Theses and Dissertations

Issuing Body

Mississippi State University


Peebles, David, E.

Committee Member

Pharr, G. Todd

Committee Member

Kidd, Michael

Committee Member

Branton, L. Scott

Committee Member

Cummings, Timothy

Date of Degree


Document Type

Graduate Thesis - Open Access


Poultry Science

Degree Name

Master of Science


College of Agriculture and Life Sciences


Department of Poultry Science


The effects of 6/85-strain M. gallisepticum (6/85MG) inoculation alone or in conjunction with a F-strain M. gallisepticum (FMG) over-lay and its timing on the performance, egg, blood, and visceral characteristics of commercial egg laying hens were investigated. The applied treatments did not affect layer performance, but did affect yolk moisture and fatty acids, liver moisture, and plasma protein. The plasma protein and liver moisture changes may be indicative of the effects of the treatments on the hydration statuses of the birds during lay, whereas alterations in yolk palmitic, oleic, and linolenic acid levels with treatment may have been manifested by disturbances in the desaturation and elongation processes of fatty acid synthesis. Pre-lay 6/85MG inoculations may be a suitable substitute for pre-lay FMG inoculations and FMG overlays during lay on pre-lay 6/85MG inoculations may provide continual protection without eliciting any subsequent suppressive affects on performance.