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Cladocerans can produce dormant stages to avoid unfavorable environments, such as predation pressure and population crowding. However, only a few studies evaluated the influences of the biochemical signals of predation risk and population crowding on the termination of dormant stages of cladocerans. This study aimed to investigate the influences of predation risk signals from different predators and crowding signals from high‐density populations on the hatching of cladoceran resting eggs and the anti‐predation defensive traits of hatched offspring. We collected resting eggs of Ceriodaphnia cornuta from the surface of lake sediments and incubated them under different biochemical signals (fish kairomones, Chaoborus kairomones, alarm signals, and crowding signals) in the laboratory. In response to fish kairomones, Chaoborus kairomones, and alarm signals, the hatching time of resting eggs was delayed to a certain extent, and the body length of the offspring hatched from resting eggs increased at their birth and decreased at their first reproduction. This indicated that the offspring hatched from C. cornuta resting eggs possibly can sense predation risk signals but cannot distinguish the type of signals. In addition, the effects of crowding signals on the resting eggs were similar to those of fish kairomones, both of which can increase the body length of hatched offspring at birth, but these influences would not be further enhanced in the simultaneous presence of fish kairomones and crowding signals. This study will contribute to a better understanding of the perception of resting eggs to environmental biochemical signals and the corresponding hatching strategies of cladocerans. [ABSTRACT FROM AUTHOR]

Increased meat and egg production leads to concomitant changes in poultry practices, including the indiscriminate use of formaldehyde to sanitize hatching eggs. Although this sanitizer aids in the increase in poultry production, its toxic potential for man and for avian embryos represents an obstacle to its long-term use. This review assesses whether essential oils fit into the context of hatching egg contamination, reviewing their antimicrobial efficiency, toxicity to poultry embryos and chicks, and their sanitizing effects on poultry production parameters. Studies have indicated that, because they are safer, most of the essential oils studied can be a potential substitute for formaldehyde for minimizing microbial exposure of hatching eggs and embryos. However, complementary studies on the microbiological profile of embryos and chicks hatched from eggs sanitized with essential oils need to be carried out and the economic feasibility of the candidate products should also be considered. [ABSTRACT FROM AUTHOR]

Background: Halyomorpha halys, (brown marmorated stink bug, BMSB), is a high‐concern invasive species causing severe damage to orchards in many countries outside its native Asian range. Management methods other than frequent sprays of broad‐spectrum insecticides are needed to restore integrated pest management (IPM) practices in orchards. Chitin synthesis inhibitors are usually regarded as desirable options in IPM programs because of lower toxicity to beneficial insects and non‐target organisms compared to neurotoxic insecticides. In this study, the activity of three chitin synthesis inhibitors (namely buprofezin, novaluron and triflumuron) was investigated on BMSB egg masses, third instars and adults by means of laboratory bioassays. Results: Novaluron and to a lesser extent triflumuron were detrimental to BMSB nymphs exposed to residues on potted peach plants. Novaluron caused high mortality among early instars that emerged from sprayed egg masses. No significant differences were found between buprofezin and water control on eggs or third instars. When sprayed on BMSB adults, none of the chitin synthesis inhibitors affected survival, fecundity, or egg hatching. Conclusion: Given the activity on nymphs, but the lack of effects on adults, novaluron and triflumuron might be considered for field applications only as a tool in a wider management strategy along with other methods aimed at preventing the invasion of crops by BMSB adults. © 2023 Society of Chemical Industry. [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 current study was aimed at studying the long-term effects of diclofenac on the freshwater shrimp Neocaridina davidi, concerning survival, somatic growth, and reproduction. In this study, both ovigerous females and males of this species were exposed for 63 d to 0 (control), 0.1, or 1 mg/L of diclofenac. At the highest concentration, significant mortality was detected, and the somatic growth of females was significantly decreased. The percentage of females with a second spawn, observable from day 45, significantly increased at 1 mg/L, while the time between spawns was significantly reduced at both concentrations assayed. However, the gonadal analysis made at the end of the assay in the surviving females showed a significantly lower proportion of advanced oocytes in females exposed to 1 mg/L, as compared to control. Concerning hatching, the percentage of ovigerous females that could have successful hatching was reduced at 1 mg/L of diclofenac, especially for the first spawn. For the second spawn, the low number of juveniles hatched from females exposed to 1 mg/L also showed a significantly higher incidence of morphological abnormalities, such as hydropsy and underdeveloped appendages. Taken together, these results showed that even when diclofenac was able to produce earlier spawns, the reproductive output of each spawn was reduced. [ABSTRACT FROM AUTHOR]

Reproduction plays a crucial role in determining the development, fate, and dynamics of bird populations. However, reproductive strategies vary among species and populations. In this study, we investigated the reproductive strategies of the Oriental Magpie Robin (Copsychus saularis) and White-rumped Shama (C. malabarica), which are closely related passerines that reproduce in sympatric areas. We found that although these two species were both cavity nesting, their nest-site selection differed; the Shama preferred nesting close to trees and forests, whereas the Magpie Robin nested close to human residential areas. Furthermore, their egg incubation patterns differed; the Shama increased daily incubation frequency with incubation time, but the Magpie Robin maintained its daily incubation time regardless of changes in incubation frequency. However, the nestling heating patterns of these two species were similar, indicating a critical demand for regulating hatchling body temperature during this crucial stage. The feeding frequencies of male parents were strongly correlated with those of females in both species, suggesting equal contribution and good synchronization between the sexes. Nestling feeding frequency was also correlated with nest cleaning frequency, implying coordination between feeding and defecation by parents and offspring, respectively. This research explored the divergence and convergence of reproductive strategies between these two sympatric species, providing valuable insights into the niche differentiation theory.

This article provides a brief synthesis of the captive breeding of Mikrogeophagus ramirezi, also known as the ram cichlid, in an aquarium. The article discusses the selection of a healthy pair, creating an adequate environment with the right water parameters, feeding and nutrition, stimulating reproduction, courtship and egg deposition, incubating the eggs, caring for the fry, separating the juveniles, and continued monitoring and care. The article emphasizes the importance of maintaining stable water parameters, providing a suitable diet, and regularly cleaning the aquarium. Overall, reproducing M. ramirezi in an aquarium can be a beautiful and educational experience. [Extracted from the article]

The article describes the previously undocumented behavior of post-hatch egg laying by American Black Vultures (Coragyps atratus), citing two instances in western Kentucky, U.S., during nest monitoring. Topics include the rarity of such behavior, potential explanations, and the need for further research to understand the factors influencing this phenomenon in Black Vultures.

By preheating the eggs before incubation, all embryos are set to the same developmental stage. In this manner, the hatching window can be shortened and hatchability can increase. Before incubation, a total of 491 partridge and 460 guinea fowl eggs were preheated at 28°C and 60% relative humidity for 0, 4, 6, and 8 hours. Preheating significantly affected hatchability in both partridge and guinea fowl eggs. In partridge eggs, the hatchability of fertile eggs was 73.31% in the 0-hour preheated group and 92.94% in the 8-hour preheated group. The hatching rates of guinea fowl eggs were 69.60, 80.07, 84.38 and 78.23% in the 0, 4, 6 and 8 hours preheated groups, respectively. Partridge keets hatched from preheated eggs had significantly better quality, while guinea fowl keets did not differ in quality. [ABSTRACT FROM AUTHOR]

The eggs laid by the orb web spider Trichonephila clavata must overwinter in bitterly freezing and dry conditions before hatching, but there does not seem to be any protection like a compact silk case covering the entire eggmass. Instead, the surface of the eggmass is completely coated with a milky coating called chorionic microspheres (CM). Therefore, we investigated the fine structural characteristics of CM to demonstrate their ecological importance. Although the diameter of CM in outer eggmass exhibits a significant variation, the chorionic surface is coated with a single layer of CM, characterized by a consistent diameter of approximately 2.3 µm. The surface structure of aggregated CM shows short papillary projections demonstrating segmental adhesion of mucous components. CM is insoluble in water but partially soluble in anhydrous ethanol, and its spherical structure is completely decomposed by hexafluoroisopropanol (HFIP), a strong organic solvent. Since our fine structural observations clearly show that CM is not derived from vitellogenic or choriogenetic processes, the CM adhesive coatings during ovipositional process appears to be equivalent to cocoon silk for various protective functions in silken eggcase. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of different egg weights on egg external quality characteristics and hatching performance in Pekin ducks. A total of 800 eggs were divided into three weight categories: "light" (Lo; <76 g), "medium" (Me; 76-82 g), and "heavy" (Hi; >82 g). Parameters indicating egg external quality characteristics were calculated. Eggs were incubated and on the 25th day, transferred to the incubator for hatching. The mean egg weight for light, medium, and heavy categories were 70.25 g, 78.47 g, and 85.17 g, respectively (P<0.001). As egg weight increased, there was a significant decrease in shell thickness (P<0.001). The effect of different egg sizes on fertility was insignificant. The hatchability of fertile eggs was higher in the light and medium categories compared to the heavy category (P<0.05). Egg weight had a significant effect on early embryonic mortality rate (P<0.05) and chick hatch weight (P<0.001). In conclusion, different egg weights have varying effects on egg external quality parameters in Pekin ducks. Although heavy eggs produce chicks with higher weights, lighter or medium-weight eggs may be more advisable for incubation due to their better hatchability. [ABSTRACT FROM AUTHOR]

The study of a nest of Long-legged Buzzard Buteo rufinus was carried out using a trail camera and is one piece of a completely unknown jigsaw puzzle of diet and nesting behaviour in Romania. With a hatching success of 75%, we identified 3 hatched chicks from the 4 eggs. During the 10 days of monitoring, 34 preys brought to the nest were identified, with a peak of activity between 11:00--17:00 and a preference for the European Ground Squirrel Spermophilus citellus (61.76%). This was followed by the Domestic Pigeon Columba livia f. domestica and the Common Wood Pigeon C. palumbus (5.88%), and amphibians were represented by the European Green Toad Bufotes viridis (2.94%). There were 10 unidentified prey species (29.41%). We identified the presence of plastic and textile fibres in the nest and the risk of chick suffocation. We also improved our understanding of interspecific interactions and our observations highlighted the mutualism between the three species in the nest: Spanish Sparrow, House Sparrow and LLB. The removal of solitary trees from the agricultural landscape is a major threat in south-western Romania, affecting the breeding population of the LLB, which, as in our case, nests on this type of support. [ABSTRACT FROM AUTHOR]

The article is about the Blandings night tree snake (Toxicodryas blandingii), a tree-dwelling snake found in tropical Africa. Four species are identified in the genus Toxicodryas. The Blandings night tree snake prefers moist forests, is nocturnal, and can grow up to 250 cm long. In terrariums, they are usually calm and docile, but caution is advised as they have venomous teeth. Keeping them requires a spacious terrarium with plenty of climbing branches and plants for visual barriers. The snake can reproduce year-round, with a clutch of 5 to 7 eggs per year. The article also describes the rearing of Blandings night tree snakes, in which the female has attached two eggs to the outside of the hatching box. The first baby hatched after 115 days. The juveniles are raised individually in glass terrariums and fed with live mice. It is noted that the venom of Toxicodryas blandingii contains a neurotoxin that appears to be stronger than that of Boiga species. The text also includes a list of captive-bred snakes of various species in 2022, including venomous species such as Vipera ammodytes meridionalis and Trimeresurus insularis. [Extracted from the article]

Effects of egg storage length and orientation on hatching traits and spread of hatch were determined in Transylvanian naked neck chickens. Eggs (n = 640) stored in a cold room (16 ± 1.5°C, 75 ± 1.5% RH) in batches of 160 eggs each, for 1, 3, 5 or 7 days were used. Half of each batch was stored with a broad end up (BEU) and the other in a narrow end up (NEU). Eggs were incubated in a two‐stage incubator (37.5°C, 64% RH). Storage length caused a significant increase in egg weight loss (EWL; p < 0.001). Egg fertility (FERT) was significantly lower in 7 days than in 1, 3 and 5 days stored eggs (p < 0001). Dead in shell (DIS) was lower (p < 0.001) in 1‐day storage than in other lengths (p < 0.001). Hatchability of total (HSE) and fertile eggs (HFE) decreased (p > 0.001) gradually from 1 to 7 days, though 3 and 5 days were found to be similar. Hatching commenced earlier (p = 0.055) in 5 days than 1‐day storage. Incubation time at 100% hatch, hatch window and spread of hatch were not (p > 0.05) affected by storage length. At the end of the hatch, longer storage than 1 day caused 45, 45 and 15 min/day delay in hatching for 3, 5 and 7 days storage respectively. The chicks from 3 days storage (17.3 cm) were longer (p = 0.05) than those from 5 (17.1 cm) and 7 days groups (17.1 cm). Higher DIG and DIS but lower HSE and HFE (p < 0.05) were recorded in BEU than in NEU orientation. Earlier commencement of hatch (CH) was recorded in BEU than in NEU eggs. There were significant (p < 0.05) interactions between storage length and orientation in FERT, DIG, HSE, HFE, CH and hatch windows. To achieve HFE up to 70%, eggs could be stored for up to 7 days in NUE orientation but should not exceed 3 days in BEU orientation. [ABSTRACT FROM AUTHOR]

Bird parents may choose among various breeding strategies. From an evolutionary point of view the outcome of their choice is believed to provide the highest reproductive success in a given environment. However, some of the mechanisms underlying parental reproductive decisions are still poorly understood, for example the phenomenon of hatching asynchrony. Resultant age and size hierarchy among nest mates often lead to competitive disadvantages, starvation and death of last-hatched siblings. Although synchronised broods generally result in higher fledging success, altricial bird species typically hatch asynchronously. Various hypotheses were proposed and tested to explain this strategy. A quarter of a century has passed since the last review of research on hatching asynchrony. In the meantime the number of studies investigating the issue has considerably grown, same as the array of hypotheses. Our aim is to present a comprehensive synthesis of the research on 20 hypotheses presented until recently as well as to indicate the blind spots in the reviewed area—9 out of 20 formulated hypotheses still lack any experimental approach that would confirm or reject the assumptions. [ABSTRACT FROM AUTHOR]

Studies on normal concentration of blood constituents of free-living birds are not very common. An adequate knowledge of blood chemistry is greatly recommended for those projects involving research and management of populations as far as they can be valuable for the assessment of the nutritional levels and health status of species. No previous published reports on these parameters from this species are available. The aim of this study was to obtain representative reference measures for hematologic and biochemical values in free-living clinically healthy wild White-tailed Sea Eagle nestlings (Haliaeetus albicilla). In addition, we investigated potential relationships between blood parameters, sex, age and hatching dates. Blood samples were obtained as part of routine monitoring and management when wild chicks were removed from their nest as part of a reintroduction program prerelease health check. A total of 83 nestlings, 43 males and 40 females, between 41 and 66 days of age (mean = 54.22, SD = 5.7), were sampled. Significant differences between sexes were found. Among hematological parameters, MCH, lymphocytes P and thrombocytes showed significant differences between males and females. In biochemical parameters, significant differences were found only in calcium, CK and LDH between sexes. No effect was found of age of the nestling when the sample was taken in any of the analyzed hematological parameters. No other significant relationships were found between biochemical parameters and other considered explanatory variables. Hatching date showed no relationship with blood parameters excepting urea. Urea was the only variable showing a strong relationship with hatching date, with those nestlings hatching later in the season showing higher urea concentration. [ABSTRACT FROM AUTHOR]

Simple Summary: In alternative poultry production systems, a key aspect for the viability of the hatching egg is its storage before incubation, its management being less standardized than in intensive poultry farming. The objective of this work is to investigate the effect of the long-term storage of game farmed quail eggs by testing storage periods of up to 35 days at 15.8 °C and 80% relative humidity. It was found that the hatchability was maintained in eggs stored up to 28 days and decreased when storage was extended to 35 days. The eggs progressively lost more weight as the storage time increased, producing chicks with lower weight from eggs stored for more than 14 days and with lower relative chick weight in those stored for 35 days. The length of the incubation period increased progressively with storage time, while hatching synchrony decreased. In conclusion, if necessary for management reasons, game quail hatching eggs can be stored without relevant loss of viability for up to 28 days before incubation. The practical implications are that this ensures a long market life when hatching eggs are sold and allows small farms to collect enough eggs over an extended period to fully set an incubator. The long-term storage of eggs before incubation is a common practice in some alternative poultry systems but needs to be performed under conditions that preserve egg viability. The effects of the long-term storage of game farmed quail (Coturnix coturnix) eggs on weight loss during the storage and incubation periods, chick weight at hatch, hatchability, and incubation length were investigated. The eggs were arranged in six treatments submitted to 0-, 7-, 14-, 21-, 28-, and 35-day storage periods at 15.8 °C and 80% relative humidity. The storage length reduced the hatchability of eggs (p < 0.05) when the storage was extended to 35 days, decreasing by more than half compared to eggs stored up to 28 days. Egg weight loss during storage progressively increased with the storage length (p < 0.05). Chick weight at hatching was reduced in eggs stored for more than 14 days (p < 0.05), and relative chick weight decreased significantly in eggs stored for 35 days (p < 0.05). Incubation length progressively increased with the storage length (p < 0.05), achieving less hatching synchrony in eggs stored for a longer time (p < 0.05). In conclusion, game quail eggs store well with little deterioration up to 28 days at 15.8 °C and 80% relative humidity, allowing for extended storage when shipping long-shelf-life eggs or assembling batches large enough to fully set an incubator in farms with small breeding flocks. [ABSTRACT FROM AUTHOR]

Simple Summary: The Spectacled Fulvetta (Fulvetta ruficapilla sordidior) is an endemic bird species of the mountains in southwest China. The breeding biology of this species is largely unknown. In order to describe the breeding biology of this species, this study was conducted for two years on Humashan Mountain, a hill mainly covered with secondary forest located at the eastern marginal of Kunming, the capital city of Yunnan Province in Southwest China. A total of 16 nests were found, mainly located in dense shrubs. The breeding season is from March to June, with its peak period from April to May. The clutch size is 2–3, most of which are 3 eggs. The incubation period is 13–14 days, and the nesting period is 12–14 days. Both parents participated in the breeding process. We found a total of 16 nests, of which only 11 were active; 5 were successfully fledged with at least one (45.45%). This study is the first report on the breeding biology of the Spectacled Fulvetta, which has scientific value for the understanding of this species and other relative species in the Fulvetta genus. The Spectacled Fulvetta (Fulvetta ruficapilla sordidior) is an endemic bird species to the southwest mountains of China, distributing from 1250 to 2500 m in the widespread broadleaved evergreen forest and occasionally in secondary scrubs. The present study describes its breeding biology for the first time. Fieldwork was conducted in the springs of 2017 and 2018 on Humashan Mountain, a hill mainly covered by secondary forest located at the eastern marginal of Kunming, the capital of Yunnan Province in Southwest China. This bird was found to initiate egg-laying mainly in March, and most nestlings fledged in late April and May. There were 16 nests found in total, which were located mainly in the dense shrubs at a height of 0.99 ± 0.40 m (n = 15). Of the 11 active nests, clutch size averaged 2.73 ± 0.45 (n = 11). Focal observations were made on nests; the incubation lasted for 13.67 ± 0.47 days (n = 3) with a notably high nest attendance, i.e., eggs were incubated 84.23% of the observation time. Nestlings fledged at 13.00 ± 0.71 days (n = 4), and parents feeding frequency increased as the nestlings grew. Overall, the cumulative hatching and fledgling rates were 71.43% and 35.71%, resulting in a nesting success rate of 45.45%. [ABSTRACT FROM AUTHOR]

Guinea fowl meat and eggs are highly prized by consumers in the Sudan-Sahelian belt countries such as Burkina Faso and Niger. However, compared to chicken, guinea fowl stocks in these countries are low. One of the reasons for the low stock holdings is that guinea fowl in captivity are poor at being broody hens. They do not sit on their eggs for the hatching of their keets. This problem has been addressed using synchronized surrogate chicken hens for brooding. Many chicken hens are provided with dummy eggs until they begin to brood, at which time the dummy eggs are switched to fertile guinea fowl eggs. The challenge with this solution is storing the guinea fowl eggs at room or ambient temperatures until the surrogate brooders are ready. The high room temperatures during storage initiates preembryo development that results in hatching unhealthy keets. Refrigerated storage is not an option, as most smallholder farmers in rural settings do not have access to electricity. The purpose of this study was to address the storage problem by introducing wind-driven evaporative cooling (YaiKuula); "Yai" is a Swahili word for "egg." YaiKuula lowers the storage temperature ~15 ℃ below ambient temperature during the day. Viable guinea fowl eggs were stored using YaiKuula for 0-3, 4-7, and 8-14 days. Ambient temperature and refrigerated (8 ℃) storage were done in parallel as negative and positive controls, respectively. Twenty-four surrogate brooders with six eggs each were used to hatch the stored eggs. Early and late embryo mortality, in addition to healthy hatching were monitored. The Student's ttest was used to compare results. The highest rate (p<0.05) of early embryonic mortality (65%) was obtained with refrigerated storage for 8-14 days versus 37 and 12%, respectively, for ambient and YaiKuula storage for the same length of time. The hatching rates of eggs from 0-3 days of storage showed no significant difference between the three storage methods. However, YaiKuula storage yielded significantly (p<0.05) higher hatching rates of 80% versus 37 and 22% from ambient and refrigeration storage at 8-14 days, respectively, and 84% versus 65 and 61% for ambient and refrigeration storage at 4-7 days, respectively. YaiKuula has the potential to increase the number of guinea fowl among smallholder poultry farmers for increased incomes/resilience and better nutrition. [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]

Copyright of Journal of Kirkuk University for Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In industrial quail breeding all hatching eggs are subjected to preliminary selection according to external features and egg weight. This means that the issues of evaluating hatching eggs, increasing hatchability, and the viability of young animals during artificial incubation do not lose their relevance. Comparative assessment was carried out on the quality of incubation eggs of Estonian and Manchurian Golden quail breeds with different mass-to-volume ratios, as well as the results of incubation and the values of electromagnetic impulses during the incubation of quail eggs. The material for the study was the eggs of the Estonian and Manchurian Golden (MG) breeds of quials. Eggs were selected with a shelf life of no more than 7 days. At the first phase, 100 eggs of each breed were opened and morphologically analyzed. At the second, three incubations were carried out. For each incubation, 150 eggs of the Estonian and Manchurian Golden breeds were selected, of those, 50 eggs were opened and a morphological analysis of the eggs of each breed was made. The incubation of quail eggs at the 2nd phase was carried out in IPH-10 incubators. At the 3rd phase, eggs were incubated individually in an R-COM DX-8800XP incubator. During incubation, the development of embryos was monitored by candling eggs on days 6, 11, and 16 of incubation. In the Manchurian Golden breed, 7.5 times fewer eggs fell into the first variation class, and 2.3 times more eggs into the third variation class compared to the Estonian breed (p < 0.05). The large diameter of the egg increased on average by 4.3%, while the small one decreased by 3.2%. Egg shape index increased by 3.3% in Manchurian eggs, while by 2.9% in Estonian eggs (p < 0.05). The value of the "Haugh unit" index decreased by 4.2% in the eggs of the Manchurian Golden breed, while by 5.9% in the eggs of the Estonian breed (p < 0.05). The ratio of mass and volume significantly affected the results of incubation of eggs. In the second and third classes, an average of 6.1 and 2.7% more quials hatched than in the first class. In terms of hatchability of eggs, these differences were more significant and amounted to 15.8 and 14.0%, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Computational Systems & ICTs is the property of ECORFAN-Mexico S.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The king penguin (Aptenodytes patagonicus) is a subantarctic species, but breeders were recently reported in Antarctica. Stranger Point (South Shetland Islands) represents the southernmost breeding site recorded so far. Here, we report the observations of king penguins molting and attempting to breed at Stranger Point during 11 consecutive years, and the first record of a molting individual at Esperanza/Hope Bay (tip of the Antarctic Peninsula). From 2011/2012, breeding attempts occurred every year at Stranger Point, except in 2021/2022. Only during 2014/2015 and 2016/2017, a chick hatched and survived until 5 months and 1 month old, respectively. In the remaining seasons, the egg was abandoned before hatching. In mid-February 2018, a dead adult king penguin was found, and then only a female adult was observed there. Strikingly, during 2017/2018 and 2018/2019, a second egg was laid some days after the first egg was abandoned. Unfortunately, the pair was not able to establish itself at Stranger Point, and no further sightings of molting king penguins were recorded at Esperanza/Hope Bay since the 2018/2019 season. Notwithstanding this, our observations highlight the importance of reporting all records of king penguins in Antarctica, thus providing fundamental information to assess future climate-driven shifts in the bio-geographic range of this species and the status of the population. [ABSTRACT FROM AUTHOR]

Simple Summary: Life history and its related theories are one of the most important topics in behavioral ecology, population ecology, and evolutionary biology. The reproductive ecology of birds is the cornerstone of avian life-history theory, and the success or failure of reproduction directly affects the survival and development of the population. This study investigated the reproductive ecology of chestnut-vented nuthatch (Sitta nagaensis) using artificial nest boxes to attract these secondary cavity-nesting birds. The study focused on a series of breeding activities and is the first breeding record of S. nagaensis in southwestern China, providing a basis for further reproductive ecology studies of this species. The breeding ecology of birds is the cornerstone of bird life-history theory, and breeding success directly affects the survival and development of populations. We studied the breeding ecology of a secondary cavity-nesting bird, the chestnut-vented nuthatch Sitta nagaensis, in southwestern China from March to June in 2020, 2021, and 2022. In total, 16 nests in nest boxes and 19 nests in natural cavities were studied. The nesting habitat was mainly Pinus yunnanensis forest (68.4%), and the nest trees were mainly P. yunnanensis and pear Pyrus spp. Cavities made by woodpeckers and knot holes were used as nest sites, and the nuthatches plastered the hole entrance with mud. The nesting material was mainly pine bark. The clutch size was 3.47 ± 0.56 (range 2–4, n = 30), with an incubation period of 16.06 ± 0.91 days (range 15–19 days, n = 18). The nestling period was 20.88 ± 1.90 days (range 18–23 days, n = 23), and both parents fed the nestlings. [ABSTRACT FROM AUTHOR]

The males of the giant water bug, Kirkaldya deyrolli, care for egg masses on the emergent vegetation above the water surface in aquatic environments. A previous study reported that attending males supply the eggs with water and guard them against mature females (infanticide) until hatching. That study additionally concluded that males staying on the egg mass for longer than necessary may be a counterstrategy against females considering infanticide. In the present study, laboratory experiments were performed to evaluate the effect of conspecific females on paternal care during the egg-attending period using "with-" and "without-female" treatments. The hatching rates of eggs guarded by males with or without the presence of females were not significantly different. However, the proportion of males on the egg mass was significantly higher when the females were present than when not. We conclude that male behavior may be a counterstrategy against infanticidal females, in which males avoid and reduce the risk of detection by climbing out of the water when females are present. [ABSTRACT FROM AUTHOR]

Chersina angulata females ovulate sequentially and oviposit multiple, mostly single egg clutches from early autumn (March) throughout winter and spring until early summer (December). No matter when eggs are laid, they usually hatch in autumn (March/April). Evidence based on circumstantial observations also demonstrates that wild and captive females occasionally retain the last clutch of the season until completion of embryonic development in autumn, conforming to the accepted definition of viviparity in reptiles. However, developmental progress throughout the year and embryonic stages of freshly deposited last clutches has not yet been reported. We candled all eggs laid from April to December in a captive colony of C. angulata in an outdoor enclosure in Cape Town, South Africa, to estimate developmental progress and embryonic stages. In all eggs laid during autumn, winter, and early spring (March to mid-October), vitelline blood vessels, indicating development had progressed to somite formation, only started to become visible at approximately the same time in late November. Until mid-spring, embryonic development of those eggs had been arrested prior to somite formation; the embryos underwent diapause until, presumably, increasing temperatures reinitiated development. Development then progressed throughout summer until the hatching stage was reached in early autumn. However, eggs laid in late spring (mid-October to November) skipped diapause, and embryonic development progressed without interruption, demonstrating that, depending on the season of oviposition, diapause in C. angulata is facultative. Candling of an egg laid in late December showed that, prior to oviposition, embryonic development inside the female had already advanced to an embryonic stage with well-developed vitelline circulation corresponding to Yntema stage 12. Contrary to the generally accepted wisdom that intrauterine embryonic development in the order Testudines is always arrested at the gastrula stage, embryonic development inside the female had already reached the stage of somite formation. This phenotypic plasticity in the expression or abolishment of preovipositional developmental arrest represents a transitional stage in the evolution towards viviparity. [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]

Recently, scientists searched for safe alternatives to synthetic insecticides to manage the cotton leafworm Spodoptera littoralis. Of these alternatives are microbial-based insecticides. These compounds are known for their unique larvicidal activity, especially against Lepidopterous insects. In this regard, the present investigation was carried out to evaluate the latent and histopathological influence of Bacillus thuringiensis var. kurstaki (Btk) and Spodoptera littoralis nuclear polyhedrosis virus (SpliNPV) either individually or in a mixture against the adult female of S. littoralis. The LC50 values of the tested entomopathogens were determined. The impact of median lethal concentrations of tested entomopathogens on adult longevity, fecundity, and fertility was assayed after treating 2nd instar larvae. In addition, the histological changes in female ovaries due to treatment were investigated. Results showed that the low LC50 value showed that Btk+SpliNPV was the most hazardous against the 2nd instar larvae, followed by SpliNPV and Btk. All tested entomopathogens did not cause high immediate larval mortality; however, larval mortality increased throughout the larval stage until pupation. There was also a significant reduction in fecundity and fertility of emerged females resulting from 2nd instar larvae treatment. In addition, the treatment caused severe alterations in the histological structure of ovarioles. These findings support entomopathogens as a non-toxic alternative to conventional pesticides for controlling the cotton leafworm. Because of this, the population density of succeeding generations may decline since these organisms kill the treated larvae and have delayed effects that appear to reduce the eggs deposited and hatching. The results explain the reduced reproductive potential since these entomopathogens influence the female reproductive system when applied alone or as a mixture. [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]

Simple Summary: The study evaluates the hybridizations in two African catfish, i.e., C. gariepinus and C. macromystax, using artificial reproduction. Reproductive and growth performance were evaluated. The results indicated that both species possess a similar gonadosomatic index. The parent C. gariepinus possesses higher male reproductive quality than C. macromystax. Fecundity was higher in the female parent of C. macromystax and lower in the C. gariepinus species. The highest fertilization rates and hatching rates were achieved in the hybrid cross of C. macromystax × C. gariepinus, which also recorded the lowest deformed larvae. Survival rates at the larval stage were more than 80% with the highest record of survival in the hybrid C. macromystax × C. gariepinus. However, survival rates in the fry stage were lower than 70%. The hybrid cross (C. macromystax × C. gariepinus) showed the best growth performance, which was similar to the parental cross (C. gariepinus × C. gariepinus). The study revealed the potentials of the hybrid C. macromystax × C. gariepinus, and hybridizations of C. macromystax × C. gariepinus (Cm × Cg) are indeed possible and proved to have better growth and survival rate under semi-arid conditions, which would contribute significantly to the improvement of C. macromystax production in captivity. The study evaluates the hybridizations between two African catfish, C. gariepinus and C. macromystax, using artificial reproduction. Fecundity and gonadosomatic index were assessed, and growth performance at different developmental stages was evaluated. The results indicated that both species possess a similar gonadosomatic index. The parent C. gariepinus possesses significantly (p < 0.05) higher male reproductive quality than C. macromystax. Fecundity was significantly higher (p < 0.05) in the female parent of C. macromystax and lower in C. gariepinus. The highest fertilization rates and hatching rates were achieved in the hybrid cross of ♀C. macromystax × ♂C. gariepinus (♀Cm × ♂Cg) which also recorded the lowest deformed larva rate. Survival rates at the larval stage were more than 80%, with the highest record of survival in the hybrid ♀Cm × ♂Cg. However, survival rates in the fry stage were lower than 70%. The hybrid cross (C. macromystax × C. gariepinus) outperformed the parental cross of C. macromystax but was not significantly similar to the parental cross of C. gariepinus. The study revealed the potential of the hybrid ♀C. macromystax × ♂C. gariepinus, and hybridizations of ♀C. macromystax × ♂C. gariepinus (♀Cm × ♂Cg) are indeed possible and proved to have a better growth and survival rate under semi-arid conditions, which would contribute significantly to the improvement of C. macromystax production in captivity. [ABSTRACT FROM AUTHOR]

Mothers who produce multiple offspring within one reproductive attempt often allocate resources differentially; some maternally derived substances are preferentially allocated to last‐produced offspring and others to first‐produced offspring. The combined effect of these different allocation regimes on the overall fitness of offspring produced early or late in the sequence is not well understood, partly because production order is often coupled with birth order, making it difficult‐to‐separate effects of pre‐natal maternal allocation from those of post‐natal social environments. In addition, very little is known about the influence of laying order on fitness in later life. In this study, we used a semi‐natural captive colony of black‐headed gulls to test whether an offspring's position in the laying order affected its early‐life survival and later‐life reproductive success, independent of its hatching order. Later‐laid eggs were less likely to hatch, but among those that did, survival to adulthood was greater than that of first‐laid eggs. In adulthood, the laying order of females did not affect their likelihood of breeding in the colony, but male offspring hatched from last‐laid eggs were significantly less likely to gain a breeding position than earlier‐laid males. In contrast, later‐laid female parents hatched lower proportions of their clutches than first‐laid females, but hatching success was unrelated to the laying order of male parents. Our results indicate that gull mothers induce complex and sex‐specific effects on both the early survival of their offspring and on long‐term reproductive success through laying order effects among eggs of the same breeding attempt. [ABSTRACT FROM AUTHOR]

Determining the saline niche of the congeneric and co‐existing species that inhabit supralittoral rockpools subjected to extremely fluctuating saline conditions is a crucial concern to understand their spatial distributions and occurrence, and to predict their ability to face increasing environmental instability due to climate change.Therefore, we compared the realised and fundamental saline niches of Ochthebius quadricollis and Ochthebius lejolisii (Coleoptera: Hydraenidae) on the Mediterranean coast of the Iberian Peninsula.A realised niche was determined using field data on the abundance of the adults and larvae of both species.A fundamental niche was addressed with laboratory experiments by measuring the survival of the adults and larvae and the egg‐hatching success exposed to different salinity treatments (35, 60, 90, 110, 140 and 170 g L−1).Our study found a discordant pattern between realised and fundamental niches. Both species are euryhalines and support extreme salinity fluctuations from 1.80 to almost 140 g L−1, and O. quadricollis larvae in the field withstand up to 180 g L−1.However, physiological tolerance was greater in O. lejolisii than in O. quadricollis, and O. lejolissi adults survived in the laboratory at 170 g L−1 for more than 3 days with 30% egg‐hatching success, whereas O. quadricollis showed a maximum survival time of 2 days and no egg‐hatching success at that salinity.The larvae and eggs of both species were more tolerant than adults.The two studied species exhibited high physiological capacity to tolerate extremely fluctuating salinity, which will be exacerbated by climate change. [ABSTRACT FROM AUTHOR]

The severe shortfall in testing supplies during the initial COVID-19 outbreak and ensuing struggle to manage the pandemic have affirmed the critical importance of optimal supplyconstrained resource allocation strategies for controlling novel disease epidemics. To address the challenge of constrained resource optimization for managing diseases with complications like pre- and asymptomatic transmission, we develop an integro partial differential equation compartmental disease model which incorporates realistic latent, incubation, and infectious period distributions along with limited testing supplies for identifying and quarantining infected individuals. Our model overcomes the limitations of typical ordinary differential equation compartmental models by decoupling symptom status from model compartments to allow a more realistic representation of symptom onset and presymptomatic transmission. To analyze the influence of these realistic features on disease controllability, we find optimal strategies for reducing total infection sizes that allocate limited testing resources between 'clinical' testing, which targets symptomatic individuals, and 'non-clinical' testing, which targets non-symptomatic individuals. We apply our model not only to the original, delta, and omicron COVID-19 variants, but also to generically parameterized disease systems with varying mismatches between latent and incubation period distributions, which permit varying degrees of presymptomatic transmission or symptom onset before infectiousness. We find that factors that decrease controllability generally call for reduced levels of non-clinical testing in optimal strategies, while the relationship between incubation-latent mismatch, controllability, and optimal strategies is complicated. In particular, though greater degrees of presymptomatic transmission reduce disease controllability, they may increase or decrease the role of nonclinical testing in optimal strategies depending on other disease factors like transmissibility and latent period length. Importantly, our model allows a spectrum of diseases to be compared within a consistent framework such that lessons learned from COVID-19 can be transferred to resource constrained scenarios in future emerging epidemics and analyzed for optimality. [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]

Background: In Pakistan, the naked neck chickens are characterized on the base of plumage colors such as black, white black, light brown and dark brown. There is scanty of information on hatching traits in different phenotypes of naked neck chicken. The current study aimed to investigate and compare the hatching traits in four phenotypes of naked neck chicken (black, white black, light brown and dark brown). Methods: In total, 300 females (20 weeks old) comprising four plumage colors (black, white black, light brown and dark brown), 75 from each, were randomly assigned to 20 replicates (15/replicate) under a completely randomized design (CRD). Number of settable eggs, fertility, hatch of fertile, hatchability, embryonic mortality and chick quality parameters were evaluated. Result: The results showed higher settable eggs, fertility and hatchability in black, dark brown and light brown phenotypes than that of the white black whereas better hatch of fertile and reduced embryonic mortality were recorded in black and dark brown phenotypes as compared to white black. Better chick quality was observed in dark brown phenotype followed by light brown, black and then white black. Phenotypes other than white black had better hatching performance, hence could be used to revive backyard poultry farming. [ABSTRACT FROM AUTHOR]

One of the major problems impeding the sustainable development of goose production is low egg hatchability. Thus, it is imperative to develop more efficient ways to improve the hatching qualities of goose eggs. The present study aimed to investigate the effects of changes in the temperature regime of incubation on the availability of vitamins A (retinol) and E (α-tocopherol), as well as important elements of antioxidant protection in embryos and goslings. The initial heating of eggs at temperatures of 39 and 39.5 °C during the first 24 or 36 h was used as the main factor influencing goose embryo development. The dynamics in the content of antioxidant retinol and α-tocopherol were analyzed in the liver of embryos and goslings (up to 9 days of age) using the standard regime of incubation (at 38 °C) and the prior heating of eggs (at 39 °C and 39.5 °C) in the first 24 and 36 h of incubation. The obtained results provided new information about the effect of the initial heating of eggs on the function of antioxidants in the gosling's body. It was confirmed that the age-related changes of retinol and α-tocopherol levels in goslings are similar to those found in chicks, ducklings, and turkey-poults. In addition, the effect of an egg's weight on hatchability was established, with the hatchability of eggs in the medium weight class being higher than that of smaller and larger eggs. The efficiency of the redistribution of retinol from the yolk to the liver in day-old goslings was higher by 6% when exposing eggs to a temperature of 39.5 °C for 36 h. The initial heating regime at 39.5 °C led to an increased hatch of goslings, and to the evenness of their hatch from eggs of different weights, approaching the hatch values of the medium class. Overall, the α-tocopherol concentration in the liver of embryos and goslings, using the starting heating of eggs, was higher than that with the standard temperature mode of incubation. At the same time, the hatch rate of goslings increased by 9–13%, and the hatchability of eggs by 10–16%. For use in the practice of hatcheries and breeding poultry farms, it is recommended that goose eggs are heated for 36 h at 39.5 °C. [ABSTRACT FROM AUTHOR]

Snowy Plovers (Charadrius nivosus) are a species of conservation concern in Alabama, U.S.A., where the breeding population is small and restricted to just a few sites. Despite their listing, little research has been conducted on this species in the state. Snowy Plover nests (n = 119) were monitored at Bon Secour National Wildlife Refuge during 2015–2020. Just over half (53%) of all nests successfully hatched one or more chicks. Daily survival rates of Snowy Plover nests were estimated at the refuge using several temporal and environmental covariates. Constant daily survival rate was estimated at 0.97 (SE = 0.004, 95% CI = 0.97–0.98) and the probability of a nest surviving the 32-day incubation period was 0.42 (95% CI = 0.33–0.52). The top model in the nest survival analysis included year and site. This study is important in furthering our understanding of Snowy Plover populations in Alabama and can be used as a baseline for future analyses of nest survival. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Egg size in birds is a factor that affects their reproductive success, especially in the size and survival rates of the chicks. Until they learn to find food within a few days after hatching, precocial-type chicks need to use their own biological reserves to supply the energy they expend in walking, running, hiding from predators, etc. The spur-winged lapwing Vanellus spinosus (L., 1758) is a common lapwing species having precocial-type offspring. The species is seen as a summer visitor in Türkiye and Boğazkent is one of its important breeding areas in the country. In the present study, the characteristics of the eggs laid in three habitats (agricultural lands, barren lands and meadows) within this area were compared. To this purpose, the eggs were weighed and their width and length were measured. In addition, the volume and sphericity index of the eggs were calculated. We found significant differences in egg measurements between the habitats with eggs laid in meadows being larger, heavier and with greater egg volume than in the other two habitats. However, the hatching rates in the meadows were the lowest (43.8 %) in comparison with the agricultural lands (67.7 %) and barren lands (73.3 %), possible due to potentially higher predation pressure in meadows. [ABSTRACT FROM AUTHOR]

Copyright of Acta Zoologica Lilloana is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Philaenus spumarius L. the main vector of Xylella fastidiosa (Wells) in Europe, is a univoltine species that overwinters in the egg stage, and its nymphs emerge in late winter or spring. Predicting the time of egg hatching is essential for determining the precise times for deploying control strategies against insect pests. Here, we monitored P. spumarius eggs from oviposition to egg hatching together with the daily temperatures and relative humidities at four field locations that were located at different altitudes in central Spain. The collected data were used to build a growing degree day (GDD) model to forecast egg hatching in the Iberian Peninsula. Furthermore, the model was validated with field observations that were conducted in Spain. The model was then used as a decision-support tool to calculate the optimum timing for applying control actions against P. spumarius. Our results suggest that controlling nymphs at two different dates would target the highest percentages of nymphal populations present in the field. Our model represents a first step for predicting the emergence of nymphs and adopting timely control actions against P. spumarius. These actions could limit disease spread in areas where X. fastidiosa is present. [ABSTRACT FROM AUTHOR]

The microbiota is suggested to be a fundamental contributor to host reproduction and survival, but associations between microbiota and fitness are rare, especially for wild animals. Here, we tested the association between microbiota and two proxies of breeding performance in multiple body sites of the black‐legged kittiwake, a seabird species. First we found that, in females, nonbreeders (i.e., birds that did not lay eggs) hosted different microbiota composition to that of breeders in neck and flank feathers, in the choanae, in the outer‐bill and in the cloacae, but not in preen feathers and tracheae. These differences in microbiota might reflect variations in age or individual quality between breeders and nonbreeders. Second, we found that better female breeders (i.e., with higher body condition, earlier laying date, heavier eggs, larger clutch, and higher hatching success) had lower abundance of several Corynebacteriaceae in cloaca than poorer female breeders, suggesting that these bacteria might be pathogenic. Third, in females, better breeders had different microbiota composition and lower microbiota diversity in feathers, especially in preen feathers. They had also reduced dispersion in microbiota composition across body sites. These results might suggest that good breeding females are able to control their feather microbiota—potentially through preen secretions—more tightly than poor breeding females. We did not find strong evidence for an association between reproductive outcome and microbiota in males. Our results are consistent with the hypothesis that natural variation in the microbiota is associated with differences in host fitness in wild animals, but the causal relationships remain to be investigated. see also the Perspective by Sondra Turjeman [ABSTRACT FROM AUTHOR]

Pomacea canaliculata is native to South America and has become a widely distributed agricultural and environmental pest in southern China. Previous studies have primarily focused on the tolerance of P. canaliculata to various environmental factors, and compared non-native invasive P. canaliculata with natives or non-invasive congeners. However, there has been no research concentrated on variation in innate growth and reproductive characteristics between P. canaliculata in its native and invaded areas. To address this gap, we conducted the first comparison experiment between P. canaliculata from their native area (Argentina) and from an invaded area (China). We recorded the temporal dynamics of shell height of male and female P. canaliculata, and investigated the sexual maturation and egg-related indicators in two populations from each country, rearing them under homogeneous temperature, photoperiod and food conditions. Our results showed that the shell growth rate of P. canaliculata in Argentina was significantly lower than that of P. canaliculata in China. Moreover, P. canaliculata exhibited stronger reproductive characteristics in populations from China, mainly reflected in the earlier sexual maturity, larger egg masses, higher hatching success, and a trend of shorter incubation period. These differences probably arose due to contemporary evolution in invaded areas under strong selective pressures in rice fields, and, together with more favorable climates, enable the snail populations to rapidly grow and expand in southern China. [ABSTRACT FROM AUTHOR]

Captive breeding programs are an increasingly important tool for species' conservation efforts, but not all species reproduce well in captivity. Identifying factors that affect the reproductive success of captive populations is crucial to improving the performance and management of conservation-breeding programs, both by providing individuals for release and informing decision making. We examined breeding records collected from the long-running conservation-breeding program for the critically endangered Orange-bellied Parrot Neophema chrysogaster over an 11-year period. We examined egg hatching rate, nestling survival rate, and offspring sex ratio in response to a wide range of variables related to characteristics of individual birds, breeding events, and the captive environment. The hatch rate of eggs was higher in first clutches compared to second clutches and was lower than the wild population. The survival rate of nestlings through to fledging was variable between years but became higher and more consistent over the last five years of the study period. Variation in brood sex ratio was not related to any of the potential explanatory variables that we examined. This is one of the first studies to examine reproductive data in a long-running conservation-breeding program and shows that many common metrics do not explain reproductive variation. Our approach provides a framework for managers to investigate factors affecting reproductive success in conservation breeding programs more broadly. [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]

Under the current ocean warming scenario, multigenerational studies are essential to address possible adaptive changes in phenotypic traits of copepod populations. In this study, we exposed the calanoid copepod Paracartia grani, reared in the laboratory at 19°C, to warmer conditions (22°C and 25°C) to investigate the changes in key phenotypic traits in the 1st, 10th, and 11th generations. Development rates and adult body size were inversely related to temperature in all generations. We also found a decline in copepod egg size at higher temperatures. Temperature had positive effects on the ingestion and egg production rate of females in the first generation, but the thermal response of the copepods diminished significantly in the consecutive generations. The decrease in thermal effects on feeding and egg production rates after multigenerational exposure cannot be explained only by the shrinkage in body size at warmer temperatures, but also involves the action of physiological compensation. These adaptive processes did not appear to have a significant cost on other traits, such as egg hatching success, gross growth efficiency, and sex ratio. Our findings have implications for the prediction of ocean warming effects on copepod activity rates and highlight the importance of physiological adaptation processes after multigenerational exposure. [ABSTRACT FROM AUTHOR]

The arboreal embryos of red-eyed treefrogs (Agalychnis callidryas) hatch prematurely to escape from egg predators, and escape success increases with age. We assessed developmental changes in the behavior and hatching performance of embryos attacked by wasps (Polybia rejecta) and their contributions to improved embryo survival. We recorded videos of 4- and 5-day-old embryos exposed to wasp attacks and determined each embryo's fate. For a stratified random sample of embryos that escaped and died, we determined the occurrence, sequence, and timing of events during wasp-embryo interactions. We constructed path diagrams of event sequences, tested for age effects on transition probabilities, and measured the durations of periods between key events. Overall, escape success was 38% higher in older embryos. They were more likely to hatch pre-emptively than younger ones, thus less likely to experience direct attacks, suggesting that developmental gains in mechanosensory sensitivity may increase hatching responses to indirect cues. During direct attacks, embryos were equally likely to be captured by wasps at both ages, and hatching speed was similar, suggesting no relevant difference in escape-hatching performance. After a wasp ruptured their egg capsule, older embryos were more likely to exit, and they did so much sooner; younger embryos remained in ruptured capsules for longer and were more likely to be attacked again. This developmental change in embryo behavior indicates decreased tolerance for egg-stage risk as the chance of tadpole survival increases, suggesting that ontogenetic adaptation to changing risk trade-offs contributes strongly to the developmental increase in escape success. Significance statement: As animals develop, both their abilities and the optimal strategies for antipredator defense change, and some show ontogenetic adaptation of defensive behavior. This is documented in the larval and juvenile stages but rarely examined during the embryonic period, when development is fastest. We document substantial changes in embryo behavior across a 1-day period following the onset of predator-induced hatching in red-eyed treefrogs, with rapidly decreasing tolerance of egg-stage risk contributing to higher survival under wasp predation as the costs of hatching decrease. This provides evidence for ontogenetic adaptation of defensive behavior in a natural predation context and across an earlier developmental period than previously known, thereby strengthening results from prior work with vibration playbacks across later developmental stages. It suggests that even during periods of rapid development of morphology and abilities, understanding behavioral decisions may be crucial to explaining changes in survival. [ABSTRACT FROM AUTHOR]