food product quality. This study was designed to characterize transcriptional changes induced in turkey muscle satellite cells cultured under cold or hot thermal challenge to better define molecular mechanisms by which thermal stress alters breast muscle ultrastructure.ResultsSatellite cells isolated from the pectoralis major muscle of 7-weeks-old male turkeys from two breeding lines (16 weeks body weight-selected and it’s randombred control) were proliferated in culture at 33 °C, 38 °C or 43 °C for 72 h. Total RNA was isolated and 12 libraries subjected to RNAseq analysis. Statistically significant differences in gene expression were observed among treatments and between turkey lines with a greater number of genes altered by cold treatment than by hot and fewer differences observed between lines than between temperatures. Pathway analysis found that cold treatment resulted in an overrepresentation of genes involved in cell signaling/signal transduction and cell communication/cell signaling as compared to control (38 °C). Heat-treated muscle satellite cells showed greater tendency towards expression of genes related to muscle system development and differentiation.ConclusionsThis study demonstrates significant transcriptome effects on turkey skeletal muscle satellite cells exposed to thermal challenge. Additional effects on gene expression could be attributed to genetic selection for 16 weeks body weight (muscle mass). New targets are identified for further research on the differential control of satellite cell proliferation in poultry.

Pectoralis major muscle of turkey displays divergent function as correlated with meat quality

Fresh turkey meat color is determined by many factors that include muscle fiber type composition and heme protein concentrations. These factors either are affected by or influence biochemical events occurring postmortem. Deviations in the processing environment also can result in aberrant fresh meat quality and may ultimately change the quality characteristics of further processed products. Our objective was to describe the underlying cause and significance of the two-toning color defect in fresh turkey breast. In the first experiment, pectoralis major muscles were collected, classified as single- or two-toned, and analyzed using image processing to characterize fresh turkey color. Samples from the large and small lobes of the pectoralis major muscle were collected for pH, glycolytic intermediates, protein abundance, mRNA expression, and quality characteristics. In the second experiment, time from stun to exsanguination was tested as a promoter of fresh turkey color. Results from the first experiment showed that the turkey breast possesses two distinct lobes. The large lobe had greater (P < 0.05) glycolytic potential, lactate content, lactate dehydrogenase (LDH) abundance, and centrifugal drip loss, while pH, myoglobin mRNA expression, and soluble protein levels were lower (P < 0.05) compared to the small lobe. Results from the second experiment showed that reducing time from stun to exsanguination enhanced (P < 0.05) fresh turkey color by mitigating the differences between the two lobes. Our results also showed that birds exsanguinated first had greater (P < 0.05) muscle pH values and body temperatures. These results show inherent differences in breast muscle and processing conditions interact to establish variations in fresh turkey color.

The Fatty Acid Profile and Oxidative Stability of Meat from Turkeys Fed Diets Enriched with n-3 Polyunsaturated Fatty Acids and Dried Fruit Pomaces as a Source of Polyphenols.

The aim of this study was to determine the efficacy of different dietary fruit pomaces in reducing lipid oxidation in the meat of turkeys fed diets with a high content of n-3 polyunsaturated fatty acids (PUFAs). Over a period of 4 weeks before slaughter, turkeys were fed diets with the addition of 5% dried apple, blackcurrant, strawberry and seedless strawberry pomaces (groups AP, BP, SP and SSP, respectively) and 2.5% linseed oil. Pomaces differed in the content (from 5.5 in AP to 43.1 mg/g in SSP) and composition of polyphenols Proanthocyanidins were the main polyphenolic fraction in all pomaces, AP contained flavone glycosides and dihydrochalcones, BP contained anthocyanins, and SP and SSP—ellagitannins. The n-6/n-3 PUFA ratio in all diets was comparable and lower than 2:1. In comparison with groups C and AP, the percentage of n-3 PUFAs in the total fatty acid pool of white meat from the breast muscles of turkeys in groups BP, SP and SSP was significantly higher, proportionally to the higher content of α-linolenic acid in berry pomaces. The fatty acid profile of dark meat from thigh muscles, including the n-6/n-3 PUFA ratio, was similar and lower than 3:1 in all groups. Vitamin A levels in raw breast muscles were higher in group AP than in groups C and BP (P<0.05). The addition of fruit pomaces to turkey diets lowered vitamin E concentrations (P = 0.001) in raw breast muscles relative to group C. Diets supplemented with fruit pomaces significantly lowered the concentration of thiobarbituric acid reactive substances (TBARS) in raw, frozen and cooked meat. Our results indicate that the dietary application of dried fruit pomaces increases the oxidative stability of meat from turkeys fed linseed oil, and strawberry pomace exerted the most desirable effects due to its highest polyphenol content and antioxidant potential.

Water diffusion to assess meat microstructure

In the quest for setting up rapid methods to evaluate water retention ability of meat microstructures, time domain nuclear magnetic resonance (TD-NMR) has gained a prominent role, due to the possibility to observe water located outside the myofibrils, easily lost upon storage or cooking. Diffusion weighted signals could be used to monitor the shape and dimension of the pores in which water is confined, thus boosting the information offered by TD-NMR. The work outlines a parsimonious model to describe relative abundance and diffusion coefficient of intra and extra myofibrillar water populations, exchange rate between them, diameter of the myofibrillar cells. To test our model, we registered diffusion and T2 weighted NMR signals at 20MHz on fresh meat from pectoralis major muscle of 100days old female turkey. We then purposely altered water distribution and myofibrils shape by means of freezing. The model predicted nicely the consequences of the imposed modifications.