Waterfowl Breeding Research Articles

Uncovering habitat associations and thresholds—insights for managing breeding waterfowl in Eastern Canada

ContextUnderstanding how habitat influences species abundance is crucial in developing ecologically sound wildlife conservation management plans. Exploring habitat associations and ecological thresholds in species’ responses allows for better conservation and management on a landscape-scale.ObjectivesThis work aimed to identify habitat drivers and response thresholds of waterfowl and waterbird species’ densities in eastern Canada to support key landscape-level decisions for habitat conservation and wetland management.MethodsWe developed predictive abundance models for 17 species across eastern Canada from 2001 to 2015 using data from four regional surveys and identified areas where prioritizing enhancement of wetlands would increase the breeding density of five priority waterfowl species.ResultsHabitat associations and spatial abundance patterns varied across species, but most species responded strongly to forest composition, agriculture, and wetland features. Threshold effects occurred and varied among species, yet generally once 14% of a plot was covered in wetlands, positive effects of increased wetland diminished for most species. Our results allow for the targeting of investments in increasing wetland area along portions of eastern Canada that provide the best opportunities to increase breeding densities for priority waterfowl species.ConclusionsUnderstanding species-habitat associations and response thresholds allows for landscape management and planning and prioritization of limited resources. We suggest that management and wetland enhancement efforts for waterfowl in eastern Canada should be guided by predictive models and response thresholds of key habitat attributes to best prioritize actions that will have the biggest positive impact on multiple species.

Genome cloning and genetic evolution analysis of eight duck-sourced novel goose parvovirus strains in China in 2023.

There are three major categories of waterfowl parvoviruses, namely goose parvovirus (GPV), Muscovy duck parvovirus, and novel goose parvovirus (NGPV). NGPV can infect both Cherry Valley ducks and mule ducks, resulting in short beaks and dwarfism syndrome, and the incidence of short beaks and dwarfism syndrome rises annually, posing a significant threat to the waterfowl breeding and the animal husbandry. Therefore, clarifying the biological characteristics and genetic evolution of NGPV is very important for the prevention and control of NGPV. Ducks with short beaks and dwarfism syndrome from Shandong and Henan Province were investigated by dissection and the tissue samples were collected for study. The NGPV genome was amplified by PCR, and the genome was analyzed for genetic evolution. Eight strains of NGPV were isolated, which were designated as HZ0512, HZ0527, HZ0714, HZ0723, HZ0726, HZ0811, HZ0815, and HN0403. The nucleotide homology among these strains ranged from 99.9% to 100%. The eight strains, along with other NGPVs, belong to GPV. The eight strains showed a 92.5%-98.9% nucleotide homology with the classical GPV, while a 96.0%-99.9% homology with NGPV.Therefore, it can be deduced that there have been no major mutations of NGPV in Shandong and Henan provinces in recent years. This study lays a theoretical foundation for further studying the genetic evolution and pathogenicity of NGPV, thereby facilitating the prevention and control of NGPV.

Integrative and Conjugative Elements and Prophage DNA as Carriers of Resistance Genes in Erysipelothrix rhusiopathiae Strains from Domestic Geese in Poland.

Goose erysipelas is a serious problem in waterfowl breeding in Poland. However, knowledge of the characteristics of Erysipelothrix rhusiopathiae strains causing this disease is limited. In this study, the antimicrobial susceptibility and serotypes of four E. rhusiopathiae strains from domestic geese were determined, and their whole-genome sequences (WGSs) were analyzed to detect resistance genes, integrative and conjugative elements (ICEs), and prophage DNA. Sequence type and the presence of resistance genes and transposons were compared with 363 publicly available E. rhusiopathiae strains, as well as 13 strains of other Erysipelothrix species. Four strains tested represented serotypes 2 and 5 and the MLST groups ST 4, 32, 242, and 243. Their assembled circular genomes ranged from 1.8 to 1.9 kb with a GC content of 36-37%; a small plasmid was detected in strain 1023. Strains 1023 and 267 were multidrug-resistant. The resistance genes detected in the genome of strain 1023 were erm47, tetM, and lsaE-lnuB-ant(6)-Ia-spw cluster, while strain 267 contained the tetM and ermB genes. Mutations in the gyrA gene were detected in both strains. The tetM gene was embedded in a Tn916-like transposon, which in strain 1023, together with the other resistance genes, was located on a large integrative and conjugative-like element of 130 kb designated as ICEEr1023. A minor integrative element of 74 kb was identified in strain 1012 (ICEEr1012). This work contributes to knowledge about the characteristics of E. rhusiopathiae bacteria and, for the first time, reveals the occurrence of erm47 and ermB resistance genes in strains of this species. Phage infection appears to be responsible for the introduction of the ermB gene into the genome of strain 267, while ICEs most likely play a key role in the spread of the other resistance genes identified in E. rhusiopathiae.

The influence of landscape composition and configuration on breeding waterfowl pair abundance in Wisconsin

AbstractHabitat loss and fragmentation have negatively impacted breeding birds across the world. Across guilds, grassland‐dependent birds have experienced the largest proportional loss of their breeding population while wetland‐dependent birds have realized overall net gains in part due to focused conservation efforts. However, some species within the wetland‐dependent guild have a strong dependence on non‐wetland land cover types during the annual cycle and therefore may be equally sensitive to reductions in the composition and altered configuration of upland landcover, such as grasslands. We explored the influence of landcover composition and configuration on the number of breeding pairs of a breeding habitat generalist, the mallard (Anas platyrhynchos), and a grassland‐dependent breeding species, the blue‐winged teal (Spatula discors), in agriculturally‐intensive landscapes of Wisconsin, USA. Because of the extensive landscape alteration and habitat fragmentation that has occurred, we expected mallards to have a more utilitarian response to varying landscape composition compared to a grassland nesting obligate like blue‐winged teal. We used helicopter surveys conducted across 8 years (2001–2003, 2006–2009, and 2012) and remotely‐sensed land cover data to investigate the influence of habitat associations on relative abundance of breeding pairs. Model selection indicated that landscape composition models outperformed landscape configuration and null models for both species. Consistent with our predictions, we found that mallard pair counts were positively influenced by a greater number of land cover covariates compared to blue‐winged teal. Both blue‐winged teal and mallard breeding pairs were positively related to increased composition of emergent and scrub‐shrub wetlands as well as upland grassland. Additionally, we found that mallard pairs were positively related to forested, cattail (Typha sp.), and open water wetland types, whereas predicted blue‐winged teal pair abundance was negatively related to forested wetlands and had a nonlinear relationship and declined when surveyed land sections were comprised of more than 30% cattail‐dominated wetlands and 20% open‐water wetlands. Increased quantities of cattail‐dominated and open‐water wetland cover types comparatively provide less habitat for blue‐winged teal and may reflect broader shifts in habitat composition that have likely resulted from agricultural intensification and stabilized hydrology. Conservation activities that preserve existing nesting land cover types or restore hydrologically‐dynamic emergent wetlands in proximity to upland grassland cover could mutually benefit both species.

Evaluation of breeding distribution and chronology of North American scoters

North America's scoter species are poorly monitored relative to other waterfowl. Black Melanitta americana, surf M. perspicillata, and white‐winged M. deglandi scoter abundance and trend estimates are thus uncertain in many parts of these species' ranges. The most extensive source of waterfowl abundance and distribution data in North America is the Waterfowl breeding population and habitat survey (WBPHS). Although the WBPHS effectively monitors most species, both its timing and geographic coverage may preclude accurate scoter monitoring. Therefore, our goal was to better define when and where scoters breed to help interpret survey results and optimize potential supplemental survey efforts for scoters. We integrated satellite telemetry tracking data from scoters marked at multiple molting, staging, breeding, and wintering areas along the Atlantic and Pacific coasts to quantify continent‐wide breeding chronology and distribution. We also examined possible drivers of variation in timing of arrival, length of stay, and departure at nesting locations. We documented a northwest to southeast distribution of estimated breeding sites across Alaska and Canada. On average, scoters arrived at nest sites on 1 June. Surf scoters and Pacific black scoters arrived earliest and departed earliest. Pacific‐wintering black and white‐winged scoters began breeding earlier than Atlantic‐wintering birds. Additionally, birds arrived at nesting locations earlier in years with earlier snowmelt, and later snowmelt reduced lengths of stay for males. Breeding chronology also varied by age group, with adults arriving earlier than subadults. Our study is the first to comprehensively describe spatial variation in timing of breeding of both Atlantic and Pacific populations of all three scoter species across North America. Our results increase our understanding of how current surveys enumerate scoters and will inform possible supplemental efforts to improve continental monitoring of scoter populations.

A meta-analysis for vaccine protection rate of duck hepatitis a virus in mainland China in 2009–2021

BackgroundDuck hepatitis A virus (DHAV) is a single-stranded, positive-strand small RNA virus that causes a very high mortality rate in ducklings. The DHAV-3 subtype incidence rate has recently increased in China, causing great economic losses to the waterfowl breeding industry. We analyzed the protection rate of DHAV vaccines used in mainland China from 2009 to 2021 and evaluated the effectiveness of vaccine prevention and control to reduce the economic losses caused by DHAV to the waterfowl breeding industry. We screened five electronic research databases and obtained 14 studies and patents on the protection efficiency of DHAV-1 and DHAV-3 vaccines.ResultsMeta-analysis demonstrated that immunized ducklings produced higher antibody levels and had a significantly higher survival rate than non-immunized ducklings [relative risk (RR) = 12, 95% confidence interval (CI) 6–26, P < 0.01]. The age of the ducks and vaccine valence did not affect protection efficiency. Data source analysis of the vaccine protection rate demonstrated that the vaccines conferred immune protection for ducklings in both small-scale experiments and large-scale clinical conditions. The analysis results revealed that although the vaccines conferred protection, the immune protective effect differed between small-scale experimental conditions and large-scale clinical conditions. This might have been due to non-standard vaccination and environmental factors.ConclusionsDomestic DHAV vaccines can protect ducklings effectively. The subjects immunized (breeding ducks or ducklings) and vaccine valence had no effect on the protective effect. Both small-scale experiments and large-scale clinical conditions conferred immune protection on ducklings, but vaccine immunization under small-scale experimental conditions had slightly better protective effects than large-scale clinical immunization.

Pre- and Post-Impoundment Study of Breeding Waterfowl Use of a Hydroelectric Reservoir in the Eastern Canadian Boreal Forest

Pre- and Post-Impoundment Study of Breeding Waterfowl Use of a Hydroelectric Reservoir in the Eastern Canadian Boreal Forest

High rate of multidrug resistance and integrons in Escherichia coli isolates from diseased ducks in select regions of China

With the increasing number of ducks being raised and consumed, it is crucial to monitor the presence of multidrug resistant (MDR) bacteria in duck farming. Waterfowl, such as ducks, can contribute to the rapid dissemination of antibiotic resistance genes (ARGs). The objective of this study was to investigate the antimicrobial resistance (AMR), ARGs, and mobile genetic elements (MGEs), such as IS26, tbrC, ISEcp1 in Escherichia coli(E. coli) isolated from the intestinal contents of diseased ducks between 2021 and 2022 in Sichuan, Chongqing and Anhui, China. The AMR phenotypes of 201 isolated E. coli strains were determined using the minimum inhibitory concentrations (MICs) method. Subsequently, polymerase chain reaction and sequencing techniques were employed to screen for integron-integrase genes (intI1, intI2, intI3 genes), gene cassettes (GCs), MGEs, and ARGs. The results demonstrated that 96.5% of the E. coli isolates were resistant to at least 1 antibiotic, with 88.1% of the strains displaying MDR phenotype. The highest AMR phenotype observed was for trimethoprim-sulfamethoxazole (88.1%). Furthermore, class 1 and class 2 integrons were detected in 68.2% and 3.0% of all the isolates, respectively, whereas no class 3 integrons were found. Ten types of GCs were identified in the variable regions of class 1 and class 2 integrons. Moreover, 10 MGEs were observed in 46 combinations, with IS26 exhibiting the highest detection rate (89.6%). Among the 22 types of ARGs, tetA (77.1%) was the most frequently detected. In the conjugational transfer experiment, transconjugants were found to carry specific ARGs and MGEs, with their MIC values were significantly higher than those of recipient E. coli J53, indicating their status as MDR bacteria. This study emphasizes the necessity of monitoring MGEs, ARGs, and integrons in duck farms. It provides valuable insights into the complex formation mechanisms of AMR and may aid in preventing and controlling the spread of MDR bacteria in waterfowl breeding farm.

Waterfowl distribution and productivity in the Prairie Pothole Region of Canada: tools for conservation planning

AbstractSpecies conservation requires an understanding of the factors and interactions affecting species distribution and behavior, habitat availability and use, and corresponding vital rates at multiple temporal and spatial scales. Opportunities to investigate these relationships across broad geographic regions are rare. We combined long‐term waterfowl population surveys, and studies of habitat use and breeding success, to develop models that identify and incorporate these interactions for upland‐nesting waterfowl in the Prairie Pothole Region (PPR) of Canada. Specifically, we used data from the annual Waterfowl Breeding Population and Habitat Survey (1961–2009) at the survey segment level and associated habitat covariates to model and map the long‐term average duck density across the Canadian PPR. We analyzed nest location and fate data from approximately 25,000 duck nests found during 3 multi‐year nesting studies (1994–2011) to model factors associated with nest survival and habitat selection through the nesting season for the 5 most common upland nesting duck species: mallard (Anas platyrhynchos), gadwall (Mareca strepera), blue‐winged teal (Spatula discors), northern shoveler (Spatula clypeata), and northern pintail (Anas acuta). Duck density was highly variable across the Canadian PPR, reflecting positive responses to local wetland area and count, and amounts of cropland and grassland, a regional positive response to latitude, and a negative response to local amounts of tree cover. Nest survival was affected by temporal and spatial variables at multiple scales. Specifically, nest survival demonstrated interactive effects among species, nest initiation date, and nesting cover type and was influenced by relative annual wetness, population density, and surrounding landscape composition at landscape scales, and broad geographic gradients (east‐west and north‐south). Likewise, species‐specific probability of nest habitat selection was influenced by timing of nest initiation, population density, relative annual wetness, herbaceous cover, and tree cover in the surrounding landscape, and location within the Canadian PPR. We combined these models, with estimates of breeding effort (nesting, renesting, and nest attempts) from existing literature, in a stochastic conservation planning model that estimates nest distribution and success given spatiotemporal variation in duck density, habitat availability, and influential covariates. We demonstrate the use of this model by examining various conservation planning scenarios. These models allow estimation of local, landscape, and regional influence of conservation investments and other landscape changes on the productivity of breeding duck populations across the PPR of Canada. These models lay the groundwork for the incorporation of conservation delivery costs for full return‐on‐investment analyses and scenario analyses of climate, habitat, and land use change in regional and continental population models.

Integrating dynamic processes into waterfowl conservation prioritization tools

Diversity and DistributionsEarly View CORRIGENDUMOpen Access Integrating dynamic processes into waterfowl conservation prioritization tools This article corrects the following: Integrating dynamic processes into waterfowl conservation prioritization tools Kaylan M. Kemink, Vanessa M. Adams, Robert L. Pressey, Gwen Iacona, Volume 27Issue 4Diversity and Distributions pages: 585-601 First Published online: December 30, 2020 First published: 22 March 2023 https://doi.org/10.1111/ddi.13691AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat In the version of this paper originally published (Kemink et al., 2021), the authors would like to acknowledge a wording error which was included throughout the published paper. The authors referred to the spatiotemporal modelled predictions as ‘pair abundance models’, calculated using the equation: VIF (P + LM), when in actuality the authors modelled waterfowl breeding population VIF ((2P + 2LM) + G) where G represents mixed sex groups of waterfowl. This is largely a scaling error as the input values resulting from those two equations are correlated (correlation = 0.99). All of the resulting proportions and conclusions can remain the same. The modelling processes that the authors have rerun thus far have indicated identical model selection, correlations, etc. The authors would also like to acknowledge that some minor changes have also been made to some of the table and figure legends in the supporting information file which can be accessed as part of the online article publication. REFERENCE Kemink, K. M., Adams, V. M., & Pressey, R. L. (2021). Integrating dynamic processes into waterfowl conservation prioritization tools. Diversity and Distributions, 27, 585– 601. https://doi.org/10.1111/ddi.13218 Early ViewOnline Version of Record before inclusion in an issue ReferencesRelatedInformation

LPS-Induced Liver Injury of Magang Geese through Toll-like Receptor and MAPK Signaling Pathway.

Lipopolysaccharide (LPS) is one of the main virulence factors of Gram-negative bacteria. In the process of waterfowl breeding, an inflammatory reaction due to LPS infection is easily produced, which leads to a decline in waterfowl performance. The liver plays a vital role in the immune response and the removal of toxic components. Therefore, it is necessary to study the mechanism of liver injury induced by LPS in goose. In this study, a total of 100 1-day-old goslings were randomly divided into a control group and LPS group after 3 days of pre-feeding. On days 21, 23, and 25 of the formal experiment, the control group was intraperitoneally injected with 0.5 mL normal saline, and the LPS group was intraperitoneally injected with LPS 2 mg/(kg body weight) once a day. On day 25 of the experiment, liver samples were collected 3 h after the injection of saline and LPS. The results of histopathology and biochemical indexes showed that the livers of the LPS group had liver morphological structure destruction and inflammatory cell infiltration, and the levels of ALT and AST were increased. Next, RNA sequencing analysis was used to determine the abundances and characteristics of the transcripts, as well as the associated somatic mutations and alternative splicing. We screened 727 differentially expressed genes (DEGs) with p < 0.05 and |log2(Fold Change)| ≥ 1, as the thresholds; GO and KEGG enrichment analysis showed that LPS-induced liver injury may be involved in the Toll-like receptor signaling pathway, MAPK signaling pathway, NOD-like receptor signaling pathway, FoxO, and PPAR signaling pathway. Finally, we intersected the genes enriched in the key pathway of LPS-induced liver injury with the top 50 key genes in protein−protein interaction networks to obtain 28 more critical genes. Among them, 17 genes were enriched in Toll-like signaling pathway and MAPK signaling pathway. Therefore, these results suggest that LPS-induced liver injury in geese may be the result of the joint action of Toll-like receptor, MAPK, NOD-like receptor, FoxO, and PPAR signaling pathway. Among them, the TLR7-mediated MAPK signaling pathway plays a major role.

Persistence of low pathogenic avian influenza virus in artificial streams mimicking natural conditions of waterfowl habitats in the Mediterranean climate

Avian influenza viruses (AIVs) can affect wildlife, poultry, and humans, so a One Health perspective is needed to optimize mitigation strategies. Migratory waterfowl globally spread AIVs over long distances. Therefore, the study of AIV persistence in waterfowl staging and breeding areas is key to understanding their transmission dynamics and optimizing management strategies. Here, we used artificial streams mimicking natural conditions of waterfowl habitats in the Mediterranean climate (day/night cycles of photosynthetic active radiation and temperature, low water velocity, and similar microbiome to lowland rivers and stagnant water bodies) and then manipulated temperature and sediment presence (i.e., 10–13 °C vs. 16–18 °C, and presence vs. absence of sediments). An H1N1 low pathogenic AIV (LPAIV) strain was spiked in the streams, and water and sediment samples were collected at different time points until 14 days post-spike to quantify viral RNA and detect infectious particles. Viral RNA was detected until the end of the experiment in both water and sediment samples. In water samples, we observed a significant combined effect of temperature and sediments in viral decay, with higher viral genome loads in colder streams without sediments. In sediment samples, we didn't observe any significant effect of temperature. In contrast to prior laboratory-controlled studies that detect longer persistence times, infectious H1N1 LPAIV was isolated in water samples till 2 days post-spike, and none beyond. Infectious H1N1 LPAIV wasn't isolated from any sediment sample. Our results suggest that slow flowing freshwater surface waters may provide conditions facilitating bird-to-bird transmission for a short period when water temperature are between 10 and 18 °C, though persistence for extended periods (e.g., weeks or months) may be less likely. We hypothesize that experiments simulating real environments, like the one described here, provide a more realistic approach for assessing environmental persistence of AIVs.

Postbreeding movements and molting ecology of female gadwalls and mallards

AbstractThe wing molt is an important annual life‐history event that occurs in waterfowl and molt site selection can play an important role in determining survival. We tracked postbreeding movements of gadwall (Mareca strepera) and mallard (Anas platyrhynchos) females that bred in the Suisun Marsh (Suisun) of California, USA, to determine molt site selection and wing molt chronology. We attached backpack transmitters with global positioning system and global system for mobile communications (GPS‐GSM) technology to female gadwalls and mallards within Suisun and tracked the birds following the breeding season during 2015–2018. We determined molt locations for 52 female gadwalls and 112 female mallards. Thirty of the marked gadwall females selected 2 regions within southern Oregon‐northeastern California (SONEC) to undergo molt; 16 molted in the Upper Klamath Basin (southern OR) and 14 in the Lower Klamath Basin (northeastern CA). A large portion of female mallards molted in Suisun (n = 34) and the Sacramento Valley in California (n = 31) but also used the Upper Klamath Basin (n = 13), Lower Klamath Basin (n = 12), and the Yolo–Delta region in California (n = 12). On average, gadwalls departed Suisun on 30 July (±17.82 days [SD]), and mallards departed on 24 July (±22.69 days). Mean start date of molt for each species was similar: 27 August (±16.09 days) for gadwalls and 26 August (±21.03 days) for mallards. Molt end date was analogous for each species as well. Molt ended on average 1 October (±15.52 days) for gadwalls and on 5 October (±18.34 days) for mallards. Gadwalls and mallards showed intraspecific differences in average molt start and end date within the 3 main geographical zones: Suisun, Central Valley of California (Central Valley), and SONEC. Mean duration of wing molt for gadwalls was 34.72± 8.62 days and 41.09 ± 12.54 days for mallards. Both species primarily selected permanent marsh to undergo wing molt (gadwalls = 90.4%, mallards = 63.4%). Conservation and active management of these high‐use molting areas used by California's primary breeding waterfowl species could enhance postbreeding survival, leading to increased breeding waterfowl populations.

Predator movements in relation to habitat features reveal vulnerability of duck nests to predation.

Nest predation is the main cause of nest failure for ducks. Understanding how habitat features influence predator movements may facilitate management of upland and wetland breeding habitats that reduces predator encounter rates with duck nests and increases nest survival rates. For 1618 duck nests, nest survival increased with distance to phragmites (Phragmites australis), shrubs, telephone poles, human structures, and canals, but not for four other habitat features. Using GPS collars, we tracked 25 raccoons (Procyon lotor) and 16 striped skunks (Mephitis mephitis) over 4 years during waterfowl breeding and found marked differences in how these predators were located relative to specific habitat features; moreover, the probability of duck nests being encountered by predators differed by species. Specifically, proximity to canals, wetlands, trees, levees/roads, human structures, shrubs, and telephone poles increased the likelihood of a nest being encountered by collared raccoons. For collared skunks, nests were more likely to be encountered if they were closer to canals, trees, and shrubs, and farther from wetlands and human structures. Most predator encounters with duck nests were attributable to a few individuals; 29.2% of raccoons and 38.5% of skunks were responsible for 95.6% of total nest encounters. During the central span of duck nesting (April 17–June 14: 58 nights), these seven raccoons and five skunks encountered >1 nest on 50.8 ± 29.2% (mean ± SD) and 41.5 ± 28.3% of nights, respectively, and of those nights individual raccoons and skunks averaged 2.60 ± 1.28 and 2.50 ± 1.09 nest encounters/night, respectively. For collared predators that encountered >1 nest, a higher proportion of nests encountered by skunks had evidence of predation (51.9 ± 26.6%) compared to nests encountered by raccoons (22.3 ± 17.1%). Because duck eggs were most likely consumed as raccoons and skunks opportunistically discovered nests, managing the habitat features those predators most strongly associated with could potentially reduce rates of egg predation.

Waterfowl breeding environment humidity prediction based on the SRU-based sequence to sequence model

Good humidity control is helpful to prevent the occurrence of waterfowl diseases, so it is necessary to predict and control the humidity in waterfowl houses. Traditional sequence methods such as RNN, LSTM, and GRU face challenges in prediction accuracy and parallel performance for long sequence prediction. In this study, a novel neural network model called SRU–SRU-dense is proposed to predict the waterfowl indoor humidity for the next 6 h. Simple recurrent unit(SRU) has better parallel performance compared with LSTM and GRU, which can effectively reduce the inference time. The proposed SRU–SRU-dense model is a seq2seq model based on SRU, and the experimental results show that this model has faster prediction speed and more accurate shorter prediction accuracy than seq2seq models based on RNN, LSTM, and GRU. In addition, we also compared the performance of two different seq2seq structures, seq2seq-dense and seq2seq-sequence, and the experimental results show that the seq2seq-dense structure has faster prediction speed and better prediction accuracy in the prediction of waterfowl indoor humidity in the next 6 h.

Epidemiological survey of avian adenovirus in China from 2015 to 2021 and the genetic variability of highly pathogenic Fadv-4 isolates.

The prevalence of poultry adenovirus in China is determined using clinical diagnosis, molecular biological testing, serological testing, and LMH cell virus isolation. These methods can track and test key poultry and waterfowl breeding areas across the country. From 2015 to 2021, 9613 suspected adenovirus samples were collected from 28 provinces. After the first generation of gene sequencing, a total of 2210 hexo gene fragments were obtained. Among them, FAdV-1 type accounted for 7.65%, FAdV-2 type accounted for 5.34%, FAdV-3 type accounted for 2.04%, FAdV-4 type accounted for 38.24%, FAdV-5 type accounted for 2.17%, FAdV-6 type accounted for 0.32%, FAdV-7 type accounted for 0.77%, FAdV-8a type accounted for 10.63%, FAdV-8b type accounted for 11.58%, FAdV-9 type accounted for 0.50%, FAdV-10 type accounted for 8.10%, and FAdV-11 type accounted for 12.67%. A total of 877 FAdV strains were isolated from FAdV suspected samples by seeding LMH cells, and there were 475 FAdV-4 strains among them. A total of 473 isolates were highly pathogenic FAdV-4, and the percentage of amino acid homology with the highly pathogenic FAdV-4 reference strains was >99.1%. Two isolates were non-pathogenic, and the amino acid homology with the ON1 reference strain was >99.6%. Part of the amino acid positions of the hexon gene have mutations, including positions 188, 193, 195, 238, and 240.

Duck Plague Virus pUL48 Protein Activates the Immediate-Early Gene to Initiate the Transcription of the Virus Gene

Duck plague caused by the duck plague virus (DPV) is an infectious disease that seriously harms the waterfowl breeding industry. The VP16 protein of α herpesvirus can bind to specific cis-acting elements upstream of the promoter of the immediate-early (IE, α) gene to promote the transcription of the IE gene, so it is also called the trans-inducer of IE gene (α-TIF). However, no studies on DPV α-TIF have been reported. This study investigated the DPV pUL48, a homolog of HSV-1 VP16, transcriptional activation region, target sequence, and viral protein affecting its transcriptional activation using a dual-luciferase reporter gene detection system, and pUL48 was identified as the α-TIF of DPV. (1) The regulation of pUL48 on DPV different gene promoters showed that pUL48 could activate all the promoters of IE genes (ICP4, ICP22, and ICP27) but not the promoters of early and late genes. (2) The activity of pUL48 to ICP4 and ICP22 promoters with different upstream lengths showed that pUL48 activated ICP4 and ICP22 promoters by acting on TAATGA (T) TAT element upstream of ICP4 promoter and TAATTATAT element upstream of ICP22 promoter, respectively. (3) Transcriptional activation of IE gene by truncated proteins of different lengths at the N-terminal of pUL48 was detected. The results showed that the transcriptional activation domain of pUL48 was amino acids 1–60 at the N-terminal, and amino acids 1–20 was its core region. In addition, it was found that pUL14, pUL46, and pUL47 significantly promoted the transcriptional activation of pUL48. The effects of loss of pUL47 and its nuclear localization signal on the nuclear entry and transcriptional activation function of pUL48 were further examined. The results showed that pUL47 could promote the nuclear entry of pUL48 through its nuclear localization signal at positions 40–50 and 768–777 amino acids, thus, enhancing the transcriptional activation function of pUL48 and synergistic promotion of viral gene transcription.

Integrated modeling of waterfowl distribution in western Canada using aerial survey and citizen science (eBird) data

AbstractAlthough the exceptional spatiotemporal extent of the Waterfowl Breeding Population and Habitat Survey (WBPHS) has substantially contributed to our understanding of the ecology of North American waterfowl, vast geographical areas remain excluded from the survey. The unprecedented number of observations generated by the recent boom in citizen science initiatives could help resolve these spatial gaps and increase the density of records in regions already covered. The study objective was to assess the value of the integrated species distribution modeling (ISDM) approach for integrating WBPHS and eBird data to model waterfowl distribution across the Canadian western boreal forest, where WBPHS data are sparse. Following the ISDM approach, we used a state‐space point process formulation that combined a model for the “true” species distribution and two observation models for how WBPHS and eBird data were generated. Our results highlighted the importance of observational processes related to sampling effort and site accessibility for modeling eBird data. In addition, our models allowed identifying waterfowl–habitat associations related to geoclimatic, forest, and hydrological factors that explained the distribution of target species. To assess the individual contribution of WBPHS and eBird data, we re‐fitted the models using only one of the two data sets and compared the results obtained against those from the integrated approach. Waterfowl–habitat associations and predictions derived from the models using both data sets and those fitted with WBPHS data only were close and consistent with the observed species distribution. However, it was more difficult to extract an ecological signal from models fitted with eBird data only. Interestingly, predictions from models combining both data sets were closer to the WBPHS records than the predictions from models fitted with WBPHS data only. By facilitating the combination of all available data sources, we demonstrated the potential of the ISDM approach for modeling and mapping species distributions. We encourage future North American waterfowl modeling attempts to use this method, especially for resolving gaps in the WBPHS coverage. As multiple data sets can be added to the original framework, integration efforts must not be restricted to the additional contribution of eBird data alone and could consider, for example, provincial atlases and regional helicopter surveys.

Behavior of Smallholder to Improve Individual Breeding Environment and Tobacco Growing Environment-A Case Study of 184 Waterfowl Farmers and Tobacco Farmers in Jiangxi Province

Under the background of the structural reform on the agricultural supply side and the tightening of environmental protection policies, China’s agricultural industry is facing prominent problems such as low scale, poor mechanization level and serious ecological environment pollution, especially the scattered breeding behavior of small farmers in waterfowl breeding industry and in tobacco growing industry, which has a serious impact on the surrounding ecological environment. In this paper, based on the survey data of 184 waterfowl farmers and tobacco farmers in Jiangxi province and from the perspective of small farmers of waterfowl breeding and tobacco growing, the factors influencing small farmers’ behavior of improving their individual breeding environment and carrying out green ecological behavior are analyzed by using binary logistic regression model. It is concluded that the gender and age of farmers have a negative impact, while farmers’ education level, farmers’ concurrent employment, breeding technology training and government support have a significant positive impact on small farmers’ behavior of improving their individual breeding and planting environment. Finally, some suggestions are put forward, such as optimizing the production layout of waterfowl industry, improve green tobacco cultivation, constructing green ecological development system of waterfowl industry, popularizing green ecological breeding mode and strengthening policy support and supervision, with a view to improve the present situation of poor breeding environment and serious pollution of small farmers in China, promote the development and transformation of waterfowl industry and tobacco industry in China, and promote the sustainable development of ecological environment and ecological economy of waterfowl industry and tobacco industry in China.

Wetland Availability and Salinity Concentrations for Breeding Waterfowl in Suisun Marsh, California

Availability of wetlands with low salinities during the breeding season can influence waterfowl reproductive success and population recruitment. Salinities as low as 2 ppt (3.6 mScm–1) can impair duckling growth and influence behavior, with mortality occurring above 9 ppt (14.8 mScm–1). We used satellite imagery to quantify the amount of available water, and sampled surface water salinity at Grizzly Island, in the brackish Suisun Marsh, at three time-periods during waterfowl breeding (April, May, July) over 4 years (2016–2019). More water was available and salinity was lower during wetter years (2017, 2019) than during drier years (2016, 2018), and the amount of water in wetlands decreased 73%–86% from April to July. Across all time-periods and years, the majority (64%–100%) of wetland habitat area had salinities above what has been shown to negatively affect ducklings (&gt; 2 ppt), and up to 42% of wetland area had salinities associated with duckling mortality (&gt; 9 ppt). During peak duckling production in May, 81%–95% of available water had salinity above 2 ppt, and 5%–21% was above 9 ppt. In May of the driest year (2016), only 0.5 km2 of low-salinity water (&lt; 2 ppt) was available to ducklings in the study area, compared to 2.6 km2 in May of the wettest year (2017). Private duck clubs own the majority of wetland habitat at Grizzly Island and consistently had a greater percentage of land flooded during summer than did publicly owned wetlands, but private wetlands generally had higher salinities than public wetlands, likely because they draw from higher-salinity water sources. By July, few wetlands remained flooded, and most had salinities high enough to impair duckling growth and survival. Local waterfowl populations would benefit from management practices that provide fresher water during peak duckling production in May and retain more water through July.