Pigeon Muscle Research Articles

Chemometric−Assisted QuEChERS Method for Multiresidue Analysis of Veterinary Drugs in Pigeon Muscle by LC-MS/MS

Chemometric−Assisted QuEChERS Method for Multiresidue Analysis of Veterinary Drugs in Pigeon Muscle by LC-MS/MS

Analysis of mRNA and lncRNA Expression Profiles of Breast Muscle during Pigeon (Columbalivia) Development.

The breast muscle is essential for flight and determines the meat yield and quality of the meat type in pigeons. At present, studies about long non-coding RNA (lncRNA) expression profiles in skeletal muscles across the postnatal development of pigeons have not been reported. Here, we used transcriptome sequencing to examine the White-King pigeon breast muscle at four different ages (1 day, 14 days, 28 days, and 2 years old). We identified 12,918 mRNAs and 9158 lncRNAs (5492 known lncRNAs and 3666 novel lncRNAs) in the breast muscle, and 7352 mRNAs and 4494 lncRNAs were differentially expressed in the process of development. We found that highly expressed mRNAs were mainly related to cell-basic and muscle-specific functions. Differential expression and time-series analysis showed that differentially expressed genes were primarily associated with muscle development and functions, blood vessel development, cell cycle, and energy metabolism. To further predict the possible role of lncRNAs, we also conducted the WGCNA and trans/cis analyses. We found that differentially expressed lncRNAs such as lncRNA-LOC102093252, lncRNA-G12653, lncRNA-LOC110357465, lncRNA-G14790, and lncRNA-LOC110360188 might respectively target UBE2B, Pax7, AGTR2, HDAC1, Sox8 and participate in the development of the muscle. Our study provides a valuable resource for studying the lncRNAs and mRNAs of pigeon muscles and for improving the understanding of molecular mechanisms in muscle development.

Safety of an Intravenous Formulation of Voriconazole as an Intramuscular Injection in Pigeons (Columba livia f. domestica).

Aspergillosis is a common disease in birds. Currently, avian aspergillosis is treated with voriconazole administered orally, although intramuscular (IM) administration increases bioavailability and is more effective in treating generalized aspergillosis. The objective of this study was to evaluate the safety of the intravenous formulation of voriconazole as an IM injection in the pectoral muscles of pigeons (Columba livia f. domestica) as a model for other avian species. Sixteen healthy pigeons received IM injections of voriconazole (12.5 mg/kg) and sterile saline in the right and left pectoral muscles, respectively, twice a day for 7 days. Additionally, 4 birds acted as controls (no injections). Eight birds in the treatment group and 2 of the control pigeons were humanely euthanized 1 day (group 1) and 14 days (group 2) after the final injection. Hematologic and plasma biochemistry panels were performed prior to the birds being euthanized. Gross and histopathological evaluations of the pectoral muscles were completed postmortem. Statistical analysis revealed significant differences in multiple parameters, including aspartate aminotransferase and lactate dehydrogenase, but all biochemical analytes remained within the reference intervals for the species. The group 1 birds had advanced gross and histopathological pectoral muscle lesions associated with the voriconazole injections compared with the contralateral side, the group 2 birds, and the negative controls. After 14 days, the pectoral muscles did not reveal any gross or histopathological changes associated with the voriconazole or sterile saline injections. These results indicate that the intravenous formulation is safe for IM use twice per day for 1 week in pigeons. Further investigation is needed to extrapolate these findings to other avian species and to evaluate the roles of longer treatment periods and higher doses of voriconazole.

Transcriptome Analysis of Differentially Expressed mRNA Related to Pigeon Muscle Development.

Simple SummaryThe growth and development of skeletal muscle determine the meat production performance of pigeons and are regulated by complex gene networks. To explore the genes involved in regulating the growth and development of pigeon skeletal muscle, RNA sequencing (RNA−seq) was used to characterise gene expression profiles during the development and growth of pigeon breast muscle and identify differentially expressed genes (DEGs) among different stages. This study expanded the diversity of pigeon mRNA, and it was helpful to understand the role of mRNA in pigeon muscle development and growth.The mechanisms behind the gene expression and regulation that modulate the development and growth of pigeon skeletal muscle remain largely unknown. In this study, we performed gene expression analysis on skeletal muscle samples at different developmental and growth stages using RNA sequencing (RNA−Seq). The differentially expressed genes (DEGs) were identified using edgeR software. Weighted gene co−expression network analysis (WGCNA) was used to identify the gene modules related to the growth and development of pigeon skeletal muscle based on DEGs. A total of 11,311 DEGs were identified. WGCNA aggregated 11,311 DEGs into 12 modules. Black and brown modules were significantly correlated with the 1st and 10th day of skeletal muscle growth, while turquoise and cyan modules were significantly correlated with the 8th and 13th days of skeletal muscle embryonic development. Four mRNA−mRNA regulatory networks corresponding to the four significant modules were constructed and visualised using Cytoscape software. Twenty candidate mRNAs were identified based on their connectivity degrees in the networks, including Abca8b, TCONS−00004461, VWF, OGDH, TGIF1, DKK3, Gfpt1 and RFC5, etc. A KEGG pathway enrichment analysis showed that many pathways were related to the growth and development of pigeon skeletal muscle, including PI3K/AKT/mTOR, AMPK, FAK, and thyroid hormone pathways. Five differentially expressed genes (LAST2, MYPN, DKK3, B4GALT6 and OGDH) in the network were selected, and their expression patterns were quantified by qRT−PCR. The results were consistent with our sequencing results. These findings could enhance our understanding of the gene expression and regulation in the development and growth of pigeon muscle.

Identification and expression pattern analysis of miRNAs in pectoral muscle during pigeon (Columba livia) development.

MicroRNAs (miRNAs) are a group of crucial regulators in the process of animal growth and development. However, little is known about the expression and function of miRNAs in pigeon muscles. To identify the miRNAs participating in the rapid development of pigeon pectoral muscles and quantitate their expression levels of pectoral muscles in different age stages, we performed miRNA transcriptome analysis in pigeon pectoral muscles by sequencing small RNAs over three different age stages (1-day old, 28 days old, and 2 years old). Dual-luciferase reporter assay was applied to validate the interaction between miRNA and its target gene. We identified 304 known miRNAs, 201 conserved miRNAs, and 86 novel miRNAs in pigeon pectoral muscles. 189 differentially expressed (DE) miRNAs were screened out during pigeon development. A short time-series expression miner (STEM) analysis indicated 89 DE miRNAs were significantly clustered in a progressively decreasing expression profile, and mainly enriched in biosynthesis-related GO categories and signaling pathways for MAPK and TGF-β. Dual-luciferase reporter assay indicated that a progressively down-regulated miRNA (miR-20b-5p) could directly target Krüppel-like factor 3 (KLF3) gene. To sum-up, our data expand the repertoire of pigeon miRNAs and enhance understanding of the mechanisms underlying rapid development in squabs.

Profile of Heavy Metals and Antioxidant Defense in the Muscle Tissues of Pigeons (Columba livia f. urbana) from Anthropogenically Transformed Areas in the Pomeranian Region (Northern Poland)

Pigeons can be successfully used as bioindicators of a contaminated environment. We studied the relationship between the functioning of the pro/antioxidant balance in muscle tissues (skeletal muscle and cardiac tissues) of pigeons (Columba livia f. urbana) living in areas with different levels of pollution (Pomeranian Voivodeship, Northern Poland). The current study demonstrated the impact of the environment with preferential high Pb contamination in soil and feathers of pigeons on the formation of adaptive redox mechanisms in muscle tissues. An increase in the intensity of lipid peroxidation (estimated by the TBARS level) accompanied by enhancement of the oxidative modification of proteins (aldehydic and ketonic derivatives) and an important decrease in the activity of antioxidant enzymes (SOD, CAT, and GR) in pigeon muscle tissue was observed. These changes in enzyme activities were dependent on the type of muscle tissue (skeletal muscle and cardiac tissues). Our results confirm the concept of the recalculation of the De Ritis ratio (AsAT/AlAT) in both types of muscles indicating the tendency to cardio- and hepatocellular damage and toxicity caused by heavy metals from the polluted environment.

NUTRITIONAL CHARACTERIZATION OF COLUMBA LIVIA DOMESTICA (DOMESTIC PIGEON) AND COLUMBA GUINEA (SPECKLED PIGEON) MUSCLE TISSUE MEAL AS POTENTIAL ANIMAL PROTEIN INGREDIENT IN AQUACULTURE

The study was conducted to examine the Nutritional characterization of columba livia domestica (domestic pigeon) and columba guinea (speckled pigeon) muscle tissue meal as potential animal protein ingredient in aquaculture. The proximate composition, some mineral contents and amino acids profile were determined in Columba liviadomestica (domestic pigeon) and Columba guinea (speckled pigeon) found in Zaria, Kaduna State. The result showed significant difference in the whole weight between speckled pigeon (282.42 ±4.54) and domestic pigeon (272.66 ±8.71), gutted weight two avian species showed no significant difference (P> 0.05), domestic pigeon (201.50±4.10) had a higher gutted weight than speckled pigeon (180.68±6.34). There was significant difference in crude protein (66.70±0.70) content compared to speckled pigeon crude protein (62.18±0.32) contents. The ash content (4.51±0.14), crude fibre (0.82±0.17) and nitrogen free extract (9.82.±0.18) of speckled pigeon was lower than that of domestic pigeon with ash content (4.78±0.22), crude fibre (1.11±0.06) and nitrogen free extract (10.47±0.32). The study further disclosed significant difference in Mg, Na and K composition between the two columbid species; however; amino acid of both species did not differ significantly (P>0.05). In conclusion, speckled and domestic pigeon muscle tissues were rich in crude protein, mineral and amino acids and, therefore, recommended for use as a valuable inclusive component as animal protein sources in aquaculture feed industries.

The Role of Helminths Infecting Columba livia domestica, Pigeon in Bioremediation of Heavy Metals Accumulation (Mn, Zn, Fe)

domesticapigeons were collected from Ismailia city, Egypt, during the year 2017.They were found to be infected by intestinal helminths, two cestodes, Raillietinaechinobothridaand Cotugnia polyacantha and a nematode, Ascaridia columbae. Theheavy metals levels (Mn, Zn, and Fe) in pigeon's muscles and intestine, inaddition to helminths, were measured. R. echinobothrida revealed thehighest in heavy metals accumulation compared to C. polyacantha and A.columbae. Bioaccumulation factor was most obvious and dominant in musclesthan intestine of infected pigeons in respect to R. echinobothrida\ C.livia model ranked in concentration from highest to lowest as follows:(Mn>Zn>Fe), followed by A. columbae\ C. livia model. R.echinobothrida /C. livia , C. polyacantha/C. livia,and A.

Prevalence of Toxoplasma gondii, Neospora caninum, and Sarcocystis Species DNA in the Heart and Breast Muscles of Rock Pigeons (Columbia livia).

Little is known about the prevalence of protozoan parasites in the muscles of rock pigeons (Columbia livia). The muscles from 54 (heart from 45 and breast from 54) rock pigeons were examined for DNA of Toxoplasma gondii, Neospora caninum, and Sarcocystis species using PCR. Twenty-four were female and 30 were males. The birds were part of flocks of pigeons housed at the tombs of saints in Lahore, Pakistan. Birds that died or were euthanized due to poor health were submitted for necropsy at the Department of Parasitology, University of Veterinary and Animal Sciences, Lahore, Pakistan, where DNA isolations and PCR were conducted. Nineteen (35.1%) of the birds were positive for T. gondii DNA. Seven males and 12 females were positive. Breast tissue was always infected in T. gondii positive birds, while the heart was infected in 13 (28.8%) of breast positive birds. Five (9.2%) of the pigeons, 2 males and 3 females, were positive for N. caninum. The distribution of N. caninum DNA was more variable in the muscles of pigeons than T. gondii and was found only in the heart of 1 (female), heart and breast muscle of 2 (male), and only the breast muscle of 2 birds (female). One of the 54 rock pigeons (female) was positive for both T. gondii (heart and breast) and N. caninum (heart only). Two of the positive Neospora caninum amplicons were sequenced and had 97% nucleotide identity with N. caninum isolates. Sarcocystis DNA was not found in any bird. The prevalence of T. gondii in rock pigeons and their predation by cats suggest that they may play an unrecognized role in maintaining environmental contamination with T. gondii oocysts by cats. Our study indicates that rock pigeons are intermediate hosts of N. caninum and this information will aid in understanding the epidemiology of N. caninum.

Comparative properties of pyruvate kinase and lactate dehydrogenase from muscles of pigeons with motor activity and hypodynamia

Comparative properties of pyruvate kinase and lactate dehydrogenase from muscles of pigeons with motor activity and hypodynamia

Expression of cytosolic 5′ nucleotidase does not correlate with expression of oxidative metabolism marker: myoglobine in human skeletal muscles

Our previous studies had shown that cytosolic 5'nucleotidase-I (cN-I) is expressed in several tissues in pigeons, including brain and several different skeletal muscles. We observed that cN-I mRNA levels varied among different pigeon muscles. Initial quantification of the differences revealed that about 5-10 times more of cN-I transcript was present in red, oxidative muscles (breast muscle and gastrocnemius) than in white ones, composed of glycolytic fibers (biceps brachii). We had found this observation very intriguing and decided to compare human skeletal muscles distribution of cN-I with the type of oxygen metabolism. Our screen involved 60 samples of several human muscles and we assayed the correlation between the amount of transcripts of cN-I and myoglobine, which we took as a measure of oxidative-slow twitch fibers. Our question was whether in humans, cN-I presence in skeletal muscles was related to their fiber composition. If that was the case, then cN-I expression could serve as a tool to assess the percentage of oxidative fibers in any given human muscle sample, where myoglobine expression could not be readily measured. After quantification of expression of both genes, we concluded that there was no correlation between expression of cN-I and fiber type. Therefore, contrary to the pigeon muscles, cN-I did not reflect the ratio of oxidative fibers to the total mass of the muscle sample in humans. That difference indicated that there were certain mechanisms that differentially regulated the expression of cN-I in muscle tissues of mammals and lower vertebrates.

Blood Supply to the Pigeon Wing and Flying Muscles

In this study the vascularization of the wing and the two main breast muscles of pigeons was investigated using classical anatomical techniques. Three groups of 9‐month‐old pigeons cadavers were dissected. Each group contained six animals. The cadavers of the group no. 1 were first fixed using 4% formaldehyde solution and the arteries filled with coloured latex. After coagulation we dissected the pectoral (pectoral and supracoracoid) muscles and the supplying branches of the pectoral trunk. We followed also the subclavian, the axillary, the brachial, the radial and ulnar arteries as they vascularized the wing. The cadavers of group no. 2 were used as fresh cadavers and perfused via the brachial artery in retrograde direction with methyl–methacrylate. After the polymerization, the bodies were placed in concentrated hydrochloric acid so the microvascularization of the great breast muscles and the arteries of the wings could be investigated. The arteries of the group no. 3 were filled with BaSO4 solution after fixed with formalin and radiographed. Using this method we could represent the relation of the arteries to the bones. The breast muscles that move the wing are mainly vascularized by the pectoral trunk, which is the strongest branch of the subclavian artery and divides into the cranial, middle and the caudal pectoral arteries. Also the sternoclavicular artery is giving strong rami to the supracoracoid muscle by the lateral border of the coracoid. The subcutaneous thoracoabdominal vessels that supply the brood patches are branches of the pectoral trunk too. The brachial artery lies between the biceps and triceps brachii muscles on the medial side of the humerus and ramifies at the level proximal of the elbow joint to the stronger ulnar and weaker radial arteries. The radial lies cranially, covered by the pronator muscles and gives two branches, the deep and superficial radial arteries. The ulnar artery also gives off two: the superficial and deep ulnar arteries, which supply the flexor muscles and vascularize the distal part of the wing.

Autoradiographic localization of 2[125I]iodomelatonin binding sites in the gastrointestinal tract of mammals including humans and birds.

In-vitro autoradiography was utilized to compare the distribution of 2[125I]iodomelatonin binding sites or putative melatonin receptors in the gastrointestinal tracts of humans, guinea pigs, mice, rats, hamsters, rabbits, ducks, chickens, pigeons, and quail. In humans, binding was detected in the mucosa of the colon, caecum, appendix, and on their blood vessels but not in the ileum. In the other mammals, significant binding was only demonstrated in the mucosa of the rabbit rectum, mouse colon, mouse rectum, and guinea pig ileum. The distribution of 2[125I]iodomelatonin binding in the avian gut varied with species. In the esophagus, binding was present in the lamina propria and blood vessels of all four birds. However, only the lamina propria of the chicken and quail proventriculus and ventriculus showed positive binding. For the duodenum and ileum, binding was very strong in the duck lamina propria, weak in the chicken lamina propria, and absent in the quail. In contrast, the pigeon muscle layer was weakly positive. The most striking species difference was found in the caecum where the duck lamina propria showed very strong binding, while the chicken lamina propria was only weakly positive. Conversely, the caecal muscle layer was strongly positive in chicken and quail but negative in duck and pigeon. In the rectum, a similar but less intense pattern of distribution was observed. The tremendous diversity in the distribution of 2[125I]iodomelatonin binding sites in the gastrointestinal tract is in accord with the hypothesis that melatonin may serve different functions in the gut of different species.

Skeletal muscle capillarization and fiber types in urban and homing pigeons ( Columba livia)

1. 1. Fiber types, capillary supply and other morphometrical parameters were analysed in pectoral, gastrocnemius and pronator muscles of homing and urban pigeons. 2. 2. The two kinds of birds were analysed before and after a restrainment period of at least 5 months. 3. 3. Only slight differences in fiber type frequencies were noted between urban and horning pigeons in control conditions. 4. 4. The effect of restrainment on the different parameters studied was unclear in gastrocnemius and pronator muscles and negligible in M. pectoralis. 5. 5. Mean diffusion distances for oxygen from capillaries were smaller in oxidative fibers; also, vascularization indexes were higher for these fiber types. 6. 6. The contribution of each fiber type to total sectional area of muscle remains stable in spite of fiber type frequencies heterogeneity.

Afferent signals from the extraocular muscles of the pigeon modify the electromyogram of these muscles during the vestibulo-ocular reflex

There is no general agreement on whether afferent signals from the extraocular muscles play any part in oculomotor control. However, we have previously shown that they modify the responses of cells in the oculomotor control system during the vestibulo-ocular reflex (VOR). If, as we suspect, these signals have an important role in the control of the VOR from moment-to-moment, we should be able to demonstrate similar, functionally significant, modifications at the output of the reflex. We have recorded the electromyographic activity of several extraocular muscles of the right eye during the VOR and while imposing movements on the left eye. We describe how the activity of the muscles, reflected in the electromyogram, is modified in specific ways depending on the parameters of the imposed eye movements. The effects of the extraocular afferent signals on the eye-muscle responses to vestibular drive during the slow phase of the VOR appear to be corrective. Thus the present results provide strong evidence that afferent signals from the extraocular muscles are concerned in the control of the reflex from moment-to-moment, and suggest that the wider question of their role in oculomotor control merits further consideration.

Morphometric analysis of capillary geometry in pigeon pectoralis muscle

The objective of the study was to examine the relationship(s) between the size and the geometry of the capillary network in the flight muscle of pigeon (Columbia livia). To this end, we used morphometry to analyze the degree of anisotropy (i.e., orientation) of capillaries with respect to the axis of the muscle fibers in perfusion-fixed samples of pigeon pectoralis muscles with large difference in capillary density. Capillary number per fiber cross-sectional area (range, 1,491-5,680 mm-2) depended on fiber size (aerobic fibers, 304-782 microns 2; glycolytic, 1,785-2,444 microns 2), as well as sarcomere length (1.69-2.20 microns), and the relative sectional area of aerobic and glycolytic fibers (aerobic, 42-84% of total fiber area). The degree of tortuosity of capillaries, i.e., their bending or sinuosity relative to the muscle fiber axis, was primarily a function of sarcomere length. In spite of large differences in capillary density, capillary orientation at a given sarcomere length was remarkably similar among samples. In addition to capillaries running parallel to the muscle fiber axis, a unique arrangement of branches running perpendicular to the muscle fiber axis was found in all samples. This arrangement yielded a large circumferential distribution of capillary surface around the muscle fibers. Compared to mammalian limb muscles examined over a 10-fold range of capillary density (range, 450-4,670 mm-2), the degree of anisotropy of capillaries was greater in all samples of pigeon M. pectoralis. In the pigeon, there was no increase in the amount of capillary surface area available for exchange per microvessel as a result of a greater degree of capillary tortuosity in samples with larger capillary density (capillary number per fiber cross-sectional area greater than 4,000 mm-2), as compared to samples with a capillary density less than 4,000 mm-2.

Perfluoro- N-decanoic acid effects on enzymes of fatty acid metabolism

In vitro perfluorodecanoate (PFDA) effects on Pseudomonas acyl-CoA synthetase, Candida acyl-CoA oxidase and pigeon muscle carnitine acetyltransferase were examined. Synthetase made little PFDA-CoA from PFDA. It used palmitate, oleate, laurate and decanoate more extensively. PFDA inhibited acyl-CoA formation from these acids. Palmitoyl-CoA formation was affected most. That of decanoyl-CoA was affected least. Inhibitions appeared to be competitive. Acyl-CoA oxidase test substrates were palmitoyl-CoA, lauroyl-CoA and decanoyl-CoA. Oxidase preferred C-10 and C-12 acyl-CoAs. PFDA inhibited oxidation of C-10 and C-12 acyl-CoAs more than that of palmitoyl-CoA. Inhibitions with C-16 and C-10 acyl-CoAs were competitive, K 1s 593 ± 150 and 76 ± 6.0 μM. Acetyl-CoA was the best acetyltransferase substrate. C-2 to C-8 transfer from acyl-CoAs was inhibited similarly by PFDA. Inhibitions of C-2 and C-8 transfer were competitive and non-competitive, respectively, K 1s 111 ± 15 and 76 ± 28 μM.

Biochemical adaptations to diving in the common murre, Uria aalge, and the Atlantic puffin, Fratercula arctica

AbstractTo evaluate whether specialized biochemical adaptations facilitate the extensive breath‐hold capacities of diving alcids, we compared several such parameters in three locomotor muscles of the common murre, Uria aalge, and the Atlantic puffin, Fratercula arctica, with those in the corresponding muscles of two terrestrial species, the pigeon, Columbia livia, and the pheasant, Phasianus colchicus. The pheasant and pigeon were chosen since they provide recognizably different patterns of biochemical support for flight. The pectoral, supracoracoideus and sartorius muscles were examined since they are the major locomotor muscles. The biochemical modifications which distinguish alcid muscles from pigeon muscles are subtle but include greater hexokinase activities in pigeon muscles, greater myoglobin levels in alcid muscles, and differences in the intraspecific ranking of the muscles' capacities for glycolysis from glycogen. By contrast, the capacities for glycolysis from glycogen, the buffering capacities, and the regulatory properties of pyruvate kinase of these muscles are similar in alcids and pigeons. We conclude that diving does not require major modifications of the overall metabolic design of muscle used by a bird which is capable of sustained aerobic flight. On the other hand, the biochemical differences between pheasants and alcids are more pronounced. Pheasant pectoral has a higher capacity for glycolysis from glycogen than any of the other muscles. Flight muscles in pheasants have higher buffering capacities than those in alcids. Clearly the glycolytic specialization of pheasant flight muscles is not shared by alcid flight muscles. Thus, we suggest that alcids do not rely upon glycolysis to any considerable extent during flight or diving.

Histochemical differences in flight and leg muscles of the pigeon.

Muscle fibers of flight (pectoralis major) and leg muscles (gastrocnemius) of the adult pigeon were classified based on succinate dehydrogenase (SDH) activity and myosin adenosine triphosphatase (ATPase) activity following preincubation at various pH's. The fiber structure in semithin as well as ultrathin sections was also evaluated. The pectoral muscle was composed almost entirely of the type IIB red fiber, with type IIB white fibers representing only 3.4% of the total fibers; and the average diameter of the type IIB red fibers was 26.8μm±6.3, whereas that of the type JIB white was 50.9μm±7.9. The pectoral muscle also contained a larger amount of fat droplets and mitochondria in the type IIB red fiber, while relatively smaller amounts of fat droplets and mitochondoria were found in the IIB white fiber. These findings suggest that the major part of pigeon pectoral muscle should be categorized as a fast-twitch (alkali-stable ATPase, Type JIB) and fatigue resistant (high oxidative staining). The leg muscle of pigeon was divided into three types, the type I fiber, the type IIA and IIB fiber. Fiber diameter of the three fiber types was not much different, and the fiber population was 23.0% type I, 33.3% type IIA and 43.6% type IIB. Regarding histochemical properties, the flight and leg muscles were very different in their muscle fibers, thus reflecting the different functions of the two muscles.

Energy Metabolism in the Locomotor Muscles of the Common Murre (Uria aalge) and the Atlantic Puffin (Fratercula arctica)

Abstract To compare the metabolic systems that support the combination of flying and diving with those used to support burst flying and sustained flying, myoglobin concentrations and maximum enzyme activities were determined for selected enzymes of glycolysis, the Krebs cycle, and amino acid metabolism in the pectoral, supracoracoideus, and sartorius muscles of the Common Murre (Uria aalge), Atlantic Puffin (Fratercula arctica), Rock Dove (Columba livia; hereafter "pigeon"), and Ring-necked Pheasant (Phasianus colchicus). Glycolytic enzyme levels in the flight muscles were lower in the murre and the puffin than in the pheasant, while both glycolytic and Krebs-cycle enzyme levels resembled those in the pigeon. We believe puffins and murres do not rely extensively on anaerobic glycolysis during diving. In concordance with a role in oxygen storage for diving, the levels of myoglobin in the flight muscles of murres and puffins were higher than those in pigeons or pheasants. They were lower than published values for penguins, however. In contrast to the trends for pigeon and pheasant muscles, the alcid sartorius muscles had a considerably lower aerobic orientation than the flight muscles.