Show simple item record

dc.contributor.authorBourgon, Stephanie
dc.date.accessioned2017-05-11T18:34:52Z
dc.date.available2017-05-11T18:34:52Z
dc.identifier.urihttp://hdl.handle.net/10222/72901
dc.description.abstractFeed efficiency and bull fertility are two major factors affecting profitability of the beef industry. However, there is concern of an antagonistic relationship between these two factors, highlighting the need to clarify the relationship between age, feed efficiency and sexual development. Two experiments were undertaken to evaluate associations of blood parameters and fertility-related measures with age and feed efficiency in yearling bulls. Firstly, 32 bulls were studied and among other results, younger and efficient bulls exhibited lower testosterone and triiodothyronine levels, respectively. Secondly, investigation of 158 bulls revealed that younger bulls had smaller scrotal circumference, higher scrotal radiant heat loss and fewer normal sperm while efficient bulls indicated lower scrotal circumference, scrotal radiant heat loss, and a trend towards lower testicular echogenicity and higher sperm head defects. Metabolic differences associated with variation in feed efficiency may impact reproductive function as illustrated by features of delayed sexual development in efficient bulls.en_US
dc.language.isoenen_US
dc.subjectresidual feed intakeen_US
dc.subjectscrotum thermographyen_US
dc.subjectsemen qualityen_US
dc.subjectsexual developmenten_US
dc.subjecttriiodothyronineen_US
dc.subjecttestes ultrasonographyen_US
dc.subjectBulls
dc.subjectBeef cattle--Breeding
dc.subjectBeef cattle--Feeding and feeds
dc.titleRelationships of blood parameters and fertility-related traits with age and feed efficiency in young beef bullsen_US
dc.typeThesisen_US
dc.date.defence2016-04-28
dc.contributor.departmentFaculty of Agricultureen_US
dc.contributor.degreeMaster of Scienceen_US
dc.contributor.external-examinerN/Aen_US
dc.contributor.graduate-coordinatorDr. Dian L. Pattersonen_US
dc.contributor.thesis-readerDr. Mariana Diel de Amorimen_US
dc.contributor.thesis-readerDr. Alan H. Fredeenen_US
dc.contributor.thesis-supervisorDr. Yuri R. Montanholien_US
dc.contributor.ethics-approvalReceiveden_US
dc.contributor.manuscriptsYesen_US
dc.contributor.copyright-releaseNot Applicableen_US
 Find Full text

Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record