|Carroll, Jeffery - Jeff Carroll|
Submitted to: Prince Agri Products Feed Ingredient Conference
Publication Type: Proceedings
Publication Acceptance Date: 8/30/2005
Publication Date: 8/31/2005
Citation: Carroll, Jeffery A., Gaines, Aaron, Allee, Gary. 2005. Immunity in swine: An overview of nutritional modulation of the acute phase response. Prince Agri Products Feed Ingredient Conference Proceedings. CD-ROM. Interpretive Summary:
Technical Abstract: It has been well established that an animal’s ability to protect itself from diseases and other immunological challenges within its environment depends upon the presence of a well developed and properly functioning immune system. It is also common knowledge that animals which possess an adequate level of immunological protection exhibit greater reproductive capabilities, enhanced growth, and increased feed efficiency. While activation of various physiological processes in response to an immunological challenge is necessary for survival, there is an associated energy cost to the pig which reduces the overall productivity potential. Creating and maintaining a febrile response alone is very energy intensive. It has been estimated that there is approximately a 10 to 15% increase in energy usage for every degree of body temperature increase associated with an immune response. Utilizing energy resources to mount an adequate immunological response limits the energy that could otherwise be used for other economically important biological functions such as growth, reproduction, and lactation. However, the reality is that activation of the immune system is necessary to prevent disease within the animal, and without diverting nutrients to support immunological functions, there would be significant economic losses associated with death loss, decreased feed efficiency, and reduced average daily gain. This issue becomes especially important when addressing the weaned pig. To prevent the potential detrimental effects associated with weaning pigs with an immature immune system, swine producers have utilized low or sub-therapeutic levels of antibiotics (i.e., antibiotic growth promoters, AGPs) in the pig’s diet. However, in recent years, livestock producers have been under considerable pressure from consumer groups to eliminate the use of sub-therapeutic levels of antibiotics in livestock production. Therefore, extensive efforts are underway to identify non-antibiotic alternatives to AGP’s. The primary immunologically active compounds which have been investigated in the arena of animal agriculture include antibodies, cytokines, direct-fed microbials, and various nutritional supplements such as spray-dried plasma (SDP) and fish oil. Our research efforts have focused primarily on the use of SDP, fish oil, and more recently, yeast cell products as nutritional supplements to enhance the immune system of the young pig. Results from our studies have demonstrated that inclusion of non-antibiotic supplements such as SDP, fish oil, or yeast cell products in the weaned pig’s diet for the first 10 to 14 days postweaning results in significant alterations in indices of the stress and immune responses following an LPS challenge. Based on the indices measured in our studies, it would appear that these supplements offer immunological protection to the young pig, thus allowing more nutrients to be diverted towards growth during this critical period of development. Collectively, our data suggests that these supplements may be viable alternatives to sub-therapeutic levels of antibiotics in future livestock production.