The ongoing shift from conventional cage to alternative housing for layers necessitates a deeper understanding of how commercial rearing systems impact physical development in pullets. My thesis examined the effect of three styles of rearing aviaries, differing in the opportunities for load-bearing exercise available during early life, and conventional rearing cages on musculoskeletal characteristics and proximate composition in two consecutive flocks of Lohmann Brown Lite (B) and Lohmann Select Leghorn Lite (W) laying hen pullets.
This thesis investigates the effects of increasing fat at the expense of lactose in milk replacer (MR) on growth, voluntary feed intake, feeding behaviour, and blood metabolites in Holstein calves. When investigating the effects high fat MR fed ad libitum, it was found that higher fat inclusion reduced voluntary MR intake without an evident effect on solid feed intake or growth. However, greater fat inclusion reduced hunger-related behaviours during the weaning period.
The Summer Undergraduate Research Showcase happened the week of August 23-27, 2021. Watch the 14 students from across campus showcase their summer research projects in 3-5 minute videos, then attend the live Question & Answer sessions running August 25 and 26, 2021.
The overall objective of this thesis was to determine how milk yield at dry-off in AMS-milked cows, as affected by milking frequency and feed supplement allocation in the AMS, impacted udder health over the dry period, and how those factors might also affect milk production and cow behaviour before dry-off and in the next lactation.
This thesis investigated the impact of complete replacement of inorganic sources of supplementary trace minerals by organic sources in the diet of transition cows on cellular and humoral immunity of dams and neonate calves, colostrum characteristics, and oxidative balance, health and growth of calves. In cows, neu-trophil function was assessed in vitro by flow cytometry assays, and acquired immunity was evaluated by in vivo IgG responses to ovalbumin.
