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1.
J Environ Qual ; 49(4): 869-881, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33016484

RESUMO

The success of poultry litter reuse in U.S. poultry production can be attributed to the efficient treatment methods used by producers during downtimes (the time lapse between consecutive flocks, during which the broiler house is empty). During this period, reused litter may be decaked, tilled/windrowed, or treated with acid-based amendments to reduce ammonia and bacteria levels. Competitive exclusion, pH, and temperature are proposed factors that influence the level of pathogens and the overall litter microbiome during downtimes. We previously reported on the bacterial genetic factors associated with the fitness of two strains of Salmonella enterica serovar Heidelberg (SH) incubated for 14 d in reused litter. Here, we investigated the physicochemical parameters and the microbiome of the litter correlating with SH abundance during this period. We used 16S ribosomal RNA gene sequencing to determine the litter microbiome and whole genome sequencing to characterize bacteria with competitive exclusion potential against SH. The ß diversity of the litter microbiome was significantly affected by the duration of incubation, microcosm, and microcosm plus Heidelberg strain combinations. In addition, ß diversity was significantly affected by litter parameters, including NH4 , pH, moisture, water activity, and aluminum. The major phyla observed in the reused litter throughout the 14-d incubation experiment were Firmicutes and Actinobacteria, although their abundance differed by microcosm and time. Amplicon-specific variants homologous to the members of the genera Nocardiopsis and Lentibacillus and the family Bacillaceae_2 were found to significantly correlate with the abundance of Salmonella. A consortium of Bacillus subtilis strains isolated from the litter microcosms reduced the growth of SH in vitro.


Assuntos
Microbiota , Salmonella enterica , Animais , Galinhas , Abrigo para Animais , Aves Domésticas , Salmonella
2.
Rev Sci Tech ; 39(2): 417-425, 2020 Aug.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-33046933

RESUMO

This case study outlines the actions of Cuba's Veterinary Service, as part of the country's disaster risk reduction and management system, in response to Hurricane Irma. The phenomenon affected ten of Cuba's 15 provinces and caused significant damage in 53 of its municipalities (29.6%). During the response effort, the pre-established measures for the various phases (warning, alert and emergency) were deployed according to the disaster reduction plans for each level. In all provinces, animals were protected by moving them to safer locations, allowing for pre-established sanitary measures and technical assistance. Nonetheless, damage was incurred, mainly to the roofs of some animal housing. The following deaths were recorded: 210,150 poultry, 2,752 cattle (of which 73.8% were calves) and 866 pigs (of which 68% were young animals). In addition, 7% of the inventory of hives was damaged and 3.3% of hives were lost. Damage to infrastructure included: 466 poultry houses, 1,422 cattle houses, 431 pig houses, 1,200 wind pumps and 13 of the country's 17 feed concentrate plants. As no major damage was reported to the Veterinary Service's facilities (laboratories and offices), its viability was guaranteed at all times. Rapid damage assessment enabled priorities for rehabilitation and recovery actions to be set, with the result that, just three months after the hurricane had struck, 67% of the poultry houses and 33% of the pig houses had been restored. This article focuses on preparedness, response and lessons learned.


Assuntos
Tempestades Ciclônicas , Planejamento em Desastres , Desastres , Animais , Bovinos , Cuba , Abrigo para Animais , Suínos
3.
Viruses ; 12(9)2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911718

RESUMO

The aim of this prospective study was to determine prevalence and potential risk factors of feline coronavirus (FCoV) shedding. Four consecutive fecal samples of 179 cats from 37 German breeding catteries were analyzed for FCoV ribonucleic acid (RNA) by real-time reverse transcriptase polymerase chain reaction (RT-qPCR). Prevalence of shedding was calculated using different numbers of fecal samples per cat (1-4) and different sampling intervals (5-28 days). Information on potential risk factors for FCoV shedding was obtained by a questionnaire. Risk factor analysis was performed using a generalized linear mixed model (GLMM). Most cats (137/179, 76.5%, 95% confidence interval (CI) 69.8-82.2) shed FCoV at least at once. None of the tested 37 catteries was free of FCoV. Prevalence calculated including all four (76.5%, 95% CI 69.8-82.2) or the last three (73.7%, 95% CI 66.8-79.7) samples per cat was significantly higher than the prevalence calculated with only the last sample (61.5%, 95% CI 54.2-68.3; p = 0.0029 and 0.0175, respectively). Young age was significantly associated with FCoV shedding while the other factors were not. For identification of FCoV shedders in multi-cat households, at least three fecal samples per cat should be analyzed. Young age is the most important risk factor for FCoV shedding.


Assuntos
Doenças do Gato/virologia , Infecções por Coronavirus/veterinária , Coronavirus Felino/isolamento & purificação , Fatores Etários , Criação de Animais Domésticos , Animais , Doenças do Gato/epidemiologia , Gatos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Fezes/virologia , Peritonite Infecciosa Felina/epidemiologia , Peritonite Infecciosa Felina/virologia , Feminino , Alemanha , Abrigo para Animais , Modelos Lineares , Masculino , Prevalência , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Instalações de Eliminação de Resíduos
4.
Life Sci ; 258: 118214, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32768585

RESUMO

Large numbers of rodents are often used in the study of disease progression and in the evaluation of its potential treatments. To avoid subjective observation and to minimize home cage interference, we developed a computerized home cage monitoring system (HCMS100) based on a standard cage rack adapted with a single laser beam and a detector mounted on each cage, enabling to monitor mice movements based on laser beam interruptions. This retrofit system provided continuous and uninterrupted monitoring of spontaneous movement of a group of mice in a home cage. Validity was evaluated using disease state induced by LPS modelling bacterial infection and by influenza virus. RESULTS: Spontaneous activity of different number of mice (2-8) per cage showed the expected circadian rhythm with increased activity during the night, and its extent dependent on the number of mice in the cage. Females and males show similar circadian rhythm. Intranasal LPS administration and pulmonary infection with live influenza virus resulted in major reduction of mice activity along disease progression. Increase in activity over time was a good indicator of the recovery process from both LPS exposure and the flu infection. CONCLUSIONS: HCMS100 was shown to be a reliable, inexpensive, easy to use system that requires no changes in the common housing of various experimental animals (mice, hamsters, rats etc.). With minimal intervention, HCMS100 provides a continuous record of group activity with clear pattern of circadian rhythm, allowing long term recording of home cage activity even in restricted access environments.


Assuntos
Progressão da Doença , Abrigo para Animais , Lipopolissacarídeos/toxicidade , Infecções por Orthomyxoviridae/fisiopatologia , Orthomyxoviridae , Recuperação de Função Fisiológica/fisiologia , Animais , Ritmo Circadiano/fisiologia , Feminino , Abrigo para Animais/tendências , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Infecções por Orthomyxoviridae/psicologia , Recuperação de Função Fisiológica/efeitos dos fármacos
5.
PLoS Biol ; 18(7): e3000411, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32663221

RESUMO

Improving the reproducibility of biomedical research is a major challenge. Transparent and accurate reporting is vital to this process; it allows readers to assess the reliability of the findings and repeat or build upon the work of other researchers. The ARRIVE guidelines (Animal Research: Reporting In Vivo Experiments) were developed in 2010 to help authors and journals identify the minimum information necessary to report in publications describing in vivo experiments. Despite widespread endorsement by the scientific community, the impact of ARRIVE on the transparency of reporting in animal research publications has been limited. We have revised the ARRIVE guidelines to update them and facilitate their use in practice. The revised guidelines are published alongside this paper. This explanation and elaboration document was developed as part of the revision. It provides further information about each of the 21 items in ARRIVE 2.0, including the rationale and supporting evidence for their inclusion in the guidelines, elaboration of details to report, and examples of good reporting from the published literature. This document also covers advice and best practice in the design and conduct of animal studies to support researchers in improving standards from the start of the experimental design process through to publication.


Assuntos
Experimentação Animal , Guias como Assunto , Relatório de Pesquisa , Experimentação Animal/ética , Criação de Animais Domésticos , Animais , Intervalos de Confiança , Abrigo para Animais , Avaliação de Resultados em Cuidados de Saúde , Publicações , Distribuição Aleatória , Reprodutibilidade dos Testes , Tamanho da Amostra
6.
Anim Sci J ; 91(1): e13400, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32512640

RESUMO

Biochemical and hematological examination of blood and individual assessment of the birds were performed in Lohman Brown laying hens at 45 weeks of age housed in different systems. The biochemical examination revealed higher (p < .01) corticosterone levels, creatine kinase, and aspartate aminotransferase activity and lower (p < .01) levels of lactate, triglycerides, albumin, calcium, and phosphorus in aviary hens compared to hens housed in furnished cages. Hematological examination of hens housed in aviaries revealed higher (p < .05) hematocrit, leukocytes, heterophils, eosinophils, basophils, monocytes, and H/L ratio. Furthermore, hens housed in aviaries had lower (p < .01) body weight than hens in furnished cages, they were worse feathered (p < .001), had more damaged combs (p < .05), and poorer physical condition (p < .01). In contrast, caged hens showed worse (p < .01) feather condition of the wings due to abrasion and claws due to overgrowth. The results have shown that the housing system has a significant impact on the internal environment and condition of birds and that housing in aviaries without taking into account the specifics of such housing may lead to significant stress and disturbance to the welfare of laying hens.


Assuntos
Criação de Animais Domésticos , Galinhas/metabolismo , Galinhas/fisiologia , Meio Ambiente , Abrigo para Animais , Bem-Estar do Animal , Animais , Peso Corporal , Corticosterona/sangue , Creatina Quinase/sangue , Plumas/patologia , Feminino , Oviposição
7.
Top Companion Anim Med ; 39: 100430, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32482287

RESUMO

According to American Veterinary Medical Association statistics, veterinarians employed in the not-for-profit sector account for the smallest group by type of employment. However, this group has experienced the greatest amount of change, with an increase of 52% between 2008 and 2013 and 55% between 2013 and 2018. Despite this growth, there has been a paucity of information regarding the salary, benefits, hours, and job duties that come with a career in shelter medicine. An initial survey of shelter medicine salary, benefits, hours, and job duties was conducted in 2011, and a similar survey conducted in 2018. All responses were anonymous. Results from 2018 were compared to 2011 using 2 sample test of proportions (counts) or Mann-Whitney (Wilcoxon rank sum) test (medians). A total of 207 conforming responses were received in 2011, and 219 in 2018. Median salary for all full-time veterinarians in the field of shelter medicine was $75,000 (interquartile range [IQR], 65,000-85,000) in 2011 and $94,500 (IQR, 80,000-110,000) in 2018. Part-time shelter employed veterinarians in 2011 worked a median of 20 hours (IQR 7-28) for an hourly rate of $41 (IQR, 29-56) while they worked a median of 26 hours (IQR, 15-32) for an hourly rate of $48 (IQR, 36-66) in 2018. There was an increase in the provision of all categories of benefits and an increase in veterinarians employed in academia and leadership. Demographics were similar, with the exception of increases in the number of boarded specialists and veterinarians who had completed a residency. Veterinarians reporting that shelter medicine had been offered in their curriculum increased by 44%. Budgets for shelters were reported to be higher, while animal intake and daily count of animals in care was lower. Comparison between surveys of shelter medicine veterinarians in 2011 and 2018 showed a consistent increase in salary, benefits and resources. There were indicators that the field of shelter medicine has matured as a discipline, particularly with regard to the availability of shelter medicine education and increased number of boarded specialists.


Assuntos
Abrigo para Animais , Animais de Estimação , Salários e Benefícios , Médicos Veterinários/economia , Carga de Trabalho , Adulto , Animais , Feminino , Humanos , Masculino , Estados Unidos
8.
PLoS One ; 15(6): e0234922, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32559221

RESUMO

If a laboratory animal survives an experiment without lasting compromised welfare, its future must be negotiated. Rehoming may be a consideration. This paper reports on research findings that provide an indication of the uptake of animal rehoming by UK facilities and the associated moral, ethical, practical and regulatory considerations that inform decisions to rehome or not. This research addresses a widely acknowledged gap in the literature to understand both the numbers, and types of animals rehomed from UK research facilities, as well as the main motivations for engaging in the practice, and the barriers for those facilities not currently rehoming. From the ~160 UK research facilities in the UK, 41 facilities completed the questionnaire, giving a response rate of approximately 25%. Results suggest rehoming occurs routinely, yet the numbers are small; just 2322 animals are known to have been rehomed between 2015-2017. At least 1 in 10 facilities are rehoming. There exists a clear preference for the rehoming of some species (mainly cats, dogs and horses) over others (rodents, agricultural animals and primates). Indeed, although 94.15% of species kept in laboratories are rodents, they make up under a fifth (19.14%) of all animals known to be rehomed between 2015-2017. The primary motivation for rehoming is to boost staff morale and promote a positive ethical profile for the facility. Barriers include concern for the animal's welfare following rehoming, high scientific demand for animals that leaves few to be rehomed, and, finally, certain animals (mainly those genetically modified) are simply unsuited to rehoming. The findings of this research will support facilities choosing to rehome, as well as those that are not currently engaging in the practice. By promoting the practice, the benefits to rehoming in terms of improving laboratory animal's quality of life, helping facility staff to overcome the moral stress of killing, and addressing public concern regarding the fate of laboratory animals, can be attained. It is only once an understanding of rehoming from the perspective of UK research facilities has been ascertained, that appropriate policy and support can be provided.


Assuntos
Experimentação Animal/estatística & dados numéricos , Bem-Estar do Animal/estatística & dados numéricos , Animais de Laboratório , Abrigo para Animais/estatística & dados numéricos , Inquéritos e Questionários , Experimentação Animal/ética , Experimentação Animal/normas , Bem-Estar do Animal/ética , Bem-Estar do Animal/normas , Animais , Abrigo para Animais/ética , Abrigo para Animais/normas , Humanos , Motivação , Guias de Prática Clínica como Assunto , Reino Unido
9.
PLoS Negl Trop Dis ; 14(5): e0008254, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32365060

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) or Kala-azar has been a major public health problem in Bihar, India, for several decades. A few VL infected districts including Vaishali have reported >600 cases annually. Hence, in 2015, the Government of India entrusted ICMR-Rajendra Memorial Research Institute of Medical Sciences, Patna, to implement an integrated control strategy for achieving the VL elimination target (<1 case per 10,000 people at the block level) in the Vaishali District of Bihar. METHODOLOGY: This study was conducted between January 2015 and December 2016. An integrated control strategy including the spatio-temporal mapping of VL-case distribution, active case detection, chemical-based vector control using indoor residual spraying (IRS), community awareness campaigns, the training of IRS members, the training of medical doctors for effective treatment, daily monitoring and the supervision of IRS activities, logistic management, post-IRS quality assurance, epidemiological surveillance, and entomological monitoring was performed. An insecticide quantification test was performed for evaluating the IRS quality on sprayed walls. A modern compression pump was used to maintain spray quality on different wall surfaces. The impact of IRS was assessed through sand fly collection in human dwellings and cattle sheds in pre- and post-IRS. The insecticide susceptibility of local P. argentipes was performed before each IRS round (in February and June) during 2015-2016. Statistical analysis such as the mean, percentage, and 95% CI were used to summarize the results. FINDINGS: All 16 blocks of the Vaishali District achieved the VL elimination target in 2016. The integrated VL control strategy helped reduce the number of VL cases from 664 in 2014 to 163 in 2016 and the number of endemic villages from 282 in 2014 to 142 in 2016. The case reduction rate was increased from 22.6% in 2014 to 58.8% in 2016. On average, 74 VL infected villages became Kala-azar free each year from 2015 to 2016. CONCLUSIONS: The results of this study suggest that the elimination of VL is possible from all endemic blocks of Bihar if the integrated Vaishali VL control strategy is applied under strong monitoring and supervision.


Assuntos
Controle de Doenças Transmissíveis/métodos , Controle de Doenças Transmissíveis/organização & administração , Erradicação de Doenças , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/prevenção & controle , Animais , Bovinos , Doenças Endêmicas , Características da Família , Feminino , Abrigo para Animais , Humanos , Índia/epidemiologia , Masculino , Resultado do Tratamento
10.
Vet Clin North Am Food Anim Pract ; 36(2): 375-383, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32451031

RESUMO

Confined cow-calf operations are a relatively new production model in the United States. As with any new technology, there will be a learning curve for producers and veterinarians as we attempt to optimize animal health and profitability. It is critical that cattle are managed properly in these units if disease issues are to be minimized. Allowing for adequate space in the pen and at the feed bunk is a critical factor affecting animal welfare, nutritional management, and disease transmission.


Assuntos
Criação de Animais Domésticos/métodos , Complexo Respiratório Bovino/etiologia , Abrigo para Animais/normas , Criação de Animais Domésticos/normas , Bem-Estar do Animal , Animais , Bovinos , Feminino , Gravidez , Estados Unidos
11.
Vet Clin North Am Food Anim Pract ; 36(2): 385-398, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32451032

RESUMO

Bovine respiratory disease (BRD) is a leading cause of morbidity and mortality in young cattle. Housing factors that lead to poor ventilation and stagnant air are often considered the primary reasons for high levels of endemic disease. This article reviews the literature from the past 40 years in order to determine which housing factors have been associated with respiratory disease. Penning strategy and its affect on calf respiratory health were most commonly studied. The wide variation in disease definitions and quality of reporting make drawing conclusions from the available literature extraordinarily difficult.


Assuntos
Complexo Respiratório Bovino/etiologia , Indústria de Laticínios/métodos , Abrigo para Animais/normas , Animais , Complexo Respiratório Bovino/epidemiologia , Bovinos , Indústria de Laticínios/normas , Indústria de Laticínios/estatística & dados numéricos , Feminino , Abrigo para Animais/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/veterinária , Estados Unidos/epidemiologia , Ventilação
12.
PLoS One ; 15(5): e0233530, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437406

RESUMO

In animal studies on bone healing, the effect of housing space and physical activity are seldom taken into account. Bone formation was evaluated in New Zealand White rabbits (mean ± SEM BW: 3.9 ± 0.11 kg) with a critical bone defect after 12 weeks of rehabilitation in pair-housing in 3 m2 large floor pens (Floor, n = 10) or standard single housing in 0.43 m2 cages (Cage, n = 10). In the randomised full-factorial study, a bone replica of calcium phosphate cement (CPC, n = 10) or autologous bone (AB, n = 10) was implanted in the unilateral 20 mm radius defect. Post-mortem, the oxidative capacity was measured by citrate synthase (CS) activity in M. quadriceps and the defect filling volume and density evaluated by microcomputer tomography (µ-CT). Histology sections were evaluated by subjective scoring and histomorphometry. Fourteen rabbits remained until the end of the study. Group Floor (n = 7; 3 CPC + 4 AB) had a higher CS activity and a larger bone defect filling volume and lower density by µ-CT measurements than group Cage (n = 7; 3 CPC + 4 AB). Three out of four rabbits in AB-Floor presented fusion of the defect with reorganisation of trabecular bone, whereas three of four in AB-Cage showed areas of incomplete healing. Floor rabbits had a higher score of bony fusion between the radius and ulna than Cage rabbits. There were no differences between groups in histomorphometry. The study found that a larger housing space increased physical activity and promoted bone formation.


Assuntos
Osteogênese , Rádio (Anatomia)/lesões , Animais , Cimentos para Ossos/uso terapêutico , Substitutos Ósseos/uso terapêutico , Transplante Ósseo , Fosfatos de Cálcio/uso terapêutico , Feminino , Abrigo para Animais , Coelhos , Rádio (Anatomia)/patologia , Rádio (Anatomia)/fisiologia , Cicatrização
13.
PLoS One ; 15(5): e0232853, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374780

RESUMO

OBJECTIVE: The choice of the most suitable litter treatment should be based on scientific evidence. This systematic review assessed the effectiveness of litter treatments on ammonia concentration, pH, moisture and pathogenic microbiota of the litter and their effects on body weight, feed intake, feed conversion and mortality of broilers. METHODS: The systematic literature search was conducted using PubMed (Medline), Google Scholar, ScienceDirect and Scielo databases to retrieve articles published from January 1998 to august 2019. Means, standard deviations and sample sizes were extracted from each study. The response variables were analyzed using the mean difference (MD) or standardized mean difference (SMD), (litter treatment minus control group). All variables were analyzed using random effects meta-analyses. RESULTS: Subgroup meta-analysis revealed that acidifiers reduce pH (P<0.001), moisture (P = 0.002) ammonia (P = 0.011) and pathogenic microbiota (P <0.001) of the litter and improves the weight gain (P = 0.019) and decreases the mortality rate of broilers (P<0.001) when compared with controls. Gypsum had a positive effect on ammonia reduction (P = 0.012) and improved feed conversion (P = 0.023). Alkalizing agents raise the pH (P = 0.035), worsen feed conversion (P<0.001), increase the mortality rate (P <0.001), decrease the moisture content (P<0.001) and reduce the pathogenic microbiota of the litter (P<0.001) once compared to controls. Superphosphate and adsorbents reduce, respectively, pH (P<0.001) and moisture (P = 0.007) of the litter compared to control groups. CONCLUSION: None of the litter treatments influenced the feed intake of broilers. Meta-analyses of the selected studies showed positive and significant effects of the litter treatments on broiler performance and litter quality when compared with controls. Alkalizing was associated with worse feed conversion and high mortality of broilers.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Abrigo para Animais , Ácidos/análise , Ácidos/farmacologia , Ácidos/toxicidade , Álcalis/análise , Álcalis/farmacologia , Álcalis/toxicidade , Amônia/análise , Ração Animal , Animais , Doenças das Aves/mortalidade , Peso Corporal , Galinhas/crescimento & desenvolvimento , Comportamento Alimentar , Abrigo para Animais/estatística & dados numéricos , Umidade , Concentração de Íons de Hidrogênio , Microbiota , Gerenciamento de Resíduos , Ganho de Peso
14.
PLoS One ; 15(5): e0225488, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32453751

RESUMO

For (metabolic) research models using mice, singly housing is widely used for practical purposes to study e.g. energy balance regulation and derangements herein. Mouse (social) housing practices could however influence study results by modulating (metabolic) health outcomes. To study the effects of the social housing condition, we assessed parameters for energy balance regulation and proneness to (diet induced) obesity in male C57Bl/6J mice that were housed individually or socially (in pairs) directly after weaning, both at standard ambient temperature of 21°C. During adolescence, individually housed mice had reduced growth rate, while energy intake and energy expenditure were increased compared to socially housed counterparts. At 6 weeks of age, these mice had reduced lean body mass, but significantly higher white adipose tissue mass compared to socially housed mice, and higher UCP-1 mRNA expression in brown adipose tissue. During adulthood, body weight gain of individually housed animals exceeded that of socially housed mice, with elevations in both energy intake and expenditure. At 18 weeks of age, individually housed mice showed higher adiposity and higher mRNA expression of UCP-1 in inguinal white but not in brown adipose tissue. Exposure to an obesogenic diet starting at 6 weeks of age further amplified body weight gain and adipose tissue deposition and caused strong suppression of inguinal white adipose tissue mRNA UCP-1 expression. This study shows that post-weaning individual housing of male mice impairs adolescent growth and results in higher susceptibility to obesity in adulthood with putative roles for thermoregulation and/or affectiveness.


Assuntos
Metabolismo Energético , Abrigo para Animais , Obesidade/metabolismo , Proteína Desacopladora 1/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Composição Corporal , Regulação da Temperatura Corporal , Peso Corporal , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ingestão de Energia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Desmame
15.
Nature ; 583(7818): 834-838, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32408338

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus with high nucleotide identity to SARS-CoV and to SARS-related coronaviruses that have been detected in horseshoe bats, has spread across the world and had a global effect on healthcare systems and economies1,2. A suitable small animal model is needed to support the development of vaccines and therapies. Here we report the pathogenesis and transmissibility of SARS-CoV-2 in golden (Syrian) hamsters (Mesocricetus auratus). Immunohistochemistry assay demonstrated the presence of viral antigens in nasal mucosa, bronchial epithelial cells and areas of lung consolidation on days 2 and 5 after inoculation with SARS-CoV-2, followed by rapid viral clearance and pneumocyte hyperplasia at 7 days after inoculation. We also found viral antigens in epithelial cells of the duodenum, and detected viral RNA in faeces. Notably, SARS-CoV-2 was transmitted efficiently from inoculated hamsters to naive hamsters by direct contact and via aerosols. Transmission via fomites in soiled cages was not as efficient. Although viral RNA was continuously detected in the nasal washes of inoculated hamsters for 14 days, the communicable period was short and correlated with the detection of infectious virus but not viral RNA. Inoculated and naturally infected hamsters showed apparent weight loss on days 6-7 post-inoculation or post-contact; all hamsters returned to their original weight within 14 days and developed neutralizing antibodies. Our results suggest that features associated with SARS-CoV-2 infection in golden hamsters resemble those found in humans with mild SARS-CoV-2 infections.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Modelos Animais de Doenças , Pulmão/patologia , Pulmão/virologia , Mesocricetus/virologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Aerossóis , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/virologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Antígenos Virais/isolamento & purificação , Antígenos Virais/metabolismo , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Betacoronavirus/metabolismo , Brônquios/patologia , Brônquios/virologia , Infecções por Coronavirus/imunologia , Duodeno/virologia , Fômites/virologia , Abrigo para Animais , Rim/virologia , Masculino , Mesocricetus/imunologia , Mucosa Nasal/virologia , Pandemias , Pneumonia Viral/imunologia , RNA Viral/análise , Carga Viral , Perda de Peso
16.
Avian Dis ; 64(1): 46-52, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32267124

RESUMO

Rodents serve as amplifiers of Salmonella infections in poultry flocks and can serve as a source of Salmonella contamination in the environment even after thorough cleaning and disinfection. This study aims to determine the dynamics of Salmonella occurrence in rodents and its relation to Salmonella contamination in the layer farm environment, including air dusts and eggs. From 2008 to 2017, roof rats (Rattus rattus), environmental swabs, air dusts, and eggs were collected from an intensive commercial layer farm in East Japan and were tested for Salmonella spp. using standard procedures. In roof rat samples, the Salmonella isolation rate was reached at 10% (95% confidence interval [CI] 8.1-21.9) in which Salmonella Corvallis, Salmonella Infantis, Salmonella Potsdam, and Salmonella Mbandaka were the frequent isolates from the cecal portion of the intestines. On the other hand, the prevalence rate of Salmonella in environmental swabs was at 5.1% (95% CI 2.2-7.4) while air dusts were at 0.9% (95% CI 0.2-1.8). It was observed that the prevalence of predominant Salmonella serotypes shifted over time; in roof rats, it was noted that Salmonella Potsdam gradually replaced Salmonella Infantis. In environmental swabs and eggs, Salmonella Corvallis and Salmonella Potsdam increased significantly while Salmonella Infantis became less frequent. In air dusts, Salmonella Corvallis was observed to decrease and Salmonella Potsdam became more common. Based on our findings, the role of roof rats in the epidemiology of Salmonella in layer farms was expanded from being a reservoir and an amplifier host into a shifting vessel of the most predominant serotypes.


Assuntos
Galinhas , Doenças das Aves Domésticas/transmissão , Ratos , Salmonelose Animal/transmissão , Salmonella/fisiologia , Animais , Abrigo para Animais , Japão/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Prevalência , Salmonelose Animal/epidemiologia , Salmonelose Animal/microbiologia
17.
Environ Sci Pollut Res Int ; 27(17): 21680-21691, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279257

RESUMO

This study monitored concentrations and emissions of ammonia (NH3), hydrogen sulfide (H2S), and respirable dust for a commercial broiler and a cage-layer barn in the Canadian Prairies over a year between March 2015 and February 2016. Seasonal concentration and emission profiles were acquired by monthly measurements, while diurnal profiles were generated in different seasons. The indoor air quality was evaluated considering both the individual and the additive health effect (respiratory irritation) of the three air pollutants. In winter, both 8-h and 15-min exposure limits (threshold concentrations) of NH3 were exceeded in the broiler barn; the highest additive level was more than two times of the limit. Seasonal average emissions of NH3, H2S, and respirable dust were 57 g d-1 AU-1, 1.35 g d-1 AU-1, and 1.99 g d-1 AU-1, respectively, for the layer barn, all with higher levels in the mild and warm seasons than in the cold season. The emission data were only obtained for the worst-case scenarios (last week of the production cycle) of the broiler barn, with annual averages of 92 g d-1 AU-1 for NH3, 1.19 g d-1 AU-1 for H2S, and 4.32 g d-1 AU-1 for respirable dust, with obvious higher NH3 levels in winter. Additionally, manure removal once every 3-4 days for the layer barn reduced NH3 emissions by 62% and 90% in the cold and mild seasons, respectively. This study also found significant negative influence of outdoor T (Tout) on NH3 emissions for the broiler barn but positive impact of Tout on NH3 emissions for the layer barn.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Amônia/análise , Animais , Canadá , Galinhas , Pradaria , Abrigo para Animais
18.
Vet Rec ; 186(14): 434-435, 2020 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-32299966

RESUMO

Georgina Mills reports on new research showing the benefits of housing rabbits together.


Assuntos
Abrigo para Animais , Coelhos/psicologia , Comportamento Social , Bem-Estar do Animal , Animais , Temperatura Corporal , Estações do Ano , Estresse Psicológico/prevenção & controle
19.
J Dairy Sci ; 103(6): 5455-5465, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32278561

RESUMO

The objectives of this study were to (1) describe the calving location of dairy cattle given access to a pasture and barn; (2) identify factors associated with calving location; and (3) compare the lying and exploratory behavior of cows in the 24 h before calving and a previous day. Seventy-two Holstein dairy heifers and cows (n = 36 nulliparous and n = 36 primiparous and multiparous combined) were housed in a covered bedded-pack barn (167.4 m2) with free access to 2.1 ha of pasture. The composition of the group was dynamic, because cows were moved in weekly at 19 ± 6 d [mean ± standard deviation (SD)] before their calving date, and were removed immediately after calving. To facilitate data collection, we divided the environment into 9 sections, including the barn (section 1; 167.4 m2), 7 sections of open pasture (sections 2 to 8; 2,402 ± 60 m2), and 1 section of pasture surrounded by natural forage cover (section 9; 3,593 m2). We then collapsed these 9 sections into 3 distinct areas for further analysis: the barn, open pasture, and natural forage cover. Animals were fitted with accelerometers to measure lying time, lying bout duration, lying bouts, and steps for the 24 h before calving (calving day) and a similar 24 h period 4 to 11 d (median = 7) before calving (baseline day). We included parity (nulliparous vs. primiparous and multiparous) and heat stress [no heat stress = temperature-humidity index (THI) ≤68 vs. heat stress = THI >68 and ≤79] in all analyses; we included time of day and group composition as additional factors that may have affected calving location. We determined exploratory behavior using 10 min instantaneous scan sampling collected from video. At each scan, we recorded the section (1 to 9) the cow or heifer was located in, and then calculated the minimum number of sections that could be crossed between successive scans. Of the total sample, 39% calved in the barn, 26% calved in the open pasture, and 35% calved in the area with natural forage cover. Nulliparous heifers and those calving when heat stress was low (THI ≤68) selected the area with natural forage cover more frequently than the barn. On the calving day, cows spent more time lying down with more short bouts of lying, and crossed more sections compared with the baseline day. Steps were affected by an interactive effect of day, parity, and heat stress; nulliparous heifers took more steps on the calving day during conditions of heat stress compared with no heat stress. Results indicate that cows and heifers had different preferences for their environment at calving, and when provided access to pasture, both changed their lying and exploratory behavior on the day of calving compared with a previous day.


Assuntos
Comportamento Animal , Bovinos/fisiologia , Comportamento Exploratório , Animais , Indústria de Laticínios , Feminino , Resposta ao Choque Térmico , Abrigo para Animais , Umidade , Lactação , Paridade , Gravidez , Temperatura
20.
J Dairy Sci ; 103(6): 5759-5772, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32331875

RESUMO

The objective of this review was to describe recent changes and expected developments in housing systems for dairy cows. These new developments should create an appropriate production environment for modern high-producing dairy cows and stimulate dairy farming-related developments in management, agro-technology, and equipment. Increased labor efficiency has been an important driver of the change from tie-stall barns to cubicle barns (also known as freestall barns). In future housing systems, the natural behavior of cows, climate control, emissions of ammonia and greenhouse gases, reuse of waste, manure quality, the aesthetics of buildings in the landscape, and capital efficiency are becoming increasingly important elements. To address future requirements, new concepts beyond cubicle barns must be developed. Freewalk housing systems; that is, loose housing systems without cubicles, would meet some of these future demands. These systems operate with composting bedding material or artificial permeable floors as lying and walking areas. However, these barns are still in development. Combinations of cubicle and freewalk housing systems, together with other techniques being developed, might become a major future housing system. Other techniques and systems that are being explored according to sustainability criteria include the multi-climate shed, the CowToilet (Hanskamp AgroTech, Doetinchem, the Netherlands) to separate feces and urine, and multifunctional buildings. These buildings and techniques can be part of land-based or, less commonly, city-based farming systems, such as floating farms.


Assuntos
Bem-Estar do Animal , Bovinos/fisiologia , Abrigo para Animais/tendências , Animais , Doenças dos Bovinos/prevenção & controle , Indústria de Laticínios/métodos , Feminino
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