Source: UNIV OF MINNESOTA submitted to NRP
IMPROVING PERFORMANCE AND WELFARE OF SWINE IN ALTERNATIVE HOUSING SYSTEMS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0212665
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Oct 1, 2010
Project End Date
Sep 30, 2015
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
UNIV OF MINNESOTA
(N/A)
ST PAUL,MN 55108
Performing Department
Animal Science
Non Technical Summary
Due to concerns about animal welfare by the general public, some types of confinement swine housing have been banned in some regions of the world, as well as in the United States. In the past few years, seven states (FL, AZ, CA, MI, MA, CO, OR) have banned individual stalls for pregnant sows. In addition, Smithfield and Maple Leaf Foods, two of the largest pork producers in North America, have announced a voluntary move away from the use of gestation stalls in favor of group housing systems. As a result, alternatives to confinement swine production systems have emerged rapidly worldwide. The alternatives, such as group-housing of gestating sows, and large pens for farrowing and lactating sows, may improve animal welfare by providing opportunities for pigs to perform natural behaviors. However, to maintain rich welfare and competitive performance of pigs in these alternative systems, management faces great challenges. For instance, group housing of gestating sows improves sow welfare by providing freedom of movement to the sow, but also induces aggression among the sows. Loose farrowing systems(where sows give birth to piglets in large pens) allows sows to perform natural behaviors, such as nest building, but also results in more piglets being laid on by the sows. To ensure well-being of swine in alternative housing systems, feasible management strategies are needed. This project focuses on developing the best management protocols to enhance animal well-being and performance in alternative housing systems. To reduce piglet mortality in loose farrowing systems, we will investigate major factors that affect piglet survival in a loose system. These factors will be categorized into factors related to sows, to piglets, and to housing environments. By evaluating interactions of these factors in the three categories on piglet survival, we hope to find the optimal conditions that would maximize piglet survival in loose farrowing systems. To ensure sows' well-being in different housing systems, the first step is to assess animal well-being by repeatable and objective methods. To explore such methods, we will investigate the repeatability and feasibility of each welfare indicator (fear response, performance, longevity, injuries, lameness, salivary and fecal cortisol)for on-farm animal well-being assessment. Based on the repeatability of each welfare indicator measured, we will develop an animal-based welfare assessment protocol which can be used for on-farm well-being assessment. To develop the best practices of rearing group-housed gestating sows, we will evaluate effects of group size, floor space, grouping strategy and feeding management on performance and well-being of group-housed gestating sows. We will investigate two types of group-housing systems which are used most in the swine industry: one with electronic sow feeders, and another with feeding on the floor. Performance and well-being of sows will be evaluated by reproduction performance, body condition, longevity, lameness, contisol concentrations, and behaviors. The results will reveal the optimal management strategies for group-housed gestating sows.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
31535101060100%
Knowledge Area
315 - Animal Welfare/Well-Being and Protection;

Subject Of Investigation
3510 - Swine, live animal;

Field Of Science
1060 - Biology (whole systems);
Goals / Objectives
To maintain rich welfare and competitive performance of swine in alternative systems, management faces great challenges. For instance, group housing of gestating sows improves sow welfare by providing freedom of movement to the sow, but also induces aggression among the sows. Loose farrowing allows sows to perform natural behaviors, but also results in more piglets being laid on by the sows. The overall goal of this project is to develop the best management protocols to enhance animal well-being and performance in alternative housing systems. The specific objectives are: 1. Reduce pre-weaning mortality of piglets in loose farrowing systems, 2. Assess well-being of gestating sows in different housing systems, and 3. Explore the best practices for rearing group-housed gestating sows. The results of the project will be presented to producers and researchers nationwide at the Joint Meeting of the American Society of Animal Science (ASAS), and Midwestern Section of ASAS, and to local producers at the Minnesota Pork Congress and by seminars and workshops through the extension programs of Minnesota Pork Board and University of Minnesota. Updates on the study will be available on the website and newsletters of the West Central Research and Outreach Center, and local newspaper and radio programs. Application of the results will be addressed in some national magazines, such as National Hog Farmer magazine, and The Land magazine. The final results will be published in the Journal of Animal Science to reach a worldwide audience.
Project Methods
To achieve objective 1, factors affecting piglet mortality in a bedded group-farrowing system will be systematically investigated. These factors will be categorized into factors related to sows, to piglets, and to housing environments. In the sow category, parity (age), body weight (size), personality and behavior (fear response and maternal care) will be the research focus. In the piglet category, litter weight at birth, variation in birth weight within a litter, birth weight of individual piglets, and individual birth weight relative to the mean weight of the litter will be the major factors to be investigated. In the housing environmental category, affecting factors will include room temperature, humidity, and the amount of bedding. The project will particularly evaluate interactions of these factors in the three categories on piglet survival using a systematic approach. To achieve the second objective, well-being of gestating sows will be assessed in 5 different housing systems. The five housing systems include four group-housing systems (pens with electronic sow feeders, pens with free-access stalls, pens with feeding stalls, and pens on floor feeding) and a confinement system (gestation stalls). Sow welfare will be assessed by fear response, performance, longevity, injuries, lameness, salivary and fecal cortisol across the housing systems. Fear response of sows in different parity will be assessed by behavioral tests (voluntary approach to human in open field, return to human in open field, return to human in home pen or in stalls). Based on the repeatability of each welfare indicator measured, we will develop an animal-based welfare assessment protocol which can be used for on-farm well-being assessment. the third objective will be achieved by studying effects of group size, floor space, grouping strategy and feeding management on performance and well-being of group-housed gestating sows. We will investigate two types of group-housing systems which are used most in the swine industry: one with electronic sow feeders, and another with feeding on the floor. Performance and well-being of sows will be evaluated by reproduction performance (wean-to-estrous interval, farrowing rate, total litter size, born alive litter size, still born piglets at birth), body condition, longevity, lameness, salivary contisol concentrations, and behaviors (aggressive, postural and stereotypic behaviors). The project addresses contemporary issues that both swine producers and consumers are concerned about. In the long term, the project will meet the increased demand for information on management in alternative swine production systems.

Progress 10/01/10 to 09/30/15

Outputs
Target Audience:The target audiences for this project were swine producers, swine scientists, extension educators, veterinarians, graduate and undergraduate students who are interested in alternative swine production. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project provided opportunities for the PI to present and discuss the results with scientists from the Europe, Canada, and other states of the U.S. at several national and regional meetings, which benefited the professional development of the PI. Furthermore, the project provided training opportunities for graduate students, undergraduate students and visiting scholars to conduct research at both the University of Minnesota and on commercial farms. In return, the trainees contributed to the project through data collection, data analysis and writing publications.The outcomes of this project contributed to our knowledge of swine behavior and welfare science.? How have the results been disseminated to communities of interest?The results of this project have disseminated to local swine producers through publications in the local newspaper, the WCROC newsletter, and the University of Minnesota Extension website, presentations at seminars, and personal communications. In addition, the results have been disseminated to swine scientists and extension educators world-wide through presentations at national and regional meetings of animal science, and publications in peer-reviewed journals. Through the project, we have identified feasible management strategies to enhance the well-being and performance of swine in alternative housing systems. Animal scientists, extension educators, and swine producers will use the knowledge and management strategies tested in the project to improve animal welfare in swine production through their teaching/extension programs and production practices. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Modern swine production is shaped by societal needs. Societal concerns about animal welfare have resulted in some confinement housing systems, such as gestation stalls, being banned in several states of the United States. As a result, alternatives to confinement housing systems have emerged rapidly. To ensure the well-being of swine in alternative housing systems, feasible management strategies are needed. This project focused on developing the best management protocols to enhance animal well-being and performance in alternative housing systems. Pre-weaning mortality of piglets remains both an economic and welfare issue on alternative swine farms. A large variation in piglet mortality exists among sows, with some sows (high risk sows) losing more piglets than others. Risk factors contributing to piglet pre-weaning mortality were assessed in a bedded, group-farrowing systems. High risk sows were found to have higher oxytocin concentrations compared to low risk sows. Based on the risk analysis, management strategies to reduce piglet mortality were developed and then validated on commercial farms. Furthermore, the well-being and performance of individual sows in group-gestation housing system was evaluated. The welfare of a sow in a group housing system depends on her age, experience, and social rank. The welfare of young and low ranking sows in group-housing systems has become a concern because they sustain more injuries and gain less weight during gestation than high ranking sows. Management strategies to protect young and low ranking sows were developed and tested. One strategy developed was to segregate young sows. Housing young sows separately from old sows improved the well-being and performance of young sows. Another strategy testedwas to provide hiding spaces for low ranking sows to avoid aggressive interactions with high ranking sows. Application of thestrategy improved the well-being of low ranking sows. These management strategies were further evaluated on a commercial farm. The interactive effect of group size and social rank on the well-being and performance of gestating sows in group pens with a floor feeding system was determined. The limited floor space allowance compromised the well-being young and low ranking sows. Housing in small pens improved the well-being of low ranking sows in group-housing system studied.

Publications

  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Cui, S. Q., J. E. Anderson, L. H. Wang, J. Deen, and Y. Z. Li. 2015. Automated monitoring of swine behavior using accelerometers: Classification of behavior of nursery pigs from acceleration patterns. J. Anim. Sci. 93 (E-Suppl.2): 102 (Abstr. 232).
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: He, Y., J. Deen, G. C. Shurson, and Y. Z. Li. 2015. Physiological characteristics of slow growing pigs from birth to market. J. Anim. Sci. 93 (E-Suppl.2): 103 (Abstr. 234).
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: He, Y., J. Deen, G. C. Shurson, and Y. Z. Li. 2015. Identifying risk factors of slow growth of pigs from birth to market. J. Anim. Sci. 92 (E-Suppl.2):103 (Abstr. 235).
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Cui, S. Q., X. B. Wang, X. K. Huang, Y. Xu, and Y. Z. Li. 2015. Association of IgG concentration in colostrum with diarrhea in piglets born to Min and Landrace sows. J. Anim. Sci. 93 (E-Suppl.2):106 (Abstr. 240).
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Seddon, Y. M., M. M. Bouvier, Y. Z. Li, and J. A. Brown. 2015. Mixing strategies for group-housed gestating sows: effects on productivity. J. Anim. Sci. 93 (Suppl. 2): 3 (Abstr. 006).
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Li, Y. Z., K. McDonalds, and H. W. Gonyou. 2015. Determining feeder space requirement for growing-finishing pigs. J. Anim. Sci. 93 (E-Suppl. 3):17 (Abstr. M30).
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Cui, S. Q., Y. Xu, X. K. Huang, X. B. Wang, and Y. Z. Li. 2015. A comparison for IgG absorption between Min and Landrace piglets. J. Anim. Sci. 93 (E-Suppl. 3): 635 (Abstr. W48).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Li, Y. Z. 2015. Research Update on Welfare and Management of Gestating Sows. Proceedings of China Swine Science Conference 2015. Xiamen International Conference and Exhibition Center, Xiamen City, Fujian Province, China. Sept. 19  21, 2015.
  • Type: Websites Status: Published Year Published: 2015 Citation: Li, Y. Z. 2015. Tail biting in pigs  what do we know about it? News from the WCROC, Sept. 2nd, 2015. http://wcroc.cfans.umn.edu/tail-biting. Accessed on Dec 28, 2015.
  • Type: Websites Status: Published Year Published: 2015 Citation: 5. He, Y. J., G. C. Shurson, J. Deen, and Y. Z. Li. 2015. Ample feeder space benefits slow growing pigs in nursery phase. University of Minnesota Extension. Available at: http://www.extension.umn.edu/agriculture/swine/feeder-space-benefits-slow-growing-pigs/index.html. Accessed on Dec. 22nd, 2015.


Progress 10/01/13 to 09/30/14

Outputs
Target Audience: The target audiences for this project are swine producers, swine scientists, extension educators, veterinarians, graduate and undergraduate students who are interested in alternative swine production. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? The project provided an opportunity for the PI to present and discuss the results with renowned scientists from the Europe, Canada, and other states of the U.S. at the 2014 Joint Meeting of American Society of Animal/Dairy Science, and the Canadian Society of Animal Science, which benefit the professional development of the PI. Furthermore, the project also provided opportunities for two visiting scholars and an undergraduate student to be trained for conducting research at both the University of Minnesota and the commercial farm. In return, the trainees contributed to the project through data collection and analysis. How have the results been disseminated to communities of interest? The results of this project have outreached local swine producers through publications in the local newspaper, the WCROC newsletter, and the University of Minnesota Extension website, presentations at seminars, and personal communications. In addition, the results have been disseminated to swine scientists and extension educators world-wide through presentations at national and regional meetings of animal/swine science and publications in peer-reviewed journals. The outcomes of this project contribute to our knowledge of sow well-being in group-housing systems. Swine producers, animal scientists, and extension educators would use the knowledge and management strategies tested in the project to improve well-being of sows in group-housing systems through their production practices and teaching/extension programs. What do you plan to do during the next reporting period to accomplish the goals? During the next reporting period, we will continue our research effort to improve well-being of group-housed sows. We will attempt to determine the optimal floor space allowance for group-housed sows. While the optimal floor space allowance will safeguard the well-being of group-housed sows, it will also allow us to utilize the floor space most efficiently. Currently, there is no scientifically-established recommendation for floor space allowance for group-housed sows. So, our effort will help the U.S. pork producers safeguard the well-being of sows in group-housing systems and simultaneously maintain profitability of swine production.

Impacts
What was accomplished under these goals? Research effort has been devoted to develop management strategies to improve sow well-being in group-housing systems. The welfare of a sow in a group housing system depends on her social rank, with low ranking sows usually sustaining more skin lesions than high ranking sows. A study was conducted to investigate what makes a sow high or low ranking, and how social rank affects the well-being and reproductive performance of sows. Sows (n = 150, parity 1 to 9) were mixed in pens of 15 sows with feeding stalls after weaning. Aggressive interactions were video-recorded during the first 6 h after mixing. Among the 15 sows in each pen, three groups of 5 were classified as high, middle, and low ranking, respectively, based on outcomes (won, lost, and unsolved) of aggressive interactions. Individual weight, body condition, backfat thickness, heart rate, and fear response of the sows were measured during gestation. Litter size and piglets' weights were recorded at farrowing and at weaning. Results indicate that high ranking sows were older, heavier, and less fearful than low ranking sows. High ranking sows farrowed more piglets, but also had higher pre-weaning mortality of piglets than low ranking sows. High and low ranking sows were not different in body condition, backfat thickness, heart rate, or body weight of piglets farrowed or weaned. These results suggest that young and lightweight sows will become low ranking sows in a group. Low ranking sows can suffer social stress, as indicated by their fear responses. To improve well-being of low ranking sows, producers may consider sorting sows by age or weight in group housing systems. Another study was conducted to investigate the interactive effect of group size and social rank on the well-being and performance of gestating sows in group pens with a floor feeding system. Pregnant sows (n = 152, parity 1 to 6) were allocated to 4 large pens (26 sows/pen) and 8 small pens (6 sows/pen) at 35 d after mating. Both large and small pens provided the same floor space allowance (1.5 m2/sow). Results indicate that there was no interaction of group size and social rank for any variable measured. Low ranking sows fought less frequently (9.3 vs. 20.7 fights/sow/2h) than high ranking sows, but had similar skin lesions at 24 h after mixing as high ranking sows. Low ranking sows sustained more skin lesions than high ranking sows at 5 weeks after mixing. Low ranking sows and high ranking sows entered gestation pens with similar body weights, but low ranking sows gained less weight (33 vs. 50 kg), and had lower weights (250 vs. 268 kg) before farrowing than high ranking sows. Group size did not affect the number of fights per sow involved, but sows in large pens had more skin lesions at 24 h and at 5 weeks after mixing than sows in small pens. Neither social rank of the sow nor group size affected litter size or litter weight at birth or at weaning. These results suggest that low ranking sows had poor well-being than high ranking sows in pens with the floor feeding system, as indicated by reduced weight gain and increased skin lesions. Small group size appears better than large group size for sow well-being because sows in small groups had fewer skin lesions than in large groups. The limited floor space allowance and the competitive floor feeding system could be major contributors for the compromised well-being of group-housed sows in this study. Segregating low ranking/younger sows from high ranking/older sows and housing them in small pens may improve well-being of low ranking sows in group-housing systems.

Publications

  • Type: Journal Articles Status: Published Year Published: 2014 Citation: 1. Phillips, C. E., C. Farmer, J. E. Anderson, L. J. Johnston, G. C. Shurson, J. Deen, D. H. Keisler, A. M. Conner, and Y. Z. Li. 2014. Preweaning mortality in group-housed lactating sows: Hormonal differences between high risk and low risk sows. J. Anim. Sci. 92: 2603-2611.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: 2. Li, X., S. K. Baidoo, Y. Z. Li, G. C. Shurson, and L. J. Johnston. 2014. Interactive effects of distillers dried grains with solubles and housing system on reproductive performance and longevity of sows over three reproductive cycles. J. Anim. Sci. 92:1562-1573.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: 1. Li, Y. Z., and L. H. Wang. 2014. Effects of group size and social rank on welfare and performance of gestating sows in a group-housing system with floor feeding. J. Anim. Sci. 92 (E-Suppl.2):406 (Abstr. 0812).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: 2. Wang, L. H., L. J. Johnston, and Y. Z. Li. 2014. Effects of social rank on agonistic behaviors and associated injuries of gestating sows at mixing. J. Anim. Sci. 92 (Suppl.2):115 (Abstr. 262).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: 3. Wang, L. H., L. J. Johnston, and Y. Z. Li. 2014. What determines the social rank of a sow in a group-housing system? J. Anim. Sci. 92 (Suppl.2):116 (Abstr. 263).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: 4. He, Y., J. Deen, G. C. Shurson, and Y. Z. Li. 2014. Identifying characteristics of slow-growing pigs from birth to 9 wk of age and growth performance responses to feeder space postweaning. J. Anim. Sci. 92 (Suppl.2):6 (Abstr. 013).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: 5. He, Y., J. Deen, G. C. Shurson, C. Chen, and Y. Z. Li. 2014. Identifying factors associated with slow growth of pigs from birth to market. Allen D. Leman Swine Conference: Recent Research Reports. Vol. 41: 31.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: 6. Bouvier, M. M., S. A. Ethier, Y. M. Seddon, Y. Z. Li, and J. A. Brown. 2014. Mixing strategies for group housed sows: effects on aggression and productivity (Abstr.). Intl. Soc. Appl. Ethol. (ISAE) North Am. Reg. Mtg., May 30-31, 2014, East Lansing, MI.
  • Type: Websites Status: Published Year Published: 2014 Citation: 1. Li, Y. Z. 2014. Sow welfare research update: Solving the problem of hunger and aggression in gestating sows. University of Minnesota Extension. http://www.extension.umn.edu/agriculture/swine/solving-the-problem-of-hunger-and-aggression-in-gestating-sows/index.html
  • Type: Websites Status: Published Year Published: 2014 Citation: 2. Martin, W., S. Schieck, and Y. Z. Li. 2014. Biosecurity for alternative pig farms. University of Minnesota Extension. http://www.extension.umn.edu/food/small-farms/livestock/swine/biosecurity-for-alternative-pig-farms/index.html
  • Type: Websites Status: Published Year Published: 2014 Citation: 3. Li, Y. Z. 2014. What determines the social rank of a sow in a group-housing system? University of Minnesota Extension. http://www.extension.umn.edu/agriculture/swine/what-determines-social-rank-of-sow/index.html
  • Type: Websites Status: Published Year Published: 2014 Citation: 4. Li, Y. Z. 2014. New project in 2015: Research on tail biting and tail docking in pigs. University of Minnesota Extension. http://www.extension.umn.edu/agriculture/swine/research-on-tail-biting-and-docking/index.html
  • Type: Other Status: Published Year Published: 2014 Citation: 5. Li, Y. Z. 2014. Using individual feeding stalls to protect low ranking sows in group housing systems. Morris Sun Tribune  Farm Addition. March 15, 2014.


Progress 01/01/13 to 09/30/13

Outputs
Target Audience: The target audiences for this project are small-scale swine producers, swine scientists, extension educators, and veterinarians who are interested in alternative swine production. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? The project created training opportunities for a graduate student, an undergraduate student, and a visiting scholar to research alternative swine production. The trainees contributed to the project through data collection, data analysis, and drafting manuscripts for publication. How have the results been disseminated to communities of interest? The results were presented to swine producers through seminars, individual consultation, and through publications in the WCROC newsletter, the local newspaper, and the University of Minnesota Extension website. In addition, the results were disseminated to swine scientists through publications in peer-reviewed journals and presentations at regional and international symposiums. The information helps pork producers identify and manage risk factors that threaten well-being and performance of pigs in alternative housing systems. Pork producers would apply the strategies we developed through the project to produce pork in a way that society desires. What do you plan to do during the next reporting period to accomplish the goals? During the next reporting period, we will continue our effort to understand and improve well-being of pigs in alternative housing systems. We will focus on investigating the well-being level of individual sows and identifying sows that are less competitive or more stressed in a group. Then, we will attempt to develop strategies to reduce the stress level and improve the well-being of less competitive sows in alternative housing systems.

Impacts
What was accomplished under these goals? Pre-weaning mortality remains both an economic and a welfare issue on alternative swine farms. A large variation in piglet mortality exists among sows, with some sows (high risk sows) losing more piglets than others. High risk sows may be more stressed than low risk sows, resulting in higher pre-weaning mortality of piglets. To characterize these high risk sows, we compared hormonal differences between high risk and low risk sows. Sixty three sows farrowed (gave birth to piglets) in a group-farrowing system were studied. Of these sows, 7 high risk sows and 7 low risk sows were identified and blood samples were collected from each sow 2 days pre-farrowing through 2 days post-farrowing through an indwelling ear vein catheter. Results indicate that there was no difference in cortisol concentration between high risk and low risk sows. Likewise, prolactin and urocortin concentrations did not differ between high risk and low risk sows. However, high risk sows had higher oxytocin concentrations compared to low risk sows. This study begins to identify endocrinological differences between sows that have a higher pre-weaning mortality to those that have a lower pre-weaning mortality in a group-farrowing system. The results help us understand the maternal biology that contributes to piglet survival. In another study, we investigated strategies to protect low ranking sows in a bedded, group-gestation system. The welfare of low ranking sows in group-housing systems has become a concern because they sustain more injuries caused by fighting and gain less weight during gestation than high ranking sows. A strategy to solve the problem is to provide hiding spaces for low ranking sows to avoid aggressive interactions with high ranking sows. To test the strategy, we evaluated whether open stalls can be used by low ranking sows as hiding spaces during mixing. Pregnant sows were allocated two pen-treatments: pens with open stalls, and pens without open stalls. All sows in each pen were video-recorded and aggression during the first 4 h after mixing was registered. A ranking index was determined for each sow based on outcomes of aggression. Results indicate that low ranking sows spent more time in stalls than high ranking sows after mixing. Sows in pens with open stalls fought less frequently and had fewer injuries than sows in pens without stalls. Neither pen treatment nor ranking affected changes in weight gain, body condition or back fat thickness during the gestation period. These results suggest that open stalls can be used as hiding spaces by low ranking sows to avoid fighting and reduce associated injuries during mixing. Pork producers can apply this strategy to protect low ranking sows and consequently improve well-being and performance of sows in group-housing systems.

Publications

  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Li, Y. Z., C. E. Phillips, L. H. Wang, X. L. Xie, S. K. Baidoo, G. C. Shurson, and L. J. Johnston. Effects of distillers dried grains with solubles on behavior of sows kept in a group-housed system with electronic sow feeders or individual stalls. Can. J. Anim. Sci. 93: 57-66.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Li, Y.Z., and H.W. Gonyou. Comparison of management options for sows kept in pens with electronic feeding stations. Can. J. Anim. Sci. 93:445-452.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Johnston, L.J., and Y.Z. Li. Performance and well-being of sows housed in pens retrofitted from gestation stalls. J. Anim. Sci. 91: 5937-5945.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Li, Y. Z., and H. W. Gonyou. Effects of management options on performance of gestating sows housed in an electronic sow feeder system. J. Anim. Sci. 91 (E-Suppl.2):19 (Abstr. O057).
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Johnston, L., Y. Z. Li, and A. Hilbrands. Performance and well-being of pregnant sows housed in pens retrofitted from stalls. J. Anim. Sci. 91 (E-Suppl.2):18 (Abstr. O054).
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Swanson, J., Y. He, L. J. Johnston, and Y. Z. Li. Can feeding stalls be used by low ranking sows as hiding spaces at mixing? J. Anim. Sci. 91 (E-Suppl.2): 89 (Abstr. P001).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Li, X., G. C. Shurson, S. K. Baidoo, Y. Z. Li, and L. J. Johnston. Effects of gestation housing system on sow performance and longevity over three reproductive cycles. Manipulating Pig Production. Proceedings of the 14th Biennial Conference of the Australasian Pig Science Association (APSA), Melbourne Australia, Nov. 2013.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Li, X., G. C. Shurson, S. K. Baidoo, Y. Z. Li, and L. J. Johnston. Interactive effects of distillers dried grains with solubles (DDGS) and housing system on litter performance, sow productivity, and sow longevity over 3 reproductive cycles. J. Anim. Sci. 91 (E-Suppl.2):89 (Abstr. P003).


Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: The results were presented to swine producers at workshops organized by the Land Stewardship Project and the Alternative Swine Housing Task Force, and disseminated through publications in The Land magazine and the WCROC newsletter. In addition, the results were disseminated to swine scientists through publications in peer-reviewed journals and presentations at the national and regional Annual Meetings of the American Society of Animal Science. PARTICIPANTS: Lee Johnston - West Central Research and Outreach Center, Jon Anderson - University of Minnesota - Morris, Marcia Endres - Department of Animal Science, Wayne Martin, University of Minnesota Extension, Christina Phillips - Graduate Student, Lihua Wang - Visiting Scholar, Philip Kramer - Niman Ranch Field Agent (Pork Division), Farmers: Jim VanderPol, Kerkhoven, MN; Keith Ellis, Austin, MN; Justin Leonhardt, Kellogg, MN; Martin Kramer, Algona, IA; Larry Gooden, Emmons, IA TARGET AUDIENCES: The target audiences for this project are swine scientists, extension educators, veterinaries, and pork producers who are interested in alternative swine production. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
To identify risk factors contributing to pre-weaning mortality of piglets and develop management strategies to reduce piglet mortality on small-sized commercial farms, we surveyed 45 family farmers who use loose farrowing systems in Minnesota and Iowa. Based on the survey and our research data, we developed a management protocol to reduce piglet mortality in alternative housing systems. The management protocol was provided to 6 farmers that were selected for the project. Sow performance and piglet mortality were monitored for 12 months after implementation of the protocol on these farms. The project contributes to knowledge of biological causes of piglet mortality in alternative housing systems. Results indicate that older sows had greater piglet morality and weaned fewer pigs than younger sows. Piglets that died before weaning were lighter at birth compared to piglets that survived to weaning. The project provided an opportunity to train a graduate student to conduct on-farm research and contributed to a Ph.D. thesis. Through the project, alternative pork producers learned how to identify and manage risk factors contributing to piglet mortality in loose farrowing systems. Pork producers would apply the strategies we developed through this project to improve piglet survival and produce pork in a way that society desires.

Publications

  • Li, Y. Z., J. E. Anderson, and L. J. Johnston. 2012. Animal-related factors associated with piglet mortality in a bedded, group-farrowing system. Can. J. Anim. Sci. 92:11-20.
  • Li, Y. Z., L. H. Wang, and L. J. Johnston. 2012. Effects of farrowing system on behavior and growth performance of growing-finishing pigs. J. Anim. Sci. 90:1008-1014.
  • Li, Y. Z., L. H. Wang, and L. J. Johnston. 2012. Sorting by parity to reduce aggression towards young sows in group-gestation housing systems. J. Anim. Sci. Published ahead of print. Aug. 2, 2012. doi:10.2527/jas.2011-4869.
  • Wang, L. H., Y. Z. Li, and L. J. Johnston. 2012. Effects of reduced nocturnal temperature on performance and behavior of nursery pigs. J. Integ. Ag. 11:1509-1516.
  • Li, Y. Z., L. J. Johnston, S. K. Baidoo, C. E. Phillips, L. H. Wang, X. L. Xie, and G. C. Shurson. 2012. Effect of feeding DDGS diets on behaviors of gestating sows in different housing systems. Abstracts of ADSA/ASAS Joint Meeting 2012. p. 507 (Abstr W16) Available at: http://www.jtmtg.org/2012/abstracts/502.pdf
  • Li, Y. Z., L. H. Wang, L. J. Johnston, A. M. Hilbrands, and X. L. Xie. 2012. Sorting by parity improves welfare and performance of young sows in a group-housing gestation system. Abstracts of Midwest ADSA/ASAS Meeting 2012, p. 19 (Abstr 48). Available at: http://adsa.asas.org/midwest/2012/MW2012Abstracts.pdf
  • Li, Y. Z., L. H. Wang, L. J. Johnston, A. M. Hilbrands, and X. L. Xie. 2012. Behavioral response of nursery pigs to reduced nocturnal temperature. Abstracts of Midwest ADSA/ASAS Meeting 2012, p. 20. (Abstr 52). Available at: http://adsa.asas.org/midwest/2012/MW2012Abstracts.pdf


Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: Results were disseminated through presentations and publications. During this reporting period, we presented the results at the Midwestern American Society of Animal Science (ASAS) Annual Meeting, National ASAS Annual Meeting, 72nd Minnesota Nutrition Conference, and two training workshops for pork producers. Three extension articles were published on the University of Minnesota Extension website and in local newspapers. Four abstracts and four research papers were published in academic journals. PARTICIPANTS: Lee Johnston, Marcia Endres, Jon E. Anderson, C. E. Phillips TARGET AUDIENCES: Swine scientists, pork producers, veterinarians, and extension educators PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Management strategies to improve performance and welfare of young sows in group-housed gestation systems were evaluated. Management strategies included separating young sows from old sows. Fighting at mixing, skin lesions caused by fights, and reproductive performance of sows were compared between treatment (sorted by age) and control (unsorted) groups. Outcome of this project included knowledge of social structure and its effects on welfare and performance in swine. Young sows sustained more skin injuries caused by fighting at mixing than older sows. By being separated from older sows, young sows can be shielded from severe injuries caused by initial aggression, gained more weight during the gestation period, and had higher farrowing rates compared with their counterparts housed with older sows. These results suggest that separating young sows from older sows can improve well-being and performance of these young sows in group-housed gestation systems. This project provides knowledge of social behavior in swine to scientists and extension educators so that they would apply the knowledge in their research and teaching. Pork producers would learn strategies to reduce fighting, and consequently, improve well-being and performance of group-housed gestating sows on their farms.

Publications

  • Li, Y. Z., L. H. Wang, and L. J. Johnston. 2011. Effects of farrowing system on behavior and growth performance of growing-finishing pigs. J. Anim. Sci. doi:10.2527/jas.2011-4390.
  • Phillips, C. E., Y. Z. Li, L. J. Johnston, A. E. Goplen, and G. C. Shurson. 2011. Technical note: A technique for ear vein catheterization in group-housed sows. J. Anim. Sci. doi:10.2527 /jas.2011-4390.
  • Li, Y. Z., and L. H. Wang. 2011. Effects of previous housing system on agonistic behaviors of growing pigs. Appl. Anim. Behav. Sci. 132: 20-26. Li, Y. Z., S. K. Baidoo, L. J. Johnston, and J. E. Anderson. 2011. Effects of tryptophan supplementation on aggression among group-housed gestating sows. J. Anim. Sci. 89: 1899-1907.
  • Li, Y. Z., J. E. Anderson, and L. J Johnston. 2011. Animal-related factors affecting piglet mortality in loose farrowing systems. J. Anim. Sci. 89 (E-Suppl. 2): 50 (Abstr. 9).
  • Phillips, C. E., Y. Z. Li, J. E. Anderson, L. J. Johnston, G. C. Shurson, and J. Deen. 2011. Assessment of sow fear, parity and season on piglet mortality in loose farrowing systems. J. Anim. Sci. 89 (E-Suppl. 2): 49 (Abstr. 8).
  • Phillips, C. E., Y. Z. Li, L. J. Johnston, G. C. Shurson, J. Deen, and C. Farmer. 2011. Association of sow fear with prolactin and cortisol concentrations pre- and post-farrowing. J. Anim. Sci. 89 (E-Suppl. 1): 12 (Abstr. M27).
  • Wang, L. H., and Y. Z. Li. 2011. Effects of farrowing systems on agonistic behaviors of growing pigs at mixing. Page 65 in Proc. 72nd MN Nutr. Conf., Owatonna, MN.
  • Li, Y. Z. 2011. Sorting sows by parity to reduce aggression in group-housing systems. Available at http://www.extension.umn.edu/swine/components/pubs/sorting-sows-by-pa rity.htm.
  • Li, Y. Z. 2011. How much space does a sow need in a group-housing system Available at http://www.extension.umn.edu/swine/components/pubs/how-much-space.htm .
  • Johnston, L. J., and Y. Z. Li. 2011. Reducing nocturnal temperature for nursery pigs. Morris Sun Tribune (A Special Supplement), Mar. 12, 2011. 4D. Morris, MN.


Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: The objective of the project is to develop and validate management strategies to improve performance and welfare of swine in loose housing systems. Results have been extensively disseminated through presentations and publications. During this reporting period, we attended the Midwestern Animal Science Annual Meeting and presented two posters of reducing piglet mortality in loose farrowing systems, and controlling aggression among group-housed sows. I was invited to give a seminar (entitled: Building efficient alternative systems) at the 2010 Iowa Pork Congress in Des Moines, IA. I also gave a seminar through internet (webinar) on reducing piglet mortality in loose farrowing systems, and a presentation on controlling aggression among group-housed gestating sows at the 71st Minnesota Nutrition Conference. I was interviewed for a news report (entitled: Researcher Yuzhi Li working to uncover secrets behind sows' aggressive behavior) by the Agri News. Two articles were published in "The Land" magazine and one article was published in the Morris Sun Tribune. In addition, two abstracts and one research paper were published in academic journals. PARTICIPANTS: Lee Johnston, Marcia Endres, Sam Baidoo, Jon E. Anderson, A. Hilbrands, C.E Phillips (graduate student). TARGET AUDIENCES: Pork producers and researchers in swine science. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Modern swine production is shaped by societal needs. Societal concerns about animal welfare have resulted in some confinement housing systems, such as gestation stalls, being banned in several states of the United States. Consequently, alternatives to confinement housing systems have emerged rapidly during the last decade. Alternative swine housing systems provide environments for animals to perform natural behaviors. But there are many challenges to enhancing animal welfare and simultaneously maintaining performance of swine in alternative systems. For instance, in group-gestation housing systems, a major challenge to management is to control aggression among sows which is detrimental to both welfare and performance of sows. In loose farrowing systems (sows give birth in large pens) where sows can perform some natural behaviors such as nest-building behavior, piglet mortality is two-fold greater than in conventional systems. Piglet mortality does not only cause concerns about piglet welfare, but also diminishes profitability of alternative swine production. To develop efficient management strategies to reduce piglet mortality, we investigated factors affecting piglet mortality in a group-farrowing system. The affecting factors were classified as sow-related factors and piglet-related factors. Multiparous sows (n = 108) from 8 breeding groups farrowed in a group-farrowing system were used. Total born, born alive, and still born piglets were recorded. Piglets were weighed individually within 24 h after farrowing, at the time farrowing pens were removed (d 10), and at weaning (d 28). Behavior of 39 focal sows during farrowing was video-recorded, from which farrowing duration, inter-birth interval, and frequency of postural changes were determined. A total of 1,233 piglets were farrowed. Among these piglets, 94.3% were born alive, and 5.7% were still born. Of live born piglets, 20% died before weaning, with 50% of the total deaths occurring during the first 3 days after farrowing. Sows of parity 5 or greater had greater pre-weaning morality of piglets (28% vs. 14%, SE = 2.78; P < 0.01) and weaned smaller litters (8.6 vs. 9.8 piglets, SE = 0.30; P < 0.05) than sows of parity 2. Sows that farrowed piglets with greater variation (CV > 20%) for birth weight within-litter had greater pre-weaning mortality than sows that farrowed piglets with less variation (CV < 15%) for birth weight. Piglets that died during lactation were 0.62 lb lighter in birth weight (3.07 vs. 3.69 lb, SE = 0.14; P < 0.001) compared to piglets that were weaned. Farrowing behaviors of sows were not related to piglet mortality. Gender of piglets and cross-fostering did not affect piglet mortality. The results indicate that parity of sows and birth weight of piglets were the major animal-related factors that contributed to piglet mortality in the loose farrowing system studied. Piglet mortality can be reduced by increasing the proportion of young sows in the herd, and selecting sows against minimal birth weight in the loose farrowing system.

Publications

  • Li, Y. Z., L. J. Johnston, and A. M. Hilbrands. 2010. Pre-weaning mortality of piglets in a bedded, group-farrowing system. A Case Report. J. Swine Health Prod. 18 (2):75-80. Li, Y. Z., J. E. Anderson, and L. J. Johnston. 2010. Effect of parity on pre-weaning mortality and growth performance of piglets in a bedded, group-farrowing system. J. Anim. Sci. 88 (E-Suppl. 3):45 (Abstr.5). Li, Y. Z., C. E. Phillips, S. K. Baidoo, and L. J. Johnston. 2010. Controlling aggression among gestating sows. J. Anim. Sci. 88 (E-Suppl. 3):49 (Abstr.17). Li, Y. Z., C. E. Phillips, S. K. Baidoo, and L. J. Johnston. 2010. Effects of tryptophan supplementation on aggression among group-housed gestating sows. Page 43 in Proc. 71st Minnesota Nutr. Conf., Owatonna, MN (Abstr.). Li, Y. Z. 2010. Controlling aggression among group-housed gestating sows. The Land. March 19, 2010: A30 - The Pork Professor.
  • Li, Y. Z. 2010. Reducing piglet mortality in loose farrowing systems. The Land. Jun. 11th, 2010.
  • Li, Y. Z., J. E. Anderson, L. J. Johnston, and A. M. Hilbrands. 2010. Effect of parity on pre-weaning mortality and growth performance of piglets in a bedded, group-farrowing system. Morris Sun Tribune (A Special Supplement), Mar. 14, 2010. D9. Morris, MN.


Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: The objective of the project is to develop and validate management strategies to improve performance and welfare of swine in loose housing systems. Results have been extensively disseminated through presentations and publications. During this reporting period, I attended the Midwestern Animal Science Meeting and presented a poster regarding maternal fear on piglet mortality in loose farrowing systems. I also attended the Leman Conference and presented a poster on controlling aggression among group-housed gestating sows. At the Niman Ranch National Annual Meeting 2009, I gave a seminar on reducing piglet mortality in loose farrowing systems to alternative producers. Three articles were printed in the West Central News University of Minnesota, and one article was published in the Morris Sun Tribune. PARTICIPANTS: Lee Johnston, Marcia Endres, Sam Baidoo. C.E Phillips (graduate student), A.M. Besch (undergrad), E. Park (undergrad) TARGET AUDIENCES: Pork producers and researchers in swine science. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
To maintain rich welfare and competitive performance of swine in alternative systems, management faces great challenges. Group housing of gestating sows improves sow welfare by providing freedom of movement to the sow, but also induces aggression among the sows. Loose farrowing allows sows to perform natural behaviors, but also results in more piglets being laid on by the sows. We investigated whether supplementation of tryptophan, a precursor of serotonin, can control aggression among group-housed gestating sows. Results indicate that aggression among sows was intense during the first 6 hours, and decreased (P < 0.01) dramatically between 6 to 72 hours after mixing. The initial aggression caused scratches (P < 0.05) and elevated stress hormone cortisol concentrations (P < 0.01) in sows. Mature sows fought for longer periods (P < 0.05), but had fewer scratches (P < 0.05) than parity 1 sows. Supplementation of dietary tryptophan at twice the recommended inclusion rate for three days before and after mixing did not effectively reduce aggression and the associated stress in the sows. The greater aggression-induced injury in parity 1 sows implicates welfare concerns for these young sows in group-housing systems. These results suggest that young sows should be separated from mature sows to improve welfare of younger sows in group housing systems. In another study, we evaluated effects of sow parity and season on piglet mortality. Results indicate that young sows had larger live born litter size than old sows (P < 0.05). When litter size was equalized, parity 1 sows tended to wean more (P = 0.06), but lighter piglets (P < 0.01) with lower piglet mortality (P = 0.06) compared with mature sows. No differences were observed in farrowing duration, inter-pig birth intervals, postural changes during farrowing, and average daily gain of piglets among sow categories. During summer months, piglet mortality was greater than during other seasons (P < 0.01). These results suggest that piglet mortality in group-farrowing systems can be reduced by increasing the proportion of younger sows, and alleviating heat stress.

Publications

  • Strawford, M.L., Y.Z. Li, and H.W. Gonyou. 2008. The effect of management strategies and parity on the behavior and physiology of gestating sows housed in an electronic sow feeding system. Can. J. Anim. Sci. 88: 559-567.
  • Li, Y.Z. 2009. Effect of maternal fear on pre-weaning mortality of piglets in a loose farrowing system. J. Anim. Sci. 87: (Suppl. 3): 42.
  • Li, Y. Z., C.E. Phillips, S.K. Baidoo, and L. J. Johnston. 2009. Controlling aggression among gestating sows. Allen D. Leman Swine Conference, University of Minnesota. 36: 197.
  • Li, Y.Z. 2009. Is Maternal Fear Associated with Piglet Survival in Loose Farrowing Systems Morris Sun Tribune, March 11, 2009: Farm Prog. (A Special Suppl.). Morris, MN. Li, Y.Z. 2009. Transition of gestation stalls to group-housing - How much space does a sow need in a group-housing system West Central News. University of Minnesota. Mar 4, 2009.
  • Li, Y. Z. 2009. Controlling Aggression Among Group-housed Gestating Sows. West Central News. University of Minnesota. June 24, 2009.
  • Li, Y.Z. 2009. Pre-weaning Mortality of Piglets - How Can We Solve the Problem West Central News. University of Minnesota. Oct. 14, 2009.


Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: We disseminated information through WCROC newsletter, local radio program, workshops, seminars, and conferences. Presentations were made at the Animal Science meetings. PARTICIPANTS: Yuzhi Li was the principal investigator, and Lee Johnston, Marcia Endres, and Sam Baidoo were the co-investigators. Two staff members (Adrienne Hilbrands and Mark Smith) were involved in data collection and animal care. Two undergraduate students and one graduate student were trained in data collection and analysis of salivary cortisol. TARGET AUDIENCES: The audiences for the project are pork producers and researchers in swine science. PROJECT MODIFICATIONS: Due to the availability of sows, the second study was conducted on a commercial farm instead of SROC as original planned. The objectives and experimental design remained the same as in the original proposal, except the total number of animals on test was reduced from 240 to 200 sows, and the number of focal animals was reduced to from 24 to 12 due to smaller pen size. The number of replications within each of treatment and control group stayed the same as in the original plan. The modification did not compromise us to achieve the proposed objectives.

Impacts
Two studies were conducted. One study was to test the hypothesis that fear of people in sows can affect maternal behavior and consequently affect pre-weaning mortality of piglets. A total of 91 multiparous sows from 4 breeding groups were tested in a human approach and a novel object approach test during wk 13 of gestation. Based on fear response, sows were classified into three categories: fearful sows that spent more than 140 seconds (s) to approach a circle within 0.5 meters (m) of a person, least fearful sows that spent less than 50 s to approach the circle, and neutral sows in the intermedium (> 50 s but < 140 s). All sows farrowed in a group farrowing system where 8 sows shared a communal area, and farrowed in individual open pens. At farrowing, litter size was recorded. There were no significant differences in the number of born alive, stillborn, birth weight of piglets, CV of birth weight within a litter, and pre-weaning growth rate of piglets among maternal fear categories. Least fearful sows weaned more piglets than fearful sows (9.9 vs. 8.3 +/- 0.86, P < 0.05). These results support the hypothesis that fear of people in sows affected number of piglets weaned. Since least fearful sows weaned larger litters, selecting least fearful sows may increase the number of piglets weaned, especially in loose farrowing systems. Piglets were weaned at 4 wk of age. The second study was to investigate effect of short-term supplementation of dietary tryptophan on controlling aggression, the associated stress and reproductive performance in group-housed gestating sows. This study was to test the hypothesis that tryptophan, as a precursor of serotonin, may depress aggression among sows at grouping. The study was conducted on a commercial farm where all gestating sows were group-housed with electronic sow feeders. Four pens of 25 sows were allocated to each of control and treatment group. All sows were mixed at weaning. For sows in the treatment group, tryptophan (0.30% in diet) was supplemented in the diet for three days prior to, and after mixing. Sows in the control group were fed control diet (0.15% tryptophan in diet) throughout the whole period of gestation. Within each pen, 6 focal sows were designated, including 2 sows from each of parity 1, 2, and 3 or greater. Aggression involving focal sows was recorded by videotaping for 72 hr immediately after grouping. Salivary samples were collected on focal sows prior to, and at 48 hr after mixing for measurement of cortisol concentration. Injuries resulting from aggression were assessed on all sows on the same days that salivary samples were collected. Feeder entry and feed intake of all sows was determined from sow feeding records from mixing day (d 0) through d 7. Data of production performance (total litter size, live litter size, mummies and still born) were collected on all sows at farrowing. The study is in the process of data analysis.

Publications

  • Li, Y.Z. 2008. What is the real picture of piglet pre-weaning mortality in loose farrowing systems West Central News. University of Minnesota. July 9.
  • Li, Y.Z. 2008. Is Maternal Fear Associated with Piglet Survival in Loose Farrowing Systems West Central News. University of Minnesota. September 17.