Feeding Habits Research Articles

A multiplex qPCR followed by high‐resolution melting analysis for the detection of blood‐feeding sources in Culex sp. mosquitoes

AbstractCulex species, such as Culex quinquefasciatus and Culex nigripalpus display a range of feeding habits and act as vectors for pathogens that can cause diseases in both humans and animals. Understanding their feeding habits is pivotal for enhancing disease prevention strategies. The present study introduces the application of two multiplex real‐time PCR (qPCR) followed by high‐resolution melting (HRM) as a cost‐effective and time‐efficient alternative. This investigation involved the development of two multiplex qPCR‐HRM: assay 1 detects human, dog and chicken, while assay 2 detects cat, cattle and horse in Culex sp. engorged female mosquitoes. The qPCR‐HRM reactions showed a detection limit of one copy of genomic DNA when performed as single and multiplex qPCR‐HRM. The reaction efficiencies were 97.96% for human, 100.60% for dog, 99.03% for chicken, 99.92% for feline, 99.18% for cattle and 97.68% for horse. The qPCR‐HRM method, employing multiplex 1 and 2, was applied to field‐collected mosquitoes and demonstrated the ability to detect DNA from multiple blood sources within a single sample. By analysing both multiplexes, it was possible to identify up to five distinct blood sources in Cx. quinquefasciatus and Cx. nigripalpus, and up to two sources in Culex coronatus. Sequencing corroborated the qPCR‐HRM results, confirming the presence of DNA from one to four different blood sources with 100% accuracy. The development of these molecular methods may contribute for identification of blood‐feeding patterns in mosquitoes. It contributes to studies on the dissemination and transmission of pathogens among various animals and humans, thereby bridging the gap between epidemiology and vector monitoring.

Impact of Seasonal Changes on Avifauna Diversity in Nguru Wetland, Yobe State, Nigeria

The research on impact of seasonal changes on avifauna diversity in Nguru Lake of Hadejia-Nguru Wetland was carried out in two different seasons for the period of six 6 months, from April to June (dry season) and July to September (wet season). The aim was to evaluate the impact of seasonal changes on avifauna diversity and the species richness in the study area. A reconnaissance survey was carried out to select study sites and sampling points. Five (5) different points were selected which comprises of Madauka, Kayayyashi, Farin Ruwa, Badum and Guzan respectively and Point count census techniques were adopted. In each counting station, bird observation was carried out twice daily; morning between 6:00 am and 10:00 am and evening between 4:00 pm and 6:00 pm. Data compilation was done using Microsoft Excel and were analysed using statistical software Past 326b. Bird diversity was calculated using Shanon-Weiner diversity index. The findings of this research showed that the majority of birds identified were Resident species (12,225 individual birds), Migratory species (8,186 individual birds) and Palearctic Migrants (10,876 individual) species in the study area. Dominant bird species in Nguru lake were Philomachus pugnax, Actophilornis africanus and Phalacrocorax africanus. A total of 5,538 individual birds’ was identified (Dry Season) in Nguru lake ‘’ belonging to 21 families in which Ardeidae family had the highest (7) species of bird. Shannon Diversity Index’ has 2.55 in dry season, while in Wet Season’ has 3.40. This indicated that there was relatively equal and high diversity of bird species in Wet Season in the study area and has the total species richness of 6,711. Overgrazing and other anthropogenic activities which affect the population diversity of avifauna species serve as major threats to the continued existence of Wetlands. Typha grass also remained pressing problem which create microhabitats reducing critical habitat for feeding, nesting and roosting habitat for birds, as well as hampers the smooth flow of water used by many water bird species. In view of the findings of this study, effective monitoring and strategies for conservation to restore the population of bird species, provide public enlightenment of the people around the wetland and management of Hadejia-Nguru Wetland promptly advice the significant importance of the wetland in serving as home for resident and migratory birdspecies.

The Future Migration Direction of Deer and Japanese Yew Is Consistent Under Climate Change

Climate change is becoming an important driver of biodiversity loss by altering the habitat, distribution and interspecific relationships of species. Japanese yew (Taxus cuspidata) is a first class protected plant in China, which has important ecological significance and occupies a certain position in the feeding habit of wapiti (Cervus elaphus) and Siberian roe deer (Capreolus pygargus). Due to human and animal damage, the number of Japanese yew has gradually decreased. Therefore, understanding the potential distribution of Japanese yew and the suitable areas for deer to browse on it under climate change will help to further protect these three species in Northeast China, especially migrate to more suitable areas in different scenarios in the future. From July 2021 to July 2024, we collected the information of species distribution and the variables associated with the species’ ecological limits in Muling National Nature Reserve to cross-reflect the current and future distribution and feeding area of the two species to assess each other’s impacts with Maximum entropy model (MaxEnt). The results showed that under the SSP2-4.5 and SSP5-8.5 scenarios, feeding pressure, driest quarter precipitation (BIO17) and seasonal temperature variation coefficient (BIO4) were the main variables affecting the distribution of Japanese yew, and the driest quarter precipitation (BIO17) and annual precipitation (BIO12) were the main variables affecting wapiti and Siberian roe deer foraging them. Under SSP2-4.5 and SSP5-8.5 scenarios, the suitable area of Japanese yew and the feeding area of the two species of deer gradually decreased from 2041 to 2100. Compared with wapiti, Siberian roe deer has a greater impact on the distribution range of Japanese yew, and the suitable feeding area is wider. It is expected that the potential centroid of Japanese yew, wapiti and Siberian roe deer will migrate to higher latitudes in the future. These findings provide a scientific basis for the reserve to develop relevant measures and plans and effectively protect the three species.

Essential and non-essential elements in the endemic Peppered catshark Galeus piperatus of deep-ocean waters from northern Gulf of California: Baseline levels and Se ratios

In this study the levels of As, Cd, Cu, Hg, Pb, Se, Zn and Se:Hg molar ratios, in muscle and liver of the endemic catshark Galeus piperatus from the northern Gulf of California (NGC) and relationships with biological parameters, were determined. Arsenic presented the highest levels for both tissues and Pb the lowest. The Se:Hg molar ratios were >1. Sex was not a determining factor in accumulation of elements. The differences in the levels of the studied elements between tissues might be due to their physiological functions and the availability of the metal(loid)s. The diet was considered as an important contribution pathway of these elements despite the fact that G. piperatus feeding habits are still unknown. More research is necessary to clearly understand the interactions between the biology of G. piperatus and the bioavailability of the studied elements and use this endemic shark species as a potential deep-sea biomonitor in NGC.

Transport of ‘Nama’‐type biota in sediment gravity and combined flows: Implications for terminal Ediacaran palaeoecology

ABSTRACTThe lower Nama Group in southern Namibia contains trace fossils and soft‐bodied and biomineralized macro‐organisms from the terminal Ediacaran Period (ca 550 to 539 Ma), offering insights into early metazoan evolution. Interpretation of the fossilized Nama Group organisms as being preserved in, or very close to, the environments in which they originally lived has yielded insights into organism feeding habits, reproduction and life histories. Sedimentological evidence presented here reveals that typical ‘Nama‐type’ Ediacaran macro‐fossils (Cloudina, Ernietta, Pteridinium and Rangea) in the Dabis and Zaris formations of the Witputz Sub‐basin seldom preserve organisms in life position in their original palaeoenvironments. Both soft‐bodied and biomineralizing organisms were transported in sediment gravity flows (debris flows, turbidity flows and transitional debris flow‐turbidity flow ‘hybrid’ event beds) or combined flow (hummocky cross‐strata) to their terminal environment of deposition in shoreface and offshore shelf settings. Transport has placed studied beds and their associated macro‐organisms in depositional settings detached from the original life habitat, with macro‐organisms sourced from shallower‐water, up‐slope environments. Integrated sedimentological and palaeontological data indicate that the Nama Group may not provide a high‐fidelity record of original Nama ecosystems. Individual macro‐organisms are clasts within beds, and can be horizontal, imbricated or chaotic in orientation. Transport can blend different communities at various scales (bed, outcrop and basin), complicating interpretations of life habitats, species interactions and taxon‐specific ecology, such as feeding behaviour and life position of organisms. Recognition of organism transport also impacts datasets used for comparing global Ediacaran fossil assemblages, with implications for tracking spatial and temporal patterns in early animal evolution.

Population structure and feeding habits of Carcinoscorpius rotundicauda in the bay environment, Southern Gulf of Thailand

This study presents the first comprehensive assessment of the population structure and feeding habits of Carcinoscorpius rotundicauda in Thailand. Sample collection was conducted using crab gill nets at seven sampling sites characterized by distinct ecosystem attributes in Pattani Bay between February 2019 and March 2020. Our findings indicate the presence of a single Asian horseshoe crab (HSC) species within the bay, with a sex ratio of approximately 1:1 (48.1 % males, 51.9 % females) that did not deviate significantly from parity. Habitat variation within the bay did not influence HSC abundance (P > 0.05) whereas monthly abundance fluctuations were highly significant (P < 0.001), peaking in March and reaching the lowest in September. Positive correlations were observed between HSC abundance and environmental factors including dissolved oxygen, temperature, water pH, water depth, and chlorophyll c concentrations. Linear regression analysis revealed a positive correlation between morphometric characteristics and body weight. However, multiple linear regression analysis indicated a negative relationship between body weight and telson length (TEL) and opisthosoma width (OW) of males, as well as TEL of females. The size at which 50 % of the HSC population reached maturity (L50) was estimated to be 12.2 cm for males and 13.5 cm for females based on prosomal width (PW). The average PW measurements of HSC at different egg stages (1–4) from developing to mature females was 14.4 cm, with corresponding body weights ranging from 224 to 243 g. Females at egg of stages 3 and 4 were found throughout the year, indicating multiple spawning events, particularly prevalent in January-April, and predominantly abundant at stations 1, 2, 5 and 6. HSC primarily consumed bivalves (22.1±21.2 %), followed by fishes (5.9±13.0 %) and crustaceans (2.9±9.0 %) by volumetric contribution (%V). This comprehensive study provides novel insights into the population dynamics and feeding ecology of HSC within Thailand. The findings establish a foundational framework for future research endeavors and offer critical data to inform the management and conservation of their habitats.

Organ-specific bioaccumulation of microplastics in market fish of Dhaka and size-dependent impacts of PVC microplastics on growth of Anabustestudineus

Microplastics (MPs), a growing environmental concern with potential ecotoxicological risks, are ubiquitous in aquatic environment. This study investigated the organ-specific distribution and variation of MPs in commercially caught fishes (7 species, 140 individuals) collected from Dhaka's two main fish distribution hubs (Uttara and Jatrabari). Additionally, the impact of different-sized MPs on fish growth (Anabas testudineus) was examined in a control experiment. Results revealed that kidneys of market fish bioaccumulated the highest concentration of MPs (average, 59.1 MPs/g), followed by liver (24.6 MPs/g) and intestine (18.6 MPs/g). On average, fish from Uttara had a higher MPs concentration (36 MPs/g) compared to Jatrabari (25 MPs/g). Among fish species, Glossogobius giuris showed the highest MPs bioaccumulation due to its feeding habits and morphology. Fiber-shaped MPs were most prevalent in all fishes (79–93%) except Glossogobius giuris (fragments, 51%). Fourier-transform infrared spectroscopy (FTIR) analysis identified 19 different polymer types, with high density polyethylene (HDPE), ethylene vinyl acetate (EVA) and polyamide (PA) being commonly found in all organs. The experimental study confirmed that large-sized PVC MPs (1.18 mm-300 μm) had a greater negative impact on fish growth (length) and caused more physical deformities (particularly intestinal injuries) compared to small-sized PVC MPs (150 μm–75 μm). Moreover, fish exposed to larger diameter MPs experienced highest physical weight and depth loss among exposed groups. Large-sized PVC MPs bioaccumulated highest in fish compared to small-sized PVC MPs. Similar to market fish, kidney in the experimental fish had the highest MPs bioaccumulation (6.5 MPs/g), followed by liver (5.2 MPs/g) and intestine (4.8 MPs/g), with a dominance of fibers despite the presence of high concentration of fragments in the food source. Statistical analysis also supported a clear correlation between increasing MPs size and adverse effects on fish growth and health. Urgent action is needed to curb microplastic pollution and protect ecosystems and human health.

The importance of livestock in the diet of Mexican wolf Canis lupus baileyi in northwestern Mexico

The reintroduction of the Mexican wolf in the wilds of northwestern Mexico has allowed us to address its trophic ecology and elucidate conflicts with livestock producers: their main mortality factor. Our objective was to determine the feeding habits of wolves in Mexico, as well as the quantity and frequency of livestock predation in relation to seasonal and individual variables, through the analysis of genetically identified scats. During 2012–2022 we collected 1171 Mexican wolf scats. We extracted and sequenced DNAm and identified individuals and their sex using microsatellite analysis. We washed the scat and separated the undigested components for taxonomic identification. We estimated the frequency of prey items, the biomass it contributed to the diet, and compared prey consumption between sexes and between the birth and dispersal seasons. We constructed generalized linear models to identify the relationship between livestock presence in the diet and dietary prey richness with respect to environmental and individual variables. We identified 68 wolves that had consumed 30 species of vertebrates. Of these, white‐tailed deer (36.12%), diversionary feeding (22.79%), and cattle (25.56%) had the highest contribution to biomass. The ingestion of items was independent of the sex of the wolves but was dependent on the season. The presence of deer and diversionary feeding decreased the likelihood of cattle being ingested but also decreased the richness of items of wild species in the wolf diet. Wolves in northwestern Mexico fed mainly on large prey available in the reintroduction area, including livestock. As wolves consume livestock, it increases the risk of retaliatory actions from ranchers. Our results serve as a basis for the implementation of strategies to reduce human–wolf conflicts and set a baseline for coexistence in northwestern Mexico.

Morphology of the Mouthparts of Ladybeetle Vibidia duodecimguttata (Coleoptera: Coccinellidae), with Emphasis on Their Sensilla

Mouthparts are the feeding organs of insects, which play vital roles in the feeding process. The morphology of insect mouthparts has greatly evolved according to different foods and feeding habits. Therefore, studying the structure of the mouthparts is the key to understanding their feeding mechanisms. Vibidia duodecimguttata is an important biological control agent for powdery fungus. In this study, the fine morphology of the mouthpart of V. duodecimguttata was studied by scanning electron microscopy. The basic components of mouthpart of V. duodecimguttata are similar to those of other ladybeetles, while the specific morphology of each part is different. In total, six kinds of sensilla were identified on mouthpart, and twelve types of sensilla were divided according to their morphology, length and distribution. In addition, two kinds of glandular structures were also found, namely perforated plates and cuticular pores. Finally, the morphological differences between mycetophagous and other feeding habits ladybeetles were compared, and the function of each kind of sensilla was discussed, which may establish a solid foundation for further understanding of the feeding mechanism of ladybirds.

Molecular Insights and Pharmacotherapy of Diabetic Neuropathy

Background: Diabetes mellitus is a chronic disorder of energy metabolism caused by lack or decrease in the effectiveness of insulin, and is characterised by an abnormally elevated blood glucose concentrations and the development of macrovascular, microvascular and/or neuropathic complications. Diabetic neuropathy (DN) is one of the most debilitating outcomes of diabetes mellitus, and may cause pain, decreased mobility as well as amputation. Diabetes can damage the peripheral nervous system (PNS), through the induction of de-myelination in neurones, precipitated by chronic hyperglycaemia-induced oxidative stress, and causing a condition that involves the upper and lower limbs. Objective: The study discussed the risk factors for insulin resistance and pre-diabetes, type II diabetes mellitus and vascular complications, cellular and molecular basis of DN, physiopathological mechanisms, and the pharmacological treatment of DN. Method: The study examined journal articles and standard textbooks, as it relates to diabetes mellitus and its complications. Search for articles on DN was carried out in the literature. These were identified and reviewed for selection using chemical abstracts service, pubmed, google scholar, crossreference, web of science, pubmed central free article, and scopus. The key words used for search were: diabetic neuropathy; diabetic peripheral neuropathy; peripheral neuropathy; microvascular complications of diabetes mellitus; and neuromuscular complications of diabetes mellitus. Result &amp; Discussion: Two hundred and fifty (250) articles and other works were identified, while ninety-seven (97) articles and non-journal materials were extracted and reviewed, taking into account the criteria for selection. Studies done in the last 4.5 decades were included, while works written on other languages, outside English were excluded. Findings indicate that DN is a complex disorder that affects the peripheral and/or cranial nerves, which is caused by unattended or poorly attended, long-term increase in blood glucose concentrations. It relatively manifests early, affecting a significant proportion of the micro-blood vessels in the middle-aged and elderly diabetic patients. DN causes numbness, loss of sensation, and sometimes pain in the feet, legs, arms or hands. Hyperglycaemia causes the activation and inhibition of several molecular pathways that are crucial for homeostasis in neuronal and neuroglial cells. Conclusion: DN is the commonest complication of diabetes mellitus. It has no known definitive therapy. Treatment is essentially symptomatic with huge economic and psychological burden, hence the rationale for a cost effective and targeted therapies. Achieving euglycaemia using anti-diabetic regimens (i.e., insulin and oral hypoglycaemic agents), foot care, changes in feeding habits and lifestyle modification are critical to holistically address the problem.

Revision of the Aspistomella group of genera (Diptera: Ulidiidae: Pterocallinae: Lipsanini)

Twenty-three species of the genera Aspistomella Hendel, 1909, Polyteloptera Hendel, 1909, and Ulivellia Speiser, 1929 occurring in South America (Colombia, Peru, Bolivia, and Brazil) form a monophyletic lineage sharing certain combinations of plesiomorphies and apomorphies with similar larval biology. The name Aspistomella Hendel, 1909 is a new senior subjective synonym of Paraphyola Hendel, 1909. The group of genera is extended by the addition of six known species, Aspistomella angustifrons (Hendel, 1909) comb. nov., A. crucifera (Hendel, 1909) comb. nov., A. lobioptera Hendel, 1909, A. heteroptera Hendel, 1909, A. lunata (Hendel, 1909) comb. nov., Polyteloptera apotropa Hendel, 1909, and Ulivellia inversa Speiser, 1929, and 17 previously unknown species. Aspistomella duo Kovac, Kameneva &amp; V. Korneyev, sp. nov., A. enderleini Kameneva &amp; V. Korneyev, sp. nov., A. garleppi Kameneva &amp; V. Korneyev, sp. nov., A. obliqua Kameneva, V. Korneyev &amp; Savaris, sp. nov., A. pachitea Kameneva &amp; V. Korneyev, sp. nov., A. quinquincisa Kameneva &amp; V. Korneyev, sp. nov., A. sachavaca Smit &amp; Kameneva, sp. nov., A. schnusei Kameneva &amp; V. Korneyev, sp. nov., A. steyskali Kameneva &amp; S. Korneyev, sp. nov., A. teresensis Araújo, V. Korneyev &amp; Savaris, sp. nov., A. tres Kovac, Kameneva &amp; V. Korneyev, sp. nov., Ulivellia amnoni Smit, sp. nov., U. arcuata Kovac &amp; Kameneva, sp. nov., U. laetitiae Smit, sp. nov., U. pseudinsolita Kameneva &amp; V. Korneyev sp. nov., and U. tenoris Kovac &amp; Kameneva sp. nov. are described. A key to the genera and species is given. Among the Lipsanini, this group of genera is easily recognised by the combination of an enlarged, anteriorly produced epistome (lower part of the face) and a low clypeus (in the other lipsanine genera the clypeus is high and the epistome is not enlarged), which supports its monophyly, and the differentiated short parafrontal setulae and long and strong frontal and interfrontal setae, which is a synapomorphy of a larger monophyletic lineage that also includes Chaetopsis Loew, 1868 and related taxa, as well as Amethysa Macquart, 1835, Euphara Loew, 1868 and their relatives. As far as is known, most species of this larger lineage are associated with various Poaceae plants. The species included here in the Aspistomella group are also associated with neotropical tall grasses: bamboo (Guadua) and wild cane (Gynerium). Aspistomella and Ulivellia larvae inhabit water-filled internode cavities (= “bamboo phytotelmata”) of living bamboo culms of Guadua angustifolia. Newly emerged larvae use tunnels made by lepidopteran borers (Crambidae caterpillars) to penetrate the hard bamboo walls. Aspistomella and Ulivellia larvae are saprophagous and adapted to an aquatic lifestyle. The last instar larvae jump easily and pupate in the soil. The external morphology, cuticular sensilla and cephalopharyngeal skeletons of the third instar larvae of five Aspistomella and Ulivellia species (one with unknown adult stage) were studied by light and scanning electron microscopy. The main features that allow the identification of larvae and puparia are the unique posterior spiracles and the structure of the abdominal creeping welts. The morphological characteristics of Aspistomella and Ulivellia larvae are compared with other Lipsanini and their feeding habits with other ulidiids. An identification key for Aspistomella and Ulivellia is given. The adaptations to life in bamboo phytotelmata found in both neotropical Aspistomella and Ulivellia and in oriental members of the closely related family Tephritidae are discussed.

Discovery of two new species of cobia (Pisces; Rachycentridae) inhabiting the makran coast of the northern Arabian Sea with notes on their biology and ecology

Cobia, Rachycentron canadum has long been regarded as the sole species in the family Rachycentridae, and has a wide distribution in tropical and sub-tropical regions of the Atlantic, Indian Ocean and western Pacific. This study describes two newly identified species, Rachycentron blochii sp. nov. and Rachycentron makranesis sp. nov. from Gwadar in the northern Arabian Sea. The newly discovered species differ significantly from their relatives in multiple morphological traits, such as head profile, mouth, pectoral fin, caudal fin, caudal peduncle, dorsal and anal fin bases, gill rakers, and body coloration. Additionally, species delimitation was further supported by examining body scales and otoliths (sagitta, lapillus, and asteriscus), with shapes also delimiting species. The recent finding increases the number of cobia species in the northern Arabian Sea, Pakistan. Moreover, details on the biological and ecological aspects such as feeding habits, age assessment, habitat preferences and fishery-related details are presented.

An Investigation on the Food and Feeding Habit of &amp;lt;i&amp;gt;Sarotherodon Galilaeus &amp;lt;/i&amp;gt;(Cichlidae) in Egbe Reservoir, Ekiti State, Nigeria

A study on the food and feeding ecology of &amp;lt;i&amp;gt;Sarotherodon galilaeus&amp;lt;/i&amp;gt;, a species of cichlid found in Nigeria&amp;apos;s Egbe Reservoir. For the investigation, 305 fish specimens were used. The stomach contents were analyzed using diet indices such as stomach fullness, numerical approach, and frequency of occurrence method. Additionally, the Geometric Index of value (GII) was used to determine the relative value of these food products. The findings showed that both adult and juvenile &amp;lt;i&amp;gt;Sarotherodon galilaeus&amp;lt;/i&amp;gt; fed on nine various food sources. The variety of food items included rotifers, algae, desmids, diatoms, protozoa, detritus, aquatic insects, aquatic plants, and insect larvae. The inclusion of detritus in the food items suggests that the fish species graze on both surface water and bottom sediments. Algae had the highest frequency of occurrence (46.39%) in both sizes and seasons, whereas rotifer had the lowest value (1.55%). Since it is possible to create the artificial diet required for this species&amp;apos; mass production in Nigeria, the findings of this study are very significant for the culture of that species&amp;lt;i&amp;gt;. Sarotherodon galilaeus&amp;lt;/i&amp;gt; can be classified as an omnivore because it consumed a variety of foods. Since feeding accounts for 60–65% of the aquaculture industry for any species being raised, research on fish diet and feeding habits is essential to developing an effective aquaculture management system. As a result, the fish species may be raised in our garden.

Gastrointestinal Conditions Affect Chronic Pain and Quality of Life in Women

Pain is a chronic condition in many women; drugs used for its treatment are often accompanied by detrimental effects on many organs, including the gut. Once inflamed, the gut can affect pain processes. The aim of this study was to evaluate the general health of women suffering chronic pain, with particular attention to gastrointestinal (GI) conditions. The possibility to improve pain and quality of life through personalized nutritional advice was also tested. Forty women suffering from chronic pain were contacted for the administration of questionnaires to define their pain features and gastrointestinal conditions. Their psychological, clinical and reproductive states were also recorded. Pain scores were correlated with GI, psychological and clinical scores. Diet suggestions were given, and evaluation was repeated after 4 weeks. Thirty-eight women were included in the study: 32 suffered chronic widespread pain and had 6 pelvic pain. Pain had been present in all women for years; more than 80% of women reported various types of disorders related to the gut. Pain scores were worse in the women intolerant to milk and dairy products. The GI score was positively correlated with the pain score. The Dietary Inflammatory Index was very high in all subjects. Personalized nutritional advice followed by 26 subjects for 4 weeks resulted in a significant improvement of pain and quality of life parameters. We describe women with chronic pain as being particularly affected by GI alterations. The change in feeding habits had a beneficial effect on pain and other quality of life parameters.

Using satellite tracking to assess the use of protected areas and alternative roosts by Whooper and Bewick's Swans

Protected areas are one of the major tools used in the conservation of biodiversity, but animals are unlikely always to remain within these human‐made boundaries. Understanding when and why species choose to leave protected areas can help us to improve the effectiveness of these management tools. Here, we investigate the use of protected and non‐protected areas by two migratory species undergoing rapid wintering population changes in northwest Europe: Whooper Swans Cygnus cygnus and Bewick's Swans Cygnus columbianus bewickii. Global positioning system tags were fitted to 15 Whooper Swans in winter 2008/09 and to 18 Bewick's Swans from winter 2013/14 to 2014/15 at the Ouse Washes Special Protection Area (an internationally important roost for wintering waterbirds) and on adjacent fields in southeast England. Here, swans feed on farmland during the day but return to designated reserves to roost at night, where they receive protection from predators and disturbance within managed roost habitats. When swans roost elsewhere at alternative sites, they may face more adverse conditions, and so understanding the extent and causes of the use of alternative roosts is important for swan conservation efforts. The alternative roosting proportion, defined as the proportion of nights spent outside protected reserves, was 0.237 for Bewick's Swans and challenging to quantify accurately for Whooper Swans. A generalized additive mixed model to model repeated measurements on individuals showed that the proportion of time that Bewick's Swans spent at alternative roosts correlated positively with river level and negatively with temperature. Competition and foraging flight distances are thought to drive these relationships, as swans seek access both to roost space and to nearby feeding habitats. Our findings improve our understanding of the environmental conditions under which migratory waterbirds may choose to roost outside protected areas.

Capybara (Hydrochoerus hydrochaeris) Salivary Glands Morphology.

Morphological studies concerning salivary glands have emerged as an exciting tool to understand feeding habits. In this sense, this study aimed to describe capybara salivary glands morphology to understand potential morphological associations to this species feeding habits. Macroscopic dissections and microscopic analyses were performed on eight specimens. The findings indicate that capybaras have three pairs of major (parotid, mandibular and sublingual) and two pairs of minors (dorsal and ventral buccal) salivary glands. The parotid gland, the largest, is irregularly shaped, forming small macroscopic lobes. The mandibular gland is rounded and found syntopically alongside the mandible angle and arranged medially to the ventral projection of the parotid gland. The sublingual gland is a compact elongated and semicircular mass. The dorsal and ventral buccal glands are located in the buccal portion of the buccinator muscle. Histologically, the parotid and mandibular glands are composed of serous acini, while the sublingual and buccal (dorsal and ventral) glands consist of mucous tubules containing serous demi-lunes at their periphery. Capybara salivary glands reveal morphological associations with a predominantly herbivorous diet. The parotid gland, for example, notably developed in size and volume, suggests a specialisation for increased saliva production, necessary for chewing, forming the food bolus, swallowing fibrous foods, and protecting the oral cavity ecosystem.

Rove beetle species diversity and the patterns of interactions with their host plants in primary and secondary tropical forests

In tropical disturbed forests, it is relatively unknown the extent insect communities are experiencing shifts in species diversity and the consequences for ecosystem functions and services. In southern Mexico, we used the rove beetle community associated to Heliconia wagneriana bracts, as a model system, to investigate differences in community attributes and feeding habits between old-growth and human induced secondary forests. We tested if the beta diversity components of rove beetle communities were influenced by forest type and bract traits. Furthermore, we described the topology of individual-based heliconia-rove beetle ecological networks. Overall, we recorded 26 rove beetle species with significantly greater abundance in secondary forests. High compositional dissimilarity between forest types was observed with saprophagous species being more likely detected in old-growth forests; whereas predatory species in secondary forests. Heliconia-rove beetle networks showed a significant nested pattern with incidence data for old-growth forests and incidence and abundance data for secondary forests. Compared to old-growth forests, the rove beetle community in secondary forests showed strong shifts in species composition, diversity and differences in the detection probability of feeding habits, with consequences for ecosystem functioning. We further discuss these findings according to the forest disturbance and phytotelm systems. Implications for insect conservation: Individuals of H. wagneriana represent biodiversity reservoirs for invertebrates, especially in human-modified landscapes.

Transcriptome analysis reveals the importance of phototransduction during the first-feeding in mandarin fish (Siniperca chuatsi).

The mandarin fish (Siniperca chuatsi), as a typical freshwater carnivorous fish, has high economic value. Mandarin fish have a peculiar feeding habit of feeding on other live fry during the first-feeding period, while rejecting zooplankton or particulate feed, which may be attributed to the low expression of zooplankton-associated gene sws1 in mandarin fish. The domesticated strain of mandarin fish could feed on Artemia at 3 days post hatching (dph). However, the mechanism of mandarin fish larvae recognize and forage Artemia as food is still unclear. In this study, we employed transcriptional analysis to identify the representative differential pathways between mandarin fish larvae unfed and fed with Artemia at 3 dph. The comparative transcriptome analysis has unveiled a tapestry of genetic expression, highlighting 403 genes that have been up-regulated and 259 that have been down-regulated, all of which constitute the differentially expressed genes (DEGs). KEGG pathway analysis revealed that the number of differentially expressed genes in the photoconductive signaling pathway was the largest. Next, the Vorinostat (suberoylanilide hydroxamic acid, SAHA) was used to assess whether sws1 induced ingestion of Artemia in mandarin fish larvae. We discovered that SAHA-treated larvae had more food intake of Artemia and up-regulated the transcription level of npy, which might have been associated with the up-regulated of sws1 opsin. Additionally, exposure to 0.5 µM SAHA increased the expression of genes involved in phototransduction pathway. These findings would provide insights on the molecular processes involved in mandarin fish larvae feeding on Artemia at the first-feeding stage.

Trophic Structure of Fish Community in Artificial Reef Ecosystem Based on Body Mass Using Stable Isotope

Artificial reefs are widely recognized for their role in improving the ecological environment and creating protected habitats for marine organisms, ultimately enhancing biodiversity within the food web and fisheries resources. This study utilizes stable isotopes to analyze fish samples ranging from 3.4 to 1067 g in body mass, collected within the artificial reef area of Haizhou Bay. The objective is to determine if the δ15N-based fish body mass acts as a driving factor in shaping the food web structure. The results showed a certain level of overlap among all trophic guilds, suggesting that most trophic guilds within this region share similar living environments and feeding habits. The multiple linear regression showed a slight increasing trend between δ15N values and body mass. Furthermore, the predator–prey mass ratio (PPMR) was calculated to be 430:1 based on the δ15N–body mass relationship. This implies that larger reef fish within this artificial reef ecosystem tend to have higher δ15N values compared to smaller fish, indicating a shorter food chain in this ecosystem. In summary, this analysis provides valuable insights into the fish community structure within artificial reef ecosystems. Therefore, it is recommended that future studies focus on further characterizing the fish community structure using body mass information.

Comparative analysis of intestinal flora community composition and diversity of Anas platyrhynchos and Anser fabalis in the Yellow River Delta

Abstract The Yellow River Delta wetland is a habitat for wintering waterfowl, where mallard (Anas platyrhynchos) and tundra bean goose (Anser fabalis) are commonly observed. Although the intestinal flora plays a pivotal role in maintaining host health and promoting nutrient absorption, it remains unclear whether the same overwintering habitat and challenging feeding conditions specifically affect the composition and diversity of intestinal flora in both species. Here, high-throughput sequencing was used to compare the intestinal bacterial communities of mallard and tundra bean goose from the same region. There was no significant difference in alpha diversity and beta diversity between the two species. Firmicutes and Proteobacteria were the two predominant phyla, accounting for more than 50.00% of the total. They enhanced the nutrient absorption and metabolic efficiency during overwintering. Catellicoccus was the most dominant genus in the intestinal flora of tundra bean goose, accounting for 33.91%, whereas Clostridium sensu stricto 1 was the most dominant genus in mallard, accounting for 7.34%. This difference is considered to be related to the feeding habits of these two species. No significant differences in the structure and diversity of intestinal bacterial communities were observed between mallard and tundra bean goose, and the similarity of intestinal flora between them was high. This study deepens our understanding of the intestinal flora of two coexisting species with different dietary preferences in the Yellow River Delta. It also lays the foundation for waterfowl disease prevention in this area, carrying significant scientific and practical implications for biodiversity and ecosystem conservation.