Location: Livestock Behavior Research2011 Annual Report
1a. Objectives (from AD-416)
The long-term objective of this project is to optimize animal well-being and productivity. The approach is to focus on animal behavior, the outward expression of the cumulative effects of internal biological changes, to assess where challenges may exist and to develop alternative management strategies to solve these challenges. Over the next five years we will focus on the following objectives: Objective 1: Develop scientific measures of, identify husbandry and environmental challenges to, and develop sustainable alternatives that safeguard well-being of swine. Objective 2: Develop scientific measures of, identify husbandry and environmental challenges to, and develop sustainable alternatives that safeguard well-being of dairy cattle. Objective 3: Develop scientific measures of, identify husbandry and environmental challenges to, and develop sustainable alternatives that safeguard well-being of poultry.
1b. Approach (from AD-416)
This project will examine animal agricultural practices, using behavior, physiology, immunology, and neurobiology, in order to maximize both animal well-being and productivity. Our approach will be to conduct multiple research projects on common production practices and evaluate how these practices affect livestock behavior, physiology, and physical condition, and we will work to assess the animals’ mental state. This unit is charged with the difficult task of conducting research for three animal species: dairy cattle, swine, and poultry. To accomplish this goal, unit scientists representing different backgrounds and areas of expertise will work together on multiple and varying projects to cover the main issues characteristic of the production system of each species. The broad view of our ultimate goal is that we wish to 1) discover and further refine objective measures of stress, and 2) evaluate and create appropriate management and housing methods. Each objective in this project is a step forward toward our ultimate goal. Our success will provide stakeholders with assurance that animal well-being is optimized and it will provide producers with technology to remain competitive.
3. Progress Report
All research in this project is progressing well. Sow Lameness Research. We have 4 replicates of swine on dietary treatments aimed to increase cartilage health, and thus far, we have collected all the data on the first 2 reps of animals with the other animals on target for completion. This is a 3 year study so results are not yet expected. Our work to decrease stomach ulcers in sows is also progressing as planned. We have conducted the laboratory studies and are moving to implement treatments on the farm. Sow Ulcer Research. We have completed a study examining different dietary ingredients on behavior and gastric ulceration in gestating sows. We found little effect of our treatments, although gastric health tended to be best in sows fed a higher fiber diet. Further analysis is ongoing. Heat Stress in Poultry and Cattle. We have completed two experiments on heat stress in poultry. Data analysis is partially complete. We have identified genetic variations in stress responses in the lines selected based on egg production and longevity; and that oxidative damage can be reduced by antioxidants in the feed. One manuscript has been submitted and two more are in preparation. We have also collected data for the heat stress study of dairy calves with both control and heat stress data collection complete. Behavior data is analyzed. The experiment is currently being replicated at the Purdue Dairy Teaching and Research Center. One manuscript is prepared to be submitted. Sow Aggression. We have completed data collection on sow aggression from sows in pairs or groups. Data analysis is partially complete. We have identified differences that appear to be mostly driven by the number of sows that are mixed together and by the amount of space available at mixing. Data analysis is continuing. Poultry Aggression. We have completed one experiment on aggression in poultry. We have collected all the samples and data analysis is partially completed. We have identified that aggression in chickens can be reduced or inhibited by modifying the serotonergic system during brain development in the early embryonic stage. One manuscript has been submitted. Osteoporosis in White Leghorns. We have examined the effects of exercise, using perches, on bone mineralization in laying hens. All samples from the growing phase have been collected and data are being analyzed. Development of a novel housing system to allow continuous behavioral and physiological monitoring. We have carried out two studies to compare pigs housed in isolation versus complex environments in which pigs' preferences for different objects including a mirror, a mat and the opportunity to see another pig. We identified that the companion pig was preferred over the other enrichments when no-one was in the room. However, when a human entered, the preferences changed and the mirror became as preferred as the companion, emphasizing the importance of context when assessing preferences experimentally. The second study examined the effects of environmental enrichment objects on behavior and physiology of isolated pigs in a laboratory setting. Data collection is complete and analysis is ongoing.
1. Sows which were not housed beside one another make better group mates. The largest single challenge of keeping sows in groups is aggression. Sows will fight when mixed but there is little information on the effects of pre-exposure prior to mixing. ARS researchers at West Lafayette, Indiana, studied a method of introducing sows to decrease aggression. This method relies on ‘pre-exposure’ in which sows are housed side by side but protected from fighting with each other by housing in stalls. The study found that pre-exposure prior to mixing sows together in a group caused the sows to fight more, not less, when group housed. It appears that the inability of the sows to resolve aggressive interactions within the stalls actually promotes aggressive behavior when the sows are placed in groups, thus future work should use a different approach in which sows are able to resolve aggression with enough space to move away and prevent injury.
2. Oxytocin helps pigs to cope with stress. Weaning and mixing of pigs is a stressful event with which pigs need to learn to cope. The hormone oxytocin has been shown to be released in animals when they enter into positive social relationships. ARS scientists at West Lafayette, Indiana, found that intra-nasal administration of oxytocin helps pigs to cope with isolation stress. Thus inter-nasal oxytocin administration may prove useful in preparing pigs for stressful events, thus increasing their welfare and enhancing their productivity. Currently this technology is still being developed.Lay Jr, D.C., Kattesh, H.G., Cunnick, J.E., Daniels, M.J., Kranendonk, G., Mcmunn, K.A., Toscano, M.J., Roberts, M.P. 2011. Effect of prenatal stress on pig’s subsequent response to mixing stress and a lipopolysaccharide challenge. Journal of Animal Science. 89(6):1787-1794.