Progress 09/15/05 to 09/14/09
Outputs
OUTPUTS: To develop realistic simulated models of animal movement that would be used to a. Identify the factors that influence the statistical measures used in animal studies to determine the effects of varying complex environments and social interactions; b. Determine best methods of analysis and sampling techniques to accurately describe movement and use of space by confined animals; and, c. Test the impact of future environmental interventions. 2. To validate, adjust and refine our simulated models of animal movement with data of real animals maintained under divers physical and social environments at: a. Varying density, group size and arena size and, b. Presence of barriers and resource location. PARTICIPANTS: The goal of this study is to develop a conceptual model of animal movement that will accurately reflect actual animal behavior in a complex and confined space; to determine best methods of analysis to adequately capture patterns of animal movement and use of space in confinement; and to establish the best and most efficient sampling techniques to conduct these studies. TARGET AUDIENCES: Once a valid conceptual model is obtained we will determine the best methods of analysis to adequately capture patterns of animal movement and use of space in confinement and the best and most efficient sampling techniques to conduct these studies. The innovative models of animal movement generated in this study will simulate realistic animal movement under diverse environmental conditions and ultimately can be used in evaluating commercial management practices relative to their effects on animal welfare, to scientifically determine minimal space requirements and optimal resource distribution to insure the health and welfare of domestic animals while maintaining high animal performance and productivity, and finally can be used to test the impact of future environmental interventions. PROJECT MODIFICATIONS: Test the impact of future environmental interventions. 2. To validate, adjust and refine our simulated models of animal movement with data of real animals maintained under divers physical and social environments at: a. Varying density, group size and arena size and, b. Presence of barriers and resource location.
Impacts
Most importantly, the development of a mathematical model of animal movement for confined animals, new methodology to calculate movement patterns, their complexity as measured by tortuosity (once developed and refined using our animal data), will be a powerful tool to evaluate commercial management practices relative to their effects on animal welfare (as measured by patterns of movements). We will be able to scientifically determine minimal space requirements and an optimal resource distribution to insure the health and welfare of domestic animals while maintaining high animal performance and productivity. In addition, the generated models of animal movement can be used to explore the potential consequences of future environmental interventions before they are implemented. The outcomes of this research go beyond the proposed poultry experiments as the new statistical methodology developed can be applied to any studies that involve observation of animal movement in confinement (such as areas of toxicology and neurology).
Publications
- 1. Mallapur, A., Estevez, I., Miller C. & Christman, M.C. (2007). Movement and use of the space in confinement; The effects of group size and pen size in broilers (Gallus gallus domesticus). Procedings of the 41st International Congress of the ISAE, Merida, 2007. pp 152 2. Christman, M.C., Miller, C.P. & Estevez, I. (2007). Mathematical Modeling and analysis of use of space. ADSA-PSA-AMPA-ASAS, 2007 Joint annual Meeting San Antonio, Texas July 8th-12th APoultry Sci. Vol., 86, Suppl. 1 pp. 417. (Invited presentation) 3. Mallapur, A., Estevez, I., Miller C. & Christman, M.C. (2007). Animal movement and space use in confined environments: Influence of group size and enclosure size. In Prep
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Progress 09/15/06 to 09/14/07
Outputs
In experiment 1 40 birds were divided into three group sizes (5, 10 and 20) and observed in testing arenas of three sizes (5, 10 and 20 m2). Results of the experiment indicate that birds in larger group sizes had longer net distances while birds in larger pen had longer net distances, total distances, mean and maximum step-lengths. We concluded that pen size have far more significant effects on how chickens use space as compared to the effects of group size. This paper will be submitted for publication soon. The remaining experiments on chickens (experiments 2, 3 and 4) have been completed. In experiment 2, we controlled for the effects of group size and density while in experiments 3 and 4 group size, density and pen size were maintained constant and the influence of enrichment panels (in experiment 3) and the positioning of food resources (in experiment 4) on movement was recorded.. Experiment 2 was completed in March 2007. For this experiment each group of birds were
temporarily divided into three group of 5, 10 and 20 birds and each of these groups were observed in testing arenas of 10 m2. Experiments 3 and 4, were conducted simultaneously from March to May 2007. In experiment 3 the movement of birds were recorded under three different treatments a) a control, b) four 1 m panels in a zigzag pattern and c) one 4 m panel in the center while in experiment 4 the positioning and size of food resources varied - a) one feeder in the center, b) two feeders, one at each end, and c) four feeders, one at each corner. For all experiments locations of each focal bird were collected continuously over a period of 5 min. Continuous locations were collected using a Tablet PC (Satellite R Series, Toshiba) as (X, Y) coordinates (in cm) and a modified version of the software The chickitaizer (Sanchez and Estevez, 1998). This modified version was developed by Sanchez and Estevez, (2006) and it allows the investigators to collect accurate location data directly into
the computer in XY coordinates while keeping track of all desired independent variable, the behavior of the birds and their identity. This modified software has improved our efficiency tremendously. In addition to completing all the animal experiments proposed in the grant, a simulation model of the movement and behavior of an animal in confined space was developed using a rule-based paradigm. First, model parameters were estimated using data collected in experiments 1 and 2. This work involved developing methods for uniquely distinguishing the different behavior observed in the birds. Some of the additional research areas are 1) estimation of model parameters and probability distributions using Monte Carlo Markov Chain estimation procedures, 2) development of statistical methods to test whether an animal modifies its movement patterns due to attraction to resources, 3) identifying measures of tortuosity that can distinguish differential responses of the animals' movement to
manipulative treatments such as group size or pen size, and 4) the development of tests of angular dispersion when the experimental design includes random effects.
Impacts
Through our research, we would like to provide a better understanding on how domesticated/ captive animals move and use space in confinement. This project will generate a large body of knowledge on how environmental and social factors affect the patterns of movement and use of space of broiler chickens. Most importantly, the development of a mathematical model of animal movement for confined animals, new methodology to calculate movement patterns, their complexity as measured by tortuosity (once developed and refined using our animal data), will be a powerful tool to evaluate commercial management practices relative to their effects on animal welfare (as measured by patterns of movements). We will be able to scientifically determine minimal space requirements and an optimal resource distribution to insure the health and welfare of domestic animals while maintaining high animal performance and productivity. In addition, the generated models of animal movement can be used
to explore the potential consequences of future environmental interventions before they are implemented. The outcomes of this research go beyond the proposed poultry experiments as the new statistical methodology developed can be applied to any studies that involve observation of animal movement in confinement (such as areas of toxicology and neurology).
Publications
- Mallapur, A., Estevez, I., Miller C. & Christman, M.C. (2007). Movement and use of the space in confinement; The effects of group size and pen size in broilers (Gallus gallus domesticus). Procedings of the 41st International Congress of the ISAE, Merida, 2007. pp 152
- Christman, M.C., Miller, C.P. & Estevez, I. (2007). Mathematical Modeling and analysis of use of space. ADSA-PSA-AMPA-ASAS, 2007 Joint annual Meeting San Antonio, Texas July 8th-12th APoultry Sci. Vol., 86, Suppl. 1 pp. 417. (Invited presentation)
- Mallapur, A., Estevez, I., Miller C. & Christman, M.C. (2007). Animal movement and space use in confined environments: Influence of group size and enclosure size. In Prep
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Progress 09/15/05 to 09/15/06
Outputs
We have developed the basic simulation model of the movement of an animal in confined space using a rule-based paradigm. Extensive computer programming and simulations have been run using Octave, a freeware version of Matlab to explore the effects of different parameterizations of the model on commonly used statistical measures. The model is based on a correlated random walk in which the movement is controlled by internal (memory) and external (resources and obstacles) forces. The two basic mechanisms of movement, step length and turning angle, are modified according to recent past movement of the animal, likelihood of specific behaviors such as stopping, nearness of the boundaries of the space, and nearness to resources. Model parameterization is based on six conditions: step length (the length of a single step in the walk), direction (the turning angle for the next step), stopping rule (a probability function for the animal taking a step length of 0), attraction to
edges of the enclousure (the probability of an animal moving toward a boundary or edge), space avoidance (probability of the animal moving away from previously encountered regions), and time avoidance (probability of space avoidance modified by the length of time since last encounter). We have begun development of statistical techniques for estimating descriptive measures of movement patterns such as angular dispersion, total distance moved, etc. Patterns of movement are compared for different environmental conditions. As part of the comparisons, we are considering the sensitivity of the statistics to determine the sensitivity of the measures to varying treatments. The first experiment on chickens has also been conducted. In this experiment we controlled for the effects of group size, density and pen size in a multifactor experimental design. This will allow us to tease apart the effects of these factors on patterns of movement. For this experiment which was completed in October 2006,
336 birds were divided into 8 groups of 42 (35 experimental birds plus 7 extra birds/pen to maintain a balance in case of a mortality). Each group of 42 birds was housed in a 5m2 pen. All birds were double-tagged for individual recognition. For testing, each group of birds were divided temporarily into three group sizes (5, 10 and 20) and each of these groups were observed in testing arenas of three sizes (5, 10 and 20 m2) to study the influence of group size, density, and pen size on movement. Locations of each focal bird were collected continuously over a period of 5 min. Continuous locations were collected using a Tablet PC (Satellite R Series, Toshiba) as (X, Y) coordinates (in cm) and a modified version of the software "The chickitaizerī" (Sanchez and Estevez, 1998). This modified version was developed by Sanchez and Estevez, (2006) and allows the investigators to collect accurate location data directly into the computer in XY coordinates while keeping track of all desired
independent variable, the behavior of the birds and their identity. This modified software has improved our efficiency tremendously.
Impacts
Through our research, we would like to provide a better understanding on how domesticated/ captive animals move and use space in confinement. This project will generate a large body of knowledge on how environmental and social factors affect the patterns of movement and use of space of broiler chickens. Most importantly, the development of a mathematical model of animal movement for confined animals, new methodology to calculate movement patterns, their complexity as measured by tortuosity (once developed and refined using our animal data), will be a powerful tool to evaluate commercial management practices relative to their effects on animal welfare (as measured by patterns of movements). We will be able to scientifically determine minimal space requirements and an optimal resource distribution to insure the health and welfare of domestic animals while maintaining high animal performance and productivity. In addition, the generated models of animal movement can be
used to explore the potential consequences of future environmental interventions before they are implemented. The outcomes of this research go beyond the proposed poultry experiments as the new statistical methodology developed can be applied to any studies that involve observation of animal movement in confinement (such as areas of toxicology and neurology).
Publications
- No publications reported this period
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