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Showing papers on "Incubation published in 2013"


Journal ArticleDOI
TL;DR: Observations suggest that incubation temperature (and incubation behaviours of parents) is an important but underappreciated parental effect in birds and may represent a selective force instrumental in shaping avian reproductive ecology and life‐history traits.
Abstract: Incubation is a vital component of reproduction and parental care in birds. Maintaining temperatures within a narrow range is necessary for embryonic development and hatching of young, and exposure to both high and low temperatures can be lethal to embryos. Although it is widely recognized that temperature is important for hatching success, little is known about how variation in incubation temperature influences the post-hatching phenotypes of avian offspring. However, among reptiles it is well known that incubation temperature affects many phenotypic traits of offspring with implications for their future survival and reproduction. Although most birds, unlike reptiles, physically incubate their eggs, and thus behaviourally control nest temperatures, variation in temperature that influences embryonic development still occurs among nests within a population. Recent research in birds has primarily been limited to populations of megapodes and waterfowl; in each group, incubation temperature has substantial effects on hatchling phenotypic traits important for future development, survival, and reproduction. Such observations suggest that incubation temperature (and incubation behaviours of parents) is an important but underappreciated parental effect in birds and may represent a selective force instrumental in shaping avian reproductive ecology and life-history traits. However, much more research is needed to understand how pervasive phenotypic effects of incubation temperature are among birds, the sources of variation in incubation temperature, and how effects on phenotype arise. Such insights will not only provide foundational information regarding avian evolution and ecology, but also contribute to avian conservation.

226 citations


Journal ArticleDOI
TL;DR: The results provide the first evidence for release of bound residues during alteration of the redox environment and indicate that sequential anoxic-oxic incubation approaches-considered effective in remediation of environments containing halogenated xenobiotics-do not completely remove Xenobiotics from environmental matrices.
Abstract: Tetrabromobisphenol A (TBBPA) is one of the most commonly used flame retardants and has become an environmental contaminant worldwide We studied the fate of (14)C-labeled TBBPA in soil under static anoxic (195 days) and sequential anoxic (125 days)-oxic (70 days) conditions During anoxic incubation, TBBPA dissipated with a half-life of 36 days, yielding four debromination metabolites: bisphenol A (BPA) and mono-, di-, and tribrominated BPA At the end of anoxic incubation, all four brominated BPAs completely disappeared, leaving BPA (54% of initial TBBPA) as the sole detectable organic metabolite TBBPA dissipation was accompanied by trace mineralization (<13%) and substantial bound-residue formation (35%), probably owing to chemical binding to soil organic matter Subsequent oxic incubation was effective in degrading accumulated BPA (half-life 11 days) through mineralization (6%) and bound-residue formation (62%) However, 42% of the anoxically formed bound residues was released as TBBPA and lower brominated BPAs, which were then persistent during oxic incubation Our results provide the first evidence for release of bound residues during alteration of the redox environment and indicate that sequential anoxic-oxic incubation approaches-considered effective in remediation of environments containing halogenated xenobiotics-do not completely remove xenobiotics from environmental matrices

123 citations


Journal ArticleDOI
TL;DR: In this paper, the authors investigated the effect of the type of creative task (verbal or spatial) and the kind of incubation activity on creative performance and found that spatial incubation benefited verbal fluency and verbal-rated creativity but not vice versa.
Abstract: The experiment reported here investigated interactions between the type of creative task (verbal or spatial) and the type of incubation activity (verbal or spatial) on creative performance. The experiment used a verbal creative divergent thinking task (Alternative Uses) and a spatial creative task (Mental Synthesis). After 5 minutes of conscious work on Alternative Uses or Mental Synthesis, experimental groups had 5-minute incubation periods which involved either spatial (Mental Rotation) or verbal tasks (Anagrams). Following incubation, the experimental participants resumed their main task for a further 5 minutes. Control groups undertook Alternative Uses or Mental Synthesis for 10 minutes without any incubation periods. Significant incubation effects were found overall and there were interactions in that spatial incubation benefited verbal fluency and verbal-rated creativity, and verbal incubation benefited spatial-task fluency and spatial-rated creativity but not vice versa. The results supported a rol...

66 citations


Journal ArticleDOI
TL;DR: Weather conditions appeared to be particularly important in determining the extent to which corticosterone levels affected the behaviour of penguins, as treated penguins were more sensitive to severe weather conditions.

62 citations


Journal ArticleDOI
19 Jun 2013-PLOS ONE
TL;DR: It is found that the rate of heat loss from eggs increased with embryo age, and the need to view full incubation as more than a static rhythm is highlighted; rather, it is a temporally dynamic and finely adjustable parental behavior.
Abstract: Incubation conditions for eggs influence offspring quality and reproductive success. One way in which parents regulate brooding conditions is by balancing the thermal requirements of embryos with time spent away from the nest for self-maintenance. Age related changes in embryo thermal tolerance would thus be expected to shape parental incubation behavior. We use data from unmanipulated Black-capped Chickadee (Poecile atricapillus) nests to examine the temporal dynamics of incubation, testing the prediction that increased heat flux from eggs as embryos age influences female incubation behavior and/or physiology to minimize temperature fluctuations. We found that the rate of heat loss from eggs increased with embryo age. Females responded to increased egg cooling rates by altering incubation rhythms (more frequent, shorter on- and off- bouts), but not brood patch temperature. Consequently, as embryos aged, females were able to increase mean egg temperature and decrease variation in temperature. Our findings highlight the need to view full incubation as more than a static rhythm; rather, it is a temporally dynamic and finely adjustable parental behavior. Furthermore, from a methodological perspective, intra- and inter-specific comparisons of incubation rhythms and average egg temperatures should control for the stage of incubation.

62 citations


Journal ArticleDOI
TL;DR: It is demonstrated that providing 12 h of light per day during incubation can reduce the stress susceptibility of broilers posthatch.

56 citations


Journal ArticleDOI
TL;DR: The SPIDES treatment, which consisted of four 4-h preincubations at 4- to 5-d intervals during storage, reduced the incubation time and restored hatchability to 84% by lowering both early and late embryo mortality by alleviating the negative effects of storage-induced cell death on embryo development.

54 citations


Journal ArticleDOI
TL;DR: Inverse analyses with data from a long-term incubation experiment with two types of soil to deconvolute soil carbon efflux into different source pools indicated that soil C release trajectories over the 385 days of the incubation study were best modeled with a two-pool C model.
Abstract: Soil organic matter (SOM) is heterogeneous in structure and has been considered to consist of various pools with different intrinsic turnover rates. Although those pools have been conceptually expressed in models and analyzed according to soil physical and chemical properties, separation of SOM into component pools is still challenging. In this study, we conducted inverse analyses with data from a long-term (385 days) incubation experiment with two types of soil (from plant interspace and from underneath plants) to deconvolute soil carbon (C) efflux into different source pools. We analyzed the two datasets with one-, two- and three-pool models and used probability density functions as a criterion to judge the best model to fit the datasets. Our results indicated that soil C release trajectories over the 385 days of the incubation study were best modeled with a two-pool C model. For both soil types, released C within the first 10 days of the incubation study originated from the labile pool. Decomposition of C in the recalcitrant pool was modeled to contribute to the total CO2 efflux by 9–11 % at the beginning of the incubation. At the end of the experiment, 75–85 % of the initial soil organic carbon (SOC) was modeled to be released over the incubation period. Our modeling analysis also indicated that the labile C-pool in the soil underneath plants was larger than that in soil from interspace. This deconvolution analysis was based on information contained in incubation data to separate carbon pools and can facilitate integration of results from incubation experiments into ecosystem models with improved parameterization.

53 citations


Journal ArticleDOI
TL;DR: In this study, the 3,4-dihydroxybenzoic acid from Terminalia nigrovenulosa bark was purified and its in vitro nematicidal activity was investigated against Meloidogyne incognita.

52 citations


Journal ArticleDOI
TL;DR: It was found that broods of both domesticated and wild birds taken into captivity hatched more asynchronously than wild free-living broods, suggesting that something about the captive environment is driving the early onset of incubation and contributing to an elevated level of hatching asynchrony in captive birds.

51 citations


Journal ArticleDOI
TL;DR: The poor bioavailability of Copper has resulted in high excretion rate of Cu in the faeces of animals, and its effect on soil microorganisms, plants and aquatic species is today one of the crucial environmental concerns.

Journal ArticleDOI
TL;DR: An overview of the most relevant pre-incubation factors that affect chick quality: egg size, egg weight, quality of eggs, sex of embryos, age of breeders, and conditions and duration of egg storage is presented.
Abstract: The zootechnical performances of broilers at the end of the rearing period depend in part on the quality of day-old chicks at placement. The quality of day-old chicks is highly affected by the incu...

Journal ArticleDOI
TL;DR: The study suggested that the WST-1 is a proper candidate reagent for continuous monitation of cell viability in rat airway smooth muscle cells after adding of the testing protein MRP-14.
Abstract: The WST-1 assay is an efficient test for cell viability measurement and the standard incubation time is 2h In order to test if one-time addition of WST-1 reagent can reflect the relative cell viability trend of the testing agents at different time points, the effects of 2h standard incubation time and long term incubation time (2h+24h, 2h+48h) of WST-1 were compared in the rat airway smooth muscle cells (ASM cells) after adding of the testing protein MRP-14 Our study demonstrated that the effect of different dosages of the protein after 2h WST-1 incubation on ASM cells showed a tendency of inhibition and achieved the maximal inhibition effect at 72h The relative cell viability trend of the 2h+24h group was the same to that of the 2h WST-1 incubation, which means that 24h prolonged incubation time of WST-1 reagent could still reflect the relative cell viability trend In conclusion, the study suggested that the WST-1 is a proper candidate reagent for continuous monitation of cell viability

Journal ArticleDOI
TL;DR: An esterase gene, est10, was identified from the genomic library of a deep-sea psychrotrophic bacterium Psychrobacterpacificensis, and was fairly stable under room temperatures, retaining more than 80 % of its original activity after incubation at 40 °C for 2 h.
Abstract: An esterase gene, est10, was identified from the genomic library of a deep-sea psychrotrophic bacterium Psychrobacter pacificensis. The esterase exhibited the optimal activity around 25 °C and pH 7.5, and maintained as high as 55.0 % of its maximum activity at 0 °C, indicating its cold adaptation. Est10 was fairly stable under room temperatures, retaining more than 80 % of its original activity after incubation at 40 °C for 2 h. The highest activity was observed against the short-chain substrate p-nitrophenyl butyrate (C4) among the tested p-nitrophenyl esters (C2–C16). It was slightly activated at a low concentration (1 mM) of Zn2+, Mg2+, Ba2+, Ca2+, Cu2+, Fe3+, urea and EDTA, but was inhibited by DTT and totally inactivated by PMSF. Interestingly, increased salinity considerably stimulated Est10 activity (up to 143.2 % of original activity at 2 M NaCl) and stability (up to 126.4 % after incubation with 5 M NaCl for 6.5 h), proving its salt tolerance. 0.05 and 0.1 % Tween 20, Tween 80, Triton X-100 and CHAPS increased the activity and stability of Est10 while SDS, CTAB had the opposite effect. Est10 was quite active after incubation with several 30 % organic solvents (methanol, DMSO, ethanediol) but exhibited little activity with 30 % isopropanol, ethanol, n-butanol and acetonitrile.

Journal ArticleDOI
TL;DR: The results suggest that V. fluvialis L-21 is able to stimulate in vitro some immune-related genes associated with the early inflammatory response in sea bass.

16 Oct 2013
TL;DR: Overall, manipulations in environmental temperature during incubation produced more drastic changes in embryo development than humidity-related manipulations, especially where mortality and malformation rates were concerned.
Abstract: Temperature and relative humidity (RH) are very important factors affecting embryo development, hatchability, and posthatch performance. This study aimed at characterizing embryonic metabolic and behavioural response to a harsh incubation environment generated by manipulations (elevations and drops) in these two key factors. This study was aimed at establishing patterns of metabolic and behavioural response, as well as mortality and the development of malformations, all of which can potentially be used in monitoring incubating operations and diagnosing problems with faulty equipment. Of all the parameters monitored throughout embryonic development the ones shown to be most affected were: albumen-weight to egg-weight ratio (AR); yolk-weight to egg-weight ratio (YR); embryo-weight to egg-weight ratio (ER); heart rate (HR); voluntary movements per minute (VMM); mortality rates; malformation prevalence and type. The most significant changes in the evolution of AR and YR throughout incubation involved delay and reduction in the amplitude of the expected drop in albumen and yolk levels, reflecting lower nutrient consumption by the embryo. ER tended to grow more slowly and remain lower than the established normal, especially in embryos challenged with temperature treatments. HR and VMM were considered to be strong indicators of embryonic stress, as all treatments applied resulted in elevated heart rate and decreased embryo movement. Mortality rates for both temperature-related treatments were higher during the first four days of incubation. Changes in relative humidity have produced less radical effects on mortality. Malformation rates were higher for embryos subjected to high incubation temperatures and were most prominently related to the abdominal wall, head, skull and limbs. Overall, manipulations in environmental (incubator) temperature during incubation produced more drastic changes in embryo development than humidity-related manipulations, especially where mortality and malformation rates were concerned. This paper describes changes in embryonic metabolism and behaviour, as well as in mortality and malformation rates, in response to manipulations in environmental temperature and relative humidity. Together with further studies, these patterns may prove helpful in the diagnosis of equipment malfunctions relating to temperature or relative humidity.

Journal ArticleDOI
TL;DR: It is indicated that incubation temperature can significantly influence the culturability and detection of thermophilic and other fastidious Campylobacter spp.
Abstract: This large-scale study compared incubation temperatures (37°C versus 42°C) to study the detection of thermophilic Campylobacter species, including Campylobacter jejuni, C. coli, and C. lari, in various surface water samples and bird fecal droppings around Hamilton Harbor, Lake Ontario. The putative culture isolates obtained from incubation temperatures of 37 and 42°C were confirmed by Campylobacter genus- and species-specific triplex PCR assays targeting the 16S rRNA gene and the 16S-23S rRNA gene internal transcribed spacer (ITS) region. A total of 759 water, wastewater, and bird fecal dropping samples were tested. Positive amplification reactions for the genus Campylobacter were found for 454 (60%) samples incubated at 37°C, compared to 258 (34%) samples incubated at 42°C. C. jejuni (16%) and C. lari (12%) were detected significantly more frequently at the 42°C incubation temperature than at 37°C (8% and 5%, respectively). In contrast, significantly higher rates of C. coli (14%) and other Campylobacter spp. (36%) were detected at the 37°C incubation temperature than at 42°C (8% and 7%, respectively). These results were consistent across surface water, wastewater, and bird fecal dropping samples. At times, Campylobacter spp. were recovered and detected at 37°C (3% for C. jejuni, 10% for C. coli, and 3% for C. lari) when the same samples incubated at 42°C were negative. A significantly higher rate of other Campylobacter spp. was detected only at 37°C (32%) than only at 42°C (3%). These results indicate that incubation temperature can significantly influence the culturability and detection of thermophilic and other fastidious Campylobacter spp. and that a comprehensive characterization of the Campylobacter spp. in surface water, wastewaters, or bird fecal droppings will require incubation at both 37 and 42°C.

Journal ArticleDOI
TL;DR: Based on the results, MMH medium appears to be a suitable medium for susceptibility testing of antifungal drugs with P. brasiliensis, except for sulfamethoxazole and the combination of sulfametazole-trimethoprim, for which the MVM medium yielded better results.
Abstract: MIC assays with Paracoccidioides brasiliensis, the etiological agent of paracoccidioidomycosis, had been conducted with variable protocols, employing both macrodilution and microdilution tests and including differences in inoculum preparation, media used, incubation periods, and temperatures. Twenty-one clinical and environmental isolates of Paracoccidioides were tested using amphotericin B, itraconazole, ketoconazole, fluconazole, sulfamethoxazole, sulfamethoxazole-trimethoprim, and terbinafine, according to the National Committee for Clinical Laboratory Standards (National Committee for Clinical Laboratory Standards, document M27-A2, 2002), with modifications such as three medium formulations (RPMI 1640 medium, McVeigh and Morton [MVM] medium, and modified Mueller-Hinton [MMH] medium), two incubation temperatures (room temperature [25 to 28 °C] and 37 °C), and three incubation periods (7, 10, and 15 days). The antifungal activities were also classified as fungicidal or fungistatic. The best results were obtained after 15 days of incubation, which was chosen as the standard incubation time. The MICs for most individual isolates grown for the same length of time at the same temperature varied with the different media used (P < 0.05). Of the isolates, 81% showed transition from the yeast to the mycelial form in RPMI 1640 medium at 37 °C, independent of the presence of antifungals. MMH medium appears to be a suitable medium for susceptibility testing of antifungal drugs with P. brasiliensis, except for sulfamethoxazole and the combination of sulfamethoxazole-trimethoprim, for which the MVM medium yielded better results. The incubation temperature influenced the MICs, with, in general, higher MICs at 25 °C (mycelial form) than at 37 °C (P < 0.05). Based on our results, we tentatively propose a microdilution assay protocol for susceptibility testing of antifungal drugs against Paracoccidioides.

Journal ArticleDOI
01 Apr 2013-PLOS ONE
TL;DR: Results indicate that the glucose oxidation pattern is relatively slow, but the intensity increased consistently with an increase in developmental stage of the embryo, probably by increased gluconeogenesis from glucogenic amino acids to allow anaerobic glycolysis.
Abstract: Environmental conditions during the perinatal period influence metabolic and developmental processes in mammals and avian species, which could impact pre- and postnatal survival and development. The current study investigated the effect of eggshell temperature (EST) on glucose metabolism in broiler chicken embryos. Broiler eggs were incubated at a high (38.9°C) or normal (37.8°C) EST from day 10.5 of incubation onward and were injected with a bolus of [U-13C]glucose in the chorio-allantoic fluid at day 17.5 of incubation. After [U-13C]glucose administration, 13C enrichment was determined in intermediate pools and end-products of glucose metabolism. Oxidation of labeled glucose occurred for approximately 3 days after injection. Glucose oxidation was higher in the high than in the normal EST treatment from day 17.6 until 17.8 of incubation. The overall recovery of 13CO2 tended to be 4.7% higher in the high than in the normal EST treatment. An increase in EST (38.9°C vs 37.8°C) increased 13C enrichment in plasma lactate at day 17.8 of incubation and 13C in hepatic glycogen at day 18.8 of incubation. Furthermore, high compared to normal EST resulted in a lower yolk-free body mass at day 20.9 (−2.74 g) and 21.7 (−3.81 g) of incubation, a lower hepatic glycogen concentration at day 18.2 (−4.37 mg/g) and 18.8 (−4.59 mg/g) of incubation, and a higher plasma uric acid concentration (+2.8 mg/mL/+43%) at day 21.6 of incubation. These results indicate that the glucose oxidation pattern is relatively slow, but the intensity increased consistently with an increase in developmental stage of the embryo. High environmental temperatures in the perinatal period of chicken embryos increased glucose oxidation and decreased hepatic glycogen prior to the hatching process. This may limit glucose availability for successful hatching and could impact body development, probably by increased gluconeogenesis from glucogenic amino acids to allow anaerobic glycolysis.

Journal ArticleDOI
TL;DR: It was concluded that thermal treatments preincubation or during the sex determination period of incubation had a positive effect on hatchability, growth performance, and secondary sexual characteristics of broiler males and females, probably caused by the increase of plasma testosterone concentration in both sexes.

Journal ArticleDOI
TL;DR: It is suggested that the decreased prolactin levels in treated birds offset their timeline of breeding, so that birds displayed behavior typical of early incubation.

Journal ArticleDOI
TL;DR: The findings suggest that the prehatch environment is more important than posthatch resource conditions in determining some physiological functions and underscores the important role that incubation temperature plays in determining offspring phenotype in birds.
Abstract: Recent research in birds suggests that investing in incubation is one mechanism by which parents can enhance the phenotype of their offspring. Posthatch environmental conditions can also shape an individual's phenotype, and it is thus possible for pre- and posthatch conditions to have interactive effects on an individual's phenotype. In this study, we examined the individual and interactive effects of prehatch incubation temperature and posthatch food availability on growth, food consumption, and thermoregulatory ability in wood duck (Aix sponsa) ducklings. Eggs were incubated at one of three temperatures (35.0°, 35.9°, or 37.0°C), and then ducklings were reared on an either ad lib. or time-restricted diet for 12 d after hatching. We found that food availability influenced duckling growth, with the slowest growth occurring in ducklings fed the restricted diet. Incubation temperature also interacted with food conditions to influence duckling growth: ducklings fed ad lib. from the lowest incubation temperature grew slower than ducklings fed ad lib. from the higher incubation temperatures. Most importantly, we found that the improvement in a duckling's ability to maintain body temperature in the face of a thermal challenge was influenced by embryonic incubation temperature but not feeding conditions. Ducklings from the highest incubation temperature experienced the greatest improvement in thermoregulatory performance with age. Our findings suggest that the prehatch environment is more important than posthatch resource conditions in determining some physiological functions and underscores the important role that incubation temperature plays in determining offspring phenotype in birds.

Journal ArticleDOI
TL;DR: The results of the present study highlight the long-term influence of hatching date that integrates female reproductive timing and incubation conditions, and highlight the positive influence of defensive behaviour at birth in cool-incubated individuals.
Abstract: Understanding variations in individual trajectories is a crucial evolutionary issue. Terrestrial ectotherms from temperate regions typically face thermal constraints and limited activity periods. Developmental conditions (i.e. embryonic life) and reproductive timing (laying date) should induce phenotypic variations and influence subsequent ontogenetic trajectories (growth and survival). We studied these combined influences in an oviparous squamate, the wall lizard (Podarcis muralis), comprising a multiple clutch species with natural variations in laying date for the first clutch. We experimentally manipulated maternal basking opportunities during gravidity (3, 6 or 9 h per day) and incubation temperature (23 or 29 °C). Early laying date positively influenced winter survival in both incubation treatments. Survival was significantly lower in cool than warm-incubated individuals (14.8% and 73.6%, respectively) because of delayed hatching date and reduced activity period before winter. Individuals from cool incubation temperature were slightly smaller but had a higher body condition and grew faster during the first month of life. Offspring behaviour was driven by complex interactions between gravidity and incubation treatments. Under cool incubation temperature, defensive behaviour was high, independently of gravidity treatment. Warm incubated individuals showed low defensive response except when maternal basking opportunities were restricted to 3 h. Defensive behaviour at birth had a positive influence on survival in cool-incubated individuals. The results of the present study highlight the long-term influence of hatching date that integrates female reproductive timing and incubation conditions. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 00, 000–000.

Journal ArticleDOI
TL;DR: These extended egg periods likely reflect slower embryonic growth and development at a given egg temperature, which would require an increase in either post-fledging survival or adult reproductive success to favor a slow-growth evolutionary strategy.
Abstract: Many species of tropical birds have prolonged incubation periods compared to other tropical species and to most species in temperate latitudes. One hypothesis for prolonged incubation is that these tropical species reduce nest attendance to minimize the risk of predation. The resulting decrease in average egg temperature would reduce embryo growth rate and lengthen the embryo development period. We sampled six species of Neotropical, lowland, inner forest antbirds (Thamnophilidae) and flycatchers (Tyrannidae) with average incubation periods between 17.9 and 23.3 days. Estimated total integrated 24-h nest attendance between clutch completion and hatching ranged between 14.2 and 19.5 days, representing 71–84 % of the incubation periods. Because total nest attendance in these species exceeded the incubation periods of most small passerine birds in temperate latitudes, and because average nest attendance per day did not differ substantially between these tropical species and temperate species, reduced nest attendance does not appear to cause their prolonged incubation periods. Instead, these extended egg periods likely reflect slower embryonic growth and development at a given egg temperature. Prolonged incubation can increase time-dependent mortality in the nest, which would require an increase in either post-fledging survival or adult reproductive success to favor a slow-growth evolutionary strategy. Mechanisms underlying the postulated trade-off between incubation period length and individual quality merit further investigation.

Journal ArticleDOI
TL;DR: It is suggested that temperature variation does not affect the phenotype of hatchlings in L. agilis, and data show that both the type and the magnitude of temperature variation can affect incubation length.
Abstract: Li, H., Zhou, Z.-S., Ding, G.-H. and Ji, X. 2013. Fluctuations in incubation temperature affect incubation duration but not morphology, locomotion and growth of hatchlings in the sand lizard Lacerta agilis (Lacertidae). — Acta Zoologica (Stockholm) 94: 11‐18. Studies looking for potential effects of temperature and temperature fluctuations on phenotypic traits of reptile hatchlings have shown species variation, but have not always allowed a distinction between effects of fluctuation per se and temperature extremes themselves. To examine whether incubation temperature fluctuation has a key role in influencing the phenotype of offspring, we incubated eggs of the sand lizard Lacerta agilis at one of the four temperature regimes (27, 27 ± 2, 27 ± 4 and 27 ± 6 � C). We found that: (1) hatchlings incubated under the four temperature regimes did not differ from each other in any of the morphological and physiological traits examined; (2) interactions that included temperature treatment did not affect any trait examined; (3) the mean incubation length was longer in the 27 ± 6 � C treatment than in the other three treatments; and (4) female hatchlings were shorter in head length and width but longer in snout-vent length as well as abdomen length than males derived from the samesized egg. Our data show that both the type and the magnitude of temperature variation can affect incubation length. We found no evidence for phenotypic divergence in responses to temperature fluctuations during incubation and therefore suggest that temperature variation does not affect the phenotype of hatchlings in L. agilis.

Journal ArticleDOI
TL;DR: Results indicate that the in ovo injected pigeon may hatch with more mature enterocytes and greater intestinal digestive and absorptive capacity than the conventional hatchling and may become more precocial at hatch and easier to hand-rear during the immediate posthatch period.
Abstract: The objective of this study was to test the hypothesis that in ovo injection of carbohydrates into pigeon (Columba livia) amnion may improve the small intestine development. At d 14.5 of incubation, 80 fertile eggs were injected with 200 μL of carbohydrate solution, and 80 control eggs were not injected. The carbohydrate solution (wt/vol) contained 2.5% maltose + 2.5% sucrose, all dissolved in 0.75% saline. Twelve eggs from each treatment were randomly sampled at d 16 of incubation and the day of hatch, embryos or young pigeons were euthanized, and the jejunum samples were collected. Jejunal villus surface area, activity of the brush border enzymes, sucrase, maltase, aminopeptidase-N, and alkaline phosphatase, and mRNA expression of the digestion-absorption related genes oligopeptide transporter 1, sodium glucose transporter 1, glucose transporter 2, aminopeptidase-N, and sucrase-isomaltase were examined. Results showed that in ovo injection of carbohydrate solution caused a villus surface area increase of 38% on d 16 of incubation and 23% on day of hatch relative to controls (P < 0.05). The in ovo injected pigeons exhibited greater (P < 0.05) activities of jejunal sucrase, maltase, and alkaline phosphatase from d 16 of incubation to day of hatch compared with the controls. At day of hatch, aminopeptidase-N activity in embryos injected in ovo was approximately 27% greater (P < 0.05) than control embryos. Enhanced expressions of the jejunal sodium glucose transporter 1, glucose transporter 2, and aminopeptidase-N mRNA were found at d 16 of incubation in embryos that received carbohydrate solution into the amniotic fluid in comparison with the control group (P < 0.05). These results indicate that the in ovo injected pigeon may hatch with more mature enterocytes and greater intestinal digestive and absorptive capacity than the conventional hatchling. Therefore, the in ovo injected pigeons may become more precocial at hatch and easier to hand-rear during the immediate posthatch period.

Journal ArticleDOI
TL;DR: Line of evidence support the hypothesis that incubation in wood ducks is energetically costly and corticosterone is important in supporting the energetic demands of incubating hens and that there is a greater physiological cost associated with incubating larger clutches.

Journal ArticleDOI
22 Jan 2013-PLOS ONE
TL;DR: The data confirm the protective role of endogenous Sod1 in prion disease and suggest that polymorphisms at these loci contribute to the natural variation observed in incubation time.
Abstract: Prion infections, causing neurodegenerative conditions such as Creutzfeldt-Jakob disease and kuru in humans, scrapie in sheep and BSE in cattle are characterised by prolonged and variable incubation periods that are faithfully reproduced in mouse models. Incubation time is partly determined by genetic factors including polymorphisms in the prion protein gene. Quantitative trait loci studies in mice and human genome-wide association studies have confirmed that multiple genes are involved. Candidate gene approaches have also been used and identified App, Il1-r1 and Sod1 as affecting incubation times. In this study we looked for an association between App, Il1-r1 and Sod1 representative SNPs and prion disease incubation time in the Northport heterogeneous stock of mice inoculated with the Chandler/RML prion strain. No association was seen with App, however, significant associations were seen with Il1-r1 (P = 0.02) and Sod1 (P<0.0001) suggesting that polymorphisms at these loci contribute to the natural variation observed in incubation time. Furthermore, following challenge with Chandler/RML, ME7 and MRC2 prion strains, Sod1 deficient mice showed highly significant reductions in incubation time of 20, 13 and 24%, respectively. No differences were detected in Sod1 expression or activity. Our data confirm the protective role of endogenous Sod1 in prion disease.

Journal ArticleDOI
TL;DR: It is suggested that muscle proteolysis is transiently increased by the removal of albumen before the start of incubation, indicating an altered protein metabolism in albumen-deprived chicks.
Abstract: Albumen was removed from broiler eggs before the start of incubation to induce prenatal protein under-nutrition in chicken embryos. With this method, the direct effect of protein deficiency was investigated, differing from mammalian models manipulating the maternal diet where indirect, hormonal effects can interfere. Based on the estimated albumen/egg weight ratio, 10 % of albumen was removed with an 18G needle, after making a hole at the sharp end of the egg with another 18G needle. Eggs were taped thereafter. The sham group underwent the same procedure, except that no albumen was removed. Control eggs did not receive any treatment. The removal of albumen decreased both embryonic and post-hatch body weight up to day 7 compared with the control group. On embryonic day 18, embryos from the albumen-deprived group had higher plasma uric acid levels compared with the sham (P= 0·016) and control (P= 0·009) groups. Moreover, a lower plasma amino acid concentration was observed at hatch compared with the sham (P= 0·038) and control (P= 0·152) groups. These findings indicate an altered protein metabolism. At hatch, a higher mRNA expression of muscle ring finger-1 (MuRF1), a gene related to proteolysis, was observed in albumen-deprived chicks compared with the control and sham chicks, together with an up-regulated expression of atrogin-1 (another atrogene) at this time point in the male protein-deficient chicks. These findings suggest that muscle proteolysis is transiently increased by the removal of albumen before the start of incubation. No evidence was found for altered protein synthesis capacity and translational efficiency in albumen-deprived chicks.

Journal ArticleDOI
TL;DR: In this paper, a laboratory incubation experiment was conducted to determine the nitrogen release pattern from vermicompost (V.C), poultry manure (P.M), neem, inorganic fertilizer (I.O), V.C+Neem and its combinations applied to an acid soil at two different rates.
Abstract: Study of nitrogen release pattern from organic manures is very essential to ensure nitrogen supply in adequate quantity and at proper time to crop plants in an acid soil. A laboratory incubation experiment was conducted to determine the nitrogen release pattern from vermicompost (V.C), poultry manure (P.M), neem, inorganic fertilizer (I.O) and its combinations applied to an acid soil at two different rates. Cumulative nitrogen mineralization was significantly higher throughout the incubation period for I.O, V.C+P.M and I.O+V.C while it was two weeks after incubation for V.C and V.C+Neem due to the inhibitory effect of neem on nitrification. The results indicated a significant increase in the rate of N mineralization in the first one week in which the highest rate of 3.36 mg N day -1 was observed for inorganic fertilizer and thereafter it slowed down. V.C followed by V.C+Neem recorded higher rate of N mineralization of 0.24 and 0.23 mg day -1 respectively, from 48 th days after incubation. V.C+Neem at 120 kg N equivalent ha -1 recorded the highest ammonia content of 42.1% to total available N while V.C+P.M recorded higher nitrate content of 82.3% at the end of the incubation period. Positive correlation between initial nitrogen and total mineralized N from the manures and fertilizers (R 2 = 0.563) was observed. Furthermore, addition of organic manures resulted in increase in soil pH where as inorganic fertilizer showed a slight decrease (5.73) than control (5.78).