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1.
PLoS One ; 16(7): e0254179, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34297737

RESUMO

Environmental quality is a major factor that directly impacts waterfowl productivity. Accurate prediction of pollution index (PI) is the key to improving environmental management and pollution control. This study applied a new neural network model called temporal convolutional network and a denoising algorithm called wavelet transform (WT) for predicting future 12-, 24-, and 48-hour PI values at a waterfowl farm in Shanwei, China. The temporal convoluted network (TCN) model performance was compared with that of recurrent architectures with the same capacity, long-short time memory neural network (LSTM), and gated recurrent unit (GRU). Denoised environmental data, including ammonia, temperature, relative humidity, carbon dioxide (CO2), and total suspended particles (TSP), were used to construct the forecasting model. The simulation results showed that the TCN model in general produced a more precise PI prediction and provided the highest prediction accuracy for all phases (MAE = 0.0842, 0.0859, and 0.1115; RMSE = 0.0154, 0.0167, and 0.0273; R2 = 0.9789, 0.9791, and 0.9635). The PI assessment prediction model based on TCN exhibited the best prediction accuracy and general performance compared with other parallel forecasting models and is a suitable and useful tool for predicting PI in waterfowl farms.


Assuntos
Poluição Ambiental/estatística & dados numéricos , Fazendas/tendências , Gansos/fisiologia , Amônia/toxicidade , Animais , Dióxido de Carbono/toxicidade , China , Poluentes Ambientais/toxicidade , Poluição Ambiental/efeitos adversos , Temperatura Alta , Umidade , Modelos Estatísticos , Material Particulado/toxicidade , Análise de Ondaletas
2.
Sci Rep ; 9(1): 12839, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492937

RESUMO

Living in groups has various advantages and disadvantages for group members. We investigated the fitness consequences of early social connectivity (normalized Freeman degrees based on nearest neighbour data), physiology (levels of excreted corticosterone metabolites assayed from droppings), and agonistic interactions in a group of free-ranging greylag geese (Anser anser). Forty-four greylag geese below 3 years of age were observed in three different seasonal phases: during the re-aggregation of the flock in autumn, at the end of the winter and during the forthcoming breeding season. We show that corticosterone metabolite levels and initiated and received aggression increased with increasing social connectivity. Individuals had higher connectivity scores in the winter flock than during the mating and breeding seasons. One-year old juveniles were more connected than 2- and 3-year old individuals. In addition, we examined the link between social connectivity during early development and reproductive success several years later. We found that birds with greater connectivity early in life attempted to breed at a younger age. Furthermore, successful breeders with higher early connectivity scores had higher numbers of fledged goslings. Our results show that social context in early life stages may have long-term effects on individual fitness.


Assuntos
Comportamento Animal/fisiologia , Gansos/fisiologia , Comportamento Social , Animais , Cruzamento , Corticosterona/metabolismo , Modelos Logísticos , Metaboloma , Análise de Componente Principal , Estações do Ano
3.
Sci Rep ; 8(1): 214, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29317759

RESUMO

Climate change and human activities cause uncertain changes to species biodiversity by altering their habitat. The uncertainty of climate change requires planners to balance the benefit and cost of making conservation plan. Here optimal protection approach for Lesser White-fronted Goose (LWfG) by coupling Modern Portfolio Theory (MPT) and Marxan selection were proposed. MPT was used to provide suggested weights of investment for protected area (PA) and reduce the influence of climatic uncertainty, while Marxan was utilized to choose a series of specific locations for PA. We argued that through combining these two commonly used techniques with the conservation plan, including assets allocation and PA chosing, the efficiency of rare bird's protection would be enhanced. In MPT analyses, the uncertainty of conservation-outcome can be reduced while conservation effort was allocated in Hunan, Jiangxi and Yangtze River delta. In Marxan model, the optimal location for habitat restorations based on existing nature reserve was identified. Clear priorities for the location and allocation of assets could be provided based on this research, and it could help decision makers to build conservation strategy for LWfG.


Assuntos
Algoritmos , Custos e Análise de Custo , Ecossistema , Espécies em Perigo de Extinção/economia , Gansos/fisiologia , Animais , China , Espécies em Perigo de Extinção/estatística & dados numéricos , Modelos Econômicos
4.
Ambio ; 46(Suppl 2): 198-209, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28215016

RESUMO

The Scottish island of Islay hosts 45 000 barnacle geese Branta leucopsis (56% of the Greenland barnacle goose population, plus those passing through on migration), 5000 Greenland white-fronted geese Anser albifrons flavirostris (up to 30% of the world population) and 2500 greylag geese Anser anser, most of which feed on 9000 ha of grassland. The financial impacts of estimated agricultural damage have risen greatly over the past 20 years due to increasing goose numbers and higher farming costs. Mechanisms implemented to resolve conflict over time are reviewed for their effectiveness. Emphasis is placed on coordinating the implementation of strategic national conflict resolution at a local scale where the relative pressure from internationally important concentrations of geese on agriculture is acute. Despite the "local" nature of this problem, the benefit from the experience of decades of attempted conflict resolution and the effectiveness of existing programmes can contribute much to the regional and flyway dimensions of this international issue.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Gansos/fisiologia , Herbivoria , Agricultura/economia , Animais , Escócia
5.
Ambio ; 46(Suppl 2): 224-230, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28215019

RESUMO

This paper reviews the changing status of goose populations in Scotland since the 1940s, and the changing policies and management activities employed over that time. The size of all goose populations has risen since the 1940s due to protection measures, changes in agriculture and levels of shooting, in the UK and elsewhere. The development of goose policies in response to public interest and pressures is described. Some changes in goose populations since 2000 can be linked to this policy development. Policy is now split between protective measures for some species and adaptive management approaches encompassing control measures for others. The paper identifies the importance of the social and economic concerns of some parties in the development of goose management approaches, rather than scientific advice based on goose population numbers and trends, and recognises that future goose policy will necessarily be a difficult compromise between wide ranging, and even opposing positions and views.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Política Ambiental/legislação & jurisprudência , Gansos/fisiologia , Animais , Formulação de Políticas , Dinâmica Populacional , Escócia
6.
J Wildl Dis ; 52(2 Suppl): S86-95, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26845303

RESUMO

Swan pipes, duck decoys, cage traps, cannon netting, and roundups are widely used to capture waterfowl in order to monitor populations. These methods are often regulated in countries with national ringing or banding programs and are considered to be safe, and thus justifiable given the benefits to conservation. However, few published studies have addressed how frequently injuries and mortalities occur, or the nature of any injuries. In the present study, rates of mortality and injury during captures with the use of these methods carried out by the Wildfowl & Wetlands Trust as part of conservation programs were assessed. The total rate of injury (including mild dermal abrasions) was 0.42% across all species groups, whereas total mortality was 0.1% across all capture methods. Incidence of injury varied among species groups (ducks, geese, swans, and rails), with some, for example, dabbling ducks, at greater risk than others. We also describe techniques used before, during, and after a capture to reduce stress and injury in captured waterfowl. Projects using these or other capture methods should monitor and publish their performance to allow sharing of experience and to reduce risks further.


Assuntos
Animais Selvagens/lesões , Anseriformes/lesões , Comportamento de Redução do Risco , Animais , Animais Selvagens/fisiologia , Anseriformes/fisiologia , Doenças das Aves/mortalidade , Doenças das Aves/prevenção & controle , Aves/lesões , Aves/fisiologia , Patos/lesões , Patos/fisiologia , Gansos/lesões , Gansos/fisiologia , Manobra Psicológica , Humanos , Roupa de Proteção , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/prevenção & controle , Ferimentos e Lesões/veterinária , Zoonoses/prevenção & controle
7.
J Anim Sci ; 93(5): 2124-33, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26020308

RESUMO

Chronic stress--or, more appropriately, "allostatic overload"--may be physiologically harmful and can cause death in the most severe cases. Animals in captivity are thought to be particularly vulnerable to allostatic overload due to artificial housing and group makeup. Here we attempted to determine if captive greylag geese (Anser anser), housed lifelong in captivity, showed elevated levels of immunoreactive corticosterone metabolites (CORT) and ectoparasites in dropping samples as well as some hematological parameters (hematocrit, packed cell volume, total white blood cell count [TWBC], and heterophil:lymphocyte ratio [H:L]). All of these have been measured as indicators of chronic stress. Furthermore, we correlated the various stress parameters within individuals. Captive geese showed elevated values of CORT and ectoparasites relative to a wild population sampled in the vicinity of the area where the captive flock is held. The elevated levels, however, were by no means at a pathological level and fall well into the range of other published values in wild greylag geese. We found no correlations between any of the variables measured from droppings with any of the ones collected from blood. Among the blood parameters, only the H:L negatively correlated with TWBC. We examine the problem of inferring allostatic overload when measuring only 1 stress parameter, as there is no consistency between various measurements taken. We discuss the different aspects of each of the parameters measured and the extensive individual variation in response to stress as well as the timing at which different systems respond to a stressor and what is actually measured at the time of data collection. We conclude that measuring only 1 stress parameter often is insufficient to evaluate the well-being of both wild and captively housed animals and that collecting behavioral data on stress might be a suitable addition.


Assuntos
Alostase/fisiologia , Fezes/química , Gansos/fisiologia , Estresse Fisiológico/fisiologia , Animais , Corticosterona/análise , Fezes/parasitologia , Gansos/parasitologia , Hematócrito/veterinária , Contagem de Leucócitos/veterinária , Estações do Ano , Fatores de Tempo
8.
Ambio ; 43(6): 801-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24668579

RESUMO

Wild geese foraging on farmland cause increasing conflicts with agricultural interests, calling for a strategic approach to mitigation. In central Norway, conflicts between farmers and spring-staging pink-footed geese feeding on pastures have escalated. To alleviate the conflict, a scheme by which farmers are subsidized to allow geese to forage undisturbed was introduced. To guide allocation of subsidies, an ecological-based ranking of fields at a regional level was recommended and applied. Here we evaluate the scheme. On average, 40 % of subsidized fields were in the top 5 % of the ranking, and 80 % were within the top 20 %. Goose grazing pressure on subsidized pastures was 13 times higher compared to a stratified random selection of non-subsidized pastures, capturing 67 % of the pasture feeding geese despite that subsidized fields only comprised 13 % of the grassland area. Close dialogue between scientists and managers is regarded as a key to the success of the scheme.


Assuntos
Agricultura , Conservação dos Recursos Naturais/métodos , Gansos/fisiologia , Animais , Conservação dos Recursos Naturais/economia , Comportamento Alimentar , Noruega , Estações do Ano
9.
PLoS One ; 8(8): e71912, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23977175

RESUMO

This paper presents results from a multidisciplinary study of a negotiation process between farmers and wildlife authorities which led to an agricultural subsidy scheme to alleviate conflicts between agriculture and geese in Norway. The Svalbard-breeding population of pink-footed geese Anser brachyrhynchus has increased considerably over the last decades and conflicts with farmers have escalated, especially at stopover sites in spring when geese feed on newly sprouted pasture grass. In Vesterålen, an important stopover site for geese in North Norway, farmers deployed scaring of geese at varying intensity dependent on the level of conflict during 1988-2012. We assessed the efficiency of a subsidy scheme established in 2006, in terms of its conflict mitigation, reflected in a near discontinuation of scaring activities. The presence of pink-footed geese was analysed in relation to scaring intensity, the total goose population size and the increasing occurrence of another goose species, the barnacle goose Branta leucopsis. Scaring significantly affected the number of geese staging in Vesterålen, both in absolute and relative terms (controlling for total population size). The geese responded immediately to an increased, and reduced, level of scaring. Despite the establishment of the subsidy scheme, the number of pink-footed geese has recently declined which is probably caused by the increasing number of barnacle geese. For the farmers, the subsidy scheme provides funding that reduces the economic costs caused by the geese. Sustaining a low level of conflict will require close monitoring, dialogue and adaptation of the subsidy scheme to cater for changes in goose population dynamics.


Assuntos
Agricultura/economia , Conservação dos Recursos Naturais , Gansos/fisiologia , Migração Animal , Animais , Cruzamento , Ingestão de Alimentos , Financiamento Governamental , Negociação , Noruega , Controle de Pragas , Dinâmica Populacional , Estações do Ano
10.
J Exp Biol ; 215(Pt 15): 2579-85, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22786634

RESUMO

Using open-flow respirometry and video footage (25 frames s(-1)), the energy expenditure and hindlimb kinematics of barnacle geese, Branta leucopsis, were measured whilst they were exercising on a treadmill at gradients of +7 and -7 deg, and on a level surface. In agreement with previous studies, ascending a gradient incurred metabolic costs higher than those experienced on level ground at comparable speeds. The geese, however, are the first species to show an increased duty factor when ascending a gradient. This increased duty factor was accompanied by a longer stance time, which was probably to enable the additional force required for ascending to be generated. Contrary to previous findings, the geese did not experience decreased metabolic costs when descending a gradient. For a given speed, the geese took relatively shorter and quicker strides when walking downhill. This 'choppy' stride and perhaps a lack of postural plasticity (an inability to adopt a more crouched posture) may negate any energy savings gained from gravity's assistance in moving the centre of mass downhill. Also contrary to previous studies, the incremental increase in metabolic cost with increasing speed was similar for each gradient, indicating that the efficiency of locomotion (mechanical work done/chemical energy consumed) is not constant across all walking speeds. The data here suggest that there are species-specific metabolic responses to locomotion on slopes, as well as the established kinematics differences. It is likely that a suite of factors, such as ecology, posture, gait, leggedness and foot morphology, will subtly affect an organism's ability to negotiate gradients.


Assuntos
Metabolismo Energético/fisiologia , Marcha/fisiologia , Gansos/fisiologia , Caminhada/fisiologia , Animais , Fenômenos Biomecânicos/fisiologia , Modelos Lineares , Locomoção/fisiologia , Consumo de Oxigênio/fisiologia , Fatores de Tempo
12.
J Anim Ecol ; 79(5): 974-82, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20579179

RESUMO

1. It has been known for some time that the consequences of 'decisions' made at one point in an animal's life may not always be borne immediately. For example, numerous studies have demonstrated the trade-off between current and future breeding success across multiple taxa. 2. It is becoming increasingly clear that such processes may also operate among seasons, such that the conditions experienced at one point in the annual cycle may have significant downstream impacts, or 'carry-over effects', and this is particularly evident among migratory species. We might therefore predict that certain combinations of reproductive and migratory strategy could lead to profound carry-over effects. However, the extent to which these phenomena might generate variation in fitness within a population is unclear. 3. Here, we investigate how winter habitat selection in a long-distance migrant, with extended parental care (the Light-bellied Brent goose) is influenced by parental status and how this has a counterintuitive effect on subsequent breeding success. 4. Dominant individuals and groups generally monopolize the best quality resources. In the case of geese, families are dominant; however, our findings highlight a hidden cost to raising a family. Stable isotope analysis demonstrates that later in the non-breeding season, adults with families utilize lower quality resources than non-breeders. This is probably caused by parents being constrained in habitat choice by the lower foraging efficiency of their juveniles. Consequently, parental adults end the winter in poorer condition than non-breeders. 5. We further demonstrate that parents in one year are less likely than expected to breed again in the next year and suggest that this is caused by conditions during the non-breeding period being carried over into the breeding season. In conclusion, we demonstrate previously hidden costs to raising a family, which are likely to be important in terms of life-history evolution.


Assuntos
Migração Animal , Gansos/fisiologia , Reprodução/fisiologia , Animais , Ecossistema , Estações do Ano , Predomínio Social , Fatores de Tempo
13.
Theriogenology ; 59(7): 1627-40, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12559467

RESUMO

Individual differences in gander Anser anser L. reaction to semen collection procedure, quality and quantity of fresh semen and its susceptibility to the freezing process are discussed. Semen was collected individually by dorso-abdominal massage, from 1-year old White Koluda ganders (n = 12) every 2-3 days. Ganders' reactions to massage were observed during the entire reproductive cycle (from 11 February to 13 June, from every male 40 semen collections were performed). For individual evaluation and freezing purpose semen was collected 13 times from every male. In the fresh semen, the following parameters were evaluated: ejaculate volume, color, density, blood or fecal contamination, motility, concentration and morphology of spermatozoa. Motility and spermatozoa morphology were evaluated in the frozen-thawed semen. Semen diluted in 2:1 ratio with EK diluent was frozen with 6% of dimethyl-formamide (DMF) to -140 degrees C at a rate 60 degrees C/min. Semen was thawed by placing the straws in a 60 degrees C water-bath for 4-5 s. Ten out of 12 ganders had from 67.5 to 100.0% positive reactions resulting in semen ejaculation. Significant (P < or = 0.01) differences in fresh semen quality of particular ganders were observed for all evaluated traits. In 1-year-old gander semen morphologically intact spermatozoa constitute only 27.8-45.2% of all cells. Therefore, the sperm quality factor (SQF), proposed by the authors, which includes ejaculate volume, sperm concentration and the percentage of live normal spermatozoa, seems to be a good predictor of gander semen fertilizing ability. The SQF of individual ganders varied from 7.7 to 11.5. The percentage of live normal spermatozoa in the frozen-thawed semen depended mainly on fresh semen quality. In relation to the fresh semen average from 57.2 to 63.2% of spermatozoa survived freezing process and from 23.9 to 38.5% remained morphologically intact.


Assuntos
Criopreservação/veterinária , Gansos/fisiologia , Preservação do Sêmen/veterinária , Sêmen/citologia , Espermatozoides/fisiologia , Animais , Criopreservação/métodos , Dimetilformamida/farmacologia , Masculino , Preservação do Sêmen/métodos , Manejo de Espécimes/veterinária , Contagem de Espermatozoides/veterinária , Motilidade dos Espermatozoides , Espermatozoides/efeitos dos fármacos
14.
Avian Dis ; 28(2): 526-31, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6743183

RESUMO

The efficacy of flubendazole food medication against roundworms in geese was determined under controlled field conditions. The geese were infected with Amidostomum anseris, Capillaria anseris, Trichostrongylus tennis, and Syngamus trachea. Medicated food was given for 7 consecutive days at a level of 30 ppm. Anthelmintic activity, egg production, and hatchability were recorded. Flubendazole medication resulted in a 100% worm elimination, no consistent change in egg-lay performance, and a highly significant increase in hatchability.


Assuntos
Antinematódeos/uso terapêutico , Benzimidazóis/uso terapêutico , Gansos/parasitologia , Mebendazol/uso terapêutico , Infecções por Nematoides/veterinária , Doenças das Aves Domésticas/tratamento farmacológico , Animais , Antinematódeos/farmacologia , Feminino , Gansos/fisiologia , Masculino , Mebendazol/análogos & derivados , Mebendazol/farmacologia , Nematoides/efeitos dos fármacos , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Oviposição , Doenças das Aves Domésticas/parasitologia
15.
Am J Physiol ; 241(5): E342-54, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7304738

RESUMO

Starvation in 15 geese (mean initial body mass, m = 6.3 kg) fasting for about 40 days (mean decrease in m = 2.5 kg) was characterized by three periods. Period I (3-8 days), an adaptation period, was marked by a considerable decrease in the daily rate of change in m (dm) as well as in resting metabolic rate (RMR), and by high fat mobilization. In period II (a period of economy) the decreases in dm, RMR, and daily rate of nitrogen excretion (dne) were reduced: when expressed per unit of body mass these rates were either constant or decreased slightly. Period III, a critical period, was characterized by a rapid increase in both dm and dne that appeared when body mass had dropped to 4.7-3.2 kg. In parallel there was a greater decrease in intracellular fluid volume below 5 kg. Throughout the fast, in contrast to fasting mammals, plasma glucose and alanine concentrations were maintained at high levels (8-10 and 0.4 mM, respectively), and there was no increase in acetoacetate. However, after 20 days of fasting, plasma beta-hydroxybutyrate concentration (beta-OHB) increased to about 20 mM, while blood pH remained constant and blood PCO2 decreased. Thus, compensation for metabolic acidosis was partly attributed to respiratory alkalosis. Throughout the fast, the variations in beta-OHB were a mirror image of those for daily changes in body mass and in nitrogen excretion. This presumably reflects a hormonal change, but might also suggest a key role of beta-OHB in the control of energy expenditure and/or in regulation of body mass as well as in protein sparing.


Assuntos
Alanina/sangue , Glicemia/metabolismo , Composição Corporal , Metabolismo Energético , Jejum , Ácidos Graxos não Esterificados/sangue , Gansos/fisiologia , Tecido Adiposo/anatomia & histologia , Animais , Temperatura Corporal , Concentração de Íons de Hidrogênio , Corpos Cetônicos/sangue , Cinética , Músculos/anatomia & histologia , Nitrogênio/metabolismo
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