Muscle Of Broiler Chickens Research Articles

Acute toxicity of boric acid on energy metabolism of the breast muscle in broiler chickens

Short-and long-term oral exposures to boric acid (BA) in laboratory animals and birds caused toxic effects. However, the toxicity data on adult poultry skeletal muscles of BA was not documented with metabolic studies. Livability, weight gain, and feed conversion might be adversely affected in broilers as a result of changes in energy metabolism. Therefore, this study was conducted to investigate the influences of acute BA doses on energy metabolism of chick pectoral muscle (PM). Chicks were fed by giving the aqueous solutions supplemented with BA (0, 0.27, 0.54, 1.08, 1.35, 2.25, 3.375 and 4.5 mmol B/kg b.wt.). Breast muscle samples were taken at 24, 48 and 72 h and analyzed histochemically, ultrastructurally and biochemically. Data collected in these analyses indicated that consumption of diets containing up to 2.25 mmol B/kg at 24, 48 and 72h was not detrimental to broiler PM. However, 3.375 mmol B/kg b.wt. (at 24 h) and 4.5 mmol B/kg b.wt. (at 24 and 48 h) caused decreased metabolite concentrations (glucose, glycogen, lactate and ATP) in muscle fibers (Type IIB). Subsarcolemmal (SS) mitochondria and intermyofibrillar (IM) mitochondrial damage (cristae dissolution) were also observed by toxic effect of BA (4.5 mmol B/kg b.wt.). These observations proved that BA at the high doses (3.375 and 4.5 mmol B/kg b.wt.) causes to altered energy metabolism in Type IIB as dependent on time. Based on these results we think that energy protection in muscle against BA toxicity will be the most important study subject. Thus, high BA doses will not have detrimental effects on broiler performance.

Effect of magnesium on reactive oxygen species production in the thigh muscles of broiler chickens

1. The objective of the present study was to investigate the effect of magnesium (Mg) on reactive oxygen species (ROS) production in the thigh muscles of broiler chickens. A total of 96 1-d-old male Arbor Acre broiler chickens were randomly allocated into two groups, fed either on low-Mg or control diets containing about 1·2 g/kg or 2·4 g Mg/kg dry matter. 2. The low-Mg diet significantly increased malondialdehyde (MDA) concentration and decreased glutathione (GSH) in the thigh muscles of broiler chickens. ROS production in the thigh muscle homogenate was significantly higher in the low-Mg group than in the control group. Compared with the control, muscle Mg concentration of broiler chickens from the low-Mg group decreased by 9·5%. 3. Complex II and III activities of the mitochondrial electron transport chain in broilers on low-Mg diet increased by 23 and 35%, respectively. Significant negative correlations between ROS production and the activities of mitochondrial electron transport chain (ETC) complexes were observed. 4. The low-Mg diet did not influence contents of iron (Fe) or calcium (Ca) in the thigh muscles of broiler chickens and did not influence unsaturated fatty acid composition (except C18:2) in the thigh muscles. 5. A low-Mg diet decreased Mg concentration in the thigh muscles of broiler chickens and then induced higher activities of mitochondrial ETC, consequently increasing ROS production. These results suggest that Mg modulates the oxidation–anti-oxidation system of the thigh muscles at least partly through affecting ROS production.

Altered development and protein metabolism in skeletal muscles of broiler chickens (Gallus gallus domesticus) by corticosterone

Two trials were conducted to investigate the effect of corticosterone (CORT) on protein metabolism and the amino acid composition in muscle tissues of broiler chickens (Gallus gallus domesticus). In Trial 1, two groups of 30 broiler chickens were subjected to control or CORT treatment (30 mg/kg diet) from 28 to 39 days of age. In Trial 2, three groups of chickens of 28 days of age were randomly subjected to one of the following treatments for 7 days: CORT (30 mg/kg diet), pair-fed (maintaining the same feed intake as CORT treatment) and control treatments. The body mass gain and feed efficiency was significantly decreased by CORT treatment, while the food intake was decreased. The breast and thigh masses (% body mass) were significantly suppressed by CORT treatment, while the abdominal fat and liver masses (%) were obviously increased. The plasma levels of glucose, urate and total amino acid were significantly elevated by CORT treatment. The capacity for protein synthesis, estimated by RNA:protein ratio, were significantly suppressed by CORT in M. pectoralis major and M. biceps femoris. The 3-methylhistidine concentrations were significantly increased in both M. pectoralis major and M. biceps femoris of CORT chickens, compared to control but not the pair-fed chickens. The amino acid composition of M. pectoralis major and M. biceps femoris was not significantly affected by CORT treatment. In conclusion, the arrested growth in skeletal muscles induced by CORT administration has tissue specificity. The CORT treatment retards the growth of skeletal muscle by suppressed protein synthesis and augmented protein catabolism.

Glycogen debranching enzyme and some other factors relating to post‐mortem pH decrease in poultry muscles

AbstractThe objective of this study was to investigate the activity of glycogen debranching enzyme (GDE, EC 3.2.1.68) in chicken pectoralis superficialis (PS) and quadriceps femoris (QF) muscle post‐mortem. In addition, some other factors relating to pH decrease, such as the activity of glycogen phosphorylase (EC 2.4.1.1) and glycolytic potential were studied. Enzyme activities, glycogen content and lactate content were measured in Ross breed broiler chicken muscles obtained 25 min after stunning. An interesting discrepancy in the activities of the two glycogen degrading enzymes, GDE and phosphorylase, between muscles was found. In light PS muscle, phosphorylase activity was higher (P < 0.001), but GDE activity was lower (P < 0.001) than in dark QF muscle. Buffering capacity and glycolytic potential were higher in PS muscle than in QF muscle. The possible need for high buffering capacity and low GDE activity in PS muscle to protect living muscle from rapid pH decrease was discussed. GDE, together with glycolytic potential, accounted for 40% of the variation in ultimate pH in QF muscle and 61% in PS muscle. Considering the low activity of GDE together with the high activity of phosphorylase found in both muscles, the results of the present study support the hypothesis that GDE may restrict the rate of glycogen degradation. Copyright © 2006 Society of Chemical Industry

Morfologia das fibras musculares esqueléticas de frangos de corte de diferentes linhagens criados em sistemas de confinamento e semiconfinamento

Avaliou-se o efeito da linhagem, do sistema de criação e do sexo sobre o peso vivo, o rendimento de carcaça e de pernas e os aspectos morfológicos das fibras musculares esqueléticas do músculo flexor longo do hálux de frangos de corte. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 4 x 2 x 2, ou seja, quatro linhagens (Ross-308, Pescoço Pelado Label Rouge, Caipirinha e Paraíso Pedrês), dois sistemas de criação (confinamento e semiconfinamento) e dois sexos, com duas repetições por tratamento, sendo que cada ave retirada ao acaso aos 56 dias de idade foi considerada uma unidade experimental, totalizando 64 aves. A linhagem Ross apresentou maior peso vivo e maiores pesos de carcaça, de pernas, de carne de penas e do músculo flexor longo do hálux e maiores rendimentos de carcaça e de carnes de pernas que as outras linhagens. A maior massa muscular das aves selecionadas para alta taxa de crescimento está relacionada ao aumento na área dos três tipos de fibras musculares (SO, FOG e FG). Machos apresentaram maior massa muscular e musculatura mais glicolítica que fêmeas. O sistema de semiconfinamento alterou a composição de fibras musculares esqueléticas dos machos, tornando-a mais oxidativa, porém, esse efeito não foi observado nas fêmeas.

Effects of Supplementary Copper Chelates in the Form of Methionine, Chitosan and Yeast on the Performance of Broilers

An experiment was conducted to investigate the effects of supplemental copper (Cu) chelates (methionine, chitosan and yeast) on the performance, nutrient digestibility, serum IgG level, gizzard erosion, Cu content in the liver and excreta and the level of total cholesterol in breast muscle and serum of broiler chickens. Two hundred and forty hatched broiler chickens (Ross 208) were assigned to 4 treatments: control, 100 ppm Cu in methionine chelate (Met-Cu), 100 ppm Cu in chitosan chelate (Chitosan-Cu) and 100 ppm Cu in yeast chelate (Yeast-Cu). Each treatment had six replicates of 10 (5 males+5 females) birds each. Weight gain and feed intake tended to be higher in Cu chelate treatments than the control; weight gain was significantly higher in the Met-Cu chelate treatment and feed intake was significantly higher in the Yeast -Cu chelate treatment than the control (p<0.05). Feed/gain was significantly different between treatments in which Met-Cu was lowest followed by the control, Chitosan-Cu and Yeast-Cu. DM availability was increased by Cu chelates among which chitosan-Cu showed the highest DM availability. Cu chelates supplementation tended to increase gizzard erosion index, and Cu content in the liver was highest in the Met-Cu treatment. Supplementation of Cu chelates tended to decrease total cholesterol level in breast muscle and serum but tended to increase the level of HDL in serum. It was concluded that dietary supplementation of 100 ppm Cu in chelates increased weight gain, feed intake and DM availability. Met-Cu was more effective than Chitosan-Cu or Yeast-Cu in improving productivity of broiler chickens.

Effects ofLactobacillusfeed supplementation on cholesterol, fat content and fatty acid composition of the liver, muscle and carcass of broiler chickens

An experiment was conducted to study the effects of feed supplementation with a mixture of Lactobacillus cultures ( LC) on cholesterol, fat and fatty acid composition in the liver, muscle and carcass of broiler chickens. One hundred and thirty- six, one- day- old male broiler chicks ( Avian- 43) were assigned randomly to two dietary treatments: ( i) a basal diet ( control), and ( ii) a basal diet + 0.1% LC. The cholesterol contents of the carcass and liver but not the muscle, were significantly ( P < 0.05) lower in LC- fed broilers. The fat contents of the liver, muscle and carcass were also significantly ( P < 0.05) lower in the LC- fed broilers when compared to the control broilers. Supplementation of LC in the broiler diets significantly ( P < 0.05) reduced the oleic acid ( C-18: 1) levels of the liver, muscle and carcass but the arachidonic acid ( C-20:4) level was significantly ( P < 0.05) increased in the liver only. Supplementation of LC also increased the total polyunsaturated fatty acids ( PUFA) in the liver. The results of the present study indicate that LC reduces the fat content of the liver, muscle and carcass of broiler chickens, but it has very little potential to modify the fatty acid composition.

The Effect of Feed and Temperature Regimen on Lipid Oxidation in Muscle of Broiler Chickens

The paper presents the effects of temperature and feed composition on the stability of lipids in breast and thigh muscles of COBB 500 meat hybrids. The chickens were reared in accordance with the technological procedure. The diet of experimental groups contained Proenergol in combination with Energol; the diet of control group chickens contained Proenergol and soybean oil. In the control groups and in half of the experimental groups, the temperature was reduced in agreement with the technological procedure, while it was kept at the constant level of 31 °C in other groups. The feeding continued up to the age of 42 days. The level of lipid oxidation was determined using malondialdehyde assays. No differences between individual groups of chickens were found in the breast muscle. In the thigh muscle, the introduction of Energol resulted in non-significant differences between the control and chickens kept in heat stress conditions. Negative correlation between lipid oxidation and live weight was established in control chickens fed soybean oil (p &lt; 0.05). This correlation was positive (p &lt; 0.05) in young male chicks fed Energol and kept at constantly increased temperature.

Cloning and gene expression of hexokinase I and II in the chicken skeletal muscle

ABSTRACTTo elucidate the distinctive regulatory mechanisms of glucose homeostasis in the skeletal muscles of broiler chickens, hexokinase (HK)I and HKII gene expressions were characterized by northern blot analysis. Chicken HKI and HKII full‐length cDNA sequences were identified and the deduced amino acid sequences were 87.4 and 85.9% identical to that of human HKI and HKII, respectively. Using reverse transcription‐polymerase chain reaction analysis, chicken HKI mRNA was detected in the skeletal muscle, brain, heart, kidney and testis. Chicken HKII mRNA was highly expressed in the skeletal muscle and heart, whereas a lower expression was observed in the liver, brain and kidney. Fasting for 48 h or refeeding for 24 h in chickens significantly increased the skeletal muscle HKI and HKII mRNA levels in contrast to unchanged or decreased expressions in mammals. The present findings suggest that HKI and HKII have a unique role in the glucose homeostasis regulatory mechanism of chicken skeletal muscles and their role in chickens is not similar to that in mammals.

Microstructure and thermal characteristics of Thai indigenous and broiler chicken muscles

The microstructure and thermal characteristics of Thai indigenous (Gallus domesticus) and broiler chicken (commercial line CP707) biceps femoris and pectoralis muscles were determined. Perimysium thicknesses were 14.2 microm for biceps femoris muscle and 7.10 microm for pectoralis muscle of indigenous chicken muscles, thicker than those of broiler muscles, which were 9.93 microm for biceps femoris muscle and 3.87 microm for pectoralis muscle (P < 0.05). Five endothermic peaks with peak transition temperatures (Tp) of 54.9, 61.7, 65.4, 70.6, and 76.1 degrees C were obtained for broiler pectoralis muscle, whereas only 3 endothermic peaks (Tp of 56.6, 62.6, and 74.9 degrees C) were obtained for broiler biceps femoris muscle. Thai indigenous biceps femoris and pectoralis muscles had endothermic peaks with Tp ranges of 53.5 to 54.8, 60.7 to 61.9, and 75.9 to 76.9 degrees C. The fiber diameters of Thai indigenous chicken muscles were greater (P < 0.05) than those of the broiler, 31.7 vs. 20.4 microm for biceps femoris muscle and 28.9 vs. 26.6 microm for pectoralis muscle, respectively. After cooking at 80 degrees C for 10 min, the fiber diameter of indigenous chicken muscles significantly decreased while those of the broiler significantly increased. The mean of sarcomere lengths of the raw muscles ranged from 1.56 to 1.64 microm and decreased to 0.92 to 1.32 microm (P < 0.001) for broiler muscles and 1.22 to 1.35 microm (P < 0.001) for indigenous chicken muscles after cooking. The perimysium and endomysium of broiler muscles melted after cooking at 80 degrees C, however, only slight disintegration was observed in these tissues in the indigenous chicken muscles.

Effect of heat treatment on changes in texture, structure and properties of Thai indigenous chicken muscle

Changes in texture, microstructure, colour and protein solubility of Thai indigenous and broiler chicken Pectoralis muscle stripes cooked at different temperatures were evaluated. The change in shear value of both chicken muscles was a significant increase from 50 to 80 °C but no change from 80 to 100 °C. A significant decrease in fibre diameter was obtained in samples heated to an internal temperature of 60 °C and the greatest shrinkage of sarcomeres was observed with internal temperatures of 70–100 and 80–100 °C for broiler and indigenous chicken muscles, respectively ( P < 0.05). Cooking losses of indigenous chicken muscles increased markedly in the temperature range 80–100 °C and were significantly higher than those of the broiler ( P < 0.001). With increasing temperature, from 50 to 70 °C, cooked chicken muscle became lighter and yellower. Relationships between changes in sarcomere length, fibre diameter, shear value, cooking loss and solubility of muscle proteins were evaluated. It was found that the solubility of muscle protein was very highly correlated with the texture of cooked broiler muscle while sarcomere length changes and collagen solubility were important factors influencing the cooking loss and texture of cooked indigenous chicken muscle.

Breed differences in the biochemical determinism of ultimate pH in breast muscles of broiler chickens--a key role of AMP deaminase?

The biochemical determinism of ultimate pH (pHu) was studied in the pectoralis muscle of broiler chickens. Thirty birds of 3 genetic types (a fast-growing standard (FG), a slow-growing French "Label Rouge" (SG), and a heavy line type (HL)) were kept under conventional breeding methods until the usual marketing age (6, 12, and 6 wk for FG, SG, and HL birds, respectively). The birds were divided into 3 different antemortem treatment groups: minimum stress, shackling for a longer time (2 min), and heat stress (exposure to 35 ° C for 3.5 h and shackling for 2 min before stunning). The birds were slaughtered on the same day. The pHu differed (P < 0.001) among the 3 genetic types, ranking as follows: FG (5.95+/-0.01) > HL (5.85+/-0.02) > SG (5.73+/-0.02). In SG and HL birds, pHu was strongly correlated with muscle glycogen content at slaughter (r = -0.74 and -0.82; P < 0.01 respectively), whereas this correlation was weak in FG birds. Regardless of genetic type, neither buffering capacity nor lactate accumulation significantly contributed to pHu variations (P > 0.05). The activity of adenosine monophosphate deaminase (AMPd) was significantly higher in FG chickens (0.98+/-0.31; P < 0.05) than in HL and SG birds (0.46+/-0.24 and 0.34+/-0.18, respectively). Significant correlations were found between AMPd activity, pHu, and glycolytic potential (GP) at slaughter (r = 0.34 and -.29; P < 0.01, respectively). Further research is needed to study in more detail the role of AMPd in the determinism of pHu, particularly in fast-growing broilers.

Tracing metabolic routes of feed ingredients in tissues of broiler chickens using stable isotopes

The present study aimed to quantify the proportion of 13 C from energy and protein feed ingredients that follow the metabolic routing of the liver and muscle in broiler chickens. A stable isotope of carbon technique was used that is based on the isotopic discrimination that occurs in the plants during the photosynthesis process. One-day-old male chicks were subjected to treatments based on free choice of energy and protein sources. Rice bran (R) and soybean meal (S), C3 plants, have higher isotopic ratios than corn (C), a C4 plant, and corn gluten meal (G). Choices were R+S, C+G, R+G, C+S, or R+C+G+S. A complete feed (CF) was a sixth treatment. Feed intake and BW were measured at 30 d of age, when liver and breast muscle were collected for isotopic analysis. Treatments affected the amount of feed intake and the choices of energy or protein sources. Complete feed had the largest intake, differing from the other treatments that had free-choice feeding. Final BW was a direct reflection of consumption by these birds in all treatments. The isotopic results indicated that the 13 C/12 C ratio was generally higher in breast muscle than in liver, probably because of higher protein content. Moreover, in the liver, the proportion of 13 C retained from the energy ingredient was greater than the proportion from the protein ingredient. That is in contrast to muscle, where the proportion of 13 C retained from the protein ingredient was greater than from the energy ingredient that was self-selected.

Species and muscle differences in L-carnitine levels in skeletal muscles based on a new simple assay

We have adapted the enzymatic method [Biochemical and Biophysical Research Communications 176 (3) (1991) 1617] for the safe and rapid assay of L-carnitine (L-CA) in skeletal muscle using a microplate reader. The concentration of L-CA in fresh semitendinosus muscle from broiler chicken, pig, beef cattle, deer, horse and goat muscle were 0.69, 1.09, 1.86–3.57, 4.57, 4.95 and 11.36 μmol/g wet weight, respectively. The animals which had higher concentration of L-CA, also had the highest amounts of myoglobin as an index to the redness of the muscle. Furthermore, we investigated this relationship between white muscle, M. pectoralis profundus, and red muscle, M. soleus, in laying hens. The L-CA and myoglobin concentration in red muscle were significantly higher than those in white muscle ( p<0.01). These findings suggest that L-CA concentration in muscle is related to oxygen metabolism and to myofiber types.

Simultaneous quantification of ciprofloxacin, enrofloxacin and balofloxacin in broiler chicken muscle

La presencia de residuos de medicamentos veterinarios en alimentos es una preocupaci¨®n creciente para consumidores y para entes reguladores internacionales. Los limites m¨¢ximos de residuos (LMR) en tejidos comestibles de origen animal son establecidos a partir del desarrollo de m¨¦todos anal¨aticos. Se efectu¨® la validaci¨®n del m¨¦todo de detecci¨®n de ciprofloxacina (CFX), enrofloxacina (EFX) y balofloxacina (BFX) en m¨²sculo de pollos parrilleros por extracci¨®n en fase liquida y determinaci¨®n simult¨¢nea por cromatograf¨aa l¨aquida de alta presi¨®n (HPLC). Las muestras se homogenizaron y se adicionaron inicialmente con los antimicrobianos, luego se extrajeron con diclorometano dos veces. Estas fluoroquinolonas fueron cuantificadas por HPLC, detecci¨®n por fluorescencia a 295 nm de excitaci¨®n y 500 nm de emisi¨®n. El ensayo fue linear entre 0.00 l Y 0.1 ¦Ig/g. Los l¨amites de cuantificaci¨®n fueron 0.0119 ¦Ig/g para EFX, 0.0436 ¦Ig/g BFX y 0.0557 ¦Ig/g para CFX. Los ¨andices de recuperabilidad de los metabolitos en m¨²sculo, entre 0.0 l y 0.1 ¦Ig/g, calculados comparando las muestras inicialmente adicionadas contra muestras de m¨²sculo con incorporaci¨®n de los antimicrobianos luego del procesado, promediaron los 77.47% para EFX, 87.7% para CFX y 96.67% para BFX. Los extractos eluidos no presentaron interferencias de la matriz biol¨®gica y tuvieron buena resoluci¨®n de los analitos en los cromatogramas. Los LMR son establecidos a partir de los factores de riesgo, ensayos toxicol¨®gicos pertinentes y m¨¦todos de detecci¨®n desarrollados y validados, los cuales deben ser factibles de implementaci¨®n. Este es un m¨¦todo simple y econ¨®mico para cuantificar la presencia simult¨¢nea de CFX, EFX y BFX en m¨²sculo de pollo.

Composition, Color, and Texture of Thai Indigenous and Broiler Chicken Muscles

Chemical compositions and physical properties of mixed-sex Thai indigenous (Gallus domesticus) and broiler (commercial breed, CP707) chicken biceps femoris and pectoralis muscles were determined. Indigenous chicken muscles contained higher protein contents but lower fat and ash contents compared to broiler muscles (P < 0.001). The amino acid profile of the indigenous chicken muscles was similar to that of the broiler muscles except they were slightly richer in glutamic acid (P < 0.05). The indigenous chicken muscles contained more saturated and less polyunsaturated fatty acids than the broiler muscles. There were no differences in the monounsaturated fatty acid contents between the breeds. The total collagen contents of indigenous pectoralis and biceps femoris muscles were 5.09 and 12.85 mg/g, respectively, which were higher than those found in broiler pectoralis (3.86 mg/g) and biceps femoris muscles (8.70 mg/g) (P < 0.001). Soluble collagen contents were lower for indigenous pectoralis and biceps femoris muscles, 22.16 vs. 31.38% and 26.06 vs. 33.87%, respectively. The CIE system values of lightness (L*), redness (a*), and yellowness (b*) of indigenous chicken muscles were higher than those of broiler muscles. The shear values of indigenous chicken muscles either raw or cooked were higher than those of broiler muscles (P < 0.05). After cooking, the shear values decreased for broiler biceps femoris and pectoralis muscles (P < 0.05), whereas no change was observed for indigenous chicken biceps femoris muscle (P > 0.05). Shear values increased for indigenous chicken pectoralis muscle (P < 0.05).

Dietary n-3 and n-6 fatty acids alter avian metabolism: molecular-species composition of breast-muscle phospholipids.

The effects of diets high in n-3 polyunsaturated fatty acids (PUFA; provided by fish oil), n-6 PUFA (sunflower oil) or in more-saturated fatty acids (tallow) on the distribution of subclasses of choline phospholipids (PC) and ethanolamine phospholipids (PE) from the breast muscle of broiler chickens were examined. Supplementation with the different fatty acids had no effect on the distribution of phospholipid subclasses. Feeding sunflower oil or tallow gave a molecular-species profile similar in both fatty acid subtype and proportion. In the diacyl PC phospholipids, 16 : 0-18 : 1n-9 and 16 : 0-18 : 2n-6 accounted for approximately 60 % of the total molecular species, whereas for the alkylenyl PC the predominant species were 16 : 0-18 : 1n-9 and 16 : 0-20 : 4n-6. Of the diacyl PE the dominant species was 18 : 0-20 : 4n-6 which accounted for 50 % of the molecular species, and of the alkylenyl PE the dominant species were 16 : 0-18 : 1n-9, 16 : 0-20 : 4n-6 and 18 : 0-20 : 4n-6. Supplementation with fish oil significantly increased levels of both eicosapentaenoic acid (20 : 5n-3) and docosahexaenoic acid (22 : 6n-3) in PC and PE when compared with either sunflower oil or tallow supplementation. The increase in the n-3 PUFA incorporation was associated with a corresponding decrease in the proportion of arachidonic acid (20 : 4n-6) in both PC and PE. Different dietary fats induce different patterns of fatty acid incorporation and substitution in the sn-2 position of the diacyl and alkylenyl PC and PE of avian breast muscle, and this finding is indicative of selective acyl remodelling in these two phospholipids.

Dietaryn-3 andn-6 fatty acids alter avian metabolism: molecular-species composition of breast-muscle phospholipids

The effects of diets high inn-3 polyunsaturated fatty acids (PUFA; provided by fish oil),n-6 PUFA (sunflower oil) or in more-saturated fatty acids (tallow) on the distribution of subclasses of choline phospholipids (PC) and ethanolamine phospholipids (PE) from the breast muscle of broiler chickens were examined. Supplementation with the different fatty acids had no effect on the distribution of phospholipid subclasses. Feeding sunflower oil or tallow gave a molecular-species profile similar in both fatty acid subtype and proportion. In the diacyl PC phospholipids, 16: 0–18: 1n-9 and 16: 0–18: 2n-6 accounted for approximately 60 % of the total molecular species, whereas for the alkylenyl PC the predominant species were 16: 0–18: 1n-9 and 16: 0–20: 4n-6. Of the diacyl PE the dominant species was 18: 0–20: 4n-6 which accounted for 50 % of the molecular species, and of the alkylenyl PE the dominant species were 16: 0–18: 1n-9, 16: 0–20: 4n-6 and 18: 0–20: 4n-6. Supplementation with fish oil significantly increased levels of both eicosapentaenoic acid (20: 5n-3) and docosahexaenoic acid (22: 6n-3) in PC and PE when compared with either sunflower oil or tallow supplementation. The increase in then-3 PUFA incorporation was associated with a corresponding decrease in the proportion of arachidonic acid (20: 4n-6) in both PC and PE. Different dietary fats induce different patterns of fatty acid incorporation and substitution in thesn-2 position of the diacyl and alkylenyl PC and PE of avian breast muscle, and this finding is indicative of selective acyl remodelling in these two phospholipids.

Effect of dietary fat on fatty acid composition of lipids from breast muscle and abdominal fat of broiler chickens

Effect of dietary fat on fatty acid composition of lipids from breast muscle and abdominal fat of broiler chickens

Effects of dietary Spirulina on meat colour in muscle of broiler chickens

1. The present study was undertaken to determine the effects of dietary spirulina on growth performance and pigmentation in the muscle of growing broiler chickens and to examine the possibility that zeaxanthin in spirulina may affect yellow colour development in the meat. 2. Twenty-four, 21-d-old, male broiler chicks were fed an experimental diet containing spirulina at 0, 40, or 80 g/ kg for 16 d. No significant differences among treatments were observed in body weights, nor weights or yields (as a percentage of body weight) for any of the selected traits, including liver, abdominal fat, kidney and Pectoralis profundus . 3. Spectrocolourimetric analyses revealed that the redness of Pectoralis superficialis, profundus and Sartorius muscles reached a maximum in chicks fed the 40 g/kg spirulina diet, while the yellowness of all fillets, including the Semitendinosus muscle, increased in a sub-linear fashion with increased spirulina in the diet. The overall correlation between the yellowness and zeaxanthin content in the Pectoralis muscle was significant. 4. This study provides the first conclusive evidence that dietary spirulina influences both the yellowness and redness of broiler flesh and that the increments in yellowness with dietary spirulina content may possibly be reflected in the common yellow pigment related to the accumulation of zeaxanthin within the flesh.