Immunology and microbial ecology of the gastrointestinal tract of suckling and nursery phase pigs
Abstract
The swine industry is faced with many challenges, including the well-being of the animal and consumer. From birth, piglets are exposed to a myriad of stressors (i.e. processing, weaning, and transportation) which may compromise their innate immunity, as well as, allow for a greater number of opportunistic pathogens to colonize their gastrointestinal tract. Increased protection of piglets generally arises from the use of antibiotics. However, increasing bacterial species developing resistance to several antibiotics has become a great concern to not only the producer but also the consumer. Therefore, the overall goal of this research was to study alternative means of protecting the immunity and microbial ecology of the piglet for needed benefit to the health of the animal. The specific objectives were to measure the effects of (1) a commercial yeast product, containing Saccharomyces cerivisiae , on the piglet when exposed to weaning and transport stressors; and (2) a yeast cell wall component, beta-glucan, plus ascorbic acid versus two types of antibiotics, tylosin and carbadox, on the immune system, microbial ecology, and growth and development of weanling and nursery phase piglets. The central hypothesis of this research was that the use of antibiotics is expected to have a direct impact on the intestinal microbial ecology, and consequently on immune responses from the host, whereas yeast supplementation is expected to affect the immune status of the host, and potentially, the overall health and growth of the pigs. Ascorbic acid acts as an antioxidant and was expected to maintain cell integrity. Tylosin and beta-glucan plus ascorbic acid treatments have been shown to modulate the immune system, while consumption of carbadox resulted in immune suppression. Tylosin was best able to protect the pig from potential pathogens colonizing the gastrointestinal tract and insuring the health of the pig. Yeast culture alone had immunomodulating properties that may have helped alter the intestinal microbial ecology as well.
Degree
M.S.
Advisors
Patterson, Purdue University.
Subject Area
Animal sciences
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