Project Number: 5438-31000-091-02
Project Type: Trust

Start Date: Dec 15, 2012
End Date: Dec 15, 2013

Objective:
The overall objective of this project is to determine the dietary energy and protein that is optimal for gilt development.

Approach:
This project will be done in collaboration with a commercial collaborator (Murphy Brown), scientists at University of Nebraska-Lincoln and Clemson University. The experiment is designed as a 2 x 3 factorial with two levels of lysine (limiting amino acid) and three levels of metabolizable energy, which have been set by the National Pork Board. Each dietary treatment will be provided to 200 gilts from day 100 of age until day 260 of age. Feed intakes will be measured on a pen basis. Gilts will be weighed and ultrasounded at 4 week intervals. Boar exposure and estrus detection will begin at 160 days of age and age at puberty, number of cycles and cycle length will be recorded. At 260 days of age, gilts will be slaughtered at one or more Farmland plants and reproductive tracts will be assessed for proper development and uterine lengths will be measured. A sample of mammary gland tissue will be collected at slaughter for proximate analysis. A subset (1 out of every tenth gilt) will be processed for ovarian, uterine and mammary gland histological assessment. A sample of uterus from each gilt will be collected for DNA isolation. Data will be used to validate genetic markers for puberty that were discovered at USMARC and University of Nebraska-Lincoln. In addition, data collected will provide phenotypic data for Illumina Swine beadchip genomic analysis for puberty, growth traits, and uterine length.