Pectoralis Superficialis Research Articles

Effects of Selective Breeding for Voluntary Exercise, Chronic Exercise, and Their Interaction on Muscle Attachment Site Morphology in House Mice

Skeletal muscles attach to bone at their origins and insertions, and the interface where tendon meets bone is termed the muscle attachment site (or enthesis). Muscle attachment sites function to anchor muscles/tendons to bone and to dissipate stress (force per unit area) resulting from force transmission. Mechanical stresses at the muscle/tendon‐bone interface are proportional to surface area of the bony attachment sites, so a larger muscle attachment site will distribute loads over a wider surface area. Muscles that are frequently active and/or are of larger size should cause muscle attachment sites to hypertrophy (training effect), so paleontological studies have often used characteristics of attachment sites as indicators of locomotor behavior.In studies of humans, muscle attachment sites have been used to infer physical activity of fossil specimens, with larger attachment sites assumed to indicate larger muscles and/or habitual use. For example, muscle attachment site morphology was examined in prehistoric Andean fishing and agricultural populations. From this data, anthropologists concluded that the fishing population had more muscular upper bodies while the agricultural population had more muscular lower bodies. Such differences in muscle attachment site morphology have been attributed to differences in physical activity levels and loading history of limb bones experienced by individuals during their lifetime. However, bone performance during loading is governed by both genetic factors and loading history, but also by age, sex, and epigenetic factors. Thus, controversy arises when paleontologists attempt to infer the past loading history (i.e., activity levels) of individuals from bone morphology.We studied 4 replicate lines of high runner (HR) mice that had been selectively bred for 57 generations based on the average number of wheel revolutions on days 5 & 6 of a 6‐day period of wheel access. Four additional lines have been bred without regard to wheel running and serve as controls (C). On average, mice from HR lines voluntarily run ~3 times more than C mice on a daily basis. We housed 100 mice with or without wheels for 12 weeks starting at weaning. We quantified the evolved differences in muscle attachment site morphology between HR and C mice as well as plastic changes resulting from chronic exposure to exercise by measuring the cortical cross‐sectional areas, linear dimensions, and total surface area for muscles that attach on the femur and humerus. Sites chosen for subsequent analysis included the femoral third trochanter, an insertion point for the quadratus femoris, and the humerus deltoid crest, an insertion point for the spinodeltoideus, superficial pectoralis, and acromiodeltoideus.With body mass as a covariate, HR mice had significantly larger humerus deltoid tuberosities than C, with no significant training effect. Morphology of the femoral third trochanter did not differ between HR and C mice and was unaffected by chronic wheel access. Our results suggest that muscle attachment site morphology is largely determined by genetic background rather than exercise during ontogeny.3D Model of the Femoral Third Trochanter of a MouseFigure 1

Pathological consequences of low atmospheric pressure stunning in broiler chickens

Low atmospheric pressure stunning (LAPS) is a novel approach to pre-slaughter stunning of chickens using progressive hypobaric hypoxia by the application of gradual decompression (280s cycle) according to a set of prescribed pressure curves. Low atmospheric pressure stunning produces a non-recovery state. Concerns have been raised relating to the possible pathological and welfare consequences of expansion of air in the body during LAPS. In a randomised trial, we compared the gross pathology of broilers exposed to LAPS with a control group euthanised by intravenous injection of pentobarbital sodium (60 mixed sex broilers per treatment). The birds were exposed to each treatment in triplets and all birds were subject to necropsy examination to detect and score (1 to 5, minimal to severe) haemorrhagic lesions or congestion for all major organs and cavities (e.g. air sacs, joints, ears and heart) as well as external assessment for product quality (e.g. wing tips). Behavioural data (latency to loss of posture and motionless) and chamber cycle data (temperature, humidity, pressure and oxygen availability) confirmed that LAPS had been applied in a manner representative of the commercial process. All of the organs observed were structurally intact for both treatment groups. No lesions were observed in the external ears, oral cavity, tracheal lumen, crop and air sacs of birds from either treatment group. There was no difference between treatments in the wingtips, nasal turbinates, thymus, biceps femoralis and colon. Haemorrhagic lesions were observed in the calvaria, brains, hearts and lungs of both treatment groups, but lesions in these areas were more severe in the LAPS treatment group. It was not possible to distinguish between pathological changes induced by decompression or recompression. In the barbiturate group, more severe haemorrhagic lesions were observed in the superficial pectoral muscles as well as greater congestion of the infraorbital sinuses, liver, spleens, duodenum, kidneys and gonads. These findings provide evidence that LAPS did not result in distension of the intestines and air sacs sufficient to cause changes, which were grossly visible on postmortem examination. There was also no evidence of barotrauma in the ears and sinuses. The pathological changes observed in the barbiturate treatment were as expected based on barbiturate toxicity. Low atmospheric pressure stunning appears to produce pathological changes by a variety of well-established mechanisms, and while these pathological data have limited value as welfare indicators, the results confirm that organ integrity was not compromised by the process.

Differences in Breast Muscle Mitochondrial Respiratory Capacity, Reactive Oxygen Species Generation, and Complex Characteristics between 7-week-old Meat- and Laying-type Chickens.

The skeletal muscle growth rate is a major feature differentiating meat- and laying-type chickens. A large amount of ATP is required during skeletal muscle synthesis, in which mitochondrial energy production capacities play a significant role. Additionally, mitochondria may participate in muscle protein degradation via reactive oxygen species generation. To investigate the differences in mitochondrial energetic characteristics between chickens exhibiting different growth rates, this study evaluated respiratory capacities in response to different types of respiratory substrate, protein abundances, assembly of individual respiratory complexes (I–V) and supercomplexes, and reactive oxygen species generation rates. These characteristics were compared between mitochondria from the breast muscle (M. pectoralis superficialis) of seven-week-old meat- and laying-type male chickens. Blue native polyacrylamide gel electrophoresis analysis revealed that meat-type chickens exhibited a significantly lower protein abundance of complex III (cytochrome bc1 complex), complex V (F0F1 ATP synthase), and total amount of supercomplexes than did laying-type chickens. There were no differences between chicken types in the respiration rate of mitochondria incubated with either pyruvate/malate or succinate, each of which drives complex I- and complex II-linked respiration. Carnitine palmitoyltransferase-1-dependent and -independent respiration during ATP synthesis and carnitine palmitoyltransferase-2 enzymatic activity were significantly lower in meat-type chickens than in layingtype chickens. For mitochondria receiving pyruvate/malate plus succinate, the reactive oxygen species generation rate and its ratio to the oxygen consumed (the percentage of free radical leak) were also significantly lower in meat-type chickens than in laying-type chickens. These results suggested that the mitochondrial energetic capacities of the breast muscle of meat-type chickens could be lower than those of laying-type chickens at seven weeks of age. Furthermore, the lower reactive oxygen species generation rate in meat-type chickens might have implications for rapid muscle development, which is possibly related to their lower muscle protein degradation rates.

Особенности микроорганизации поверхностной грудной мышцы у кур мясного и яичного направлений продуктивности

On the basis of histological and micromorphometric studies, general patterns and breed features of the structural organization of the superficial pectoral muscle in meat (Smena-8, Cobb-500) and egg (Hisex white, Andalusian blue) productivity directions are presented. The age of the examined individuals is 29 days. The study evaluated the structural and morphometric parameters of not only muscle fibers, but also the connective tissue component of the muscle under study. It is shown that representatives of meat breeds surpass representatives of egg breeds in terms of muscle fiber thickness and perimisia. At the same time, the indicators of the thickness of the endomysium, bundles of muscle fibers and the area of muscle tissue had similar values in all studied birds. The data obtained indicate the presence of both common morphological traits of muscle tissue, genetically determined and stable regardless of productivity, and variable, which can change under the influence of selection. The research results are important for biology, comparative, species and breed morphology, as well as for veterinary and sanitary examination of chicken meat and in poultry farming to assess the purity of the breed.

Investigation 0f Beef Brisket Palatability from Three USDA Quality Grades

ObjectivesBarbecuing and smoked meat continues to grow in popularity for food service and consumers at home. However, little research has examined the eating quality differences of point (pectoralis superficialis) and flat (pectoralis profundi) muscles across USDA quality grade. The objective of this study was to investigate differences in smoked beef brisket palatability from three USDA quality grades.Materials and MethodsBeef briskets from the USDA Prime, Average Choice, and Select quality grades (n = 54; 18 per treatment) were collected at a commercial abattoir in Omaha, NE. Briskets were trimmed to 6 mm of external fat, seasoned with a blend of 1:1 coarse kosher salt/coarse black pepper by hand (0.05% of the brisket raw weight), and were held at 2–4° for 12 h prior to cooking. Briskets were cooked in an electric pellet smoker utilizing Gold Blend Hardwood Pellets (red oak, hickory, and maple wood) for ∼4 h to an internal temperature of 63°C; wrapped in aluminum foil, placed back in the smoker for ∼4 h, and cooked to 93°C, then held in an insulated cooler until slicing. Approximately 90 min prior to serving, briskets were separated in point and flat portions, and then sliced (6 mm × 50 mm x cooked depth) perpendicular to the muscle fiber for consumer evaluation and held in warmers at (∼50°C) until serving. Each consumer (n = 360) received six test samples representing all quality grade × muscle combinations to evaluate tenderness, juiciness, flavor liking, overall liking, as well as the acceptability of these traits. Additionally, willingness to pay (WTP) was collected on an individual sample basis.ResultsAn interaction between quality grade and muscle was observed (P ≤ 0.03) for all palatability traits, proportion of acceptable samples, and WTP. Consumers could not distinguish between quality grades of the point portions for tenderness, juiciness, flavor and overall liking (P > 0.05). Point samples, regardless of quality grade were scored greater than Prime flat samples, which were intermediate (P < 0.05). Consumers similarly (P > 0.05) scored Choice and Select flat samples lower for all palatability traits compared to all other treatment combinations. In alignment with palatability traits, consumers were willing to pay the most for point portions, regardless of quality grade (P < 0.05). Consumers WTP of the Prime flat portion was intermediate, and consumers were willing to pay the least for Choice and Select flat portions (P < 0.05).Consumer acceptability followed similar trends as palatability scores. However, a greater proportion of consumers classified Choice and Select point samples as acceptable than that of Prime point samples in all categories of acceptability (P < 0.05). Consumers struggled to distinguish differences in acceptability for Choice and Select flat portions (P > 0.05) in all factors except juiciness acceptability.ConclusionQuality grade had no effect on the eating quality of the point portions of smoked briskets, and point portions received superior palatability scores to flat portions. Briskets from the Prime flat portions had greater eating quality than Choice and Select briskets from the flat portion, and consumers were willing to pay more for what they perceived as superior eating quality. This data suggests that unless consumers prefer the flat portion of the brisket there is no benefit to paying the premium for a prime brisket from a palatability standpoint.

Effects of in ovo injection of prebiotics and synbiotics on the productive performance and microstructural features of the superficial pectoral muscle in broiler chickens

The aim of the study was to compare the effects of 2 prebiotics and 2 synbiotics injected in ovo on productivity parameters, quality, and microstructure of the superficial pectoral muscle in 35-day-old broiler chickens. On day 12 of incubation, 9,000 eggs Ross 308 were randomly divided into 5 experimental groups treated with different bioactives in ovo injected: C, control with physiological saline; PI, with 1.760mg inulin; PB, with 0.528mg of commercial prebiotic Bi2tos; SI, with 1.760mg inulin and 1,000 CFU Lactococcus lactis spp. lactis IBB SL1; SB, with 0.528mg Bi2tos and 1,000 CFU Lactococcus lactis spp. cremoris IBB SC1. The synbiotic solution contained 20μl bacterial suspension and 180μl prebiotic solution. For productive parameters and further tests ten male birds for each experimental group were used. The birds were slaughtered on day 35 of age. At slaughter, samples of the left pectoral muscles were taken and preserved by freezing in liquid nitrogen. The pH and color of the meat were evaluated at 45 min and 24 h post-mortem. Water holding capacity (WHC) was measured and expressed as the percentage of free water in meat. Microscopic specimens were analysed using MultiScan software for the measurement of the percentage of oxidative and glycolytic fibres and mean diameter of the muscle fibres. In ovo injection of prebiotics Bi2tos had a positive effect on body weight. In prebiotic group (PI) a negative impact on hatchability was observed. Prebiotics and synbiotics had no influence on the yield of the carcass and pectoral muscle. Bioactive compounds had a significant effect on the quality of meat parameters such as: pH 24h (PI and PB group), L* 45' (SI and SB group), and WHC (groups PB, SI, and SB). The analysis of the enzymatic profile showed a significant increase in the percentage of glycolytic fibres in the pectoral muscle from chicken treated with a synbiotic with the addition of inulin (group SI).

The Use of Syrian Sumac (Rhus coriaria) as a Meat Tenderizer: Effect on Fat, Protein and Collagen Profiles on Pectoralis superficialis Cut

The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic importance in food, cosmetic and pharmaceutical industries. Meat tenderness is one of the very most important factors for customers‘ acceptability. The global objective of this study was to add an additional value to Sumac by evaluating its meat tenderizing effect. Crude sumac fruits were used to create three different extracts (aqueous, ethanolic and purified enzymatic extract). Pectoralis superficialis cuts were treated with the extracts and studied for their shear stress, pH, protein and fat contents and collagen. The hypothesis that Sumac could have a meat tenderizing effect was supported by our results showing a significant decrease in shear stress and protein content with increase in collagen solubility. Moreover, an effect on decreasing meat fat was detected, where the aqueous sumac extract decreased significantly the fat percentage in meat. The active enzymes in Sumac were shown to be variate in nature, lipase and protease, with a significant effect on collagen, thus proving Sumac‘s possibility to be potentially used as a meat tenderizer.

Physical characteristics of quail (Coturnix coturnix) meat given hydrolyzed feather meal from broiler at different levels

The quail (Coturnix-coturnix) is a type of bird that has recently been widely cultivated. One factor that can affect the physical quality of quail meat is feeding. The need for food ingredients for protein sources is necessary to meet the protein needs in the quail. Hydrolyzed feather of broiler chicken meals is a feed material that has a high protein content, but low potency digestibility. It is expected that the hydrolysis process improves the digestibility in feather meal. The level of digestibility of the ingredients will affect the rate of metabolism of nutrients (proteins) in the body of the quail. The metabolic process of the protein compounds also has the potential to influence the characteristics of quail meat. The purpose of this study was to evaluate the characteristics of quail meat by eating broiler feathers resulting from the hydrolysis process of feed at different levels. This study used 100 heads quail one week old, body weight range 140-180g, (unsex). The study was designed using a completely randomized design (CRD) unidirectional a 4 x 5 pattern. A total of four types of feeding treatment has been applied in this study, namely: (T0 = 0%, T1 = 1%, T2 = 1.5 and T3 = 2%. Each treatment was repeated five times. The number of treatment units was a 4 x 5 = 20 treatment units. Each treatment unit used five head quails as samples. The observation process was carried out for 30 days. On the 30th, the slaughtering process was carried out and then the meat quality test was continued. The test samples of the quality of the meat were obtained from the chest muscular (Pectoralis superficialis). Observations of parameters include: (1) the water holding capacity (WHC), (2) cooking loss (CL) and (3) meat shear force (MSF). The data obtained were analyzed statistically using ANOVA. The results of the research data show significant effect and then Duncan’s test. The results showed that the treatment of the feather meal hydrolyzed at different levels significantly (p<0.05) in the WHC, CL, and MSF. The WHC value of breast meat (Pectoralis superficialis) in the range of 32.42± 6.24-49.48±11.63%, CL (3.05±2.00-22.30±14.26%) and MSF (0.56±0.26-0.99±0.10 kg/cm2). The use of feeds from the broiler meal at 1.5% (T2) level shows the characteristics of quail meat better than other treatments.

ANALISIS PROFIL ASAM LEMAK DAGING AYAM PETELUR AFKIR YANG DIFERMENTASI SECARA TRADISIONAL BALI MENGGUNAKAN GAS CHROMATOGRAPHY-MASS SPECTROMETRY (GC-MS)

This study was aimed to determine the fatty acids profile in fermented products of chicken breast meat (Musculus pectoralis superficialis) of spent hen layer using Gas Chromatography Mass Spectrophotometric technique. The chicken used was of Isa Brown strain after a period of laying of 76 weeks which was obtained from some local farms in Tabanan, Denpasar, and Gianyar - Bali. The chicken meat was cut into small pieces then mixed with ground spices concisting of galangal, coriander, garlic, brown sugar, salt, white pepper and coconut oil. The batter meat was mixed evenly and then wrapped with upih, in which both ends were tied with a rope followed by drying under the sun for 5 days (natural fermentation process). The profile of the fermented chicken meat was integrated and presented descriptively. The results showed that the fermented meat contained higher bioactive component of fatty acids such as oleic acid, palmitic acid and linoleic acid compared to that of the control, but lower stearic acid content. It was also evident that the cholesterol content was the lowest at the end of drying.

MEAT COLOUR CHARACTERISTICS OF DIFFERENT PRODUCTIVE TYPES DOMESTIC QUAILS

The aim of the present study was to investigate the meat colour characteristics, using CIE L*a*b* colour description system, of quails from the two main production types reared in Europe: the intermediate heavy (dual-purpose) and heavy (meat-type). Quails were separated by gender in male and female subgroups, as follows: Am, Af, Dm, Df, Mm and Mf, where A group was dual-purpose and D and M groups were from heavy type. Meat colour characteristics of the breast (M. pectoralis superficialis), tenders (M. pectoralis profundus) and leg muscles (M. Iliotibialis lateralis pars postacetabularis) were evaluated on post mortem hour 24 in CIE L*a*b* colour description system. On the basis of L*, a* and b* values, the chroma (С*), colour index (CI) and meat colour index (MCI) were calculated. The lateral surface of M. p. superficialis was substantially darker in the light all-purpose type than in the heavy group М (р&lt;0.001). The lowest lightness values (L*) were detected on M. p. superficialis facies medialis and the outer surface of M. p. profundus. The highest average meat redness was detected on M. p. superficialis facies medialis and the lowest - in thigh muscles (M. iliotibialis). Average yellowness (b*) of all studied muscles were positive in all groups of quails, with statistically significantly lower values in females vs males. The sex-related analysis showed that indices CI and MCI were considerably lower for both surfaces of M. p. superficialis in subgroup Am than in subgroups Dm and Mm (р&lt;0.001). Similar differences were found out for the thigh muscle (р&lt;0.05).

Investigation 0f Beef Brisket Palatability from Three USDA Quality Grades

The objective of this study was to investigate differences in smoked beef brisket palatability from 3 USDA quality grades (USDA Prime, average [middle 1/3] Choice, and Select). Briskets (n = 54; 18 per quality grade) were seasoned with a blend of 1:1 coarse salt/black pepper, and then cooked in a smoker to a final internal temperature of 93°C for approximately 6 to 7 h. For sensory analysis, briskets were separated into point (pectoralis superficialis) and flat (pectoralis profundus) portions and then sliced perpendicular to the muscle fibers. Consumer panelists (N = 360) evaluated palatability traits, acceptability of each trait, and willingness to pay (WTP). An interaction between quality grade and muscle was observed (P ≤ 0.03) for all palatability traits, proportion of acceptable samples, and WTP. Consumers could not distinguish among quality grades of the point portions for tenderness, juiciness, flavor liking, and overall liking (P > 0.05). Point samples, regardless of quality grade, were scored greater (P < 0.05) than Prime flat samples for all palatability traits. Choice and Select flat samples were scored lesser (P < 0.05) than all other treatment combinations for tenderness, flavor liking, and overall liking. In alignment with palatability traits, consumers’ WTP was greatest for point portions, regardless of quality grade (P < 0.05), followed by Prime flat portions. Choice and Select flat portions had the lowest WTP (P < 0.05). Consumer acceptability of cooked beef brisket generally followed similar trends as palatability scores. Quality grade had no effect on the eating quality of the point portions of smoked briskets, and point portions received superior palatability scores to flat portions. Prime flat portions had greater eating quality compared to that of Choice and Select flat portions, and consumers had greater WTP for what they perceived as superior eating quality.

Seasonal muscle ultrastructure plasticity and resistance of muscle structural changes during temperature increases in resident black-capped chickadees (Poecile atricapillus) and rock pigeons (Columba livia)

Resident birds in temperate zones respond to seasonally fluctuating temperatures by adjusting their physiology, such as changes in basal metabolic rate or peak metabolic rate during cold exposure, or altering their organ sizes, so as to match the thermogenic requirements of their current environment. Climate change is predicted to cause increases in the frequency of heat and cold wave events, which could increase the likelihood that birds will face an environmental mismatch. Here, we examined seasonality and the effects of acute and chronic heat shock to 33°C and subsequent recovery from heat shock on the ultrastructure of the superficial pectoralis muscle fiber diameter, myonuclear domain (MND) and capillary density in two temperate bird species of differing body mass, the black-capped chickadee (Poecile atricapillus) and the rock pigeon (Columba livia). We found that muscle fiber ultrastructure did not change with heat treatment. However, in black-capped chickadees, there was a significant increase in fiber diameter in spring phenotype birds compared with summer phenotype birds. In rock pigeons, we saw no differences in fiber diameter across seasons. Capillary density did not change as a function of fiber diameter in black-capped chickadees, but did change seasonally, as did MND. Across seasons, as fiber diameter decreased, capillary density increased in the pectoralis muscle of rock pigeons. For both species in this study, we found that as fiber diameter increased, so did MND. Our findings imply that these two temperate birds employ different muscular growth strategies that may be metabolically beneficial to each.

Digestive tract morphometry and breast muscle microstructure in spent breeder ducks maintainedin a conservation programme of genetic resources

Abstract. The objective of this study was to compare three genetic groups of ducks: P9 (French Pekin), K2 (bred from wild mallards – Anas platyrhynchos L. and Pekin duck), and KhO1 (hybrid of Khaki Campbell drake and Orpington Fauve duck) after two breeding seasons for body weight and length, length of intestine and its segments, percentage of other internal organs, and breast muscle microstructure. The study used 60 ducks, 20 birds (10 males and 10 females) from each genetic group. At 110 weeks of age, P9 ducks exhibited significantly (p&lt;0.05) greater body weight and length, and length of intestine and its segments (except for colon length) compared to K2 and KhO1 ducks. KhO1 ducks had significantly shorter jejunum and ileum compared to K2 birds. The lighter K2 and KhO1 ducks had significantly greater relative length of intestine and its segments. In P9 ducks, liver, heart, and gizzard were heavier and spleen percentage in body weight significantly lower than in K2 and KhO1 birds. KhO1 ducks had a significantly higher percentage of proventriculus compared to the other duck groups. The different genetic origins of the ducks had no effect on microstructural characteristics of m. pectoralis superficialis except for perimysium and endomysium thickness. Our study provided information about differences in the digestive tract morphometry and breast muscle microstructure of ducks from three genetic groups after two reproductive seasons, which are maintained in a conservation programme of genetic resources in Poland.

MEAT COMPOSITION AND QUALITY IN MALE JAPANESE QUAILS FROM HEAVY PHARAOH LINE

At 35 days of age, meat quality analysis was done as well as proximate analysis of breast and thigh muscles of 72 male quails from heavy Pharaoh line. Lightness values (L*) depended both on the time of post mortem analysis and of topographic site – lateral or medial muscle surface of the pectoral muscle. The L* value of lateral M. pectoralis superficialis (MPS) was higher. Redness and yellowness of meat increased proportionally to post mortem ageing, with peak values on the 24th post mortem hour. The chroma was more expressed on the medial MPS surface. With regard to determination of a common index of meat colour based on CIE L*a*b* coordinates, we propose the calculation of Meat Colour Index (MCI) according to the formula: MCI = (L* - C*). The meat of Japanese quails had high protein and low fat content. Gross energy of breast meat was within 5.03 - 6.13 MJ*kg-1, and that of thigh meat between 4.90 and 5.75 MJ*kg-1. The processing mode of carcasses by removing the skin made quail meat an exceptionally dietetic product with fat content &lt; 3%.

The Effects of Different Amount of Protein and Vitamin e Supplementation in Rations on Lipid and Antioxidant Metabolism of Broilers Exposed to Heat Stress

ABStRACt Heat stress, causes economic losses and has negative effects on both broiler husbandry and animal welfare. Nutritional strategies are applied for minimizing the negative effects of heat stress. In the present study, at the finishing period (24-39 days of age) of heat stress, the effects of diet involving 21% and 19% proteins and vitamin E on lipid metabolism and antioxidant mechanism of action, aimed to be identified. This study was carried out in six groups as: HPC (24 o C heat + 21% crude protein (CP)), HPS (34 o C heat + 21% CP), LPC (24 o C heat + 19% CP), LPS (34 o C heat + 19% CP), HPSVE (34 o C heat + 21% CP + Vitamin E) and LPSVE (34 o C heat + 19% CP + vitamin E) groups. Superficial pectoral muscles (breast) and liver tissues were used for oxidative stress and antioxidant defence determinations. Triglyceride and cholesterol levels have also been determined in blood serums. During the research, it is found that heat stress increased serum triglyceride and cholesterol levels, where Vitamin E has recovered triglyceride levels limitedly and cholesterol levels significantly. It is also observed that the adverse effect of high temperature was directly related to oxidative stress. Protein levels and vitamin supplementation relatively ameliorated these adverse effects, suggesting the tissue specificity. Consequently, the importance of feeding strategies such as the presence of Vitamin E and protein ratios on broiler nutrition in heat stress was established.

Lauric acid as feed additive - An approach to reducing Campylobacter spp. in broiler meat.

The increasing prevalence of Campylobacter spp. within broiler populations is a major problem for food safety and consumer protection worldwide. In vitro studies could already demonstrate that Campylobacter spp. are susceptible to lauric acid. The purpose of this study was to examine in vivo the influence of lauric acid as a feed additive on slaughter parameters, muscle fatty acid profile, meat quality traits and the reduction of Campylobacter coli in inoculated meat of Ross 308 (R308) and Hubbard JA 757 (HJA) broilers in three independent trials (n = 3). Although slaughter parameters did not show any significant differences, the fatty acid profile of both breeds revealed significantly higher lauric acid concentrations (P < 0.0001) in the Musculus pectoralis superficialis of treated broilers. Comparing both tested breeds, R308 test broilers had significantly higher lauric acid concentrations than HJA test broilers (P < 0.0001), indicating a higher conversion rate in those animals. The meat quality traits showed no differences in the R308 breed (P > 0.05), but HJA test broilers had higher values for drip loss, electrical conductivity, CIE color values L* and b*, and lower pH values. The inoculation trials of R308 showed that initial bacterial loads of 5.9 log10 cfu/g were reduced during six days of storage (4°C) to approximately 4.3 log10 cfu/g in the control groups compared to 3.5 log10 cfu/g in the treatment groups (P = 0.0295), which could be due to antimicrobial effects of lauric acid within the muscle. This study therefore suggests that lauric acid as a feed additive has the potential to improve food safety by reducing the numbers of Campylobacter coli in broiler meat. However, this effect seems to be dependent on the breed determining the feed intake capacity, the fat deposition and therefore the ability to incorporate lauric acid in the muscle.

Wybrane cechy mikrostruktury miesnia piersiowego powierzchownego oraz podstawowe wartosci uzytkowosci rzeznej gesi mieszanc�w

The aim of study was to determine of basic values slaughter meat production and histological parameters of pectoral muscle in quadruple 24 weeks old crossbred geese. The hybrids produced using Graylag, White Koluda and Slovakian geese. The geese were divided to 4 groups differing crosses scheme. The body weight before slaughter was in the range from 4,752 g to 4,921 g, weight of carcass with neck from 3,101 g to 3,175 g and weight of breast muscles from 649 g to 698 g. Histological analysis of pectoral muscle showed that diameters of white fibers (αW) was in the range from 43 μm to 46 μm, red fibers (βR) from 19.4 μm to 22.1 μm. The percentage share of αW muscle fibers was in the range from 25.3% to 28.9%, βR fibers from 71.1% to 74.7%. The number of muscle fibers per unit area was in the range from 256 to 316 and intramuscular fat content from 3.9% to 6.7%. The results of evaluation of microstructural traits of musculus pectoralis superficialis and meat production parameters suggest that the breast muscles of the crossbred geese are raw material of high quality. The quadruple crossbred geese with graylag geese it is an alternative for production of high-quality meat.

Effect of extruded flaxseed enriched diet on physico-chemical and sensory characteristics of broiler meat

The aim of this experiment was to examine the effect of the addition of extruded flaxseed to chicken feed on physico-chemical and sensory characteristics of breast and leg-thigh meat. The basic chemical composition, pH value, instrumental colour and sensory characteristics of white (breast) and dark meat (leg-thigh) were examined by feeding two groups (both comprising males and females) of 500 Ross 308 hybrid line chickens by standard feed (control group) and with the addition of 6% of extruded flaxseed mixture (experimental group). Instrumental characteristics of colour were changed, especially in white meat. Both breast muscles of male broilers were significantly lighter, but a* values were significantly lower in m. pectoralis profundus and b* values higher in m. pectoralis superficialis of both genders. In dark meat, a* values were significantly lower in the meat of males, while b* values were higher in the meat of females. The addition of extruded flaxseed to chicken feed did not led to significant changes in the sensory characteristics of meat.

GROSS ANATOMY AND SURGICAL APPROACH TO THE HUMERAL SHAFT IN GIANT ANTEATER (MYRMECOPHAGA TRIDACTYLA)

Anteater forelimbs are distinguished morphologically from domestic animals, especially due to their unique movement and their natural habits. A knowledge of the pectoral limb anatomy and the proper surgical approach are fundamental to success in osteosynthesis and other surgeries. This study aimed to describe the muscles and neurovascular structures of the pectoral limb and the surgical approach to the humeral shaft of the giant anteater ( Myrmecophaga tridactyla ). Dissections of the forelimbs of seven cadavers were performed to identify the major muscles and neurovascular structures. Three of these animals' contralateral forearms were used to simulate the surgical approach to the humeral shaft. Some specific characteristics of the muscle morphology were biceps muscle had two heads, triceps muscle had three heads, and there was an olecranon-epicondylar muscle. To expose the shaft of the humerus, it was necessary to incise the superficial pectoral muscle and separate the heads of the biceps muscle. Due to the anatomical characteristics of the humerus, the craniomedial approach was the most appropriate because it accommodated the anatomical peculiarities of the giant anteater.

Carcass composition and quality of meat from Pekin ducks finished on diets with varying levels of whole wheat grain

The aim of the research was to determine the effect of replacing part of a commercial feed mixture with whole wheat grain on the bodyweight, carcass composition and meat quality of Pekin ducks. A total of 160 1-day-old sexed SM3 Heavy hybrid ducks were used in the study. Two diets were given during the rearing period (36–49 days): (1) a complete commercial diet ad libitum, and (2) restricted amounts of a commercial diet (85%) and whole wheat grain (15%). Each treatment consisted of four replications of 20 birds each. Adding whole wheat grain to the ration resulted in no significant (P &gt; 0.05) changes in bodyweight (3475.8 g), feed conversion ratio (0–49 days, 2.50 kg DM intake/kg liveweight gain) dressing percentage (70.1%) and carcass tissue composition in ducks at 49 days of age. Breast muscle (superficial pectoral muscle) from ducks fed the commercial diet and whole wheat grain was significantly (P &lt; 0.05) lighter in colour (L* = 39.9 vs 38.0) and a deeper yellow colour (b* = 1.7 vs 0.8), as compared with that from birds receiving the complete commercial diet alone. Breast muscle (superficial pectoral muscle and profound pectoral muscle) also had significantly (P &lt; 0.05) higher threonine (3.9 vs 5.1 g/100 g DM) and valine content (4.0 vs 5.0 g/100 g DM). However, leg muscle (thigh and drumstick muscles) from experimental ducks had a significantly (P &lt; 0.05) lower content of crude fat (5.1% vs 4.2%) and collagen (1.5% vs. 1.1%), as well as less glutamic acid (14.2 vs 12.5), proline (3.5 vs 3.2), alanine (3.0 vs 2.5) and arginine (6.5 vs 5.6 g/100 g DM), as compared with the control birds.