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1.
BMC Pulm Med ; 19(1): 19, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30665395

RESUMO

BACKGROUND: RGM medium is an agar-based, selective culture medium designed for the isolation of nontuberculous mycobacteria (NTM) from the sputum of patients with cystic fibrosis (CF). We evaluated RGM medium for the detection of NTM in patients with CF (405 samples), bronchiectasis (323 samples) and other lung diseases necessitating lung transplantation (274 samples). METHODS: In total, 1002 respiratory samples from 676 patients were included in the study. Direct culture on RGM medium, with incubation at two temperatures (30 °C and 37 °C), was compared with conventional culture of decontaminated samples for acid-fast bacilli (AFB) using both a solid medium (Löwenstein-Jensen medium) and a liquid medium (the Mycobacterial Growth Indicator Tube; MGIT). RESULTS: For all three patient groups, significantly more isolates of NTM were recovered using RGM medium incubated at 30 °C than by any other method (sensitivity: 94.6% vs. 22.4% for conventional AFB culture; P < 0.0001). Significantly more isolates of Mycobacterium abscessus complex were isolated on RGM at 30 °C than by AFB culture (sensitivity: 96.1% vs. 58.8%; P < 0.0001). The recovery of Mycobacterium avium complex was also greater using RGM medium at 30 °C compared to AFB culture (sensitivity: 83% vs. 70.2%), although this difference was not statistically significant and a combination of methods was necessary for optimal recovery (P = 0.21). CONCLUSIONS: In the largest study of RGM medium to date, we reaffirm its utility for isolation of NTM from patients with CF. Furthermore; we show that it also provides an effective tool for culture of respiratory samples from patients with bronchiectasis and other lung diseases.


Assuntos
Bronquiectasia/microbiologia , Fibrose Cística/microbiologia , Doenças Pulmonares Intersticiais/microbiologia , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Micobactérias não Tuberculosas/isolamento & purificação , Doença Pulmonar Obstrutiva Crônica/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Meios de Cultura , Técnicas de Cultura , Feminino , Humanos , Pneumopatias/microbiologia , Transplante de Pulmão , Masculino , Pessoa de Meia-Idade , Mycobacterium abscessus/isolamento & purificação , Complexo Mycobacterium avium/isolamento & purificação , Infecção por Mycobacterium avium-intracellulare/diagnóstico , Sensibilidade e Especificidade , Escarro , Adulto Jovem
2.
Vet Rec ; 179(16): 412-413, 2016 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-27770094

RESUMO

Adopting the concept of One Welfare could help to improve animal welfare and human wellbeing worldwide, argue Rebeca García Pinillos, Michael Appleby, Xavier Manteca, Freda Scott-Park, Charles Smith and Antonio Velarde.


Assuntos
Bem-Estar do Animal/organização & administração , Comportamento Cooperativo , Saúde Global , Animais , Humanos
5.
Poult Sci ; 90(9): 2097-109, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21844278

RESUMO

The attributes of egg production that elicit values-based responses include the price and availability of eggs, environmental impacts, food safety or health concerns, and animal welfare. Different social groups have distinct interests regarding the sustainability of egg production that reflect these diverse values. Current scientifically based knowledge about how values and attitudes in these groups can be characterized is uneven and must be derived from studies conducted at varying times and using incomplete study methods. In general, some producer and consumer interests are translated through markets and are mediated by market mechanisms, whereas others are poorly reflected by economic behavior. An array of survey and focus group research has been performed to elicit consumer and activist beliefs about performance goals they would expect from an egg production system. These studies provide evidence that consumers' market behavior may be at odds with their ethical and political beliefs about performance goals.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas , Conservação dos Recursos Naturais/métodos , Comportamento do Consumidor , Ovos/normas , Bem-Estar do Animal/normas , Animais , Feminino , Responsabilidade Social
6.
Rev Sci Tech ; 28(2): 611-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20128471

RESUMO

The primary responsibility of veterinarians is to the animals in their care, so veterinary students need to be aware of important issues and factual information relevantto animal welfare. Veterinarians have tended to concentrate on physical aspects of welfare, but also need to take account of mental aspects (including pain) and naturalness. A crucial first step in animal welfare education is to encourage students to examine the interactions between welfare science, ethics and policy. Scientific measures of welfare include physiological, immunological, behavioural, disease and productivity. Welfare ethics includes consideration of different ethical theories and of professional ethics. Understanding of policy involves awareness of legislation, codes of practice and farm assurance programmes. As well as utilising their education in their clinical practice, veterinarians may expectto have an important role in influencing policy and standards in the wider world. It is recommended that animal welfare should be taught as a clearly defined academic subject within the curriculum.


Assuntos
Criação de Animais Domésticos/educação , Bem-Estar do Animal/ética , Educação em Veterinária , Abastecimento de Alimentos/normas , Criação de Animais Domésticos/normas , Bem-Estar do Animal/legislação & jurisprudência , Animais , Meio Ambiente , Humanos , Legislação Veterinária , Carne/normas , Dor/prevenção & controle , Dor/veterinária , Medicina Veterinária/normas
7.
Curr Top Microbiol Immunol ; 321: 151-68, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18727491

RESUMO

The ability to rapidly and efficiently recognize and eliminate pathogens while sparing normal self tissue is a hallmark of the mammalian immune system. When it fails, however, autoimmune disease results. The genetic and environmental factors that control the process of making such distinctions, not to mention the specific targeted tissues, are extraordinarily complex in the human population; only now are we characterizing the candidate genes responsible for these responses to pathogens. The examination of specific traits in murine models of disease has led to the identification of many of the candidate genes for human disease. The study of mouse mutations (both induced and spontaneous) has also greatly advanced our understanding of the immune responses and autoimmune disease. Here, we describe the use of classical mouse genetics to identify one gene centrally involved in the control of immune responses. Furthermore, although mutations in the orthologous human gene result in a virtually identical phenotype to that seen in the mouse, it is unlikely that studying the human disease populations alone would have successfully identified this gene. Thus, despite the complete sequencing of the human and mouse genomes, the examination of murine mutations remains a powerful and unbiased tool to connect genotype and phenotype.


Assuntos
Mapeamento Cromossômico , Fatores de Transcrição Forkhead/genética , Tolerância Imunológica/genética , Animais , Humanos , Mutação , Fenótipo , Linfócitos T/imunologia
8.
Rev Sci Tech ; 24(2): 625-38, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16358513

RESUMO

The welfare of animals is of interest to many people in most parts of the world. Concern about the way that animals are treated will depend on many factors, including socio-economic conditions, culture, religion and tradition. The World Organisation for Animal Health (OIE) is committed to ensuring that all animal welfare standards are science-based, but recognises that these other factors must also be taken into account. The International Coalition for Farm Animal Welfare (ICFAW) was formed to represent the interests of non-governmental animal welfare organisations from most corners of the globe and opinions, comment and information from these animal welfare organisations will play a part in the OIE decision-making process. In coming together for this purpose it was recognised that the views of the various member organisations of ICFAW vary depending on which part of the world they come from. The authors provide information about the situation in three continents: Africa, North America and Europe. This information includes details of relevant legislation, farming practices, and educational and campaign programmes developed by both animal welfare non-governmental organisations and governments. The authors also look to the future to see what issues may influence the way that farm animals are reared, transported and slaughtered.


Assuntos
Bem-Estar do Animal , Animais Domésticos , Legislação Veterinária/normas , Organizações/organização & administração , Organizações/normas , Animais , Agências Internacionais , Cooperação Internacional , Organizações/tendências , Meios de Transporte
9.
J Econ Entomol ; 97(2): 518-24, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15154476

RESUMO

The relative efficacy of an insecticide program and an insecticide plus mating disruption program using a sprayable pheromone formulation or a hand-applied pheromone dispenser was compared for control of the obliquebanded leafroller, Choristoneura rosaceana (Harris) at three commercial apple farms in a production area along the north shore of Lake Ontario, Canada, during 2000, 2001, and 2002. The average rate of disruption ranged from 50 to 80% in blocks of orchard treated with sprayable pheromone and from 84 to 98% in blocks treated with the hand-applied dispenser. The average proportion of shoots with larval feeding injury ranged from 0.002 to 0.09, 0.001 to 0.09, and 0.005 to 0.13 in the insecticide, insecticide plus sprayable pheromone, and insecticide plus hand-applied dispenser treatments, respectively, during the 3-yr study. The percentage of fruit with damage caused by spring, summer and overwintering larvae ranged from 0.03 to 0.06, 0.01 to 0.02, and 0.01 to 0.03 in the insecticide, insecticide plus sprayable pheromone, and insecticide plus hand-applied dispenser treatments, respectively. The addition of sex pheromone-mediated mating disruption to a conventional, insecticide-based program did not provide additional control of C. rosaceana feeding injury to shoots or fruit. The possible reasons for the failure of mating disruption to provide additional control are discussed.


Assuntos
Controle de Insetos/métodos , Inseticidas/administração & dosagem , Malus , Mariposas , Feromônios/administração & dosagem , Animais , Larva , Estações do Ano
10.
J Clin Pathol ; 56(7): 528-31, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12835299

RESUMO

AIMS: To compare the performance of a new chromogenic medium, Uriselect 4, with cystine lactose electrolyte deficient (CLED) agar and an established chromogenic agar, CPS ID 2 medium, for detection of urinary tract pathogens. METHODS: Using a semiquantitative culture method, 777 samples were inoculated on to the three test media in duplicate. All bacterial strains that yielded a potentially significant growth were observed for colony colour and identified using standard methods. RESULTS: Of the 777 samples tested, 589 urine samples yielded potentially significant growth of at least one strain. A total of 811 strains were isolated on at least one of the three media. A total of 168 urine samples yielded a mixture of at least two strains. Uriselect 4 medium showed the best sensitivity of the three media and only failed to recover 14 strains (1.7%). CPS ID 2 medium failed to recover 22 strains (2.7%). CLED medium showed the worst recovery and failed to recover 74 strains (9.1%). Both chromogenic media allowed for identification of Escherichia coli with a high degree of specificity (98% for Uriselect 4, 99.7% for CPS ID 2). Inclusion of a spot indole test increased the specificity of both chromogenic media to 100% for E coli. CONCLUSIONS: Uriselect 4 and CPS ID 2 were superior to CLED medium for the isolation of urinary tract pathogens mainly because of their ability to discriminate mixed cultures. Both chromogenic media were also useful for the preliminary identification of the most common urinary tract pathogens.


Assuntos
Bactérias/isolamento & purificação , Compostos Cromogênicos , Infecções Urinárias/diagnóstico , Ágar , Técnicas Bacteriológicas , Meios de Cultura , Humanos , Sensibilidade e Especificidade
11.
Br Poult Sci ; 43(4): 489-500, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12365505

RESUMO

1. A 3-year trial was carried out of cages for laying hens, occupying a full laying house. The main cage designs used were 5000 cm2 in area, 50 cm high at the rear and furnished with nests and perches. F cages had a front rollaway nest at the side, lined with artificial turf. FD cages also had a dust bath containing sand over the nest. H cages had two nest hollows at the side, one in front of the other. They were compared with conventional cages 2500 cm2 in area and 38 cm high at the rear. 2. Cages were stocked with from 4 to 8 ISA Brown hens per cage, resulting in varied allowances of area, feeder and perch per bird. No birds were beak trimmed. In F and FD cages two further treatments were applied: nests and dust baths were sometimes fitted with gates to exclude birds from dust baths in the morning and from both at night; elevated food troughs, with a lip 33 cm above the cage floor, were compared with standard troughs. 3. Management of the house was generally highly successful, with temperature control achieved by ventilation. Egg production was above breeders' standards and not significantly affected by cage design. More eggs per bird were collected when there were fewer birds per cage but food consumption also then tended to be higher. 4. The number of downgraded eggs was variable, with some tendency for more in furnished cages. Eggs laid in dust baths were often downgraded. Those laid at the back of the cage were frequently dirty because of accumulation of droppings. H nests were unsuccessful, with less than 50% of eggs laid in the nest hollows. However, up to 93% of eggs were laid in front rollaways, and few of these were downgraded. 5. Feather and foot damage were generally less in furnished than in conventional cages, greater where there were more birds per cage. With an elevated food trough there was less feather damage but more overgrowth of claws. In year 2, mortality was greater in cages with more birds. 6. Pre-laying behaviour was mostly settled in front rollaway nests. Dust baths were used more for pecking and scratching than for dust bathing. Comfort behaviour was more frequent in furnished cages than conventional, although still not frequent. Locomotion was strongly affected by number of birds per cage or by space per bird, being reduced by crowding. Most birds perched at night except in one treatment providing only 10.7 cm perch per bird. 7. Behaviour was more unrestricted and varied, and physical condition was better, in furnished than in conventional cages. However, egg production will cost more in furnished cages, partly because more eggs are downgraded. Dust baths must be fitted with gates that the birds cannot open from outside, but gates for nest boxes were found unnecessary. If a low perch is fitted it must be far enough from the back of the cage for birds to walk there. 8. Where there was less space per bird (more birds per cage) than the requirements in the 1999 European Commission Directive on laying hens, there were: fewer eggs per hen, but still above the breeders' target; lower food consumption; more feather and foot damage, but less than in conventional cages; higher mortality in one trial out of three; less freedom of movement. However, the results were still very good even with 8 birds per cage, and support the principle that furnished cages provide an acceptable way of protecting the welfare of laying hens.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Ingestão de Alimentos , Ovos/normas , Abrigo para Animais , Oviposição , Bem-Estar do Animal , Animais , Comportamento Animal , Desenho de Equipamento , Plumas/lesões , Feminino , Pisos e Cobertura de Pisos , Densidade Demográfica
12.
IEEE Nucl Sci Symp Conf Rec (1997) ; 49(1): 172-175, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26568676

RESUMO

We have developed a high-resolution, compact semiconductor camera for nuclear medicine applications. The modular unit has been used to obtain tomographic images of phantoms and mice. The system consists of a 64 x 64 CdZnTe detector array and a parallel-hole tungsten collimator mounted inside a 17 cm x 5.3 cm x 3.7 cm tungsten-aluminum housing. The detector is a 2.5 cm x 2.5 cm x 0.15 cm slab of CdZnTe connected to a 64 x 64 multiplexer readout via indium-bump bonding. The collimator is 7 mm thick, with a 0.38 mm pitch that matches the detector pixel pitch. We obtained a series of projections by rotating the object in front of the camera. The axis of rotation was vertical and about 1.5 cm away from the collimator face. Mouse holders were made out of acrylic plastic tubing to facilitate rotation and the administration of gas anesthetic. Acquisition times were varied from 60 sec to 90 sec per image for a total of 60 projections at an equal spacing of 6 degrees between projections. We present tomographic images of a line phantom and mouse bone scan and assess the properties of the system. The reconstructed images demonstrate spatial resolution on the order of 1-2 mm.

13.
J Immunol ; 167(11): 6312-20, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11714795

RESUMO

In the absence of the recently identified putative transcription factor scurfin, mice develop a lymphoproliferative disorder resulting in death by 3 wk of age from a pathology that resembles TGF-beta or CTLA-4 knockout mice. In this report, we characterize mice that overexpress the scurfin protein and demonstrate that these animals have a dramatically depressed immune system. Mice transgenic for the Foxp3 gene (which encodes the scurfin protein) have fewer T cells than their littermate controls, and those T cells that remain have poor proliferative and cytolytic responses and make little IL-2 after stimulation through the TCR. Although thymic development appears normal in these mice, peripheral lymphoid organs, particularly lymph nodes, are relatively acellular. In a separate transgenic line, forced expression of the gene specifically in the thymus can alter thymic development; however, this does not appear to affect peripheral T cells and is unable to prevent disease in mice lacking a functional Foxp3 gene, indicating that the scurfin protein acts on peripheral T cells. The data indicate a critical role for the Foxp3 gene product in the function of the immune system, with both the number and functionality of peripheral T cells under the aegis of the scurfin protein.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Ativação Linfocitária/genética , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Células Cultivadas , Proteínas de Ligação a DNA/fisiologia , Fatores de Transcrição Forkhead , Regulação da Expressão Gênica/imunologia , Histocitoquímica , Imunofenotipagem , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Teste de Cultura Mista de Linfócitos , Linfopenia/genética , Linfopenia/imunologia , Linfopenia/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Camundongos Transgênicos , Subpopulações de Linfócitos T/metabolismo , Timo/imunologia , Timo/metabolismo , Timo/patologia , Transgenes/imunologia
16.
Nat Genet ; 27(1): 18-20, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11137992

RESUMO

To determine whether human X-linked neonatal diabetes mellitus, enteropathy and endocrinopathy syndrome (IPEX; MIM 304930) is the genetic equivalent of the scurfy (sf) mouse, we sequenced the human ortholog (FOXP3) of the gene mutated in scurfy mice (Foxp3), in IPEX patients. We found four non-polymorphic mutations. Each mutation affects the forkhead/winged-helix domain of the scurfin protein, indicating that the mutations may disrupt critical DNA interactions.


Assuntos
Doenças dos Animais/genética , Proteínas de Ligação a DNA/genética , Diabetes Mellitus/congênito , Diabetes Mellitus/genética , Poliendocrinopatias Autoimunes/genética , Enteropatias Perdedoras de Proteínas/genética , Cromossomo X/genética , Sequência de Aminoácidos , Animais , Análise Mutacional de DNA , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Fatores de Transcrição Forkhead , Ligação Genética/genética , Humanos , Recém-Nascido , Camundongos , Camundongos Mutantes , Dados de Sequência Molecular , Mutação/genética , Alinhamento de Sequência , Síndrome
17.
Hosp Med ; 60(3): 183-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10476240

RESUMO

This article is an overview of nuclear cardiology for the busy clinician. We discuss the use of myocardial perfusion scans, radionuclide ventriculography, positron emission tomography scans and the interpretation of nuclear scan reports.


Assuntos
Isquemia Miocárdica/diagnóstico por imagem , Cardiotônicos , Humanos , Angiografia Cintilográfica , Ventriculografia com Radionuclídeos , Tecnécio , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão/instrumentação
18.
J Immunol ; 162(5): 2546-54, 1999 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10072494

RESUMO

Mice hemizygous (Xsf/Y) for the X-linked mutation scurfy (sf) develop a severe and rapidly fatal lymphoproliferative disease mediated by CD4+CD8- T lymphocytes. We have undertaken phenotypic and functional studies to more accurately identify the immunologic pathway(s) affected by this important mutation. Flow cytometric analyses of lymphoid cell populations reveal that scurfy syndrome is characterized by changes in several phenotypic parameters, including an increase in Mac-1+ cells and a decrease in B220+ cells, changes that may result from the production of extremely high levels of the cytokine granulocyte-macrophage CSF by scurfy T cells. Scurfy T cells also exhibit strong up-regulation of cell surface Ags indicative of in vivo activation, including CD69, CD25, CD80, and CD86. Both scurfy and normal T cells are responsive to two distinct signals provided by the TCR and by ligation of CD28; scurfy cells, however, are hyperresponsive to TCR ligation and exhibit a decreased requirement for costimulation through CD28 relative to normal controls. This hypersensitivity may result, in part, from increased costimulation through B7-1 and B7-2, whose expression is up-regulated on scurfy T cells. Although the specific defect leading to this hyperactivation has not been identified, we also demonstrate that scurfy T cells are less sensitive than normal controls to inhibitors of tyrosine kinases such as genistein and herbimycin A, and the immunosuppressant cyclosporin A. One interpretation of our data would suggest that the scurfy mutation results in a defect, which interferes with the normal down-regulation of T cell activation.


Assuntos
Imunoconjugados , Transtornos Linfoproliferativos/genética , Linfócitos T/imunologia , Abatacepte , Animais , Antígenos CD , Antígenos de Diferenciação/análise , Antígeno B7-1/análise , Benzoquinonas , Antígeno CTLA-4 , Ciclosporina/farmacologia , Feminino , Genisteína/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Lactamas Macrocíclicas , Antígenos Comuns de Leucócito/análise , Ativação Linfocitária , Transtornos Linfoproliferativos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Mutantes , Proteínas Nucleares/análise , Quinonas/farmacologia , Receptores de Antígenos de Linfócitos T/fisiologia , Rifabutina/análogos & derivados , Fatores de Transcrição/análise
19.
Anim Welf ; 8(4): 381-90, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-11933932

RESUMO

Attitudes to animal biotechnology are diverse, partly because people have different viewpoints and often do not recognize or acknowledge this to be so. First, people adopt different ethical approaches. If an opponent of genetic manipulation says 'I don't like the idea of altering animals' biology' and a proponent replies '...but it is useful', they are failing to communicate, because one is asking whether the action is right or wrong, whereas the other emphasizes the consequences. Another approach focuses on the person carrying out the action. Many people have hybrid views combining elements of these different approaches. Second, people's concepts of welfare vary, emphasizing animal minds, bodies or natures--or a combination of these. A proponent who argues that a particular genetic change will not cause suffering is unlikely to reassure an opponent who puts more emphasis on naturalness than on feelings or health. An improved dialogue, in which people attempt to understand one another's viewpoints, may enable common principles to be established and practical measures to be taken that enable more cooperation in attempts to improve both human and animal welfare.


Assuntos
Bem-Estar do Animal , Animais , Atitude , Biotecnologia , Comunicação , Análise Ética , Humanos
20.
Br Poult Sci ; 39(2): 186-90, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9649869

RESUMO

1. Three experiments were carried out with ISA Brown laying hens housed in individual cages with softwood perches of rectangular cross section fitted across the width of each cage, to investigate factors affecting the tendency of hens to lay their eggs from the perches and to use perches at other times. These factors were perch width and angle and method of perch introduction. 2. In experiment 1 there were 4 treatments. Perches were 38 or 60 mm wide; half of each width were flat and half were fixed at 8 degrees, parallel to the slope of the floor. In 2 similar trials (with 48 and 44 birds respectively, equally divided between treatments) birds were moved to experimental cages already fitted with perches. Birds with 38 mm, sloping perches laid less than one third of their eggs from the perch (31% and 9% in the two trials) while those with the other designs laid more than 80% from the perch. Narrow sloping perches were not otherwise aversive and there was no consistent variation between treatments in total time perching. 3. In experiment 2, 32 birds were allowed to start laying on the floor of the experimental cages then perches were introduced at 24 weeks with 8 birds on each of 4 treatments: 50 mm perches fixed flat and 38 mm perches fixed flat, and at 5 and 10 degrees respectively. Only 27% of eggs were laid from the perches with no variation between treatments either in this behaviour or in total time perching. 4. Experiment 3 provided 24 of the birds from experiment 2 with double-length perches to determine whether they showed preferences for the design features under consideration. Either half the perch length was flat and half sloping at 10 degrees or half was 38 and half 50 mm wide. Again a relatively low proportion of eggs was laid from the perches (18%) and birds showed no significant preference for different perch designs as indicated by either how much they perched or where they perched. 5. These results suggest that both perch design and the way pullets are introduced to perches influence the proportion of perch-laid eggs. They confirm that in some circumstances laying from perches can be a serious problem, but that in other circumstances incidence can be reduced to a manageable frequency. Perches may therefore be practical in commercial production without increasing the number of cracked eggs. The results are also likely to be applicable in cages with other facilities including nest boxes.


Assuntos
Galinhas , Abrigo para Animais , Oviposição , Animais , Comportamento Animal , Arquitetura de Instituições de Saúde , Feminino , Fatores de Tempo
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