• Login
    View Item 
    •   Home
    • Massey Documents by Type
    • Theses and Dissertations
    • View Item
    •   Home
    • Massey Documents by Type
    • Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Lameness of dairy cattle : factors affecting the mechanical properties, haemorrhage levels, growth and wear rates of bovine claw horn : a thesis presented in partial fulfilment of the requirements of a doctoral degree in Animal Science, Massey University, Palmerston North, New Zealand

    Icon
    View/Open Full Text
    02_whole.pdf (681.1Kb)
    01_front.pdf (76.54Kb)
    Abstract
    Lameness is one of the main economic and welfare issues faced by the global dairy industry. It mainly affects the hind claws and the main causes / types are; claw horn lesions of the sole and white line (WL), along with foot rot (NZ) and digital dermatitis (UK). This thesis aims to apply and develop mechanical tests to determine the effect of dietary supplements, animal breed and number of days postpartum (dpp) on claw horn (CH) mechanical properties. Supplementation with live yeast (UK) significantly increased the puncture resistance (PR) of sole horn (P<0.05), level of mean sole haemorrhage percentage, total combined lesion score (TLS) and wear rates (P<0.10), while increasing daily mean milk yield, total milk fat and protein without significant increases in feed intake, providing an increase in feed conversion efficiency. In growing (NZ) dairy cattle PR was lower in 1, 2 (WL) compared with sole (4 and 5) while zones 4 and 5 did not differ significantly. Dairy breed (NZ) affected the PR of the CH, significantly (P<0.001) lower PR in CH of Friesian (all 5 IFM regions) compared with Friesian X Jersey (FxJ). Lactating dairy heifers (partition 22 to 24 months) from 0 to 160 d pp showed that the breed did not significantly affect the; number, percentage or TLS of sole or WL lesions, with the exception of 160 dpp where Friesian heifers had significantly (P<0.05) higher WL and sole lesions compared with FxJ. Mechanical properties (PR) of CH, declined significantly with increasing number of days post partum (dpp), while EM was significantly stiffer at 30 d pp compared with 120 dpp. PR was reduced significantly by increasing lesion score (LS), but was not confirmed by Vickers hardness and EM results. Hydration of CH significantly lowered EM compared to dried horn or horn at physiological moisture content. Short term (200 d), neither the form (zinc as salt or complexes with yeast) not level of zinc (At 1.0 or at 0.3 of NRC recommended levels (RL)) did not significantly affect; locomotion score; growth and wear rates; claw measurements and sole and WL lesions were not significantly effected by form or level of supplemental zinc up to 150 d pp. Overall, the number of days pp (dpp) significantly increased the level of sole and WL lesions, and reduced CH PR and elastic modulus (EM).
    Date
    2009
    Author
    Lethbridge, Louise Anne
    Rights
    The Author
    Publisher
    Massey University
    URI
    http://hdl.handle.net/10179/3072
    Collections
    • Theses and Dissertations
    Metadata
    Show full item record

    Copyright © 2018 Massey University
    Contact Us | Send Feedback | Copyright Take Down Request
    DSpace software copyright © Duraspace
    v5.7-14.09.11
     

     

    Tweets by @Massey_Research
    Information PagesContent PolicyDepositing content to MROCopyright and Access InformationDeposit LicenseDeposit License SummaryTheses FAQFile Formats

    Browse

    All of MROCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister

    Statistics

    View Usage Statistics

    Copyright © 2018 Massey University
    Contact Us | Send Feedback | Copyright Take Down Request
    DSpace software copyright © Duraspace
    v5.7-14.09.11