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The effect of maternal antioxidant nutrient supplementation and age on chick post-hatch innate immune function
- Author / Creator
- Johnson, Melissa L
The chick’s innate immune system may affect post-hatch liveability and performance, but is immature at hatch. The development of the immune system begins in ovo and may be affected by hen age and nutrition. Antioxidants are molecules capable of preventing and correcting oxidative damage and may play an important role in the innate immune response because reactive oxygen species are produced as a bactericidal mechanism. Supplementing hens with antioxidant ingredients may have a priming effect on the chick’s innate immune development and increase the response post-hatch. The objective of this thesis was to investigate how hen age and nutrition affected chick post-hatch innate immunity.
Hens were supplemented with one of the antioxidant ingredients, canthaxanthin, synthetic or natural vitamin E or L-carnitine. At three hen ages: 31-33, 45-47, and 57-59 wks, fertile eggs were incubated and hatched. Whole blood was collected for the determination of innate immune function indices which included Escherichia coli bactericidal capacity (EBC), phagocytosis, oxidative burst and plasma total antioxidant capacity.
The maternal supplementation of each of these three ingredients demonstrated their immuno-modulatory potential in post-hatch chicks. Supplementing with 6 ppm canthaxanthin or natural vitamin E increased chick EBC which was a general measure of innate immune function; while L-carnitine supplementation increased chick oxidative burst. Supplementation of all three ingredients resulted in a three way interaction between hen treatment and age and chick age with respect to chick plasma total antioxidant capacity. The most consistent observation was that chick EBC decreased as hens aged leading to a study investigating the effects of maternal age and incubator temperature on chick innate immune function. Eggs from 26 to 34, 35 to 44 and 45 to 54 wk old hens were incubated at one of four incubator temperatures, 36.0, 36.5, 37.0, or 37.5°C. It was observed that chicks from 26 to 34 wk old hens had greater innate immune responses and that incubating eggs at 36.5°C resulted in the greatest innate immune response. This research supports published data that chick immune function is affected by incubation conditions and strongly suggests that it is greater in chicks from young hens.
- Graduation date
- Spring 2013
- Type of Item
- Doctor of Philosophy
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