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1.
Sci Rep ; 14(1): 8872, 2024 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632328

RESUMEN

Play behaviour can act as an indicator of positive animal welfare. Previous attempts to predict play behaviour in farmed calves are limited because of the classification methods used, which lead to overestimation, and the short time periods that calves are observed. The study aimed to automatically classify and quantify play behaviour in farmed calves using location data from ultra-wide band sensors and to investigate factors associated with play behaviour. Location data were collected from 46 calves in three cohorts for a period of 18 weeks. Behavioural observations from video footage were merged with location data to obtain a total of 101.36 h of labelled data. An AdaBoost ensemble learning algorithm was implemented to classify play behaviour. To account for overestimation, generally seen in low-prevalence behaviours, an adjusted count technique was applied to the outputs of the classifier. Two generalized linear mixed models were fitted to investigate factors (e.g. age, health) associated with duration of play and number of play instances per day. Our algorithm identified play behaviour with > 94% accuracy when evaluated on the test set with no animals used for training, and 16% overestimation, which was computed based on the predicted number of samples of play versus the number of samples labelled as play on the test set. The instances and duration of play behaviour per day significantly decreased with age and sickness, whilst play behaviour significantly increased during and after weaning. The instances of play also significantly decreased as mean temperature increased. We suggest that the quantification method that we used could be used to detect and monitor other low prevalence behaviours (e.g. social grooming) from location data, including indicators of positive welfare.


Asunto(s)
Bienestar del Animal , Estado de Salud , Bovinos , Animales , Destete , Granjas , Algoritmos , Conducta Animal
2.
Animal ; 18(4): 101124, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38547554

RESUMEN

Globally, farmers are being increasingly encouraged to use technologies. Consequently, veterinarians often use farm data and technologies to provide farmers with advice. Yet very few studies have sought to understand veterinarians' perceptions of data and technologies on farms. The aim of this study was to understand veterinarians' experiences and opinions on data and technology on beef and dairy farms. An online qualitative survey was conducted with a convenience sample of 36 and 24 veterinarians from the United Kingdom and Ireland, respectively. The data were analysed using reflexive thematic analysis to generate four themes: (1) Improving veterinary advice through data; (2) Ensuring stock person skills are retained; (3) Longevity of technology; and (4) Solving social problems on farms. We show that technologies and data can make veterinarians feel more confident in the advice they give to farmers. However, the quality and quantity of data collected on cattle farms were highly variable. Furthermore, veterinarians were concerned that farmers can become over-reliant on technologies by not using their stockperson skills. As herd sizes increase, technologies can help to improve working conditions on farms with multiple employees of various skillsets. Veterinarians would like innovations that can help them to demonstrate their competence, influence farmers' behaviour, and ensure sustainability of the beef and dairy industries.


Asunto(s)
Veterinarios , Humanos , Bovinos , Animales , Granjas , Agricultores , Encuestas y Cuestionarios , Industria Lechera , Tecnología
3.
J Dairy Sci ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38490555

RESUMEN

For successful development and adoption of technology on dairy farms, farmers need to be included in the innovation process. However, the design of agricultural technologies usually takes a top-down approach with little involvement of end-users at the early stages. Living Labs offer a methodology that involve end-users throughout the development process and emphasize the importance of understanding users' needs. Currently, exploration of dairy farmers' needs of technologies has been limited to specific types of technology (e.g., smartphone apps) and adult cattle. The aim of this study was to use a Living Lab approach to identify dairy farmers' needs of data and technologies to improve herd health and inform innovation development. Eighteen focus groups were conducted with, in total, 80 dairy farmers from Belgium, Ireland, the Netherlands, Norway, Sweden, and the UK. Data were analyzed using Template Analysis and 6 themes were generated which represented the fundamental needs of autonomy, comfort, competence, community and relatedness, purpose, and security. Farmers favored technologies that provided them with convenience, facilitated their knowledge and understanding of problems on farm, and allowed them to be self-reliant. Issues with data sharing and accessibility, and usability of software were barriers to technology use. Furthermore, farmers were facing problems around recruitment and management of labor and needed ways to reduce stress. Controlling aspects of the barn environment, such as air quality, hygiene, and stocking density, was a particular concern in relation to youngstock management. In conclusion, the findings suggest that developers of farm technologies may want to include farmers in the design process to ensure a positive user experience and improve accessibility. The needs identified in this study can be used as a framework when designing farm technologies to strengthen need satisfaction and reduce any potential harm toward needs.

4.
Prev Vet Med ; 220: 106030, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37806078

RESUMEN

Appropriate management decisions are key for sustainable and profitable beef and dairy farming. Data-driven technologies aim to provide information which can improve farmers' decision-making practices. However, data-driven technologies have resulted in the emergence of a "data divide", in which there is a gap between the generation and use of data. Our study aims to further understand the data divide by drawing on social practice theory to recognise the emergence, linkages, and reproduction of youngstock data practices on cattle farms in the UK. Eight focus groups with fifteen beef and nineteen dairy farmers were completed. The topics of discussion included data use, technology use, disease management in youngstock, and future goals for their farm. The transcribed data were analysed using reflexive thematic analysis with a social practice lens. Social practice theory uses practices as the unit of analysis, rather than focusing on individual behaviours. Practices are formed of three elements: meaning (e.g., beliefs), materials (e.g., objects), and competencies (e.g., skills) and are connected in time and space. We conceptualised the data divide as a disconnection of data collection practices and data use and interpretation practices. Consequently, we were able to generate five themes that represent these breaks in connection.Our findings suggest that a data divide exists because of meanings that de-stabilise practices, tensions in farmers' competencies to perform practices, spatial and temporal disconnects, and lack of forms of feedback on data practices. The data preparation practice, where farmers had to merge different data sources or type up handwritten data, had negative meanings attached to it and was therefore sometimes not performed. Farmers tended to associate data and technology practices with larger dairy farms, which could restrict beef and small-scale dairy farms from performing these practices. Some farmers suggested that they lacked the skills to use technologies and struggled to transform their data into meaningful outputs. Data preparation and data use and interpretation practices were often tied to an office space because of the required infrastructure, but farmers preferred to spend time outdoors and with their animals. There appeared to be no normalisation of what data should be collected or what data should be analysed, which made it difficult for farmers to benchmark their progress. Some farmers did not have access to discussion groups or veterinarians who were interested in data and therefore could not get feedback on their data practices.These results suggest that the data divide exists because of three types of disconnect: a disconnect between elements within a practice because of tensions in competencies or negative meanings to perform a practice; a disconnect between practices because of temporal or spatial differences; and a break in the reproduction of practices because of lack of feedback on their practices. Data use on farms can be improved through transformation of practices by ensuring farmers have input in the design of technologies so that they align with their values and competencies.


Asunto(s)
Crianza de Animales Domésticos , Agricultores , Bovinos , Animales , Humanos , Crianza de Animales Domésticos/métodos , Industria Lechera/métodos , Granjas , Reino Unido
5.
Dig Liver Dis ; 35(10): 675-87, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14620614

RESUMEN

This article reviews the current situation regarding research towards an effective human vaccine against Helicobacter pylori, with particular emphasis on developments in the new millennium. The mechanism(s) by which immunisation of mice can affect helicobacter colonisation of mice remains a mystery, but may be related to immune mediated environmental changes. In particular, it is proposed that severe gastritis and T-cell mediated changes in mucin production can significantly impact upon H. pylori colonisation. Despite the potential influence of environmental factors, significant progress towards a truly effective vaccine may depend upon the induction of specific immune targeting of this pathogen. This would probably be best achieved by the generation of an appropriate antibody response, something which has not yet been accomplished. An overview of previous and current H. pylori vaccine clinical trials is also presented.


Asunto(s)
Vacunas Bacterianas , Infecciones por Helicobacter/prevención & control , Helicobacter pylori/inmunología , Animales , Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Mucosa Gástrica/microbiología , Gastritis/microbiología , Humanos , Lipopolisacáridos/metabolismo , Ratones , Moco/microbiología , Úlcera Péptica/microbiología , Linfocitos T Colaboradores-Inductores/inmunología
6.
Infect Immun ; 67(9): 4713-9, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10456921

RESUMEN

A total of seven clones producing both new and previously described Helicobacter pylori proteins were isolated from a library of H. pylori genomic DNA. The screening approach by which these proteins were detected relied on the use of antisera raised in mice vaccinated with Helicobacter felis sonicate plus cholera toxin, a regimen which protects mice from H. pylori challenge. This strategy was designed to maximize the possibility of obtaining antigens which might be capable of conferring protection from H. pylori infection. Two of the clones were shown to encode the urease enzyme and the heat shock protein HspB, which have already been identified as protective antigens. The other five clones were sequenced, protein coding regions were deduced, and these sequences were amplified by PCR for incorporation into Escherichia coli expression vectors. The proteins produced from these expression systems were purified to allow testing for protective efficacy in an H. pylori mouse model. All five proteins were able to facilitate the clearance of a challenge with H. pylori, as judged by an assay of gastric urease activity and light microscopy on stomach sections. These results clearly indicate that the screening strategy has successfully identified candidate vaccine antigens.


Asunto(s)
Antígenos Bacterianos/genética , Helicobacter pylori/genética , Animales , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/aislamiento & purificación , Secuencia de Bases , ADN Bacteriano , Expresión Génica , Genoma Bacteriano , Biblioteca Genómica , Infecciones por Helicobacter/prevención & control , Helicobacter pylori/inmunología , Ratones , Datos de Secuencia Molecular , Recombinación Genética , Análisis de Secuencia de ADN , Ureasa/genética
7.
Infect Immun ; 65(11): 4668-74, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9353048

RESUMEN

The efficacy of an orogastric vaccine comprised of purified Helicobacter pylori catalase plus the mucosal adjuvant cholera toxin (CT) was examined with both the Helicobacter felis and H. pylori mouse models with BALB/c mice. Native H. pylori catalase (200 microg) plus CT was initially used as a vaccine antigen in the H. felis mouse model and protected 80% (8 of 10) of the challenged animals, while all control animals were infected (20 of 20). In a follow-up experiment, recombinant H. pylori catalase plus CT was used for immunization, and groups of mice were challenged with the Sydney strain of H. pylori. Immunization with recombinant catalase protected a significant proportion (9 of 10) of the mice from H. pylori challenge, indicating that this enzyme should be considered as a candidate for a future vaccine. This study provides the first available data on the efficacy of protective immunization with the new Sydney strain of H. pylori in a mouse model. These data also provide indirect evidence that proteins which are normally intracellular, such as catalase, may be present on the surface of H. pylori and thus may provide targets for immunization.


Asunto(s)
Antígenos Bacterianos/inmunología , Vacunas Bacterianas/inmunología , Catalasa/inmunología , Helicobacter pylori/inmunología , Animales , Anticuerpos Antibacterianos/análisis , Catalasa/aislamiento & purificación , Estabilidad de Enzimas , Femenino , Ratones , Ratones Endogámicos BALB C , Vacunación
8.
J Bacteriol ; 176(9): 2663-9, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8169216

RESUMEN

The recombinant plasmid pJIR318 contains a fragment of the Dichelobacter nodosus genome which is associated with virulence. Sequence analysis of the pJIR318 insert has shown that it contains four vap (virulence-associated protein) genes which are homologous to open reading frames found on the Escherichia coli F plasmid and the Neisseria gonorrhoeae cryptic plasmid (M. E. Katz, R. A. Strugnell, and J. I. Rood, Infect. and Immun. 60:4586-4592, 1992). The plasmid pJIR318 hybridizes to three regions of the D. nodosus genome, each of which has now been isolated. Regions 1 and 3 were found to be adjacent in the genome of D. nodosus A198, and the order of the vap genes in vap regions 1 and 2 were shown to be identical. Partial sequence analysis and Southern blot analysis of the vap regions showed that the three regions probably arose by a duplication event(s) followed by insertions and/or deletions. A recombinant plasmid, pJIR749, was isolated from a library of a benign D. nodosus strain, 305. This plasmid contained sequences from both ends of vap region 2. Analysis of pJIR749 showed that the sequences on either side of vap region 2 were separated by 324 bp in the genome of benign strain 305 and that the orientations of the sequences were different. It is clear that a simple insertion or deletion event did not generate the benign and virulent strains studied. A model which describes the evolution of the duplicated vap regions in D. nodosus A198 is presented.


Asunto(s)
Bacterias Anaerobias/genética , Bacterias Anaerobias/patogenicidad , Proteínas Bacterianas/genética , Proteínas de Unión al ADN , Genes Bacterianos/genética , Familia de Multigenes , Factores de Virulencia , Secuencia de Bases , Clonación Molecular , Genoma Bacteriano , Glicoproteínas de Membrana/genética , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico , Virulencia/genética
10.
Aust Vet J ; 68(10): 317-9, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1755781

RESUMEN

Sheep were immunised with Corynebacterium pseudotuberculosis vaccines prepared from cell-free toxoid or from toxoid with formalin-killed cells of C pseudotuberculosis added. Resistance of sheep to infection was tested 6 months after immunisation by inoculation with caseous lymphadenitis pus. The outcome was assessed 3 months later by slaughter and inspection of the sheep for lesions of caseous lymphadenitis. immunised sheep were adequately protected against infection as shown by a significant reduction in the number of sheep exhibiting lesions compared with control sheep, and by fewer abscesses in affected vaccinated sheep than in affected control sheep. The protective potency of the vaccines was not improved by the inclusion of cells of C pseudotuberculosis.


Asunto(s)
Vacunas Bacterianas , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/inmunología , Linfadenitis/veterinaria , Enfermedades de las Ovejas/prevención & control , Animales , Vacunas Bacterianas/normas , Infecciones por Corynebacterium/prevención & control , Linfadenitis/prevención & control , Masculino , Distribución Aleatoria , Ovinos , Toxinas Biológicas/inmunología , Toxinas Biológicas/normas , Toxoides/inmunología , Toxoides/normas , Vacunación/veterinaria
11.
Aust Vet J ; 68(10): 320-1, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1755782

RESUMEN

Sheep were immunised with Corynebacterium pseudotuberculosis toxoid formulated as a monocomponent vaccine with aluminium adjuvant or in combination with 5 clostridial antigens, and also in the combined form with sodium selenate. Immunised and control sheep were experimentally infected 16 days after vaccination and slaughtered and inspected after a further 3 months to determine their resistance to infection. All 3 vaccines afforded an equal and high level of protection; 91% of vaccinated sheep exhibiting no lesions of caseous lymphadenitis compared with 51.5% affected sheep in the control group. Average lesion counts were 1.2 per affected vaccinated sheep and 4.5 per affected control sheep. Antitoxin responses to the clostridial toxoids incorporated in the combined vaccines were not affected by inclusion of the C pseudotuberculosis toxoid or the sodium selenate.


Asunto(s)
Vacunas Bacterianas , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/inmunología , Linfadenitis/veterinaria , Enfermedades de las Ovejas/prevención & control , Animales , Anticuerpos Antibacterianos/biosíntesis , Clostridium/inmunología , Infecciones por Corynebacterium/prevención & control , Linfadenitis/prevención & control , Masculino , Ovinos , Toxoides/inmunología , Vacunación/veterinaria
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