The Effects of Maternal Energy Restriction During Mid-Gestation on Growth Performance, Immune Function, and Gene Expression in the Resultant Beef Offspring

_________________________________________________________ 59 INTRODUCTION _____________________________________________________ 61 MATERIALS & METHODS _____________________________________________ 63 Animals __________________________________________________________ 63 Dietary Treatments _________________________________________________ 63 Cow Measurements _________________________________________________ 65 Blood Sample Collection _____________________________________________ 65 Analysis of Blood Urea Nitrogen _______________________________________ 66 Analysis of Insulin __________________________________________________ 66 Analysis of Non-Esterified Fatty Acids __________________________________ 66 Cow Management Analysis ___________________________________________ 67 Statistical Analysis __________________________________________________ 68 RESULTS ____________________________________________________________ 69 viii DISCUSSION _________________________________________________________ 71 LITERATURE CITED __________________________________________________ 79 CHAPTER III. The influence of maternal energy restriction during mid-gestation on beef offspring growth and feedlot performance _________________________ 87 ABSTRACT __________________________________________________________ 87_________________________________________________________ 87 INTRODUCTION _____________________________________________________ 89 MATERIALS & METHODS _____________________________________________ 91 Animals __________________________________________________________ 91 Cow Management __________________________________________________ 91 Cow Management Analysis ___________________________________________ 91 Postweaning Offspring Management ___________________________________ 92 Statistical Analysis __________________________________________________ 94 RESULTS & DISCUSSION______________________________________________ 96 IMPLICATIONS _____________________________________________________ 106 LITERATURE CITED _________________________________________________ 107 CHAPTER IV. Maternal energy status during mid-gestation affects the immune response in the resultant beef progeny __________________________________ 117 ABSTRACT _________________________________________________________ 117________________________________________________________ 117 INTRODUCTION ____________________________________________________ 119 ix MATERIALS & METHODS ____________________________________________ 121 Animals _________________________________________________________ 121 CowManagement __________________________________________________ 121 Cow Management Analysis __________________________________________ 121 Calf Management __________________________________________________ 122 ELISA Ovalbumin Assay ____________________________________________ 123 Statistical Analysis _________________________________________________ 125 RESULTS & DISCUSSION_____________________________________________ 127 IMPLICATIONS _____________________________________________________ 135 LITERATURE CITED _________________________________________________ 136 CHAPTER V. Maternal energy status during the second trimester of gestation does not alter gene transcription in subcutaneous adipose tissue of the resultant offspring _________________________________________________________________ 141 ABSTRACT _________________________________________________________ 141________________________________________________________ 14