ABSTRACT
Federal regulations and policies require institutions to establish procedures for ongoing IACUC oversight of approved animal care and use program activities including animal procedures. To fulfill these requirements, research institutions implement postapproval monitoring (PAM) programs designed to assure compliance in animal activities. Although several references commenting on the requirement to conduct PAM are available, few publications discuss actual best practices for accomplishing PAM. Here we use information collected through a survey of large academic research institutions to identify common practices for conducting PAM reviews. Many similarities and differences exist between institutions, which may or may not influence the overall quality of an institution's PAM program.
Subject(s)
Animal Care Committees/legislation & jurisprudence , Animal Husbandry/legislation & jurisprudence , Animal Welfare/legislation & jurisprudence , Biomedical Research/legislation & jurisprudence , Housing, Animal/legislation & jurisprudence , Animal Husbandry/standards , Animals , Animals, Laboratory , Housing, Animal/standardsABSTRACT
A number of studies have shown widespread public concern over housing animals in ways that restrict their ability to move freely. Dairy cows housed in tie stall barns are tethered continuously or for part of the day, but no study has assessed public support for this type of housing system. We report two experiments assessing public perceptions of tie stall housing for dairy cattle using a hypothetical referenda format. In Experiment 1, 65% of participants (n = 430) said they would support a ban on tie stalls. The probability of supporting a ban increased as the duration of time that cows were tethered increased. In Experiment 2, information about possible economic consequences was included. Relatively fewer (55%) participants (n = 372) indicated they would support a ban. Supporters of a ban were willing to pay an average dairy product price premium of 68% to see the ban enacted. Indirect measures of support indicated socially desirable responding was greater in Experiment 2 where the economic impacts of voting behavior were made explicit. In both studies, women and liberals were more likely to support a ban. The majority of participants in Experiment 1 (51%) and Experiment 2 (57%) said they had never heard or read anything about tie stalls before participating in our survey. We conclude that current knowledge of the use of tie stalls is low, but if this situation were to change there may be considerable public concern about the use of this housing method.
Subject(s)
Animal Husbandry/statistics & numerical data , Animal Welfare/standards , Dairying , Housing, Animal/legislation & jurisprudence , Housing, Animal/standards , Public Opinion , Adult , Animals , Cattle , Child , Female , Humans , Male , Surveys and Questionnaires , United StatesABSTRACT
Due to welfare concerns and legal restrictions in certain countries, alternatives to wire net floors must be developed in rabbit husbandries. Also, there is a difference in regulations in Europe for laboratory rabbits vs. rabbits bred and kept for meat production. While there are regulations concerning floor design of enclosures for rabbits bred for meat production in many European countries, the European Directive 2010/63 lacks regulations for rabbits used for scientific purposes. This study compares two floors, which meet the Austrian legal requirements for growing rabbits intended for consumption as well as the requirements for laboratory rabbits. The dual use of rabbits bred for meat production and applicable for scientific purposes would avoid the problem of surplus animals of specialized producers for laboratory rabbits. A noryl floor with 12â¯mm circular holes was compared to a 10â¯mm slatted plastic floor. Parameters were soiling of cages and animals, parasitic burden, clinical health, and losses using objective scoring. Soiling of cages and animals and coccidial oocytes were significantly higher on the floors with circular holes. Obvious signs of disease showed a non-significant trend to be more frequent in the group with circular holes. This was linked with significantly higher losses. In conclusion, our study clearly shows that the floor with circular hole design cannot be endorsed, although it meets legal requirements. The slatted floor type can be cautiously recommended; however, to assure animal welfare in laboratory rabbits, legal authorities in Europe should take on the responsibility of regulating floor design in this sector.
Subject(s)
Animal Husbandry , Animal Welfare , Floors and Floorcoverings , Housing, Animal , Rabbits/physiology , Animals , Animals, Laboratory/physiology , Coccidiosis/parasitology , Coccidiosis/veterinary , Feces/parasitology , Floors and Floorcoverings/classification , Floors and Floorcoverings/legislation & jurisprudence , Housing, Animal/legislation & jurisprudence , Rabbits/parasitologySubject(s)
Behavior, Animal , Housing, Animal , Swine/psychology , Animal Welfare , Animals , Housing, Animal/legislation & jurisprudence , Male , Netherlands , WeaningABSTRACT
Proposition 2, which requires that egg-laying hens be confined only in ways that allow these animals to lie down, stand up, fully extend their limbs and turn around freely, was passed by the voters of California in 2008. These new housing requirements were introduced in the USA and European Union without considering the potential impact of changes in layer hen housing on the health of poultry workers in the new facilities. Particles were collected from ambient air inside a large layer hen complex featuring separate barns with conventional battery caging, enriched caging, or 'free range' (aviary) housing during winter, spring, and summer seasons over one year. Toxicity of the particles was evaluated by analysis of inflammatory cell influx into lung lavage fluid after intratracheal instillation into mice. Capacity of the particles to elicit oxidative stress was evaluated using a macrophage cell line engineered with a reporter gene sensitive to nuclear factor κB activation. We observed similar pro-inflammatory and pro-oxidant effects of the particles collected from different types of barns and over different seasons, suggesting that standard industrial hygiene techniques for evaluating respirable particles in ambient air can adequately monitor worker risk. Based on particle concentrations found in ambient air in the barns, we can rank the facilities for worker exposure to particles as conventional caging (now banned) approximately equal to enriched caging (permitted under Proposition 2). Aviary housing is associated with increased exposure of workers to particulate matter and, therefore, to greater risk of allergic reactions and/or decreased respiratory function.
Subject(s)
Air Pollutants, Occupational/toxicity , Chickens , Housing, Animal , Lung/drug effects , Particulate Matter/toxicity , Respiratory Mucosa/drug effects , Animal Husbandry , Animals , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/immunology , California , Cell Line , Endotoxins/chemistry , Endotoxins/toxicity , Housing, Animal/legislation & jurisprudence , Housing, Animal/standards , Humans , Inhalation Exposure/adverse effects , Lung/immunology , Macrophages, Alveolar/drug effects , Macrophages, Alveolar/immunology , Male , Mice, Inbred BALB C , NF-kappa B/agonists , NF-kappa B/metabolism , Occupational Exposure/adverse effects , Oxidative Stress/drug effects , Respiratory Mucosa/immunology , Seasons , Toxicity Tests, Acute , WorkforceABSTRACT
It is controversially discussed whether the stocking densities set by the EU Directive 2007/43/EC allow a species-appropriate housing of broiler chickens. To calculate the exact area broilers occupy due to their physical size and shape, planimetric measurements using a colour-contrast method were carried out. In total, 1949 photographs of standing and 1482 of squatting chickens, taken from a top view, were analysed. A computer program counted the pixels representing the previously weighed animal in the photograph and calculated the animal area. The average area covered by chickens with 400â g live weight was 116.64±13.12â cm(2) in a standing and 138.61±12.92â cm(2) in a squatting position. These areas increased linearly as a function of live weight to 452.57±58.89â cm(2) (R(2)=0.90 standing) and 513.54±42.70â cm(2) (R(2)=0.82 squatting) at the end of the study (3200â g live weight). Squatting chickens occupied more space compared with a standing position in most of the tested weight classes (P<0.05). Depending on target weights, stocking densities and body positions, broilers occupied 48.5-77.7 per cent of 1 m(2) Thus, from a physical point of view, simultaneous resting is possible at any stocking density provided by the EU Directive and at common target weights.
Subject(s)
Floors and Floorcoverings/statistics & numerical data , Housing, Animal/legislation & jurisprudence , Housing, Animal/statistics & numerical data , Animals , Body Weight , Chickens , European Union , PostureABSTRACT
To limit tail biting incidence, most pig producers in Europe tail dock their piglets. This is despite EU Council Directive 2008/120/EC banning routine tail docking and allowing it only as a last resort. The paper aims to understand what it takes to fulfil the intentions of the Directive by examining economic results of four management and housing scenarios, and by discussing their consequences for animal welfare in the light of legal and ethical considerations. The four scenarios compared are: 'Standard Docked', a conventional housing scenario with tail docking meeting the recommendations for Danish production (0.7 m2/pig); 'Standard Undocked', which is the same as 'Standard Docked' but with no tail docking, 'Efficient Undocked' and 'Enhanced Undocked', which have increased solid floor area (0.9 and 1.0 m2/pig, respectively) provision of loose manipulable materials (100 and 200 g/straw per pig per day) and no tail docking. A decision tree model based on data from Danish and Finnish pig production suggests that Standard Docked provides the highest economic gross margin with the least tail biting. Given our assumptions, Enhanced Undocked is the least economic, although Efficient Undocked is better economically and both result in a lower incidence of tail biting than Standard Undocked but higher than Standard Docked. For a pig, being bitten is worse for welfare (repeated pain, risk of infections) than being docked, but to compare welfare consequences at a farm level means considering the number of affected pigs. Because of the high levels of biting in Standard Undocked, it has on average inferior welfare to Standard Docked, whereas the comparison of Standard Docked and Enhanced (or Efficient) Undocked is more difficult. In Enhanced (or Efficient) Undocked, more pigs than in Standard Docked suffer from being tail bitten, whereas all the pigs avoid the acute pain of docking endured by the pigs in Standard Docked. We illustrate and discuss this ethical balance using numbers derived from the above-mentioned data. We discuss our results in the light of the EU Directive and its adoption and enforcement by Member States. Widespread use of tail docking seems to be accepted, mainly because the alternative steps that producers are required to take before resorting to it are not specified in detail. By tail docking, producers are acting in their own best interests. We suggest that for the practice of tail docking to be terminated in a way that benefits animal welfare, changes in the way pigs are housed and managed may first be required.
Subject(s)
Animal Welfare/standards , European Union , Housing, Animal/legislation & jurisprudence , Swine , Animal Welfare/legislation & jurisprudence , Animals , Bites and Stings , Europe , Housing, Animal/standards , IncidenceABSTRACT
Effective management and an appropriate environment are essential for dairy cattle health and welfare. Codes of practice provide dairy producers with best practice guidance for the care and handling of their cattle. New Canadian recommendations have been established for the dairy industry. The objectives of this study were to develop an on-farm assessment tool that helps producers assess how well they are meeting their code of practice and that identifies management and environment modifications that could improve dairy cow comfort on their farms. The assessment tool addressed critical areas of dairy cow comfort, including accommodation and housing (stall design, space allowance, stall management, pen management, milking parlor, and transfer alleys), feed and water (body condition scoring, nutrition), and health and welfare (lameness, claw health, and hoof-trimming). Targets of good practices were identified from the requirements and recommendations of the code of practice. Each farm received a score for each target, ranging from 0 (target not reached) to 100 (target reached). One hundred tiestall and 110 freestall farms were surveyed in 3 provinces of Canada (Quebec, Ontario, and Alberta). The duration of the assessment, in 2 visits lasting, on average, 8 and 9h (range between freestall and tiestall farms) and 4 and 4.1h, was beyond the targeted 3 to 4h due mainly to the animal-based measures; strategies to reduce the duration of the assessment were discussed. Standard operating procedures were developed to ensure consistency in measuring and recording data. Periodical checks were conducted by trainers to ensure all 15 assessors remained above target agreement of weighted kappa ≥0.6. Average scores for all critical areas ranged from 25 to 89% for freestall farms and from 48 to 95% for tiestall farms. These scores need to be considered with caution when comparing farms because scores could not always be calculated the same way between housing systems. An evaluation report was provided and discussed with each producer, identifying strengths and areas for improvement that could benefit dairy cow comfort on their farms. The producers were convinced of the effectiveness of our tool for assessing cow comfort (freestall: 86%; tiestall: 95%) and in assisting them to make decisions for improvements (freestall: 83%; tiestall: 93%). Our cow comfort assessment tool served as background material for the Dairy Farmers of Canada animal care assessment program.
Subject(s)
Animal Welfare , Cattle/physiology , Dairying/methods , Housing, Animal/standards , Alberta , Animals , Female , Housing, Animal/legislation & jurisprudence , Ontario , QuebecABSTRACT
Changes made in the 8th edition of the Guide for the Care and Use of Laboratory Animals included new recommendations for the amount of space for breeding female mice. Adopting the new recommendations required, in essence, the elimination of trio breeding practices for all institutions. Both public opinion and published data did not readily support the new recommendations. In response, the National Jewish Health Institutional Animal Care and Use Committee established a program to directly compare the effects of breeding format on mouse pup survival and growth. Our study showed an overall parity between trio and pairwise breeding formats on the survival and growth of the litters, suggesting that the housing recommendations for breeding female mice as stated in the current Guide for the Care and Use of Laboratory Animals should be reconsidered.
Subject(s)
Breeding/methods , Housing, Animal/ethics , Animals , Autoimmunity , Body Weight , Breeding/legislation & jurisprudence , Female , Guidelines as Topic , Housing, Animal/legislation & jurisprudence , Lymphocytes/immunology , Lymphocytes/metabolism , Male , Mice , Mice, Transgenic , PregnancyABSTRACT
The objective of this study was to monitor establishment and development of gastro-intestinal helminth infections in chickens over two production years (PY) on a free-range farm in Lower Saxony, Germany. The data were collected between July 2010 and June 2011 (PY1) and July 2011 and January 2013 (PY2), respectively. During PY1, Lohmann Brown classic (LB classic, N = 450) was tested, while in PY2 two different genotypes (230 LB classic, 230 LB plus) were used. The hens were kept in two mobile stalls that were moved to a new position at regular intervals. In both PY1 and PY2, 20 individual faecal samples per stall were randomly collected at monthly intervals in order to calculate the number of internal parasite eggs per gram of faeces (EPG). At the end of the laying periods, approximately 10% (N = 42) or more than 50% (N = 265) of hens were subjected to post-mortem parasitological examinations in PY1 and PY2, respectively. No parasite eggs were found in the faecal samples during PY1, whereas almost all of the hens (97.6%) were infected with Heterakis gallinarum (36 worms/hen) at the end of the period. In PY2, nematode eggs in faeces were found from the third month onwards at a low level, increasing considerably towards the final three months. There was no significant difference between the two genotypes of brown hens neither for EPG (P = 0.456) or for overall prevalence (P = 0.177). Mortality rate ranged from 18.3 to 27.4% but did not differ significantly between genotypes or production years. Average worm burden was 207 worms/hen in PY2. The most prevalent species were H. gallinarum (98.5%) followed by Ascaridia galli (96.2%) and Capillaria spp. (86.1%). Furthermore, three Capillaria species, C. obsignata, C. bursata and C. caudinflata were differentiated. In conclusion chickens kept on free-range farms are exposed to high risks of nematode infections and have high mortality rates with no obvious link to parasite infections. Once the farm environment is contaminated with the nematode eggs, establishment and further spread of nematodes to the hens is a matter of time. This will latest be the case in the second production period, even if the hens are kept in a rotation system and in small herd sizes. This underlines the importance of nematode infections in all free-range systems.
Subject(s)
Animal Husbandry/methods , Chickens/parasitology , Helminthiasis, Animal/parasitology , Intestinal Diseases, Parasitic/veterinary , Poultry Diseases/parasitology , Animal Husbandry/legislation & jurisprudence , Animal Husbandry/trends , Animals , Body Weight , Chickens/classification , Chickens/genetics , Chickens/growth & development , Feces/parasitology , Female , Genotype , Germany/epidemiology , Helminthiasis, Animal/epidemiology , Housing, Animal/legislation & jurisprudence , Housing, Animal/standards , Housing, Animal/trends , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/parasitology , Longitudinal Studies , Parasite Egg Count/veterinary , Poultry Diseases/epidemiology , PrevalenceABSTRACT
Erysipelas was diagnosed in a free-range laying flock with a high mortality of up to 7% per day and a severe decrease in egg production to 45%. The disease had a short course and unusual clinical features for erysipelas, including swollen, lacrimating and encrusted eyes. Bacteriologically, trapped poultry red mites and affected animals were culture-positive for Erysipelothrix rhusiopathiae. Isolates from layers and mites were both serotype 1b. Histopathology revealed disseminated intravasal coagulopathy in conjunctival small vessels as the cause of the oedema of the eye adnexes. After treatment with penicillin, mortality and egg production returned to normal levels. Although erysipelas in laying hens is rarely reported, it can develop as an emerging disease in alternative rearing systems and should always be considered if mortality increases in an older flock, especially with a high infestation of poultry red mites.
Subject(s)
Chickens , Conjunctival Diseases/veterinary , Edema/veterinary , Erysipelas/veterinary , Poultry Diseases/epidemiology , Animals , Arachnid Vectors/microbiology , Conjunctival Diseases/microbiology , Disease Outbreaks/veterinary , Edema/microbiology , Erysipelas/complications , Erysipelas/epidemiology , Erysipelas/mortality , Erysipelothrix/isolation & purification , Female , Germany/epidemiology , Housing, Animal/legislation & jurisprudence , Housing, Animal/standards , Mites/microbiology , Oviposition , Poultry Diseases/microbiology , Poultry Diseases/mortalityABSTRACT
U.S. federal regulations and standards governing the care and use of research animals enacted in the mid- to late 1980s, while having positive effects on the welfare and quality of the animals, have resulted in dramatic increases in overall research costs. In addition to the expenses of housing and caring for animals according to the standards, establishing the requisite internal compliance bureaucracies has markedly driven up costs, in both institutional monetary expenditures and lost research effort. However, many institutions are increasing these costs even further through additional self-imposed regulatory burden, typically characterized by overly complex compliance organizations and unnecessary policies and procedures. We discuss the sources of this self-imposed burden and recommend strategies for avoiding it while preserving an appropriate focus on animal well-being and research success.
Subject(s)
Animal Experimentation/standards , Animal Welfare/standards , Research/economics , Academies and Institutes/economics , Academies and Institutes/standards , Animal Care Committees , Animal Experimentation/legislation & jurisprudence , Animal Testing Alternatives/economics , Animal Welfare/economics , Animal Welfare/legislation & jurisprudence , Animals , Animals, Laboratory , Conflict of Interest , Cost-Benefit Analysis , Costs and Cost Analysis , Forms and Records Control , Guideline Adherence , Guidelines as Topic , Housing, Animal/economics , Housing, Animal/legislation & jurisprudence , Housing, Animal/standards , Organizational Policy , Research/legislation & jurisprudence , Research/standardsABSTRACT
Since 1985, the US Animal Welfare Act and Public Health Service policy have required that researchers using nonhuman primates in biomedical and behavioral research develop a plan "for a physical environment adequate to promote the psychological well-being of primates." In pursuing this charge, housing attributes such as social companionship, opportunities to express species-typical behavior, suitable space for expanded locomotor activity, and nonstressful relationships with laboratory personnel are dimensions that have dominated the discussion. Regulators were careful not to direct a specific set of prescriptions (i.e., engineering standards) for the attainment of these goals, but to leave the design of the programs substantially up to "professional judgment" at the local level. Recently, however, the Institute of Medicine, in its path-finding 2011 report on the necessity of chimpanzee use in research, bypassed this flexible and contingent concept, and instead, required as a central precondition that chimpanzees be housed in "ethologically appropriate" environments. In so doing, obligations of ethical treatment of one great ape species were elevated above the needs of some research. The evolution and significance of this change are discussed.
Subject(s)
Animal Experimentation/ethics , Animal Welfare , Ethics, Research , Housing, Animal , Pan troglodytes , Animal Experimentation/history , Animal Welfare/history , Animal Welfare/legislation & jurisprudence , Animal Welfare/standards , Animal Welfare/trends , Animals , Behavior, Animal , Choice Behavior , History, 20th Century , History, 21st Century , Housing, Animal/history , Housing, Animal/legislation & jurisprudence , Housing, Animal/standards , Housing, Animal/trends , Humans , Judgment , National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division , Pan troglodytes/psychology , Personal Autonomy , United StatesABSTRACT
Apesar do recolhimento de cães em via pública, domicílios ou do acolhimento pelos Centros de Controle de Zoonoses ser uma prática adotada que não controla a população canina, é uma atividade considerada medida primária e complementar de controle de zoonoses. O excedente populacional canino, além de sua importância na cadeia de transmissão de diversas doenças, representa também problemas em decorrência das agressões, acidentes de trânsito e impactos ambientais. Considerando a falta de informações sobre a dinâmica do destino de cães em canis após a Lei Estadual número 12.916/08 (dispõe sobre o controle da reprodução de cães e dá providências correlatas), o presente trabalho objetivou analisar o destino dos cães recolhidos pela Prefeitura Municipal de Botucatu e transportados ao Canil Municipal e também os doados pela população, comparativamente antes e depois da implementação da Lei. Foram analisadas 4038 fichas de entrada de cães do Canil, as quais foram armazenadas no banco de dados gerados pela planilha EXCEL e analisados por meio de Censo. Antes da Lei, eram eutanasiados 2193 (70%) cães e após, 639 (69%), percentualmente os valores são similares, entretanto, há uma diferença de 1557 cães eutanasiados. Esta diferença pode ser explicada pelos cuidados médicos veterinários oferecidos aos cães recolhidos, após a Lei, para posterior adoção, uma vez que antes a única medida adotada era a eutanásia. Os resultados permitiram concluir que a Lei impôs mudanças nos procedimentos no Canil, principalmente a diminuição do número de eutanásias realizadas, consequentemente aumentou a permanência desses animais. Também os motivos predominantes para o recolhimento dos cães.
Despite the gathering of dogs on public streets, homes and by the Centers for Zoonoses Control is a practice adopted that does not control the dog population, it is an activity considered as primary and supplementary of the zoonoses control. The canine surplus population, besides the important role in the chain of transmission of various diseases, is also due to problems of aggressions, traffic accidents and environmental impacts. Considering the lack of information on the dynamics destination of dogs in kennels after the State Law number 12.916/08 (provides for the control of dog reproduction and gives related provisions), the present study aimed to analyze the destination of dogs gathered by the Municipality Botucatu and transported to the Municipal Kennel and also donated by the population comparison before and after the implementation of the Law. Were analyzed 4038 input records of the dogs of the kennel, which were stored in the database generated by EXCEL spreadsheet and analyzed through Census. Before the Law, were euthanized 2193 (70%) and after 639 dogs (69%), percentage terms values are similar, however, there is a difference of 1557 dogs euthanized. This difference can be explained by the veterinary medical care offered to dogs gathered after the Law, for subsequent adoption. Since before the only measure taken was euthanasia. The results concluded that the law imposes considerable changes in behaviors and procedures performed in the kennel, especially the decrease in the number of euthanized dogs and the adoption of more selective criteria for the gathering of dogs on public roads.
A pesar de la recogida de perros en las calles, domicilios y la acogida por el Centro de Control de Zoonosis no ser una práctica adoptada para controlar la población de perros, es una actividad que se considera medida primaria y complementaria para controlar las zoonosis. El exceso de población canina, y su importancia en la cadena transmisión de diversas enfermedades también representa problemas como consecuencia de las agresiones, accidentes de tránsito e impactos ambientales. Teniendo en cuenta la falta de información sobre la dinámica del destino de los perros en las perreras después de la Ley del Estado número 12.916/08 (que dispone sobre control de reproducción canina y disposiciones conexas), el presente estudio tuvo como objetivo analizar el destino de los perros de la Intendencia Municipal de Botucatu y transportados a la perrera Municipal, y también los donados por la población en comparación anterior y posterior a la implementación de la ley. Fueron analizadas 4038 fichas de entrada de perros en la perrera, las cuales se almacenaron en la base de datos generada en EXCEL y analizadas mediante Censo. Antes de la ley, fueron sacrificados 2193 (70%) perros y después de la ley, 639 (69%); los valores porcentuales son similares, sin embargo, hay una diferencia de 1.557 perros eutanasiados. Esta diferencia se explica por la atención médica veterinaria que se ofrece a los perros recogidos después de la ley para su posterior adopción, una vez que antes la única medida tomada era la eutanasia. Los resultados concluyeron que la ley impuso cambios en los procedimientos en la perrera, principalmente para reducir el número de perros eutanasiados, como consecuencia, se incrementó la permanencia de estos animales. También las razones predominantes para la recogida de los perros de las calles son los que tenían algún tipo de riesgo para la población.
Subject(s)
Animals , Dogs , Human-Animal Bond , Population Control/methods , Euthanasia, Animal/legislation & jurisprudence , Housing, Animal/legislation & jurisprudence , BrazilABSTRACT
Legal requirements on space and dimensions regarding furnished cages and alternative systems in laying hen husbandry are subject of constant discussion. Further knowledge about basic measures of the hens might help to come to reasonable results in the future. Digital images of Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB) laying hens, housed at the Lehr- und Forschungsgut Ruthe, University for Veterinary Medicine Hanover, Foundation, in Big Dutchman Eurovent laying hen cages, were made at three stages (19th, 36th and 58th week) of production. All hens had been taken out of their cages by night and set on a perch in a special cage used to photograph the hens frontally under controlled conditions. Body widths were calculated by a python application Cdisto.py0 2009 Andreas Briese) to mark and measure the body width in the digital images of a total of 156 hens. Mean body widths of 133.77 mm in Lohmann-LSL hens (SD = 9.71; N = 64; mean weight: 1.73 kg) and of 152.55 mm in Lohmann-LB hens (SD = 10.31; N = 92; mean weight: 1.93 kg) respectively were found. Even slight changes in body weights had no effect on the body width. Nonetheless the differences between both hybrids were always statistically significant (Mann-Whitney p < 0,001). Using these preliminary results on body width in a mathematical model simultanious feeding behaviour becomes only possible if the number of animals is reduced by 10.3% to 89.7% in LSL and by 21.3% to 78.7% in LB breeds in relation to a calculated maximum on base of the minimum space requirements for furnished cages in the EU-Dir 74/1999/EC.