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Diplonychus indicus, a tropical, skilled predatory water bug with a global distribution, has been studied for its predatory performance. In this study, a detailed account and a thorough assessment on the population dynamics, reproductive fecundity, and the various factors, viz., effect of space size, temperature, food deprivation, aquatic vegetation, competition, and prey density influencing the predatory performance of D. indicus have been portrayed. Over the course of a year, the population dynamics of D. indicus was observed in a permanent pond located in the Kanyakumari region of Tamil Nadu, Southern India. Except for temperature, D. indicus nymphs and adults, had a positive correlation with abiotic (temperature, pH, dissolved oxygen, and rainfall) and biotic (Culex larvae) parameters. With regard to reproductive fecundity, on an average, 20 female individuals of D. indicus produced 1062 eggs, with a maximum hatching percentage of 88.3 at water temperatures of 25–26 °C, and an incubation period of 9.0 ± 0.35 days. The stadial duration of nymphs was 77.68 days, with the Ist stage being the shortest (5.2 ± 0.32 days) and the Vth stage the longest (34.22 ± 4.12). The IVth stage followed by the Vth stage had the highest rates of survival from egg to adult. The predatory performance of D. indicus nymphs evaluated based on the following factors, viz., space size, temperature, starvation, vegetation, competition, and prey density, are as follows. Maximum number of prey (Culex larvae) predated (411.20 ± 8.76) was in circular experimental glass container of 1 L volume space size; at a temperature of 25 °C (11.20 ± 0.30); after 24 h of starvation (558.26 ± 2.56); in 2.0 g density of aquatic vegetation (388.16 ± 2.32); with six competitors (2484.60 ± 8.10); and at 80 prey density (28.52 ± 1.02). The current study provides a critical insight into these variables that are crucial in the predatory performance of their prey, and are successful parameters in establishing a specific predator-prey interaction. This is a useful parameter for figuring out a specific predator-prey interaction in the wild. All the above mentioned factors will affect how well D. indicus performs as a predator in the field. [ABSTRACT FROM AUTHOR]

Maternal provisioning and the developmental environment are fundamental determinants of offspring traits, particularly in oviparous species. However, the extent to which embryonic responses to these factors differ across populations to drive phenotypic variation is not well understood. Here, we examine the contributions of maternal provisioning and incubation temperature to hatchling morphological and metabolic traits across four populations of the American alligator (Alligator mississippiensis), encompassing a large portion of the species' latitudinal range. Our results show that whereas the influence of egg mass is generally consistent across populations, responses to incubation temperature show population‐level variation in several traits, including mass, head length, head width, and residual yolk mass. Additionally, the influence of incubation temperature on developmental rate is greater at northern populations, while the allocation of maternal resources toward fat body mass is greater at southern populations. Overall, our results suggest that responses to incubation temperature, relative to maternal provisioning, are a larger source of interpopulation phenotypic variation and may contribute to the local adaptation of populations. [ABSTRACT FROM AUTHOR]

Here we investigate possible carryover effects of experimentally increased incubation temperatures for postnatal growth, metabolism, and parental care within and among 6 north temperate and one tropical songbird species. Increased temperatures during embryonic development consistently caused higher postnatal resting metabolism compared to control nests, among but not within the 7 species studied. The effects of the experiment on growth were species specific and depended on the morphometric considered. Size before the fledge date was positively correlated with feeding rate, and metabolism was lower in larger broods. Our experiment did not elicit changes in parental food delivery rates or brooding effort during the postnatal stage, and higher brooding effort was associated with nestlings of smaller mass and faster metabolism independently from treatment. Consequently, parental care seemed unlikely to be the cause of the differences in growth rates between treatments. Instead, physiological mechanisms triggered by our heating treatment appear to be responsible for the observed variation in growth. These intrinsic changes unmatched by adjustments in parental effort may contribute to longer-term consequences for individual quality and survival that deserve further attention. [ABSTRACT FROM AUTHOR]

The copepod genus Oithona is among the most abundant mesozooplankton in both eutrophic and oligotrophic waters. This paper reports the individual and combined effect of temperature and pH on the development, reproduction success, and feeding preference of the tropical species Oithona rigida. Experiments were conducted at different temperature (28, 30, 31, and 32°C) and pH (7.7, 7.9, and 8.1) conditions. Effects on vital rates were observed for different developmental stages and adult males. Sex ratio varied from near 1:1 at 28°C to almost entirely female at 32°C. Egg production and hatching success were maximum at 30°C and pH at 7.9. O. rigida preferred the motile green alga Dunaliella salina in terms of ingestion rate, feed selectivity, and egg production across all the temperature and pH conditions. Long-term studies are needed to validate the adaptability of this species to a variety of climate impacts. [ABSTRACT FROM AUTHOR]

Mediterranean endorheic wetlands are strongly affected by local meteorological events, so they undergo frequent unpredictable disturbances, such as episodes of high salinity or desiccation. In this context, salinity and temperature may be crucial for determining the structure of zooplankton communities and regional biodiversity, since they may trigger the hatching of egg bank in different ways. The goal of this study is to assess the combined role of these two variables on the zooplankton assemblage emerging from the egg bank. We hypothesize that temperature and salinity affect the community structure in a non-linear way, that is, both factors interact and modify the magnitude of their effects. We performed a laboratory factorial design where the same sediment was incubated under different thermal and salinity conditions, reducing the potential effects of other possible confusion factors. Community structure was described by measuring cumulative abundances, species composition, richness, and diversity. Our results showed that the community structure was strongly determined by salinity at all experimental temperatures. In contrast, the magnitude of the temperature effect depended on salinity. The high variability among replicates when salinity and temperature increased suggests that climate change might lead to unpredictable patterns of the community emerging from the egg bank. [ABSTRACT FROM AUTHOR]

This research evaluates a semi-automatic incubator designed for hatching quail eggs using locally available materials, with the aim of increasing the quail population, since quails do not naturally incubate their eggs. The objective is to produce meat that competes with broilers as a rich source of protein. The study includes three experimental variables: three incubation temperatures (37, 37.5, and 37.7°C), three turning times (2, 6, and 12 times per day), and three post-hatching periods for chicks to remain in the incubator (2, 6, and 12 hours). The measurements include the percentage of total hatchability within the first 3 hours, as well as rates of deformation and mortality. The results of this research indicated that the manufactured semiautomatic incubator was able to maintain a high hatching percentage, low deformation percentage, and a low mortality percentage when using an incubation temperature of 37.5°C, turning the eggs 12 times per day, and allowing the chicks to stay in the incubator for 12 hours after hatching. Therefore, it is recommended to utilize the manufactured semi-automatic incubator for hatching quail eggs under the above-mentioned parameters. [ABSTRACT FROM AUTHOR]

The impacts that helpers have on offspring in cooperative breeding systems depend on parental responses to help. However, the vast majority of investigations into parental responses to the presence of helpers have considered investment responses during a single phase of breeding—offspring provisioning. Whether or not responses during other phases of breeding complement those during offspring provisioning is therefore unclear. Here, we use temperature probes in model eggs of chestnut-crowned babblers (Pomatostomus ruficeps) to determine: (a) maternal responses to helpers, which (like partners) allofeed incubating females but do not share incubation; and (b) the implications of these responses for egg temperatures. We found that during incubation, increased helper number was associated with longer bouts of incubation interspersed with fewer foraging bouts, which resulted in greater nest attentiveness overall. Further, although helpers had limited effects on average egg temperatures, they were associated with reduced variation in egg temperatures. This reduced variation arose because helpers were associated with higher minimum egg temperatures during off-bouts, presumably because of the negative association between helper number and off-bout number. Together, these results suggest that helpers have additive effects on maternal incubation schedules, which contrasts markedly from the dramatic declines in offspring provisioning shown by mothers with helpers during the nestling phase. Further studies are required to assess the generality of these contrasting patterns and their implications for the quantification of helper effects in cooperative breeders. Significance statement: Maternal responses to the presence of helpers are thought to be species-specific, but most tests are only conducted during offspring provisioning. Using temperature probes in model eggs of cooperative chestnut-crowned babblers (Pomatostomus ruficeps), we show that mothers increase contributions to incubation in the presence of helpers, resulting in more constant egg temperatures. This response contrasts markedly with maternal responses to helper presence during nestling provisioning in this system, suggesting that maternal response rules differ across distinct phases of breeding. [ABSTRACT FROM AUTHOR]

Important for the infection of an insect with an entomopathogenic fungus and its use as a plant protection agent are its growth, conidiation, germination, and virulence, which all depend on the environmental temperature. We investigated not only the effect of environmental temperature but also that of production temperature of the fungus. For this purpose, Metarhizium brunneum JKI-BI-1450 was produced and incubated at different temperatures, and the factors mentioned as well as conidial size were determined. The temperature at which the fungus was produced affects its subsequent growth and conidiation on granule formulation, the speed of germination, and the conidial width, but not its final germination or virulence. The growth and conidiation was at its highest when the fungus was produced at 25 °C, whereas when the germination was faster, the warmer the fungus was produced. The incubation temperature optimum of JKI-BI-1450 in relation to growth, speed of germination, and survival time was 25–30 °C and for conidiation 20–25 °C. Conidial length decreased with increasing incubation temperature. Although the fungus could not be adapted to unfavorable conditions by the production temperature, it was found that the quality of a biological control agent based on entomopathogenic fungi can be positively influenced by its production temperature. [ABSTRACT FROM AUTHOR]

Simple Summary: Ctenolepisma calvum, commonly known as the ghost silverfish, is an insect that lives in buildings, including museums, libraries, and archives. It is regarded as a pest of paper-based objects. Recently, C. calvum was discovered in several areas of Japan for the first time, and it may be a new threat to the conservation of collections that are of cultural and historical importance. Because the biological characteristics of this species in Japan are not well known, we observed their growth and reproduction. We found that eggs were laid from April to November, especially in early June, and eggs usually hatched within two months. The young insects grew through molting, and started laying eggs the next year. Females laid around 10 or more eggs at one time, and they were able to lay eggs once or more per year. Through this study, only females were found, and they were able to reproduce without male individuals. Further research on practical control methods for this species in museums and other facilities is required. Ctenolepisma calvum (Ritter, 1910) (Zygentoma: Lepismatidae) is a primitive wingless insect that causes damage to paper, and it is regarded as a pest of collections in museums, archives, and libraries. This species was recently discovered in Japan for the first time and may have already spread over large areas of Japan, but, currently, no information is available on the biological characteristics of C. calvum in Japan. In this study, we observed the processes of development and reproduction of C. calvum found in Japan at room temperature. Oviposition was observed from April to November, with a peak in early June. The average egg period was 56.9 days at average temperatures above 24.0 °C, and was 72.4 days at average temperatures below 24.0 °C. The 1st, 2nd, and 3rd instars lasted 4.7 days, 13.2 days, and 26.1 days on average, respectively, at average temperatures above 22.0 °C. Average instar periods were 23–28 days in 4th–7th instars and tended to increase in later instars. Instar periods also increased when the average temperature was 22.0 °C or lower. In individual rearing, the longest-living individual lived for approximately two years, up to the 15th instar. The head width grew at an approximate ratio of 1.1 per molt. First oviposition occurred at the 10th or 11th instar. Individually observed females oviposited once or twice a year, laying 6–16 eggs at one time, but females at least two years old laid 78.2 eggs per year on average in a mass-culture cage. Through this study, only females were found, and the mature females produced their progenies parthenogenetically. [ABSTRACT FROM AUTHOR]

[Objectives] This study was conducted to investigate the effects of dietary straw content on the growth and development of oriental migratory locusts (Locusta migratoria), as well as the eefects of temperature and substrate on their egg hatching. [Methods] The eggs of oriental migratory locusts were hatched at 15, 20, 25, 30, 35, and 40 °C in sawdust, soil and sawdust r soil conditions, respectively, to determine suitable environmental conditions for artificial hatching of oriental migratory locusts. Rice straw was added at 0%, 20%, 40%, 60%, 80% and 100% to the basic diet, and the obtained diets was feed to oriental migratory locusts at the 4th instar to investigate the effects on their growth and development. [Results] The eggs of oriental migratory locusts had a good hatching rate at 25 - 30 °C, and sawdust was the best choice for their hatching substrate. Adding 40% of rice straw to the diet could ensure the normal growth and development of oriental migratory locusts while consuming as much rice straw as possible. % Conclusions] This study explored a technical solution for efficiently producing insect protein from discarded crop straw (treating waste with insects' and turning waste into treasure) ' providing support for breeding of oriental migratory locusts and locust disaster prevention. [ABSTRACT FROM AUTHOR]

Systemic inflammatory conditions are often associated with hypothermia or hyperthermia. Therapeutic hypothermia is used in post-cardiac arrest and some other acute diseases. There is a need for more knowledge concerning the effect of various temperatures on the acute inflammatory response. The complement system plays a crucial role in initiating the inflammatory response. We hypothesized that temperatures above and below the physiologic 37 °C affect complement activation and cytokine production ex vivo. Lepirudin-anticoagulated human whole blood from 10 healthy donors was incubated in the presence or absence of Escherichia coli at different temperatures (4 °C, 12 °C, 20 °C, 33 °C, 37 °C, 39 °C, and 41 °C). Complement activation was assessed by the terminal C5b-9 complement complex (TCC) and the alternative convertase C3bBbP using ELISA. Cytokines were measured using a 27-plex assay. Granulocyte and monocyte activation was evaluated by CD11b surface expression using flow cytometry. A consistent increase in complement activation was observed with rising temperature, reaching a maximum at 41 °C, both in the absence (C3bBbP p < 0.05) and presence (C3bBbP p < 0.05 and TCC p < 0.05) of E. coli. Tem p erature alone did not affect cytokine production, whereas incubation with E. coli significantly increased cytokine levels of IL-1β, IL-2, IL-6, IL-8, IFN-γ, and TNF at temperatures > 20 °C. Maximum increase occurred at 39 °C. However, a consistent decrease was observed at 41 °C, significant for IL-1β (p = 0.003). Granulocyte CD11b displayed the same temperature-dependent pattern as cytokines, with a corresponding increase in endothelial cell apoptosis and necrosis. Thus, blood temperature differentially determines the degree of complement activation and cytokine release. • Blood temperature determined the complement activation and cytokine release. • Temperature per se increased complement activation. • Temperature affected cytokine production, when incubated with E. coli. • IL-1β increased maximum at 39 °C and decreased at 41 °C. [ABSTRACT FROM AUTHOR]

Environmental temperature can act as a positive or negative modulator of the physiology and metabolism of poikilothermic organisms. As a general rule, larvae and juveniles are more sensitive to temperature stress than adults, which represents a key factor that partly determines their development and growth in aquaculture. Therefore, this study analyzed the effect of exposure to temperatures of 21, 24, and 27°C on the respiratory metabolism (RM) of Totoaba macdonaldi in different developmental stages. For this purpose, eggs, larvae with 4, 6, 8, 14, and 22 days post-hatch (dph), and juveniles of 25 dph were exposed to the experimental temperatures for 5 h. After the exposure time, oxygen consumption measurements were performed. The results clearly show that temperature (21 to 27°C) has the greatest effect on RM in eggs and larvae at 4 and 22 dph (3.1 ± 0.3 to 4.3 ± 0.3 μmol O2 h-1 egg-1, 2.9 ± 0.3 to 10.5 ± 1.2 μmol O2 h-1 larvae-1 and 102.0 ± 6.4 to 189.8 ± 15.3 μmol O2 h-1 larvae-1, respectively). This thermal sensitivity was not observed from 6, 8, and 14 dph larvae and juveniles at 25 dph, where morphological development was the main factor that influencing the RM. Therefore, this study shows that temperature affects RM in different development stages of totoaba, beginning in the egg stage and intensifying once the larvae hatch until 22 dph. Understanding how temperature affects energy expenditure by measuring RM is essential to establish culture conditions that allow better physiological performance and growth in the early life stages of T. macdonaldi. [ABSTRACT FROM AUTHOR]

Seasonal and geographical adaptations in terms of obligatory embryonic diapause in the parthenogenetic stick insect, Ramulus mikado, were studied. First and second instar nymphs were collected at locations at three latitudes in Japan and reared in the laboratory under a photoperiod of 16L: 8D or 12L: 12D at 25°C. Their eggs were kept at 30°C for 30 or 60 days after oviposition, but no eggs hatched. Hatching was observed more than 100 days after transfer from 30°C to 15°C. The long period between transfer and hatching indicate that eggs in an early embryonic stage of development enter diapause at high-temperatures. The time from oviposition to hatching of eggs laid by adults that originated from the three locations kept under constant conditions between 15 and 25°C were compared. In all these experiments, eggs laid by individuals originating from high latitudes took longer to hatch. The eggs of those originating from Okayama and Ehime did not hatch at 25°C. However, more than 80% of the eggs of those that originated from the northernmost population hatched. Hatching before winter was observed when the eggs of those that originated from the northern population were placed outdoors in Okayama, even when the maternal insects were reared under long-day conditions in the laboratory. These findings indicate that univoltine R. mikado enters diapause twice during embryonic development, which enables it survive adverse conditions in summer and winter, respectively. Furthermore, diapause intensity was lowest in insects that originated from the lowest latitude. [ABSTRACT FROM AUTHOR]

The influence of temperature on sex determination has been reported previously on many crustaceans. The interpretability of temperature capability to regulate the steroidogenic pathway, which in turn governs the offspring sex of mud crab, still remains unclear. Thus, the aim was to determine the effects of temperature on sex percentage and steroidal pathway in purple mud crab, Scylla tranquebarica. In sex percentage analysis, the eggs (28°C and 30°C), larvae (28°C, 30°C and 32°C) and juveniles (26°C, 28°C, 30°C) were exposed to different temperatures. The results revealed that exposure to a higher temperature during larvae (32°C) and juvenile (30°C) stages probably initiated the maleness (58.7%) and femaleness (60.8%) mechanism respectively. In steroid hormone analysis, the eggs (26°C, 28°C, 30°C and 32°C), larvae (29°C, 30°C, 31°C and 32°C) and juveniles (26°C, 28°C, 30°C and 32°C) were exposed to different temperatures. The steroidal assay corroborated the results of the sex percentages, which found higher dihydrotestosterone (172.4 pg/g) and testosterone (580.2 pg/g) levels when the larvae were incubated at a higher temperature (32°C) while higher estrone (136.9 pg/g) and estradiol (540.7 pg/g) levels when the juveniles were reared at high temperature (30°C). In brief, the temperature plays a significant role to redirect the mud crab sex during the larval and juvenile stages. [ABSTRACT FROM AUTHOR]

Eurasian perch is an important fish species for European aquaculture diversification, but the quality of reproduction still remains one of the main limitations for further industry development. In particular, the optimal condition to obtain the best quality of sperm is poorly understood. The aim of our study was to measure the possible effects of two experimental rearing temperatures (6 °C and the conventionally used 12 °C) and of hormonal stimulation, on the motility parameters (pMOT, VCL, VSL, LIN, ALH, BCF), osmolality and fertilizing capacity of Eurasian perch sperm at the end of the reproductive cycle. A prior untested, large-scale (5 mL cryotube and Polystyrene box) cryopreservation method was implemented using fresh sperm obtained from the two above mentioned temperature groups. Males were injected with 100 μg body weight kg−1 sGnRHa. No significant difference was recorded between the two rearing temperatures and between the saline control and sGnRHa treated groups on the different features of sperm quality. A similar fertilization rate was monitored in all sGnRHa treated (6 °C: 69 ± 13%, 12 °C: 81 ± 11%) and saline control groups (6 °C: 79 ± 10%, 12 °C: 87 ± 4%). Correspondingly, no significant difference in hatching rate was observed in the sGnRHa injected (6 °C: 27 ± 9%, 12 °C: 40 ± 20%) and saline control (6 °C: 35 ± 18%, 12 °C: 36 ± 7%) males. However, a notable negative effect of freezing process on sperm movement was observed following thawing in both temperature groups. No significant difference in the motility parameters was measured between the two temperature groups following large-scale cryopreservation. Furthermore, a similar result was observed in the fertilizing capacity (6 °C: 79 ± 10%, 12 °C: 75 ± 8) of thawed sperm as well as in the hatching rate (6 °C: 52 ± 13%, 12 °C: 46 ± 19%). Our results indicate that fresh Eurasian perch sperm can tolerate a reduced rearing temperature following hormonal treatment. The adopted large-scale cryopreservation method could be used efficiently in the future for the fertilization of large amounts of Eurasian perch eggs following a precise standardization process. • No significant difference was recorded between the two rearing temperatures on the different features of sperm quality. • A similar fertilization and hatching rate was monitored in all sGnRHa treated and saline control groups. • No significant difference in the motility was measured between the two temperature groups following cryopreservation. • A similar high fertilization and hatching rate were measured by the two rearing temperatures using cryopreserved sperm. [ABSTRACT FROM AUTHOR]

Campylobacter jejuni is commonly isolated on selective media following incubation at 37 °C or 42 °C, but the impact of these temperatures on genome variation remains unclear. Previously, Campylobacter selective enrichments from the feces of steers before and after ceftiofur treatment were plated on selective agar media and incubated at either 37 °C or 42 °C. Here, we analyzed the whole genome sequence of C. jejuni strains of the same multilocus sequence typing (MLST)-based sequence type (ST) and isolated from the same sample upon incubation at both temperatures. Four such strain pairs (one ST8221 and three ST8567) were analyzed using core genome and whole genome MLST (cgMLST, wgMLST). Among the 1970 wgMLST loci, 7–25 varied within each pair. In all but one of the pairs more (1.7–8.5 fold) new alleles were found at 42 °C. Most frameshift, nonsense, or start-loss mutations were also found at 42 °C. Variable loci CAMP0575, CAMP0912, and CAMP0913 in both STs may regularly respond to different temperatures. Furthermore, frameshifts in four variable loci in ST8567 occurred at multiple time points, suggesting a persistent impact of temperature. These findings suggest that the temperature of isolation may impact the sequence of several loci in C. jejuni from cattle. [ABSTRACT FROM AUTHOR]

The analytical stability of laboratory tests relies mostly on internal and external quality control procedures. Summarized patient data has in several studies been shown to be a good supplement for monitoring analytical stability. In our present investigation, we evaluate a datamining method for retrospective evaluation and assessment of analyte stability in whole blood. Results from the laboratory information system were used as the basis for the datamining approach. Blood tests were requested by the general practitioners and drawing of the blood sample was either at the general practitioner's or at the hospital outpatient clinics. We were able to split data into groups based on sample collection place and time to analysis. The datamining approach was compared to experiments where samples were incubated at a single temperature as well as an experiment where the temperatures were changed during incubation. To demonstrate the method, we selected three laboratory tests considered representative: potassium, phosphate, and lactate dehydrogenase. The datamining approach showed results similar to the reference experiment. Furthermore, our results show that the analytes phosphate and potassium were not stable after short storage at a lower temperature. [ABSTRACT FROM AUTHOR]

Prawns are commercially one of the most important marine resources. However, in their early developmental stages, they face challenges related to physico-chemical and environmental changes. This study aimed at investigating the effects of temperature and salinity on egg incubation time, hatching success, larval and postlarval survival of the giant tiger prawn, Penaeus monodon (Fabricius 1798) obtained from the coastal waters of Tanzania. The adult females P. monodon collected off Rufiji delta were left to acclimatize and spawn at 28.5 ± 0.5 °C and 32 ppt in the hatchery. Spawned eggs were incubated at experimental temperatures of 27 °C, 31 °C and 35 °C with three subgroups of salinities of 30 ppt, 35 ppt and 40 ppt. The incubation time was longest (15.2 hours) at 27 °C and 30 ppt, and shortest (10.7 hours) at 35 °C and 40 ppt. Hatching success was highest (85.2%) at 31 °C temperature and 30 ppt salinity, and lowest (69.45%) at 35 °C and 40 ppt. Larval and postlarval survival was suitable at 27-31 °C and 30-35 ppt. These findings suggest that optimum rearing temperature and salinity for P. monodon range 27-31 °C and 30-35 ppt, respectively. Changes in temperature and salinity above the optimum range may jeopardize the hatching and subsequent survival of P. monodon especially at their early developmental stages which are more sensitive to environmental changes. [ABSTRACT FROM AUTHOR]

Interest in the production of crustacean aquaculture has focussed primarily on mud crab species; however, mud crab production still relies on wild‐caught juveniles due to the low production of viable seeds of mud crab. Thus, the aim of this study was to enhance mass propagation of purple mud crab seed by studying the relation of temperature on growth performance of the early life stage of purple mud crab. Several data such as survival, incubation duration and morphometric measurements were evaluated after temperature was exposed on the egg, larval and crablet stages. For the egg stage, high hatching success (78.95% and 75.00%) was noted within a limited temperature range (28°C and 30°C respectively). Also, significant increment of final egg diameter (0.33 ± 0.05 mm) after the berried crab incubated at 30℃. For larval stage, the highest survival rate was found when the larvae were reared at 30℃ and 31°C with 68.79 ± 2.69 and 66.98 ± 2.63% respectively. The largest morphometric measurements for megalopa (CW: 2.80 ± 0.15 mm) and C1 (CW: 2.86 ± 0.12 mm) were observed at 31℃. The yielded total juvenile at the end of the larval experiment indicated the highest production was obtained for temperature 31°C (1,095 ± 47.3 individuals) followed by 30°C (1,002 ± 84.7 individuals). For the crablet stage, the crablets were able to survive in a wide range of temperatures (26°C–32°C) with >95% survival; however, the temperature 26℃–29°C indicated larger morphometric measurements (CW: 6.24–6.39 mm). In brief, the optimal temperature for egg, larval and crablet stages was recommended within 28℃–30℃, 30℃–31℃ and 26℃–29℃ respectively. [ABSTRACT FROM AUTHOR]

Embryonic vocalizations in birds may enable communication between embryos and incubating parents but responses of parents to embryonic vocalizations have not been measured experimentally. In two ground‐nesting shorebirds, we compare parental care of eggs without embryonic vocalizations, those with natural embryonic vocalizations, and those in which we experimentally introduced embryonic vocalizations, while accounting for prevailing temperatures. We continuously recorded nests (one block of up to 24 h per nest) of two ground‐nesting shorebirds, the Red‐capped Plover Charadrius ruficapillus and Masked Lapwing Vanellus miles and quantified parental behaviours. We predict an increase in egg thermoregulation behaviours (time spent incubating or shading) and 'fussing' (a combination of rising and re‐settling, shuffling, orientation change and egg turning) when vocalizations were naturally present or when they were experimentally introduced in comparison to when no vocalizations were present (control). In Lapwings, the rate of fussing increased at the nest only when natural vocalizations were present; however, preening increased when natural or introduced vocalizations were present. Additionally, the frequency of bill to egg touches (inspections) increased only in the presence of introduced vocalizations. For Plovers, treatment had no influence on parental behavioural; however, the frequency of fussing, bill to egg touches and shell tossing increased with air temperature. For both species, there was no influence of the presence of the embryo's vocalizations (natural or introduced) on the parent's egg thermoregulation behaviours. Our results highlight that acoustic communication across the eggshell may occur and can influence parental care in shorebirds, but this appears to be species‐specific. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the optimum temperature and salinity for the hatching rate, hatching time of eggs and larval activity of Farfantepenaeus aztecus (Ives, 1891). For this purpose, F. aztecus, which was caught from nature in the 4th gonad stage and were spawned on the same night in controlled laboratory conditions. The eggs were stocked in 2-l round bottom glass flasks and received one of nine temperature (24, 28 and 32°C) and salinity (30, 35 and 40 ppt) combinations as 50 eggs per liter after determining the fertility rate of the eggs. Although eggs hatched in all salinity and temperature combinations, water temperature, salinity and interaction had significant effects on hatching rate, hatching time and larval activity (P<0.05). Considering only salinity, the best hatching ratio was found at 35 ppt (48.44%), 40 ppt (47.89%) and the lowest hatching rate was found at 30 ppt (34.77%, P<0.05). It was found that the best hatching ratios were at 28°C (52.22%), at 32°C (48.33%) and followed by the eggs incubated 24°C (30.55%, P<0.05). The incubation time was shortened due to the increase in water temperature and changed between 11.40-17.10 hours. It was determined that the activities of the larvae incubated at lowest water temperature (24°C) and at 30 ppt were weaker than those incubated at 28°C and 35-40 ppt salinities. The results show that 28-32°C water temperature and sea salinity slightly less than the salinity of the Mediterranean Sea (38.5 ppt) are optimal for the incubation eggs and for the production of high quality nauplii of F. aztecus found in the Northeastern Mediterranean. [ABSTRACT FROM AUTHOR]

In this study, fermentation strategies were carried out for improving the production of bacteriocin-like inhibitory substances by Lactobacillus brevis C23 with nutrient supplementation, pH, and temperature variations, as well as fed-batch cultivation. The BLIS activity was highest (91.52%) in the MRS medium supplemented with 1.5% (w/v) lactose and 1% (w/v) meat extract. pH 5 augmented both the cell biomass and BLIS activity, but incubation temperature only affected growth at 37°C. Fed-batch cultivation strategy that utilized meat extract feeding would positively affect cell growth, whereas BLIS activity was enhanced by lactose feeding. The highest BLIS activity from L. brevis C23 was obtained at the 24 hr mark by feeding the culture medium with lactose (77.73%). The BLIS production of L. brevis C23 fed with meat extract followed a similar trend to lactose (74.20%). Increased BLIS activity in the final solution would reduce the downstream step such as concentrating the purified product. Novelty impact statement Synergic effect of lactose and meat extract enhanced BLIS activity (91.52%) of CFS by Lactobacillus brevis C23 as compared to the control (69.29%) Temperature at 40℃ did not affect the BLIS activity, but it inhibited the cell growth. Fed-batch cultivation strategy that utilized meat extract feeding would positively affect cell growth, whereas BLIS activity was enhanced by lactose feeding. [ABSTRACT FROM AUTHOR]

Studies in Evo‐Devo benefit from the use of a variety of organisms, as comparative approaches provide a better understanding of Biodiversity and Evolution. Standardized protocols to incubate eggs and manipulate embryo development enable postulation of additional species as suitable biological systems for research in the field. In the past decades, vertebrate lineages such as Squamata (lizards, snakes, and amphisbaenians) emerged as crucial study systems for addressing topics as diverse as phenotypic evolution and climate change. However, protocols for maintaining gravid females and incubating eggs in the lab under experimental conditions are available to only a few squamate species. This resource article presents a simple incubation guide that standardizes conditions to maintain embryos of Tropidurus catalanensis (Squamata: Tropiduridae) under different experimental conditions, manipulating relevant environmental factors like temperature and humidity. We identified associated effects relating the egg incubation condition to developmental stage, incubation time, hatching success, and resulting morphotypes. Temperature and humidity play a key role in development and require attention when establishing the experimental design. Current literature comprises information for Tropidurus lizards that ponders how general in Squamata are the ecomorphs originally described for Anolis. Studies evaluating phenotypic effects of developmental environments suggest plasticity in some of the traits that characterize the ecomorphological associations described for this family. We expect that this incubation guide encourages future studies using Tropidurus lizards to address Evo‐Devo questions. Research Highlights: We provide a guide to incubate embryos of Tropidurus lizards under different experimental conditions, accessing the effects of developmental environments on hatching success, developmental rates, and neonate phenotypes. [ABSTRACT FROM AUTHOR]

An egg of the critically endangered flapper skate Dipturus intermedius was successfully incubated to hatching in captivity in what is believed to be a first for the species. Water conditions (temperature, salinity, flow rate) were recorded, with mean water temperatures ranging from a monthly mean of 8.3 ± 1.2 to 13.2 ± 0.3°C and salinity from a monthly mean of 30.5 ± 1.2 to 36.6 ± 2.3 ppt. Hatching occurred after 534 days, suggesting that flapper skate eggs take c. 5700 growing degree‐days to incubate to hatching. The egg's prolonged embryonic development raises concerns about flapper skate eggs' vulnerability to anthropogenic disturbance. [ABSTRACT FROM AUTHOR]

1. The effect of breeder flock age, storage temperature and a short period of incubation during egg storage (SPIDES) on albumen quality, development of blastoderm, and hatchability of long-stored eggs was evaluated. 2. Hatching eggs were collected from 28-week-old (young) and 40-week-old (prime) Ross female line grandparent flocks and were stored for 14 d at 12, 15 or 18°C. During storage, the eggs were either kept continuously in the storage room (control) or were subjected to SPIDES treatment. 3. Embryonic development was more advanced in eggs from the prime flock, exposed to SPIDES and warmer (18°C) storage temperature (P ≤ 0.05). There was a difference in the albumen pH for flock ages (P < 0.05), but the SPIDES treatment did not affect albumen height and pH (P > 0.05). On d 14 of storage, albumen pH was positively (P < 0.05) correlated with storage temperature. Hatchability was higher in the prime flock (P < 0.05). 4. At both flock ages, hatchability increased (P < 0.05) by storing the eggs at 15°C, compared to 18°C, with 12°C intermediate. The hatchability improvement was due to reduced early embryonic mortality. 5. The SPIDES treatment decreased late embryonic mortality and the percentage of second-grade chicks (P < 0.05), which increased the hatchability of fertile eggs (P < 0.05). SPIDES only reduced (P < 0.05) early embryonic mortality in eggs stored at 18°C. 6. The highest hatchability was observed in the eggs stored at 15°C and exposed to one SPIDES treatment during 14 d storage. [ABSTRACT FROM AUTHOR]

The pink stem borer, Sesamia cretica Lederer is considered as the main insect pest of maize and sugarcane worldwide. Reproductive and life table parameters of two populations of S. cretica were studied at 10 constant temperatures ranging from 12 to 36 (±1)°C, 50 ± 10% RH and a photoperiod of 0:24 (L:D) h for the larval stage and 16:8 (L:D) h for the other stages. At 12°C, no eggs hatched and at 15, 35, and 36°C only the incubation period was completed. The longest (135.81 and 156.49 d) and shortest (49.61 and 52.09 d) female life span were observed at 20 and 32°C for the Varamin and Rey populations, respectively. The highest (181.66 and 180.94 eggs/female) and lowest (13.40 and 32.85 eggs/female) total fecundity of the Varamin and Rey populations were found at 20°C and 34°C, respectively. At the same time, these two populations had the highest intrinsic rate of increase (r) (0.0343 and 0.0349 d-1) at 30 and 27°C, respectively. Similarly, both Varamin and Rey populations had the highest finite rate of increase (λ) at 27°C (1.0349 and 1.0355 d-1, respectively). It was found that the geographical populations of S. cretica were different in terms of the life table parameters at the same temperatures, and this issue can affect the results of forecasting studies. Accordingly, it is suggested that in the major corn-growing areas, a comprehensive study should be performed on different pest populations to address their commonalities and differences for future managing programs. [ABSTRACT FROM AUTHOR]

Avian embryos need a stable thermal environment to develop optimally, while incubating females need to allocate time to self‐maintenance off the nest. In species with female‐only incubation, eggs are exposed to ambient temperatures that usually cool them down during female absences. The lower the ambient temperature the sooner females should return to re‐warm the eggs. When incubation constraints ease at increasing ambient temperatures, females respond by increasing either incubation effort or self‐maintenance time. These responses are population‐dependent even within the same species; but it is uncertain whether they are caused by local environmental conditions or they are an artefact from limited datasets, different methodological approaches or the timescale over which incubation behaviour is measured. In this study, we collected incubation data from three Mediterranean great tit Parus major populations during three consecutive years. We measured the duration of each off‐ and on‐bout event, used these variables to compute nest attentiveness at three different timescales (full incubation, daily and hourly periods) and assessed the impact of ambient temperature on bout duration and nest attentiveness. We found that females maximized on‐bout duration at different local temperatures, ranging from 10 to 20°C; but lengthened off‐bouts linearly across a range of 0–38°C in all three populations. These local differences translated into opposite linear nest attentiveness patterns at the full incubation scale: Females increased either incubation effort, longest on‐bouts between 15 and 20°C or self‐maintenance time, longest on‐bouts at 10°C. It was at daily and hourly periods when we detected non‐linear nest attentiveness patterns, as expected from on‐bout duration, peaking at different local ambient temperatures. Females first increased incubation effort up to a certain temperature value and then increased self‐maintenance time at the highest ambient temperatures. Further research is needed to understand which factors are behind the turning points from one behaviour to the other. [ABSTRACT FROM AUTHOR]

Effect of extended storage on egg quality, embryo mortality and hatchability in FUNAAB-α chickens was determined. Hatchable eggs (n = 288; weighing 53.2 ± 4.67 g) collected from a flock of FUNAAB-α layer breeder hens aged 32 weeks were stored in egg tray with broad end up under 16 ± 1.5°C for either 0, 4, 8, 12, 16 or 20 d. Before incubation, eight eggs from each group were evaluated for internal and external quality traits. Remaining eggs were set in an incubator and transferred into hatcher on embryonic day 18. Data collected were subjected to one-way analysis of variance. Egg weight loss (EWL; p < .001), surface area (p < .001), yolk diameter (p < .001), inner and outer blastoderm diameters (p < .05) and dead in germ (DIG; p < .001) increased with storage duration while yolk height (p < .001), y olk i ndex (p < .001), albumen weight (p < .05), albumen height (p < .05), albumen index (p < .01), Haugh's unit (HU; p < .05), fertility (p < .001), hatchability of set (HATCHS; p < .001) and fertile eggs (p < .05) decreased. Weight losses of 0, 1.2, 2.2, 3.4, 4.6 and 6.1% were recorded in egg stored for 0, 4, 8, 12, 16 and 20 days respectively. Eggs stored beyond 8 days exhibited higher DIG and lower HATCHS. Shell percentage in 4 days storage (11.4%) was lower (p < .05) than in 16 days storage (13.4%). Shell thickness was similar in eggs stored for 0 to 12 days, but 8 days storage (0.60 mm) had thinner (p < .01) shell than day 16 (0.71 mm) and day 20 (0.73 mm) storage. Internal quality unit (IQU) was higher (p < .05) in fresh eggs (180.4) than in 12 days (167.8) and 20 days (167.8) stored eggs. Extended storage of FUNAAB-α eggs caused EWL, surface area shrinkage, lowered HU and IQU, loss of yolk and albumen quality, increased blastoderm diameters and DIG, and decreased egg fertility and HATCHS from day 8 forward. Storing FUNAAB-α eggs beyond 8 days reduced quality parameters; therefore, other mitigating factors are recommended when storing beyond 8 days. [ABSTRACT FROM AUTHOR]

Climate change and associated changes in weather patterns have globally widespread effects on natural systems. Shifts in phenology can affect the reproductive success of birds by causing a mismatch between the onset of breeding and favourable conditions for reproduction, such as a peak in food availability. Weather conditions and their changes have also long been discussed as affecting the reproductive success of grouse (Tetraoninae) and contributing to rapid declines in many central European populations. We monitored the reproductive success of Western Capercaillie Tetrao urogallus in the Black Forest, Germany, over a 14‐year period to study how weather conditions correlated to reproductive success and to assess whether changing environmental conditions were related to a seasonal shift in reproduction. We observed a temporal shift in peak lekking activity from late to mid‐April, which corresponds to an advance of 0.65 days/year. Furthermore, we show that warm conditions during the reproductive season were positively associated with reproductive success (i.e. larger brood size, more hens with chicks and more chicks per hen) and that precipitation volume during the early weeks after hatching was negatively correlated with brood size. Precipitation before copulation (i.e. peak of lekking) affected the proportion of hens with chicks and the number of chicks per hen. Sex ratio in broods was also affected by weather conditions, with more female than male chicks in years with low temperatures and high precipitation. By analysing spring weather predictions for the period 2020–2039, we found that weather conditions during the reproductive period remained constant when assuming a continued advancement of reproduction onset, although annual variation was high. We show the importance of weather conditions in influencing Western Capercaillie reproductive success. Western Capercaillie in the Black Forest seem to adjust the timing of reproduction according to changes in weather conditions, but this advancement is unlikely to be limitless, making the future impact of climate change on the species uncertain. [ABSTRACT FROM AUTHOR]

In birds, ambient temperature can influence adult incubation behaviour, energy budget, egg temperature and embryonic development, with downstream effects on offspring survival. Surprisingly, experimental manipulations of the whole nesting environment to test causes and consequences of variation in incubation pattern, energy balance, egg temperature and the duration of development are lacking to date. Here, we bred pairs of Zebra Finches Taeniopygia guttata under controlled conditions at 18 and 30 °C and measured clutch size, temperature, hatching success, parental attentiveness and the length of the embryonic period. We found that when breeding at the higher temperature, males, but not females, increased the number of incubation bouts on the nest. Instead, females, but not males, reduced their attentiveness towards the clutch overall. Eggs showed no temperature differences between the two treatments and bigger clutches experienced lower temperatures. This suggests that parental behaviour may buffer the effect of ambient conditions on the thermal profile of eggs, including species with high rates of parental attentiveness. Warmer conditions yielded higher hatching rates but did not cause measurable differences in the length of embryonic development. Still, smaller clutches hatched earlier in accordance with the higher temperature experienced. Additionally, we used data from the literature to calculate parental energy expenditure and demonstrate that this was substantially different across the two treatments, although predicted energy savings from reduced attentiveness at 30 °C appeared negligible. These results suggest that when food is available, ambient temperature and not energy trade‐offs may explain variation in incubation behaviour. [ABSTRACT FROM AUTHOR]

In fishes, differences in early rearing environment can have a significant impact on phenotypic development. In the present study, we examined the effect of differences in egg incubation (adhered to substrate or non-adhered and tumbled) and water temperature during early rearing on the development of escape response and volitional swimming performance in lake sturgeon, Acipenser fulvescens, throughout the first year of life. Developing embryos were incubated at 12–14 °C and supplied with flow-through aquarium water and ambient light conditions in McDonald hatching jars or allowed to adhere to substrate. Upon hatch (~ 9 days post-fertilisation, dpf), larvae from each incubation treatment were then acclimated to 16, 18 or 20 °C at a rate of 0.5 °C·day−1 and held at those temperatures until approximately 33 dpf. All treatments were then transferred to a common garden experiment where tanks were fed flow-through river water at ambient temperature and natural light cycles. Sturgeon were fed ad libitum twice daily throughout the growing season and food was withheld when water temperature reached 1.5 °C (~ 6 months post-hatch). Food was reintroduced at the start of spring the following year when water temperature exceeded 2 °C (~ 10.5 months post-hatch). There was no consistent effect of treatment on either volitional swimming or escape responses suggesting significant phenotypic plasticity in these measured traits during the first year of life. There was however an effect of time on these performance metrics that was most likely the result of seasonal differences in temperature throughout the 13-month study. [ABSTRACT FROM AUTHOR]

Background: The thermal-manipulation (TM) during egg incubation is a cyclic exposure to hot or cold temperatures during embryogenesis that is associated to long-lasting effects on growth performance, physiology, metabolism and temperature tolerance in birds. An increase of the incubation temperature of Japanese quail eggs affected the embryonic and post-hatch survival, growth, surface temperatures and blood characteristics potentially related to thermoregulation capacities. To gain new insights in the molecular basis of TM in quails, we investigated by RNA-seq the hypothalamus transcriptome of 35 days-old male and female quails that were treated by TM or not (C, control) during embryogenesis and that were exposed (HC) or not (RT) to a 36 °C heat challenge for 7 h before sampling. Results: For males, 76, 27, 47 and 0 genes were differentially expressed in the CHC vs. CRT, CRT vs. TMRT, TMHC vs. TMRT and CHC vs. TMHC comparisons, respectively. For females, 17, 0, 342 and 1 genes were differentially expressed within the same respective comparisons. Inter-individual variability of gene expression response was observed particularly when comparing RT and HC female animals. The differential expression of several genes was corroborated by RT-qPCR analysis. Gene Ontology functional analysis of the differentially expressed genes showed a prevalent enrichment of terms related to cellular responses to stimuli and gene expression regulation in both sexes. Gene Ontology terms related to the membrane transport, the endoplasmic reticulum and mitochondrial functions as well as DNA metabolism and repair were also identified in specific comparisons and sexes. Conclusions: TM had little to no effect on the regulation of gene expression in the hypothalamus of 35 days-old Japanese quails. However, the consequences of TM on gene expression were revealed by the HC, with sex-specific and common functions altered. The effects of the HC on gene expression were most prominent in TM females with a ~ 20-fold increase of the number of differentially expressed genes, suggesting that TM may enhance the gene response during challenging conditions in female quail hypothalamus. TM may also promote new cellular strategies in females to help coping to the adverse conditions as illustrated by the identification of differentially expressed genes related to the mitochondrial and heat-response functions. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity and local adaptation are viewed as the main factors that result in between-population variation in phenotypic traits, but contributions of these factors to phenotypic variation vary between traits and between species and have only been explored in a few species of reptiles. Here, we incubated eggs of the Chinese skink (Plestiodon chinensis) from 7 geographically separated populations in Southeast China at 3 constant temperatures (24, 28, and 32 °C) to evaluate the combined effects of clutch origin, source population, and incubation temperature on hatchling traits. The relative importance of these factors varied between traits. Nearly all examined hatchling traits, including body mass, snout–vent length (SVL), tail length, head size, limb length, tympanum diameter, and locomotor speed, varied among populations and were affected by incubation temperature. Measures for hatchling size (body mass and SVL) varied considerably among clutches. Source population explained much of the variation in hatchling body mass, whereas incubation temperature explained much of the variation in other examined traits. Our results indicate that between-population variation in hatchling traits of P. chinensis likely reflects the difference in natural incubation conditions and genetic divergence. [ABSTRACT FROM AUTHOR]

In this study, the effects of temperature on the growth, development, survival, fecundity and other population parameters of two local Bradysia species B. odoriphaga and B. impatiens were studied at four constant temperatures (25, 28, 31 and 34°C). The results show that 25°C is the optimum temperature for the growth and development of B. odoriphaga, while 28°C is more favourable for B. impatiens. The temperature of 31°C restricted the growth and development, while the temperature of 34°C inhibited the eggs hatching in both species, resulting in no egg survival and no subsequent development. High temperatures (>28°C) prolonged the 4th larval stage duration, mean generation time (T) and population doubling time (Dt) of both species. The high temperature of 31°C greatly shortened the female longevity, weakened the oviposition and reduced the survival of both species. Moreover, the life table parameters R0, rm and λ were also suppressed by this high temperature. However, the high temperature of 31°C had little impact on the egg survival, pupal weight and male longevity. In addition, at 31°C, the values of R0, rm and λ of B. odoriphaga were higher than those of B. impatiens, suggesting that B. odoriphaga is more tolerant to high temperature than B. impatiens. The differences between two Bradydsia species seem determined genetically. Our findings are important for better understanding their biological characteristics at a certain constant temperature and demonstrate the possibility to control and manage those two Bradysia species by increasing ambient temperature. [ABSTRACT FROM AUTHOR]

Elucidating factors that limit the number of offspring produced is fundamental to understanding life‐history evolution. Here, we examine the hypothesis that parental ability to maintain an optimal physical developmental environment for all offspring constrains clutch size via effects on offspring quality.Experimental laboratory studies of birds have shown that a <1°C difference in average incubation temperature has diverse effects on fitness‐related post‐hatching offspring phenotypes. Thus, the inability of parents to maintain optimal incubation temperatures could constrain clutch sizes.A fundamental question that has not been sufficiently addressed is whether larger clutch sizes lead to within nest variation in egg temperature that is large enough to produce offspring with different phenotypes within a brood. This could lead to differential survival among offspring, and could create a trade‐off between offspring number and quality.We manipulated clutch size in nests of free‐living wood ducks and measured incubation temperature among and within clutches using multiple temperature loggers.As clutch size increased, average incubation temperatures were lower and more variable, and eggs took longer to hatch. Notably, the range in average incubation temperature among eggs within nests increased with clutch size and exceeded 1°C in large clutches. Clutch size did not affect hatch success.In conjunction with our companion laboratory studies that used artificial incubation to document the effects of temperature variation on fitness‐related traits in this species, our work suggests that suboptimal incubation temperatures could be a factor that limits clutch size through diminishing returns on post‐hatch offspring quality. A free plain language summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Comparisons were made of the effects of temperature and duration of low temperature on hatch of newly laid egg masses of the invasive spotted lanternfly, Lycorma delicatula (White). Egg masses were collected in mid-October 2019 and estimated to be less than 14 d old. There was a significant positive nonlinear relationship between temperature and developmental rate (1/d) for eggs held at constant temperatures. The lower threshold for egg development was estimated as 7.39°C. Eggs held at constant 10, 15, and 20°C were estimated to require 635, 715, and 849 DD7.39, respectively, to develop. Egg hatch was variable, egg hatch rates were highest (58.4%) when held at a constant 15°C, though high rates (52.7%) were also obtained when eggs were held for 84 d at 10°C, then moved to 25°C. Almost all eggs enter diapause since very few eggs were able hatch when moved to 25°C after 7 d of chill at either 5 or 10°C. Chilling at 5 or 10°C increased percentage egg hatch as the duration in chill increased up to ~100 d and eggs held at 10°C were able to complete some or all the post-diapause development before being moved to 25°C. All egg masses were held at constant 16:8 (L:D) photoperiod and 65%RH. Our data suggest that temperature is the driving factor for diapause termination in spotted lanternfly, but other abiotic factors should be investigated. These identified developmental temperature threshold and degree day requirements for egg hatch will improve predictive distribution and phenological models. [ABSTRACT FROM AUTHOR]

The hatching of fairy shrimp Branchinella thailandensis from Thailand was studied. The fairy shrimp cysts were subjected to different temperature regimes [ambient (26-29oC), 30°C, 32°C, and 34°C] and examined the experimental condition's effect on hatching until no hatching occurred. Results indicated that temperature affects the hatching of the Thai fairy shrimp B. thailandensis cysts. The hatching of the fairy shrimp could occur once at 34oC and can be stimulated at 32oC, but fluctuating temperatures (26-29oC) and 30oC may reduce hatching success. However, the incubation period took longer, and hatching success was extremely low, suspected of improper cysts production technique and processing. In conclusion, the hatching of fairy shrimp B. thailandensis can be improved at 34oC but optimal at 32oC. [ABSTRACT FROM AUTHOR]

Agasicles hygrophila, a leaf-feeding Chrysomelid beetle, was introduced into China in 1986 as a biological control for Alternanthera philoxeroides (alligatorweed), a noxious perennial invasive weed. However, Hunan's Ag. hygrophila populations decrease suddenly during summers (at high temperatures), leading to the inefficient control of alligatorweed. To investigate this phenomenon, herein, the effects of four different temperatures (26, 30, 36, or 39°C) on the reproductive capacity and egg-hatch, pupation, eclosion, and adult survival rates of Ag. hygrophila were explored. The effects of four different durations of each temperature treatment (4, 8, 12, or 16 days) were investigated. All the studied parameters were significantly affected following each of the four temperature and time treatments. At 30°C, the egg-hatch, pupation, and eclosion rates were considerably lower than those in the control group at 26°C. However, there were no significant differences in the number of eggs laid and the adult survival rates. Heat-shock at 36°C and 39°C led to significant decreases in the number of eggs laid, and the egg-hatch, pupation, eclosion, and adult survival rates compared to those at 26°C. Furthermore, high temperature had the greatest effect on Ag. hygrophila pupae, and the eclosion rate was close to zero; this may have caused the sharp decrease in the Ag. hygrophila population. The results will help better understanding the impact of biological control on Al. philoxeroides during summer temperatures and will also support optimization of biocontrol strategies, notably for the release of biocontrol agents across different geographical regions with different climates. [ABSTRACT FROM AUTHOR]

Constant and oscillating egg incubation temperatures on embryonic development and early larval morphology were studied in longfin yellowtail (Seriola rivoliana Valenciennes). We investigated the effects of constant temperatures from 16 to 32°C on embryo development and larval morphology at hatch, and whether oscillating temperature during embryogenesis could lead to larval morphological variations. After hatching, larval morphology and development during yolk sac (YS) utilization were examined in larvae at constant temperatures and larvae at 25°C that had oscillating temperature during egg incubation. Hatching rates were > 75%, only decreasing to ~ 50% at 30°C. At constant temperatures, the largest larvae occurred at 22 and 24°C. The oscillating temperature did not affect the timing of embryo development but resulted in larger and smaller larvae with a smaller and bigger YS, respectively, with a similar hatching time. Therefore, a growth response occurred in embryos during a window of development before hatching, depending on the adaptive response to temperature (spawn‐specific). After hatching, most of the YS was absorbed within 24 hr in all treatments, and the growth of the larval head was a priority with an optimal development at 26°C. There was compensatory growth in smaller larvae resulting in similar sizes after YS utilization, but larvae showed variations in body structure that could be important in further aquaculture research. [ABSTRACT FROM AUTHOR]

This research paper presents the design, construction, and performance testing of an automatic electrically powered egg incubator utilizing the horizontal placement of eggs. This experimental research was driven by the specific design and construction of a well-insulated rectangular egg-incubating box of dimension 400 mm × 600 mm × 500 mm and thickness 30 mm, where sample eggs were kept for experimental test analysis under the favorable temperature and humidity inside the box, which was automatically controlled. The device was made to operate under the temperature range of 37°C - 38°C, which was found to be adequate for developing embryos and also maintaining relative humidity at the range of 45-60% for the first 18 days and 60-90% for the last three days. Finally, in this machine, the egg tray was adjusted horizontally, and a motor clamped mechanism was used 5 times a day which was controlled automatically by a micro-controller for the motion of eggs up to 18 days of incubation. In conclusion, this egg-incubating machine has an efficiency and hatchability of 72.22%. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the survival of Rhipicephalus microplus females under low temperature, to determine the influence of temperature and relative humidity (RH) on the biological parameters of this tick. In total 300 viable engorged female ticks collected from cattle were used. On the day of collection (D0), 30 female ticks were divided into three groups: G1, kept at 28 °C and 80% RH; G2, kept at 20 °C and 80% RH; and G3, kept at 20 °C and 30% RH. The remaining females were stored in a refrigerator at 4 °C. Over the next 9 days (D+1 to D+9), 30 female ticks were removed daily from the refrigerator and distributed among the three treatments. Egg mass, feed conversion rate, egg incubation period, larval hatch rate, number of dead females per group, weight of female tick removed from the refrigerator, and female tick weight loss were recorded. At 20 °C and 80% RH hatching was delayed. Among the female ticks kept in the refrigerator and then allocated to groups G1, G2, and G3, there was a reduction in reproductive efficiency and a rise in mortality as time in the refrigerator increased. The female ticks expressed their best reproductive capacity when subjected to the refrigeration temperature for a maximum of 3 days and then kept at 28 °C and 80% RH. Thus, although female ticks can be stored in the refrigerator before being sent to research centers for use in bioassays, the storage time should be as short as possible, not exceeding 3 days. [ABSTRACT FROM AUTHOR]

Climate change plays a key role in the development and survival of oviparous ectotherms such as sea turtles. Higher environmental temperatures are expected to lead to increased production of female hatchlings and potential feminization of many populations, as well as reduced hatching success and hatchling fitness. We investigated how different sand temperatures affect sea turtle embryo mortality, hatchling phenotype, and hatchling predation during their crawl to the sea. The study was conducted in Cabo Verde, the only rookery of the endangered loggerhead turtle (Caretta caretta) in the Eastern Atlantic. During three consecutive seasons (2015–2017), 240 loggerhead clutches were exposed to three different incubation temperature regimes created by different sand colours. The warm treatment (mean = 32.3 °C ± 0.5) killed 33% more embryos than the cold treatment (mean = 29.7 °C ± 0.6). Hatchlings from the warm treatment were mostly females, smaller in size, and had lower performance. Hatchling predation by ghost crabs during seaward transit was higher for hatchlings incubated in the warm treatment. Combining embryo mortality and hatchling predation, the rate of female hatchling arrival at the sea was more than twice as high in the cold treatment (34.4 females per 100 eggs) than in the warm treatment (16.0 females per 100 eggs). This increase in mortality caused by warmer incubation temperatures may cancel any potential benefit of a female-biased sex ratio. Conservation planners should consider behavioural adaptations and the potential dispersal of the nesting areas to colder areas to increase resilience of loggerhead turtles to climate change. [ABSTRACT FROM AUTHOR]

The effect of incubation and rearing temperature on muscle development and swimming endurance under a high‐intensity swimming test was investigated in juvenile Chinook salmon (Oncorhynchus tshawytscha) in a hatchery experiment. After controlling for the effects of fork length (LF) and parental identity, times to fatigue of fish were higher when fish were incubated or reared at warmer temperatures. Significant differences among combinations of pre‐ and post‐emergence temperatures conformed to 15–15°C > 15–9°C > 9–9°C > 7–9°C > 7–7°C in 2011 when swimming tests were conducted at 300 accumulated temperature units post‐emergence and 15–9°C > (7–9°C = 7–7°C) in 2012 when swimming tests were conducted at an LF of c. 40 mm. The combination of pre‐ and post‐emergence temperatures also affected the number and size of muscle fibres, with differences among temperature treatments in mean fibre cross‐sectional area persisting after controlling for LF and parental effects. Nonetheless, neither fibre number nor fibre size accounted for significant variation in swimming endurance. Thus, thermal carryover effects on swimming endurance were not mediated by thermal imprinting of muscle structure. This is the first study to test how temperature, body size and muscle structure interact to affect swimming endurance during early development in salmon. [ABSTRACT FROM AUTHOR]

Introduction: Sea turtles have temperature dependent sex determination. The increase in global temperature leads to higher nest temperatures that can cause a prevalence of females, threatening the future of these species. Objective: The present work aims to evaluate the trend of incubation temperatures and the incubation period, as well as to estimate the sex ratio in nests of Chelonia mydas at Antonio and La Barca beaches, Southwestern Cuba, during the seasons from 2012 to 2018. Methods: Temperature data loggers were placed in green turtle nests with a representativeness that varied between the years analyzed. To assess the temporal variation of temperatures and incubation periods, a Kruskal-Wallis test was performed in each case. Sex ratio was estimated from its relation with temperature and incubation duration. Results: At La Barca beach, there was a 1.5 °C increase in the mean nest temperature from 2012 to 2018, although no differences were found in the period from 2015 to 2018. At Antonio beach, there is no trend since no differences were found in the mean nest temperature except for the years 2013 and 2017, which had lower temperatures than the other seasons. In both beaches mean nest temperature exceeded 30 °C in most of the years. As a result, there was a predominance of nests with incubation periods shorter than 55 days. With these values, a female hatchling production over 90 % is expected in both study sites. Conclusions: In correspondence with the registered temperature and incubation period values, most of the years reflect a hatchling production biased towards females in both beaches. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate biological parameters of Rhipicephalus microplus in the non-parasitic phase in both field and laboratory conditions. It also aimed to assess correlations between duration (in days) of these parameters and climatic variables (humidity, rainfall, and soil temperature) and to estimate the annual number of generations of R. microplus in a tropical region. The non-parasitic phase of R. microplus in field and laboratory conditions was evaluated throughout the course of two years. A pasture was infested with engorged female of R. microplus, and biological parameters, including female pre-oviposition, female oviposition, egg mass incubation, larval pre-hatching phase, larval maturation, and larval longevity, were evaluated concomitantly with the collection of data on climatic conditions. The same parameters were also evaluated in a climatized chamber in the laboratory. The total duration of the non-parasitic phase in the field was longer in the dry season (1st and 4th life-cycle repetitions) than in the rainy season (2nd, 3rd, and 5th repetitions). Tick biological parameters for the non-parasitic phase in the laboratory were similar to those obtained in the field during the rainy season. The evaluated biological parameters were influenced mainly by environmental and ground-level temperatures, which modified egg mass incubation, larval pre-hatching, and larval longevity periods and, consequently, the total duration of the non-parasitic phase of the tick. The annual number of generations for the tick was estimated at five per year, which is alarming because it represents an increase, and so new studies into strategic control are needed. [ABSTRACT FROM AUTHOR]

Reproductive experience can impact how individuals allocate time and energy to reproduction and generate differences in reproductive behavior that leads to experience dependent variation in reproductive success. In order to understand if individual variation in parental behavior is related to environmental temperature and breeding experience, we observed the timing and duration of the first morning off bout in a wild, open cup nesting passerine bird during the incubation and early nestling period. We compared incubation behaviors and nest temperature of inexperienced (second year = first breeding season) and experienced (after second year) female hooded warblers Setophaga citrina. Females left the nest earlier on colder mornings suggesting an energetic constraint due to the long overnight on bout during colder temperatures. During incubation, females increased the duration of the first morning off bout with increasing temperature. Similarly, during the early nestling period, experienced females had shorter off bout duration on colder mornings and increased duration with warmer temperatures. In contrast, inexperienced females increased off bout duration with colder morning temperatures. Experienced females maintained higher nest temperatures and higher minimum nest temperatures compared to inexperienced females. We also found evidence that experienced females nested in microhabitats with higher minimum morning temperature which may buffer older females from colder daily extremes and enable older females to maintain higher nest temperatures. While we found no relationship between incubation and brooding behaviors and fledging success, the proportion of the clutch that hatched was positively related to minimum nest temperature. The ability of experienced females to maintain higher minimum nest temperatures and to adjust brooding behaviors during colder mornings is a potential mechanism that has consequences for nestling condition in a wild population. Our results highlight the need to examine experience-related parental care behaviors in responding to environmental variation. [ABSTRACT FROM AUTHOR]

The process of reproduction is a sensitive period for bird offspring, since they are exposed to environmental conditions for several weeks. Within the long reproductive period, adult birds do not only have to maintain their own body condition, they also have to ensure nutritional needs of their nestlings. In the worst case, if weather conditions are very harsh, breeding is not successful and fails. This suggests that weather conditions might be an important driver of breeding success. Here, we studied the effect of weather conditions (temperature and precipitation) on the survival of 350 nests of great tits Parus major during nestling period in six years (2010-2015). We used traditional generalized linear mixed model (binomial response variable) and a dedicated survival-analysis program (MARK) to analyze the data. The two approaches allowed us to highlight and compare the effect of weather conditions on a fine (nestling survival) and coarse (nest fate) scale. Both methods showed that precipitation explained most of the variation in individual nestling and overall nest survival during the 15-day nestling period. Heavy and persistent rainfall did not only lead to brood reduction, it ultimately also led to losses of the entire brood. Likely causes were the negative effects of precipitation on thermoregulation, food availability and predation risk. However, while reduced food availability most likely might have led to brood reduction through selective individual nestling death, predation might have resulted in total nest failures. [ABSTRACT FROM AUTHOR]