Transport losses in market weight pigs present financial, legislative, and well-being challenges to the U.S. swine industry. By first understanding the pig, and the unfamiliarity of the marketing process research may begin to identify potential stressors that impinge upon a pig throughout this process, and attempt to lessen or eliminate these stressors. Although some work has been reported which evaluated on-farm factors affecting transport losses in market weight pigs; considerable gaps in the scientific literature remain. Those gaps include pre-sorting prior to loading affects and grow-to-finish pen size environmental affects. Johnson et al. (2010) reported a 66 % reduction in transport losses in pigs raised in large pen configurations that were pre-sorted, however, the researchers could not determine if the transport losses reduction resulted from pre-sorting, pen size, or a combination of both factors. The objective of the first trial in the present study was to determine the effect of pre-sorting on stress responses and transport losses in market weight pigs. Although pre- sorted pigs had a lower acute stress response at the time of loading, there was no difference between pre-sorted and not pre-sorted pigs at the harvest facility. The objective of the second trial in the present study was to determine the grow-to-finish pen size effects on the stress responses and transport losses in the market weight pig. At loading, pigs from small pens had a lower incidence of open mouth breathing and skin discoloration, however; at unloading pigs from small pen had a greater skin discoloration incidence than their large pen counterparts. There were no differences observed in the present study for any transport loss measures between pigs originating from large and small pen sizes.
Overall transport losses from both treatment groups in both trials were approximately one half of the estimated national average reported from a summary of 23 commercial field trials (0.69 %; Ritter et al., 2009). The relatively very low overall transport losses
experienced amongst all treatments in the present study makes it is questionable whether using intervention strategies such as pre-sorting prior to loading and large pen size is
beneficial on production sites that are already experiencing low transport losses compared to the national average.
ACKNOWLEDGEMENTS
I have been blessed to have a wonderful network of people to guide and support me throughout my master’s work. I first would like to thank my major professor, Dr. Anna Johnson for her guidance, support, patience, and advice throughout the past two years. I truly feel so lucky to have had you as a mentor, you have given me many great opportunities throughout my master’s work, and I have learned so much from you. I also greatly
appreciate your encouragement of me to pursue further education past my master’s degree. I think you provided me with the small bit of confidence that I needed to allow me to believe in myself and believe that I have what it takes.
I would also like to thank Dr. Kenneth Stalder. I am so thankful for your help with my endless statistics questions, and I appreciate your patience when sometimes I may not have caught on right away! Also I thank Dr. Joshua Selsby for your time in editing my various manuscripts. It was very valuable to me to have you on my committee; your different background allowed you to offer different opinions and perspectives on things I would have otherwise overlooked.
A big thank you goes to Dr. Matthew Ritter. To be able to work with someone like you, with your vast background and knowledge in my research area was a wonderful and valuable resource to me. I appreciate your willingness to answer my numerous questions and offer your insight. I truly learned so much from you!
Thank you to everyone who helped with data collection, especially Larry Sadler. I know that collecting data in the middle of the night is less than ideal, but I appreciate more
than you can know your willingness to volunteer of your time to help me. I also thank Allison Meiszberg, Rachel Witte, and Jennifer Groen for their help with data collection.
I thank Iowa Select Farms for allowing me the use of their pigs and facilities for both research studies. I thank especially Dr. Howard Hill, Mike Faga, Alan Whiley, Corky Feurbach, Steve Abrams, Ryan Rienke, and Bill Allen for your kindness and willingness to help out. Working with great people like yourselves made my job a lot easier.
I also would like to thank JBS Swift and Co. for allowing my team and I to come into the harvest facility. I appreciate the extra effort all the employees put in to make sure that we were able to collect our data. A special thanks to Ryan Bailey for helping me in organizing data collection at the plant.
I would like to thank all my close friends for their friendship and support, especially Amy Schreiber and Mallory Kauffman. Their willingness to listen and provide support throughout these past two years has helped carry me through a few stressful days and if I was especially having a bad day- I could always rely on you both to provide me with a little humor to cheer me up!
I owe a huge thanks to my parents, Merlin and Becky, for giving me the upbringing that every child should be lucky enough to have. From a very young age, I helped out in about every aspect of farm life, and on the farm is where I learned to both love and respect animals through watching you both. There is no question I would not be on the path I am today if I hadn’t been so involved in the family farm operation. Perhaps more importantly
though, you taught me good values about life in general and these values will remain with me the rest of my life.