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This article presents the results of the study of ecological and biological characteristics of common carp (Cyprinus carpio Linnaeus, 1758) from Kapchagay Reservoir on the Ili River in Kazakhstan. We studied size-weight indices, body condition (Fulton condition factor), age structure, fecundity, and body length. We also determined the gonadosomatic index (GSI) during the spawning period. Fish samples were caught using fixed nets with mesh diameters ranging from 16 to 90 mm. Total body length (TL) in mm and total body weight (TW) of fish in grams were measured. A logistic regression model was used to determine body size at first maturity for females and males. Fecundity was determined in mature females (stage IV maturity). Calculation of the GSI made it possible to clarify the duration of the spawning period. This study provides important information about the troubling status of the population of C. carpio in the area of study and suggests effective approaches to regulate fisheries in the reservoir and other water bodies of Kazakhstan. There is clearly a need to limit IUU (illegal, unreported and unregulated) fishing and otherwise regulate over-fishing. [ABSTRACT FROM AUTHOR]

One of the Brachyura crabs found in the lower reaches of the Serayu River is Varuna litterata, also known as the "herring bow crab". This crab usually inhabits shallow tidal areas and hides under rocks, logs, or dead leaves. It is a highly adapted crab found in a wide range of salinities. V. litterata is also a fishery product consumed in Thailand, the Philippines, and Indonesia. This research was conducted in the Lower Serayu River, Central Java, which consists of three observation stations, namely: 1) the first station is located above the dam with fresh water, 2) the second station is below the dam with fresh water properties and 3) the third station is downstream (estuary) of the Serayu River with brackish water. This research was conducted for four months, from October 2023 to January 2024. This study aimed to determine the level of egg development in V. litterata. The results showed that V. litterata experienced four stages in egg development and then hatched into zoea. At the initial development stage, V. litterata eggs will be purple; in the second stage, the eggs will turn reddish; in the third development stage, the eggs will turn orange to brownish; and in the fourth stage, the eggs will develop and become black. V. litterata that will spawn will migrate to brackish waters to hatch their eggs. V. litterata produces 20,708 - 85,886 eggs with an average egg diameter of 0.440 - 0.466 mm. [ABSTRACT FROM AUTHOR]

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The presence of dams on the Columbia River (CR) has reduced Sockeye Salmon (Oncorhynchus nerka|sćwin) numbers to a fraction of their historic numbers. The Syilx Okanagan Nation Alliance (SONA) has led voices of concern regarding the impacts of diminishing Sockeye Salmon numbers on the ecosystem health of the sq,awsitkʷ|Okanagan River (s|OR), a tributary of the CR. In the early 2000s efforts commenced to rehabilitate the s|OR Sockeye population. These efforts have seen the population rise from a running average of 40,000 to 200,000. However, the contemporary spawning capacity of the s|OR is unknown, and this metric is critical to guide the conservation and restoration of this keystone species. We employed a spawning capacity model relating fish length and gravel size to spawning potential. We collected substrate data at 49 sites throughout our 37‐km study area, and used fish length and egg numbers from n = 269 Sockeye Salmon to establish s|OR specific fecundity metrics. The model estimated the s|OR has the capacity to support 147,687 (±33,346) Sockeye spawners, in its current condition. Whilst our model has limitations, we suggest a minimum escapement of 147,687 Sockeye spawners ought to be passed to the s|OR per annum. These fish will have broad ecosystem benefits and will be culturally beneficial to SONA peoples. Finally, continued restoration of s|OR habitat should enhance opportunities for Sockeye Salmon to continue their remarkable recovery. [ABSTRACT FROM AUTHOR]

BACKGROUND: Understanding how parasitoids respond to temperature is crucial for improving biological control strategies under the context of global warming. This study examined the suitability of Myzus persicae and its parasitoid Aphidius gifuensis to varying temperature conditions, as well as the stage‐specific response of A. gifuensis to high temperatures. RESULTS: High temperatures had a significant impact on the both M. persicae and A. gifuensis. When exposed to 36°C, M. persicae developed more slowly and produced smaller adults compared to control, regardless of the duration of exposure (2, 4 or 6 h); additionally, the survival rate of M. persicae nymphs sharply decreased under these conditions. Exposure to 36°C for 4 h negatively impacted the development of A. gifuensis. Female parasitoids exposed to 32°C developed into smaller adults, whereas males exposed to all three temperature levels were smaller compared to control group. Female parasitoids exposed to high temperatures, regardless of the specific heat level and duration, exhibited reduced longevity and decreased fecundity. None of the parasitoids exposed to 36°C for 6 h daily developed into adults. Heat treated during early developmental stages (2 and 4 days old) had a greater influence on parasitoid development, whereas heat treatment at 4 and 6 days old had a more significant impact on its fecundity. CONCLUSION: High temperatures not only directly affected the performance of A. gifuensis, but also exerted indirect effects by influencing the quality of the host aphids M. persicae. The deleterious effects of high temperature on larvae can persist into the adult stage, affecting the longevity and reproduction of adults. These findings are important for the utilization of A. gifuensis in the control of M. persicae in warming environments. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Saliva has a crucial role in determining the compatibility between piercing–sucking insects and their hosts. The brown planthopper (BPH) Nilaparvata lugens, a notorious pest of rice in East and Southeast Asia, secretes gelling and watery saliva when feeding on rice sap. Nlsalivap‐5 (NlSP5) and Nlsalivap‐7 (NlSP7) were identified as potential planthopper‐specific gelling saliva components, but their biological functions remain unknown. RESULTS: Here, we showed by transcriptomic analyses that NlSP5 and NlSP7 were biasedly expressed in the salivary glands of BPHs. Using the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9‐mediated genome‐editing system, we constructed NlSP5 and NlSP7 homozygous mutants (NlSP5−/− and NlSP7−/−). Electrical penetration graph assay showed that NlSP5−/− and NlSP7−/− mutants exhibited abnormal probing and feeding behaviors. Bioassays revealed that the loss‐of‐function of NlSP5 and NlSP7 significantly reduced the fitness of BPHs, with extended developmental duration, shortened lifespan, reduced weight, and impaired fecundity and hatching rates. CONCLUSION: These findings deepen our understanding of the BPH–host interaction and may provide potential targets for the management of rice planthoppers. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Biological information on Glyphocrangon spinicauda A. Milne-Edwards, 1881, a western Atlantic deep-sea armored shrimp, is scant. This species occurs in the Gulf of Mexico, but at low abundance, in the southern (Mexican) part. We obtained a sample of 203 G. spinicauda at depths of 244–455 m during a research cruise exploring the biota of the upper continental slope of the southeastern Gulf of Mexico, off the Yucatán Peninsula. We examined morphometric and allometric relationships of the shrimp as well as some reproductive traits based on the number and size of embryos. Sex ratio (1.4 females:1 male) differed significantly from unity. Females had significantly larger total length (TL) and total weight, but not carapace length (CL), than males, suggesting that females have proportionally larger abdomens. All morphometric relationships were significant for both sexes and most were linear. Relationships against CL were mostly isometric, but TL and rostral length exhibited negative allometry, i.e. a proportionally smaller increase with increasing CL. Brood size (BS) and embryo mass volume were linearly related with female size, but embryo development stage significantly affected BS, embryo size, embryo mass volume, and reproductive output. We found a significant, negative relationship between residuals of the number and size of embryos, suggesting a trade-off in embryo production. Although G. spinicauda is of no commercial value, it co-occurs with other species of potential interest. Our results can thus be useful to design management and conservation plans should fisheries for deep-sea resources eventually develop in the southern Gulf of Mexico. [ABSTRACT FROM AUTHOR]

Three new populations of the invasive New Zealand mud snail, Potamopyrgus antipodarum, have been discovered in central Chile, increasing the documented records in the country to 23. Only females were observed in the present study. Significant differences in shell length and fecundity were found among populations. The size of the snails was less than 6 mm, while fecundity varied from 0 to 45 offspring per snail. A significant correlation was found between adult shell length and brood size in one of the three populations discovered. In these localities, Potamopyrgus antipodarum coexists with native and possibly other invasive gastropods. [ABSTRACT FROM AUTHOR]

Broodstock nutrition is the most essential constituent of sustainable aquaculture production. Its impact on the reproductive performance and profitability of commercial aquaculture has been the subject of considerable research. The present paper reviews the literature available on the subject, examining the implication of Nile tilapia broodstock nutrition on parameters including maturation, fecundity, fertilization, embryo development, larval quality, and survival rate. The provision of a nutritive diet composed of essential macroand micronutrients including proteins, lipids, carbohydrates, vitamins, minerals, and functional additives, such as prebiotics, enzymes, hormones, and probiotics, in different proportions is discussed. Special emphasis is given to literature dealing with the effects of dietary protein and lipid on vitellogenesis and ovarian maturation, fecundity, egg hatching rate, larval quality, and fry survival number. The impact of the feeding regime on reproductive performance is described. [ABSTRACT FROM AUTHOR]

Body size is a trait that shapes many aspects of a species' development and evolution. Larger body size is often beneficial in animals, but it can also be associated with life history costs in natural systems. Similarly, miniaturization, the evolution of extremely small adult body size, is found in every major animal group, yet carries its own life history trade-offs. Given that these effects can depend on an animal's environment and life stage and have mainly been studied in species that are already specialized for their size, the life history changes associated with evolutionary shifts in body size warrant additional investigation. Here, we used Drosophila melanogaster populations that had undergone over 400 generations of artificial selection on body size to investigate the changes in life history traits associated with the evolution of extremely large and extremely small body sizes. Populations selected for small body size experienced strong trade-offs in multiple life history traits, including reduced female fecundity and lower juvenile viability. Although we found positively correlated changes in egg size associated with selection for both large and small body size, after adjusting for female body size, females from populations selected for large size had the lowest relative investment per egg and females from populations selected for small size had the highest relative investment per egg. Taken together, our results suggest that egg size may be a key constraint on the evolution of body size in D. melanogaster, providing insight into the broader phenomenon of body size evolution in insects. Graphical Abstract [ABSTRACT FROM AUTHOR]

To investigate the impact of sodium cyclamate on the fecundity, development, and locomotor abilities, this study using Drosophila melanogaster medium with varying concentrations of sodium cyclamate, the pupation time and total pupal count within a 5 d period were assessed as indicators of reproductive capacity. Additionally, the study analyzed the initiation of eclosion, the total number of emerged flies within 5 d, and the weight and body length of drosophila to elucidate the influence of sodium cyclamate on fruit fly development. The changes of locomotor abilities were evaluated in climbing index. The results revealed that a 1 mg/mL sodium cyclamate culture medium enhanced reproductive capacity, positively influenced the growth and development of Drosophila melanogaster, while reducing locomotor abilities. However, these effects did not reach statistical significant level. Conversely, sodium cyclamate concentrations ranging from 2 to 8 mg/mL exert inhibitory effects on reproduction, development, and locomotor abilities. The inhibitory effects became more pronounced with increasing concentration. Compared with 0, sodium cyclamate culture medium with concentrations ranging from 4 to 8 mg/mL exhibited significant differences in the reproductive, development and locomotor abilities（t=2.622 to 5.000, P<0.05）. Specifically, the 4 mg/mL sodium cyclamate culture medium led to a highly significant difference in the weight of female Drosophila melanogaster and the locomotor abilities of male Drosophila melanogaster （t=5.831 and 3.801, P<0.01）. The 8 mg/mL sodium cyclamate culture medium resulted in highly significant differences in the weight, length of female fruit flies, as well as the locomotor abilities of both female and male Drosophila melanogaster （t=9.970, 3.798, 8.994 and 10.451, P<0.01）. The results show that sodium cyclamate exhibit discernible effects on the reproduction, development, and locomotor abilities of Drosophila melanogaster. Caution should be exercised in their application in food production, and consumers should pay attention to the sweetener content for food safety considerations. [ABSTRACT FROM AUTHOR]

Pectinophora gossypiella one of the most destructive pests of Bt cotton. P. gossypiella gradually became a serious threat after gaining resistance to Bt toxin after 2 decade owing to which resulted in huge economic losses to the cotton growers. Present investigation was carried in order to study the most favourable temperature of P. gossypiella for its growth and development under various altering temperature regimes (20:30°C, 24:30°C,28:30°C, 20:35°C, 24:35°C, 28:35°C, 20:40°C, 24:40°C and 28:40°C) of Integrated Pest Management Laboratory, Department of Entomology, PAU, Ludhiana during cotton crop season 2022-23. Three models (linear and nonlinear) were used to estimate the relation between temperature and development rate of different instars and stages of P. gossypiella. The results revealed that duration of all larval instars and total larval duration were significantly short at an alternating temperature of 28:40°C. The pupal duration, adult longevity and total developmental period of male and female were recorded significantly low at the alternate temperature of 28:40°C. The fecundity and survivability (egg, larval and pupal)was significantly highest at 28:30°C, whereas the larval and pupal weights were significantly highest at an alternate temperature of 28:35°C. The correlation between developmental parameters and fecundity showed significant negative correlation. The survival of egg, larva and pupa showed non-significant negative correlation, whereas the larval and pupal weights show non-significant positive correlation with alternate temperatures. Stinner nonlinear and Inverse second order polynomial model provided more suitable temperature conditions for the development of P. gossypiella. [ABSTRACT FROM AUTHOR]

The wild population of Eutropiichthys vacha, Ompok pabda, Chitala chitala and Botio lohachata has been declined and is presently listed under threatened category owing to reduced abundance. A total of 308 samples of 4 threatened species representing three order and four families were procured during April 2019 to March 2020 from 6 different sites (Ghazipur, Jaunpur, Sultanpur, Barabanki, Lucknow and Sitapur) of River Gomti. A minimum of 10 female individuals were selected to study the biometry, health and absolute fecundity. In the present study, the value of regression coefficient (b) obtained via length-weight relationship showed high heterogeneity where a fish showed isometric (b = 3), negative (b < 3) to positive (b > 3) allometric growth patterns. Fulton's condition factor (K) was relatively found to be less than "1" which reflects the depletion in energy reserves except in B. lohachata collected from Jaunpur. The absolute fecundity varied from 1604 to 9049 and significantly different at the level of p < 0.001. In E. vacha, the "b" value ranges between 1.006–3.035, in O. pabda, the "b" value ranges between 2.628–3.469 and in C. chitala the "b" value was 2.426 and 3.255 and in B. lohachata the value of "b" was 3.180 which are considered to be the new record for fishdata base. The present study contributes the comparative description of growth pattern, well being and reproductive parameters of selected threatened fishes of River Gomti, India. The information gathered will be considered as baseline knowledge for future research to contemplate management strategies with reference to selected threatened fish species. [ABSTRACT FROM AUTHOR]

The article presents a comparative analysis of the fecundity of the Barents Sea red king crab, its size composition, and size at 50% maturity during the period of its expansion and acclimatization and at present during intense fishing. In addition, based on the published literature data, differences are estimated between the above parameters of Barents Sea individuals and individuals from the crab's natural habitat. In 2019–2022, the Barents Sea red king crab showed a trend of decreasing its fecundity compared to the period of active acclimatization (1995–2003) before commercial exploitation started. In recent years, changes in the reproductive parameters of the Barents Sea red king crab population have increased the similarity of these characteristics to those for native populations from the Pacific region that began to be actively exploited in the early 20th century. [ABSTRACT FROM AUTHOR]

Simple Summary: The study investigated how aging affects the reproductive potential and embryonic development of the pepper weevil (Anthonomus eugenii Cano), a major pest causing significant damage to pepper crops. The objective was to assess the reproductive parameters (fecundity, hatching rates, and developmental times) of weevils at different ages: young (10 days), middle-aged (20 days), and old (30 days). The results show that the age of pepper weevils significantly affects their reproductive potential, with younger weevils being more prolific. These findings are valuable for researchers as they highlight the importance of considering weevil age in pest management strategies, potentially leading to more effective cultural practices that reduce weevil populations and protect pepper crops. The pepper weevil (Anthonomus eugenii Cano) is a devastating pest that inflicts severe damage to pepper crops, leading to substantial economic losses. This study investigated the impact of aging on the reproductive success of the pepper weevil. Pepper weevil-infested fruit were harvested from pepper fields and subsequently transferred into an insect cage to facilitate the emergence of adults. The emerged adults were housed in separate cages and allowed to mature until they reached specified ages: 10 days old (young), 20 days old (middle-aged), and 30 days old (old) individuals. Eggs laid by each age group were carefully collected and incubated under controlled laboratory conditions (28 ± 1.5 °C). Several reproductive variables including the number of eggs laid, the percentage of hatched eggs, and the egg incubation period were recorded for each age group. Embryonic development was also monitored daily using a VHX digital microscope at a magnification of 200×. Differences in developmental stages such as the blastoderm, germ band, gastrulation, segmentation, and appendage formation were observed, and the time span of every stage was recorded. The results show that the 10-day-old weevils laid the most eggs and had the highest hatching rate and the shortest developmental time. The 30-day-old weevils laid the fewest eggs and had the lowest hatching rate and longest developmental time. Thus, the pepper weevil age significantly influenced the fecundity, length of time for each embryonic development stage, hatching rate, and incubation period, and should be considered when studying the reproductive biology of this pest insect. This first report of the effect of aging on the reproductive potential of the pepper weevil should enable pepper growers to adopt cultural practices aimed at reducing the pepper weevil populations, thereby helping to protect their crop from this important pest. [ABSTRACT FROM AUTHOR]

Aedes aegypti and Aedes albopictus are predominantly daytime-feeding mosquito species that breed in urban settlements and transmit viral and nematode diseases. Females can feed on a broad range of vertebrate hosts for oogenesis. Research on host-feeding behavior and patterns is important to better understand the transmission cycles of most mosquito-borne diseases and to develop better protection measures. This study investigated the host feeding patterns of Ae. aegypti and Ae. albopictus through both artificial blood feeding and natural feeding techniques and assessed the effect of these methods on mosquito fecundity. Laboratory colonies of both mosquitoes fed on blood from five different hosts (bird, mouse, human, sheep and cow). The artificial blood feeding system consisted of a glass condenser with blood attached to a water bath with warm water circulation and insects fed through a stretched Parafilm membrane over the bottom of the condenser. Natural feeding experiments were performed with paper cups that contained the mosquitoes and were placed over the host's skin for one hour. In the natural feeding method, Ae. aegypti females mostly fed on humans, while in the artificial blood feeding method, they fed on birds. Both human and bird blood sources yielded the highest number of eggs, larvae and pupae for Ae. aegypti. Aedes albopictus preferred humans in the natural feeding method and mice in the artificial blood feeding method. Similarly, egg, larvae and pupae productivity from humans and mice were also high for Ae. albopictus. Both species preferred the artificial feeding method. Our findings show that different blood meal sources and methods affect mosquito fecundity. Such laboratory studies on mosquito feeding patterns can reveal the feeding preference of important vectors and provide vital information for understanding vector and host interactions. [ABSTRACT FROM AUTHOR]

Background: Gonipterus platensis Marelli, 1926 (Coleoptera: Curculionidae) is one of the main defoliating beetles in Eucalyptus plantations. Biological control with egg parasitoids is one of the main control strategies for this pest and a constant supply of fresh host eggs is required to rear the parasitoids. Polyandry can influence Gonipterus oviposition by increasing female fecundity and fertility; however, the high density of individuals in laboratory colonies can lead to male harassment, resulting in lower reproduction rate. The aim of this study was to measure the effects of monoandry and polyandry on the reproduction of G. platensis and the effects of male harassment on laboratory rearing conditions. Methods: Reproductive parameters were compared between three treatments: monoandry, where the female was allowed to mate daily with the same male; no choice polyandry, where the female was allowed to mate daily with a different male; and polyandry with choice, where the female was allowed to mate daily, but with a choice between five different males. Another experiment varying the density of males was conducted to evaluate the effect of male harassment. Results: Polyandry with choice resulted in the longest period of oviposition, highest fecundity and highest number of eggs per egg capsules when compared to monoandrous females. No negative effect related to male harassment in the laboratory, such as decreased fertility, fecundity, or number of eggs per egg capsule, was detected. Conclusion: Polyandry contributes to mass rearing as it increases fecundity and oviposition period on females and there is no evidence of male harassment on G. platensis. [ABSTRACT FROM AUTHOR]

The size composition of the fish, gonadal condition, and oocyte and spermatozoon ultrastructure are studied in Parupeneus heptacanthus from the coastal zone of Nha Trang (southern Central Vietnam). The males are larger than the females, and the body length—body weight relationship is significantly different in the representatives of both sexes. Based on ovarian condition, oogenesis is continuous. Average batch fecundity is 11 056 oocytes. The egg envelope in the end of vitellogenesis (~300 µm in diameter) includes zona radiata 5.0 µm in width and chorion (0.5 µm). Based on spermatozoon head ultrastructure, the species is similar to other species of the genus Parupeneus, but the flagellum is substantially longer reaching on average 63 µm. [ABSTRACT FROM AUTHOR]

Host plants can strongly influence the population performance of insects. Here, we investigated the development, survival, and oviposition of Scirtothrips dorsalis Hood on 6 host plants— Camellia sinensis (L.) Kuntze (Ericales: Theaceae), Rosa chinensis Jacq. (Rosales: Rosaceae), Capsicum annuum L. (Solanales: Solanaceae), Eustoma grandiflorum (Hook.) G.Don (Gentianales: Gentianaceae), Glycine max (L.) Merr. (Fabales: Fabaceae), and Cucumis sativus L. (Cucurbitales: Cucurbitaceae), and constructed life tables for S. dorsalis on each plant. Significant differences in S. dorsalis development on the host species were observed. The mean developmental period from egg to adult was 11.45 ± 0.12 days, 11.24 ± 0.13 days, 12.08 ± 0.15 days, 12.28 ± 0.12 days, 12.67 ± 0.10 days, and 13.03 ± 0.11 days on C. sinensis , R. chinensis , C. annuum , E. grandiflorum , G. max , and C. sativus , respectively. Significant differences in survival of S. dorsalis were observed, namely, C. sinensis  ≈  R. chinensis  >  E. grandiflorum  ≈  C. annuum  >  G. max  >  C. sativus. The highest and lowest fecundities of S. dorsalis were recorded on R. chinensis (60.44 ± 1.53) and C. sativus (28.64 ± 1.02), respectively. Both of the net reproductive rate (R 0) and intrinsic rate of increase (r m) of S. dorsalis were the highest on R. chinensis , with the values of 27.63 ± 0.58 and 0.142 ± 0.002, respectively; while the lowest on C. sativus , with the values of 8.81 ± 0.12 and 0.092 ± 0.003, respectively. Thus, R. chinensis was found to be the most suitable host, but C. sativus was the least suitable, for population development of S. dorsalis. Our results provide important information for the key control of S. dorsalis among different host plants. [ABSTRACT FROM AUTHOR]

Sitobion miscanthi and Schizaphis graminum (Rondani) are the 2 main aphid species that occur simultaneously, causing significant loss to wheat production. Acetamiprid has been used to control a variety of pests, including aphids. In this study, the sublethal effect of acetamiprid on S. miscanthi and S. graminum was evaluated using life-table analyses. The results showed that acetamiprid has a high toxicity to S. miscanthi and S. graminum with a LC50 of 1.90 and 3.58 mg/L at 24 h, respectively. The adult longevity and fecundity of S. miscanthi and S. graminum F0 generation were significantly reduced after being exposed to a sublethal concentration of acetamiprid. Additionally, the sublethal concentration of acetamiprid had negative transgenerational effects on S. miscanthi and S. graminum , which showed a significant decrease in fecundity and population life-table parameters involving age-stage-specific survival rate (s xj ), age-specific survival rate (l x ), and intrinsic rate of increase (r). Furthermore, the population projections showed that the total population size of S. miscanthi and S. graminum was significantly lower in the aphid group exposed to sublethal concentration of acetamiprid compared to the control group. These results suggest that sublethal concentration of acetamiprid suppresses the population growth of S. miscanthi and S. graminum. This finding is beneficial to the control of wheat aphids, and is important to fully understand the role of acetamiprid in integrated pest management. [ABSTRACT FROM AUTHOR]

The population structure of endemic species arabian goby Сryptocentroides arabicus in Wadi Al‑Bahayes (Oman) (23°40′47″ N; 58°11′36″ E) was investigated using 259 fish sampled in August 2020 and August 2021. In this study, the growth and reproductive traits of C. arabicus were investigated. The length-weight relationship and Von Bertalanffy growth equation were as follows: W = 0.0271L2.3342, R = 0.8731, Lt = 20.14 (1 – e–0.1984(t – 0.053)). Spawning occurred between March and June. The average fecundity per individual was determined to be 1760 ± 186.5 number/(ind./year). According to the results, the species lives in a wide area in its habitat, although it shows negative allometric growth. Since the other species in the environment, introduce Poecilia latipinna and endemic-predator Aphaniops stoliczkanus, may face the negative effects, the habitat and itself must be protected. [ABSTRACT FROM AUTHOR]

Background: Energy allocation between growth and reproduction determines puberty onset and fertility. In mammals, peripheral hormones such as leptin, insulin and ghrelin signal metabolic information to the higher centres controlling gonadotrophin-releasing hormone neurone activity. However, these observations could not be confirmed in lower vertebrates, suggesting that other factors may mediate the energetic trade-off between growth and reproduction. A bioinformatic and experimental study suggested co-regulation of the circadian clock, reproductive axis and growth-regulating genes in zebrafish. While loss-of-function of most of the identified co-regulated genes had no effect or only had mild effects on reproduction, no such information existed about the co-regulated somatostatin, well-known for its actions on growth and metabolism. Results: We show that somatostatin signalling is pivotal in regulating fecundity and metabolism. Knock-out of zebrafish somatostatin 1.1 (sst1.1) and somatostatin 1.2 (sst1.2) caused a 20–30% increase in embryonic primordial germ cells, and sst1.2−/− adults laid 40% more eggs than their wild-type siblings. The sst1.1−/− and sst1.2−/− mutants had divergent metabolic phenotypes: the former had 25% more pancreatic α-cells, were hyperglycaemic and glucose intolerant, and had increased adipocyte mass; the latter had 25% more pancreatic β-cells, improved glucose clearance and reduced adipocyte mass. Conclusions: We conclude that somatostatin signalling regulates energy metabolism and fecundity through anti-proliferative and modulatory actions on primordial germ cells, pancreatic insulin and glucagon cells and the hypothalamus. The ancient origin of the somatostatin system suggests it could act as a switch linking metabolism and reproduction across vertebrates. The results raise the possibility of applications in human and animal fertility. [ABSTRACT FROM AUTHOR]

The study of reproductive biology is extremely crucial in fishery. Pachypterus atherinoides (Bloch, 1794) is a good food as well as an ornamental catfish in the World. The present study aims to examine the seasonal reproductive behavior of P. atherinoides regarding both its lentic and lotic ecosystems. The study was conducted over two years in selected lentic and lotic aquatic ecosystems of the Jhargram and Paschim Medinipur districts of West Bengal, India using the seasonally observed gonadosomatic index (GSI), fecundity, and gonad maturation stages for both habitats in the study area. The study reveals P. atherinoides to show single annual spawning between June-September. No significant difference was found regarding breeding period in terms of lentic and lotic aquatic ecosystems. This study can help aquaculturists regarding the culture, captive breeding, and conservation of P. atherinoides, as well as researchers regarding the biometric study of another fish. [ABSTRACT FROM AUTHOR]

The objective of this study is to provide information on the reproductive biology of tomato hind grouper, Cephalopholis sonnerati (Valenciennes, 1828) for conservation and management purposes. Fish caught by artisanal fishermen from September 2019 to August 2021 were analysed. A total of 280 females, 31 males, and 4 transitional and 178 sex‐undetermined fish were analysed. The female to male sex proportion was 9:1, and the fish reached a maximum total body length of 38.5 and 54.5 cm for females and males, respectively. The following microscopic stages were identified: immature, developing, ripe, running ripe/releasing, and spent in both males and females. Several asynchronous development patterns were observed in the studied gonads, including multiple oocyte stages and early and advanced stages of sexual transition. High gonadosomatic index (GSI) for both males and females was recorded in March, May, and November. Running ripe and releasing stages in females were identified in the months from March to June, which indicates the spawning season. The absolute and relative fecundity of the species ranged from 162,723 ± 207,267 and 239 ± 285, respectively. An exponential relationship was found between fecundity and total body length (TL), fecundity and total body weight (TW), and fecundity and gonad weight (GW). [ABSTRACT FROM AUTHOR]

Polymorphisms identified on the BMPR1B, BMP15, and GDF9 genes tend to increase multiple birth and ovulation rates in sheep. In the planned study, the productivity records of the flocks (approximately 41.000) collected from 2016 to 2022, belonging to the Public Breeding of Kangal Akkaraman Sheep in Sivas province TAGEM/58KAK2012-08 subproject of the Public Animal Breeding National Project, were used. Accordingly, the ear numbers of sheep that gave birth to at least two twins (n=96) and at least two singletons (n=96) were determined from 15 different farms relevant records. According to similar feeding characteristics, environmental variables were grouped as location, year-round feeding type, and seasonal feeding type. DNA groups were genotyped by the PCR-RFLP method for BMPR1B (FecB), BMP15 (FecXB, FecXG, FecXI, FecXH) and GDF9 (FecG) alleles. Accordingly, among the 6 SNPs examined, only the GDF9 gene-FecB SNP was determined polymorphic. Genotypic effect (FecB allele) and environmental effect variables (location, year-round feeding type, seasonal feeding type ) were also examined with a logistic model. It was determined that the relevant alleles and environmental variables did not have a statistically significant effect on the twinning phenotype. According to the results obtained, it was thought that the genes associated with multiple births in Kangal Akkaraman breed may have different variants specific to the breed. In addition, it is suggested that this character, which is affected by multiple genes, should be included in the planned breeding studies by considering the interaction of environmental variables and determining the variation of the related genes. In this respect, it is concluded that our study will guide the sequencing studies and multivariate analyses to be planned. [ABSTRACT FROM AUTHOR]

There are various modern pest-control management systems used in the current apple production, such as integrated pest management (IPM) or organic systems. All aims to support occurrence of natural enemies that should help to reduce populations of pests. Here we investigated the effect of fungicide-treated and fungicide-free (resistant tree varieties) treatment combined with biological, IPM, and conventional systems on spiders, as the major group of natural enemies occurring on foliage of apple trees. The biological treatment was based on the use of biopesticides; IPM system was based on the use of selective insecticides, conventional included the use of broad-spectrum insecticides. Abandoned plot served as a control. The study was done for three consecutive years. Spiders were sampled from canopies by beating at weekly intervals during season. We found that fungicide-treated plots had lower abundance of spiders for two years but not species richness than fungicide-free plots. Among the three pest-control management systems, IPM and conventional supported greater spider abundance but not species richness than the biological treatment. Comparison of spider abundance before and after insecticide applications revealed that only very few pesticides, particularly the broad-spectrum ones, reduced spider numbers. In addition, we focused on the comparison of three traits (body size, maturity, fecundity) among treatments. Of six species, only Philodromus cespitum showed a smaller body size on biological than the other treatments. There were three species in which adults occurred earlier on conventional treatment than on the other treatments. Neither clutch size of Phylloneta impressa nor egg size was different among treatments. The small though significant differences in abundance, richness, and selected traits, found among IPM, conventional, and biological treatments and the control show that these pest-control management systems had similar effect on spiders. Use of IPM system combined with scab resistant apple varieties is recommended. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the ecology considering distribution, abundance, population structure, and fecundity of the marine diplostraceans Penilia avirostris and Pseudevadne tergestina in the Veracruz Reef System National Park, southwest Gulf of Mexico. Surface samples were collected with a 300 µm mesh plankton net at 26 sampling sites in June, August, October (2011), May (2012) and June (2013). Temperature, salinity, and dissolved oxygen were measured in situ. The temperature range was 26.53 ± 0.41 and 29.29 ± 0.27°C, salinity between 33.43 ± 0.49 and 35.91 ± 0.09, and dissolved oxygen between 2.92 ± 0.08 and 6.56 ± 0.08 mg L-1 . P. avirostris and P. tergestina presented the highest density, with 2200 ind 100 m-3 in June and 5980 ind 100 m-3 in October, respectively. Four stages were determined in P. avirostris. In P. tergestina, there were five instars, with males in August and October. The size of parthenogenic females of P. avirostris was 773.4 ± 20.08 µm. In P. tergestina, it was 637.6 ± 49.28 µm. The number of embryos in P. avirostris was 2 to 7, and in P. tergestina, 2 to 8 embryos. The correlations between body length and the number of embryos in both species were statistically significant under the potential model (r > 0.68 for both species, P < 0.001). The transects with the highest abundance were the northern and the southern zones because they are far from the influence of the Jamapa River. The density of these crustaceans is related to optimal temperature, salinity, and dissolved oxygen values. The low proportions obtained from gamogenic individuals of P. avirostris and P. tergestina suggest that in tropical and subtropical regions, gamogenesis is not crucial for the life cycle of these organisms. [ABSTRACT FROM AUTHOR]

The silver pomfret fish Pampus candidus (Previously known as Pampus argenteus Euphrasen) was collected from Iraqi marine waters in the northwest Persian Gulf between April and December 2021, using gillnet and demersal trawling. The lengths and weights of fish were recorded, along with data on the initial maturity length, sex ratio, gonadosomatic index (GSI), Dobriyal index, gonad maturation, development cycle, and absolute fecundity rate. The forked length of female individuals varied from 248 to 281mm, whereas that of male individuals ranged from 124 to 194mm. In July, young fish began to appear. Male individuals had a somehow shorter period of sexual maturity compared to female counterparts. Furthermore, it is noted that males tend to be generally less in size compared to females. The length at first maturity female and male was recorded as 203 and 115mm, respectively. The sex ratio tends to increase for males, and there were two peaks in the rise of the gonadosomatic index and Dobriyal's index, which indicate two periods of spawning activity during June and September. Six stages of fish maturity have been identified, with differences in the size of the eggs. They had a long and continuous breeding season that lasted from May to November, and they spawned by releasing eggs in batches. Notably, they have two distinct reproductive periods: The first during May and June and the second during October and November. The relationship of fecundity with weight was found to be more representative than with length. The document mentions that the silver pomfret spawning and nursery areas are adjacent to the Shatt al-Arab discharge area. [ABSTRACT FROM AUTHOR]

Species recovery following anthropogenic disturbances will depend on adaptations in survivorship and fecundity. Life‐history theory predicts increased environmental stress will result in (1) shifts in resource allocation from fecundity to body growth/maintenance and (2) increased provisioning among offspring at the cost of reproductive output. For remnant populations that persist after forest harvesting, selection mediated through anthropogenic disturbances may affect resilience to additional stressors such as climate change. We tested how rapid changes in environmental conditions affected maternal investment strategies in two ground beetle species, Pterostichus pensylvanicus and Pterostichus coracinus, by comparing fecundity and survivorship in populations from recently clear‐cut and uncut habitats. Using parents drawn from clear‐cut or uncut stands, we reared progeny in both common garden and reciprocal transplant experiments. In P. pensylvanicus, we found that neither lineage nor rearing habitat affected the number of eggs laid per female or survivorship of offspring. However, eggs laid by females from clear‐cuts were more likely to hatch and offspring reached maturity more quickly, suggesting increased provisioning per offspring. In P. coracinus, females from clear‐cuts laid more eggs, and their eggs hatched more rapidly and had greater hatching success, suggesting increased investment in overall reproductive output and increased offspring provisioning. In the reciprocal transplant, we observed significant habitat by lineage interactions on survival in P. coracinus, with survivorship increasing when progeny were reared in novel habitats. In both species, increased maternal investment among offspring was not associated with a reduction in overall reproductive output, as anticipated. However, maternal investment among offspring declined with increasing female size, implying trade‐offs between increased metabolic demand and fecundity. Taken together, our work suggests that females from more stressful, clear‐cut habitats increased investment in fecundity, compared to females from uncut habitats, and may compensate for larval mortality. These changes were driven by smaller individuals, suggesting that increased environmental stress can influence the relationship between female size and maternal investment strategy. Additionally, reciprocal increases in offspring survivorship in habitats other than the parents suggest that adjacent areas between unharvested and clear‐cut habitat may be useful in maintaining biodiversity under future climate stressors. [ABSTRACT FROM AUTHOR]

The silkworm is an economically important insect known for its unique silk production. Oviposition is an important aspect of insect reproduction which needs in-depth study. The aim of this study was to determine the effect of the mating period on the fecundity, egg fertility, and performance of bivoltine silkworm (Bombyx mori L). Adult males and females were allowed to mate for 1, 2, 3, 4, 5, and 6 hours respectively. The eggs laid by the mother moth were acid treated, incubated, and subsequent hatched larvae were reared following standard protocols. The treatments were replicated five times and placed in a completely randomized design. Data were collected on female fecundity, egg fertility, larval and pupal weights, larval survival, and cocoon parameters. Data were subjected to analysis of variance and means were separated using DMRT (P <0.05). The results showed that the number of eggs laid, larval weight, number of cocoons harvested, shell ratio, and effective rate of rearing were significantly higher in progeny whose parents were allowed to mate for one hour. The cocoon weight, pupal weight, and shell weight were highest in progeny whose parents were allowed to mate for five hours, but not significantly different from the ones of other mating durations. There was a negative linear relationship between mating duration and hatchability (r=-0.88) at P<0.05. The study conclusively established that mating duration of one hour in bivoltine silkworms is enough to produce the best larval and cocoon performance. Hence, one-hour mating duration can be recommended for silkworm producers in the sericulture industry. [ABSTRACT FROM AUTHOR]

Simple Summary: Atractomorpha lata Motschoulsky (Orthoptera: Pyrgomorphidae) is a widespread phytophagous pest primarily found in the economic crop fields of Central Asian and Southeast Asian countries. Temperature plays a crucial role in determining its population growth and reproduction, and it is necessary to conduct in-depth research. We examined the developmental period of each stage and the number of eggs laid by female adults from the Yunnan Qujing population under different temperatures (16 to 32 °C). We calculated the developmental threshold temperature and effective accumulated temperature and constructed an age-stage-specific life table. The net reproduction rate (R0), total reproduction rate (GRR), and population trend index (I) were highest at 24 °C, which we identified as the optimal environmental temperature for the growth and reproduction of the Qujing population. Both high and low temperatures are not conducive to the survival and reproduction of its population. The results provide a scientific basis for predicting the potential distribution range, occurrence patterns in different regions, and field control strategies for this pest. Atractomorpha lata Motschoulsky (Orthoptera: Pyrgomorphidae) has recently emerged as an important agricultural pest in China. Understanding the impact of temperature on its developmental period is crucial for predicting its population dynamics. This study systematically observed the biological characteristics of A. lata at five temperatures (16, 20, 24, 28, and 32 °C) using the age-stage, two-sex life table method. The effects of temperature on the developmental period, survival rate, and fecundity of A. lata were studied using fresh bean leaves as host. The results demonstrated that as temperature increased from 16 °C to 32 °C, the developmental period, preadult time, adult longevity, adult preoviposition period (APOP), and total preoviposition period (TPOP) significantly decreased. The developmental threshold temperatures for various stages were calculated, ranging from 10.47 °C to 13.01 °C, using the linear optimal method. As temperature increased, both the intrinsic rate of increase (r) and the finite rate of increase (λ) also increased, while the mean generation time (T) decreased. The optimal values of the net reproductive rate (R0 = 54.26 offspring), gross reproductive rate (GRR = 185.53 ± 16.94 offspring), and fecundity (169.56 ± 9.93 eggs) were observed at 24 °C. Similarly, the population trend index (I) for A. lata peaked at 24 °C (61.64). Our findings indicate that A. lata exhibits its highest population growth rate at 24 °C, providing a scientific basis for predicting its population dynamics in the field. [ABSTRACT FROM AUTHOR]

Female fecundity is dependent on age and mated status. Young female insects accumulate considerable fat stores to fuel energetically expensive ovary development and egg production. Consequently, younger females are expected to have more stored fat than older females while the latter should have larger eggloads than the former. Mating is expected to increase fecundity because male ejaculates contain fecundity-enhancing substances that stimulate egg development, ovulation and oviposition. We experimentally tested the effect of female age (young versus old) and mated status (virgin versus mated) on fat and eggloads in female Gryllus firmus field crickets (Orthoptera: Gryllidae), in addition to testing the prediction that young or mated females have higher resting metabolic rates (RMR) than old or virgin females because the former should be significantly more engaged in the energetically expensive activity of egg production than the latter. As predicted, we found that young females had more fat and fewer eggs than old females and that fat loads negatively correlated with fecundity across all females. Young females also exhibited higher RMR, as expected if egg production is energetically costly. Contrary to expectation, however, mated status had little effect on fat load, egg production or RMR. That mating had little effect on total egg production (i.e. stored and oviposited eggs) challenges the hypothesis that male fecundity-enhancing substances in the ejaculate stimulate egg production. Our experiment also permitted us to examine the validity of two popular indices of body condition, the scaled mass index (SMI) and residual body mass (R i). Neither index accurately represented the true treatment effects of age and mated status on fat load; however, the SMI reflected true fat content in young, but not old, females. • We tested effects of age and mated status on fat and eggloads in female Gryllus firmus. • Young females had more fat and fewer eggs than old females. • Fat loads were negatively correlated with fecundity across all females. • Young females had a higher resting metabolic rate (RMR) than old females. • Mated status had little effect on fat load, egg production or RMR. [ABSTRACT FROM AUTHOR]

Purpose. To carry out a retrospective analysis of changes in the state of the white Dniester crayfish population (Pontastacus eichwaldi bessarabicus Brodsky, 1967) in the Dniester estuary. To provide a description of its abundance and range in this water body. To analyze changes in the main biological characteristics of this species at the population level in the estuary. Methodology. The material for the study was collected from the catches of commerical fishing gear during the crayfish fishery in the Dniester estuary in the period from 2017 to 2021. A complete biological analysis of the obtained material was carried out in the laboratory of the Department of Aquatic Bioresources and Aquaculture of the Odessa State Ecological University (OSEU). The total length of crayfish, their weight, absolute and working fecundity of females, egg diameter, size and weight characteristics of larvae and juveniles were determined. The feeding of crayfish in ontogeny was studied. To assess the reproductive capacity of the crayfish population in the Dniester estuary, we used the coefficient of fecundity preservation Ki calculated on the basis of the obtained data. Statistical data processing was carried out using MS Excel spreadsheets. Findings. In 1950-2021, the range of the population of the Dniester white crayfish in the Dniester estuary decreased from 13 to 7‒8 thousand hectares, and its total stock -- up to 200±50 thousand individuals. At the same time, the average density of this crayfish was 17-18 ind. per hectare of the estuary. In recent years, more than 60% of the water area, in which the population of white Dniester crayfish is found in the estuary, is located within the Lower Dniester National Nature Park. In addition, the size and weight of crayfish in the estuary have decreased in recent years. For example, in the 1960s and 1970s, up to 40-45% of individuals were characterized by a length of 13.5-16.5 cm. In 2017, the modal group consisted of individuals with a length of 9-9.5 cm, and in 2019-2021 -- 9.6-10.0 cm. The maximum size of crayfish in 2019-2021 was 14.5-15.0 cm (19‒20 cm in 1960-1970s). The reproductive capacity of the population also deteriorated. Absolute and working fecundity decreased. The Ki coefficient for the population of this species in the Dniester estuary in 2017-2018 was 0.63, and in 2020-2021 it was 0.53. This indicates a progressive decrease in the abundance of its population. Originality. For the first time in the last 25‒30 years, an assessment of the current state of the Dniester white crayfish population is given. The analysis of the available data indicates the progressive degradation of the population. A decrease in the range of distribution of this species in the estuary, a decrease in its size, the share of females in the population, and indicators of their fecundity were recorded. A decrease in the coefficient of preservation of fecundity Ki indicates a depressed state of the Dniester white crayfish population in the estuary, which threatens its further degradation. In recent years, catches of white Dniester crayfish in the Dniester estuary have decreased significantly. For example, the catch per fyke net does not exceed 1.0-2.0 kg, and the share of individuals of non-commercial size (up to 10 cm) has increased significantly. Practical Value. The research results allowed: providing an ecological and biological characterization of the state of the Dniester white crayfish population in the Dniester estuary; characterizing changes in the abundance and spatial distribution of crayfish in this water body; highlighting the peculiarities of its biology; determining the strategy of restoration and rational use of the natural population of crayfish, becoming an opportunity during the development of effective methods of its artificial reproduction. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mating is an essential factor that governs the size of insect populations that reproduce sexually. The extensive application of insecticides has both lethal and sublethal effects on the physiology and mating behavior of insect natural enemies. The predatory bug Cyrtorhinus lividipennis is a natural enemy of planthopper and leafhopper populations in the rice ecosystem. Unfortunately, the effects of insecticides on the mating behavior of C. lividipennis are not well‐understood. RESULTS: The mating behavior of C. livdipennis consisted of mounting, antennal touch and mating attempts, genital insertion, adjustment of posture, and separation of the mating pair. Approximately 82.5% of the C. lividipennis mating pairs displayed their first mating at 12–36 h postemergence. Mating activity occurred throughout a 24‐h period, with peak activity at 12:00–14:00 h, and the mean duration of mating was 48.75 min. Sublethal exposure to imidacloprid increased mating latency. Compared with the controls, the duration of courtship, pre‐mating and adjusting posture for males treated with imidacloprid were prolonged. The duration of mating for females treated with imidacloprid was prolonged relative to untreated controls. The fecundity and daily spawning capacity of females treated with imidacloprid were higher than the untreated controls. CONCLUSION: Our results provide insight into the mating process of C. lividipennis. Imidacloprid prolonged the duration of mating, which may explain the enhanced reproductive output in C. lividipennis females treated with imidacloprid. These findings will be useful in both rearing C. lividipennis and deploying this natural enemy in rice fields. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

AbstractBiometric measurement provide crucial information on fish growth and aquatic habitat well-being. This study offers the first comprehensive elucidation on biometric indices and reproductive biology of Cyprinus carpio var. communis in Lake Arekit (Ethiopia). A total of 209 fish were collected (ranging between 8.8 and 51.3 cm in total length (TL), while 16.99–2,498.3 g total weight (TW)) using gillnets during June 2022 to May 2023. The overall sex ratio (male, M; female, F) was 1:0.66 and significantly varied from the hypothetical sex ratio (1:1) (χ2 = 8.85, p

Sheep litter size is a critical trait in mutton production. While litter size regulation in relation to DNA transcription have been rigorously investigated, the function of RNA editing remains less explored. To elucidate the mechanisms controlling sheep fecundity at the RNA editing level and identify pivotal RNA editing sites, this study scrutinised RNA editing sites (RESs) in follicular and luteal phases of ovaries from sheep with high and low fecundity, and the functions of population-specific RESs were subsequently analysed. A total of 2 182 475 RESs, 74.61% of which were A-to-I and C-to-U sites, were identified. These RESs were fairly evenly dispersed over the chromosomes, with 46.8% showing close clustering (inter-site distance < 300 bp). Notably, 93% were primarily situated in intronic and intergenic regions. In the follicular phase, pivotal RESs were found in the introns of genes including LPS responsive beige-like anchor, MCC regulator of Wnt signalling, and RWD domain containing 3, among others, and in the exon region of EvC ciliary complex subunit 2. In the luteal phase, RESs were observed in the introns of genes such as H/ACA ribonucleoprotein assembly factor and SDA1 domain-containing 1, and the exon and 3′UTR regions of polypeptide N-acetylgalactosaminyltransferase 15 and ilvB acetolactate synthase-like, respectively. High-fecundity sheep showed RESs in the follicular phase in genes such as fibrillin 1, cyclin−dependent kinase 6, and roundabout 1, and in genes such as autophagy−related 2B and versican in the luteal phase. Thirteen RESs specific to the follicular phase and eight specific to the luteal phase were identified in high-fecundity sheep ovaries. These RESs offer promising molecular targets and enhance understanding of multiple births in sheep from the perspective of posttranscriptional alterations.

The present study focused on investigating the population structure and breeding biology of a species of Porcellanid crab, Petrolisthes boscii (Audouin, 1826). Evaluating the population ecology of the species is essential considering its crucial role in ecological functions including the nutrition cycle and its potential vulnerability to environmental stressors. The samples were collected over a period of 12 consecutive months (from March 2019 to February 2020) in an area of 500 m2 during low tide, utilizing the catch-per-unit-effort (CPUE) method when the water receded. The collected specimens (859 individuals) were categorized into males (407 individuals), non-ovigerous females (452 individuals), and ovigerous females (303 individuals). The assessment of fecundity was conducted by measuring the egg characteristics, including the total number, size, and weight of the eggs, as well as the carapace width of the ovigerous females. There was an evident difference in size, with males (8.60 ± 2.76) being significantly larger compared to females (8.39 ± 2.46) (p < 0.001). The overall and monthly sex ratios were female-biased (1:1.17). Moreover, the size frequency distribution revealed a bimodal distribution in male as well as female individuals. Ovigerous females occurred in all the months, which shows that the species breeds continuously throughout the year, with peaks in the months of March to May and August to October. There was a significant positive relationship observed among the size of ovigerous females and their total number of eggs (130.39 ± 83.31), egg mass weight (150 ± 110 mg). The study may provide baseline information for future studies on the impacts of a continuously altering environment and the consequences of increasing anthropogenic pressure on coastal areas.

Encarsia sophia is the dominant parasitoid of invasive whitefly pest such as Bemisia tabaci. This heteronomous hyperparasitoid species lays fertilised diploid eggs in whitefly nymphs, which serve as primary hosts. Larvae develop as female progeny by consuming whitefly hosts, providing direct biocontrol benefits. However, male progeny originate from unfertilised eggs laid on secondary hosts (primary parasitoids within whitefly nymphs) and develop by consuming primary parasitoid larvae rather than whitefly hosts. Therefore, it is crucial for indoor rearing and field release of the hyperparasitoid to determine whether a female with single-mating experience can parasitise primary hosts and produce female progeny for a whole lifetime and, if not, whether it is remating events and prolong the period of female production, thereby increasing the amount of parasitism on whiteflies. Our fecundity experiments of females with single-mating experience, equally provided with primary and secondary hosts, showed that single mating was insufficient for E. sophia females to lay fertilised eggs in whitefly nymphs for their whole lifetime. In multiple mating experiments, 76.7 % of male adults completed their second mating 2 h after the first, whereas female adults accepted the second mating only if primary hosts were available thereafter. Remating was beneficial for female adults as it prolonged the ovipositional period of fertilised eggs (from 13.3 ± 0.6 days for single to 17.1 ± 0.7 days for twice mating) and increased parasitism on B. tabaci primary host (from 53.1 ± 3.8 for single to 76.4 ± 5.9 for twice mating respectively). The mating experience of males increased their copulation success, whereas that of females decreased it. In conclusion, recommendations are provided for large-scale indoor rearing and field release of E. sophia. Firstly, sufficient time for providing males can be shortened to within 2 h, and a single male can engage in 2–3 mating sessions. Following the 15-day peak oviposition period, the addition of newly emerged males is advised. Secondly, for field release of adult parasitoids, it is recommended to concentrate on releasing females after completing mating indoors. For the release of pupae cards, ensure a balanced ratio of males and females on each card to facilitate mating upon emergence. Additionally, release extra males and females 2 weeks after the initial batch of releases.

Abstract Male‐biased sexual size dimorphism (SSD) is common in ungulates. The dominant scenario for the evolution of ungulate SSD suggests that habitat openness leads to greater SSD by increasing group size and thus sexual selection through male–male competition for mates. At a more proximate level, adaptive changes in SSD may result from the plastic response of individuals to environmental variation. In this study, we used 161,948 body mass data from a seasonally size‐dimorphic species, the northern chamois Rupicapra rupicapra, to examine the role of forest cover and other environmental variables in the expression of SSD. Data were collected from individuals hunted in the Austrian Alps, grouped into 28 mountain ranges with different forest cover, geological substrate and population density. Population‐specific growth curves were fitted using monomolecular models, and SSD was calculated as the log‐transformed ratio of male to female asymptotic body mass. A path model in which environmental factors indirectly influenced SSD via male or female body mass suggested that SSD increased with increasing density via reduced female body mass and decreased on siliceous substrates via reduced male body mass. Forest cover was negatively associated with body mass in both sexes, but not with variation in SSD.

Reproduction is a fundamental biological process that is essential for the continuous survival of fish species. Understanding their early life history and reproductive biology can explain how the population behave over time. A total of 1,238 fish samples were examined to determine the reproductive patterns and period of fringescale sardinella (Sardinella fimbriata) from Malampaya Sound, Palawan, Philippines. Monthly sampling from April 2023 to March 2024 revealed a 1:1 sex ratio. Gonadal examination of the fish revealed the presence of spawning individuals throughout the study period. The minimum size of matured fish observed was 11.0 cm and 11.1 cm for male and female S. fimbriata, respectively. The peak of spawning was April as indicated by the highest calculated GSI of 7.62% and fecundity of 18,465. A smaller peak was again observed in the month of September. The length at maturity was estimated to be 11.4 and 8.8 cm for males and females, respectively. Fecundity ranged between 2,700 to 36,067 eggs per spawn for size class between 11.1-14.8 cm and weight 13.07-31.93 g. Regression analysis between fecundity and morphometric characteristics such as body length, weight, eviscerated weight, and gonad weight revealed a positive correlation. Very low coefficients of determination were computed, ranging between 0.0028-0.1233. A significant association between fecundity and the morphometric variable gonadal weight was observed, as shown by the p-value of 0.0000. These outcomes are valuable data in the formulation of conservation and management strategies for the area. Implementation of appropriate conservation measures, monitoring of environmental parameters, strict enforcement of fishery regulation, coupled with increased environmental awareness and community participation will guarantee the long-term sustainability of the fringescale sardinella population and the preservation and sustainable use of marine biodiversity in Malampaya Sound.

Caragobius urolepis has a wide range of distribution, from brackish to freshwater water, ranging from India to the Philippines and Fiji, including the Vietnamese Mekong Delta (VMD), where it lives mainly in the coastal regions and plays a vital role in food supply. Our preliminary observation showed that its population tended to decline, but little is known about this species. This study, therefore, was conducted to provide data on the ovarian structure, spawning pattern and season, length at first maturity, and batch fecundity of this fish. The study of 306 specimens caught with trawl nets from April 2022 to March 2023 in two coastal areas of VMD—Dong Hai, Bac Lieu (DHBL), and Dam Doi, Ca Mau (DDCM)—showed that this goby spawned more than once because the oocytes in stage IV ovary showed different stages of development. It could release eggs monthly during a 12-month study, with a peak in July–September since stage IV ovaries were found monthly during the study period and the GSI exhibited a high value in July–September. The fish length at first maturity and batch fecundity varied with the site, as they were 18.8 cm and 3,757–9,187 (6,142 ± 707 SE eggs/female) in DDCM and 20.5 cm and 3,760–11,118 (5,634 ± 750 SE eggs/female) in DHBL. The findings provide valuable foundations for exploiting their resources and serve as a basis for studying artificial reproduction. It is suggested to avoid catching these fish species during the breeding season to ensure sustainable exploitation in the future.

Fish of the genus Tlaloc are distributed from southern Mexico to Central America and are a distinctive example of the endemic fauna of the Mesoamerican highlands, which has been scarcely studied in Mexico. The present study provides basic life-history data for the species Tlaloc hildebrandi, T. candalarius, and T. labialis, which are native to the headwaters of the Grijalva-Usumacinta basin in southeastern Mexico. We collected 918 specimens to determine their Length-Weight Relationship (LWR), Relative Condition Factor (Kr), sex ratio, Gonadosomatic Index (GSI), fecundity, and size at first sexual maturity. Both sexes of all species had positive allometric growth, except for T. candalarius females (isometric). Mean Kr and sex ratio values differed significantly among species. Females’ GSI values differed significantly among species but were highest during the dry season in all three species. Absolute fecundity was positively correlated with standard length and weight. Sexual maturity was reached at different lengths among species. Based on these results, we suggest that all three species present an opportunistic life strategy, which is very common in fish of the order Cyprinodontiformes. These results represent a first contribution on the life-history of this group of fish and provide basic information that is fundamental to ensuring their conservation.

The cattle production system focuses on maintaining an animal-based food supply with a lower number of cattle. However, the fecundity of dairy cows has declined worldwide. The reproductive tract microbiome is one of the important factors which can influence bovine fecundity. Therefore, reproductive tract microbiomes have been explored during the estrus cycle, artificial insemination, gestation, and postpartum to establish a link between the micro-communities and reproductive performance. These investigations suggested that microbial dysbiosis in the reproductive tract may be associated with declined fertility. However, there is a scarcity of comprehensive investigations to understand microbial diversity, abundance, shift, and host-microbiome interplay for bovine infertility cases such as repeat breeding syndrome (RBS). This review summarizes the occurrence and persistence of microbial taxa to gain a better understanding of reproductive performance and its implications. Further, we also discuss the possibilities of microbiome manipulation strategies to enhance bovine fecundity.

Previous studies have suggested that traffic-related air pollution is associated with adverse fertility outcomes, such as reduced fecundability and subfertility. The purpose of this research is to investigate if PM2.5 exposure prior to conception or traffic-related exposures (traffic density and distance to nearest major roadway) at birth address is associated with fertility-assisted births. We obtained all live and still births from the Massachusetts state birth registry with an estimated conception date between January 2002 through December 2008. All births requiring fertility drugs or assisted reproductive technology were identified as cases. We randomly selected 2000 infants conceived each year to serve as a common control group. PM2.5 exposure was assessed using 4 km spatial satellite remote sensing, meteorological and land use spatiotemporal models at geocoded birth addresses for the year prior to conception. The mean PM2.5 level was 9.81 µg m-3 (standard deviation = 1.70 µg m-3), with a maximum of 14.27 µg m-3. We calculated crude and adjusted fertility treatment odds ratios (ORs) and 95% confidence intervals (CI) per interquartile range of 1.72 µg m-3 increase in PM2.5 exposure. Our final analyses included 10 748 fertility-assisted births and 12 225 controls. After adjusting for parental age, marital status, race, maternal education, insurance status, parity, and year of birth, average PM2.5 exposure during the year prior to conception was weakly associated with fertility treatment (OR: 1.01; 95% CI: 0.97, 1.05). Fertility-assisted births were inversely associated with traffic density (highest quartile compared to lowest quartile, OR: 0.92; 95% CI: 0.83, 1.02) and positively associated with distance from major roadway (OR per 100 m: 1.01; 95% CI: 1.00, 1.02) in adjusted analyses. We did not find strong evidence to support an adverse relationship between traffic-related air pollution exposure and fertility-assisted births.

Western flower thrips, Frankliniella occidentalis (WFT), is one of the most destructive insect pests of vegetables and ornamental crops globally. Ultraviolet-C (UV-C) exposure has been shown to reduce populations of arthropod pests, including whiteflies and two-spotted spider mites, but has not been fully assessed for WFT. The goal of this study was to determine if UV-C radiance could be a viable strategy for inclusion in integrated pest management (IPM) programs for WFT. The objectives were to (1) assess the relationship among UV-C dose (irradiance × duration) and mortality of WFT adults and second instar larvae, (2) determine the effect of UV-C on WFT fecundity and egg hatch, and (3) assess the effect of the WFT lethal dose of UV-C on three WFT-prone ornamental plants. A UV-C dose is measured in Joules, which equals power (watts) × exposure time. A dose-dependent relationship between UV-C exposure and mortality of WFT larvae and adults was observed. At the doses of 0.98 and 0.68 J/cm2 (5 and 4 min exposure, respectively), 50% of the larvae died within 24 and 48 h, respectively. The UV-C dose needed to achieve 50% mortality was higher for adults than larvae, occurring at 5.2 and 4.4 J/cm2 (35 min and 25 min exposure, respectively) within 72 and 120 h, respectively. The number of eggs laid by surviving WFT subjected to UV-C treatment was less than by those that were untreated, and the egg-laying period was significantly shorter among those treated with UV-C. When leaves containing WFT eggs were exposed to UV-C doses known to cause 30–40% mortality in adults, 86–98% fewer eggs hatched compared to untreated controls. Ornamental plants exposed to UV-C doses lethal to eggs, second instars, and adult WFT either showed no damage, or when damage occurred, plants recovered within 14–30 days. Additional studies under controlled greenhouse conditions are needed to elucidate the effectiveness of UV-C radiance against WFT over time and its compatibility with biological control and other IPM practices.

Polymorphisms identified on the BMPR1B, BMP15, and GDF9 genes tend to increase multiple birth and ovulation rates in sheep. In the planned study, the productivity records of the flocks (approximately 41.000) collected from 2016 to 2022, belonging to the Public Breeding of Kangal Akkaraman Sheep in Sivas province TAGEM/58KAK2012-08 subproject of the Public Animal Breeding National Project, were used. Accordingly, the ear numbers of sheep that gave birth to at least two twins (n=96) and at least two singletons (n=96) were determined from 15 different farms relevant records. According to similar feeding characteristics, environmental variables were grouped as location, year-round feeding type, and seasonal feeding type. DNA groups were genotyped by the PCR-RFLP method for BMPR1B (FecB), BMP15 (FecXB, FecXG, FecXI, FecXH) and GDF9 (FecG) alleles. Accordingly, among the 6 SNPs examined, only the GDF9 gene-FecB SNP was determined polymorphic. Genotypic effect (FecB allele) and environmental effect variables (location, year-round feeding type, seasonal feeding type ) were also examined with a logistic model. It was determined that the relevant alleles and environmental variables did not have a statistically significant effect on the twinning phenotype. According to the results obtained, it was thought that the genes associated with multiple births in Kangal Akkaraman breed may have different variants specific to the breed. In addition, it is suggested that this character, which is affected by multiple genes, should be included in the planned breeding studies by considering the interaction of environmental variables and determining the variation of the related genes. In this respect, it is concluded that our study will guide the sequencing studies and multivariate analyses to be planned.