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The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches
Thesis (MScAgric)--Stellenbosch University, 2012.
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| Format: | Thesis |
| Language: | en_ZA |
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Stellenbosch : Stellenbosch University
2012
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| _version_ | 1867613960724807680 |
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| access_status_str | Open Access |
| author | Lorenzen, Jan Frederik George |
| author2 | Hoffman, Louwrens C. |
| author_browse | Hoffman, Louwrens C. Lorenzen, Jan Frederik George |
| author_facet | Hoffman, Louwrens C. Lorenzen, Jan Frederik George |
| author_sort | Lorenzen, Jan Frederik George |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MScAgric)--Stellenbosch University, 2012. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/71714 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA |
| last_indexed | 2026-06-10T12:44:25.612Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2012 |
| publishDateRange | 2012 |
| publishDateSort | 2012 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/71714 The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches Lorenzen, Jan Frederik George Hoffman, Louwrens C. Brand, T. S. Stellenbosch University. Faculty of AgriSciences. Dept. of Animal Sciences. Ostrich meat -- Quality Ostriches -- Transportation Theses -- Agriculture Dissertations -- Agriculture Thesis (MScAgric)--Stellenbosch University, 2012. ENGLISH ABSTRACT: Although transport and lairage of ostriches are accepted causes of production losses, these losses have not yet been quantified. Transport and lairage regulations focus on the wellbeing of the birds and, by default reduce some losses. This thesis investigated weight losses and meat quality of ostriches as a result of transport density, lairage duration and lairage feed availability (ad libitum). All birds were reared on the same farm and loaded and transported together. They were randomly divided into their respective groups on loading for the transport trial, and on offloading for the lairage trial. Bird grouping was according to density for the transport trial (4 groups, H1, H2: 0.56m2/bird and L1, L2: 0.96m2/bird) and according to time spent in lairage and feed availability for the lairage trial (n=30 birds/group; L0hr and L24hr; n=15 birds/group L48hr and L48hr ad libitum feed). Behavioural observations of the ostriches showed a tendency of the ostriches to lean against objects and to orientate towards forces exerted on it to help keep its balance. Reactions to sound fluctuations were noted, with birds reacting towards changes in sound volume during transport and lairage. Timepoint numbers were allocated for each time the birds were weighed during the trial. Time points 1, 2, 3, 4 and 5 were allocated to loading, arrival, 19 hr in lairage, 31 hr in lairage and 39 hr in lairage respectively for Trial 2. Results showed no differences (P > 0.05) in live weights or meat quality parameters between Groups H1, H2, L1 and L2 during transport. Differences (P < 0.05) were found in cumulative weight losses between L0hr and the rest of the groups for time point 1. Differences between L48hr and L48hr ad libitum were found for time point 4 for cumulative weight loss. L48hr also differed significantly between the other lairage duration groups for dressing percentages as a function of loading weight. Ad libitum feed availability had a significant effect on live body weight changes but not the meat quality parameters for the groups held for 48hr in lairage. The number of birds having bruises (≈50% per group) was similar between groups and lairage had no influence on bruising. Results seem to indicate that the evaluated transport densities had no effect on the weight loss or meat quality of ostriches. However, the results indicate that the lairage period should be studied further with specific reference to weight losses during lairage. Meat quality was unaffected by the lairage parameters reported in this thesis. AFRIKAASE OPSOMMING: Hoewel vervoer en voorslag hou (“lairage”) aanvaar word as die oorsake van produksieverliese, is hierdie aspekte nog nie gekwantifiseer nie. Regulasies in terme van vervoer en voorslag hou fokus op die welstand van die voëls en gevolglik verminder sommige verliese met hierdie faktore. Konflik tussen boere en sekondêre produsente (abattoirs en verwerkers) oor die kostes verbonde aan hierdie gewigsverliese, is in wese ‘n oorsaak van oorbruggingsfases (vervoer). Daarom is die voorslag hou-parameters van tyd, voerbeskikbaarheid en laai digtheid ondersoek. Twee proewe is geloods; een vir vervoer en een vir voorslag aanhou. Voëls is voor hulle op vragmotors gelaai is, geweeg en op spesifieke tye daarna geweeg. Diere van die laaidigtheidsproef is ingedeel in vier groepe (H1, H2: 0.56m2/voel en L1, L2: 0.96m2/voel). Met aflaai is die eerste toets groep geslag terwyl die tweede toets groep ingedeel is volgens die tyd gespandeer en voer beskikbaarheid in voorslag aanhou (n=30 voëls/groep - Groepe L0u, L24u; n=15 voëls/groep - L48u en L48u ad libitum gevoer). Gedrag van voëls is aangeteken tydens vervoer. Finale gewig was slagpale gewig en elke tyd periode waar die voëls geweeg is, is aangeteken as ‘n tydpunt. Vleiskwaliteit analises is gedoen op die linker boud se fan filet. ‘n Standaard rak leeftyd toets is ook gedoen om kwaliteit parameters te toets oor tyd. pH is gekatorigiseer volgens groepe om moontlike verskille te beklemtoon. Gedrag is opgeteken volgens die oriëntasie en steunings gewoontes van die volstruise gedurende vervoer. Voëls probeer hulle balans te hou deur op voorwerpe en op mekaar te leun, asook om hul liggaam oriëntasie te gebruik. Reaksies tot klank veranderinge is ook opgemerk tydens vervoer en voorslag aanhou. Resultate toon geen betekenisvolle verkille tussen digtheid groepe H1, H2, L1 en L2 nie. Geen gewigsverskille is gevind tussen vervoerdigtheid groepe nie. Vleiskwaliteit-parameters is ook ondersoek en geen verskille is gevind tussen groepe nie. Resultate toon wel betekenisvolle verskille in gewigsverlies-persentasie tussen groepe vir tyd in voorslag aanhou. Groepe L48u en L48u ad libitum, het onder andere betekenisvol verskille getoon vir tydpunt 4. Betekenisvolle verskille in uitslagpersentasie as funksie van begin-gewig tussen 48 uur en die res van die groepe is ook gevind. Verdere vleiskwaliteit-parameters (drupverlies, pH, ens.) tussen groepe het geen betekenisvolle verskille getoon nie. Resultate dui aan dat voer beskikbaarheid het ‘n invloed op gewigsverskille in voorslag aanhou. Regulasies vir voorslag hou, vervoer en welstand van volstruise sal moontlik verder ondersoek moet word met spesiale klem op die nut van voorslag aanhou en die se invloed op gewigsverlies. Vleiskwaliteits-parameters is nie beïnvloed deur die aspekte ondersoek nie. Masters 2012-11-29T13:02:28Z 2012-12-12T08:09:23Z 2012-11-29T13:02:28Z 2012-12-12T08:09:23Z 2012-12 Thesis http://hdl.handle.net/10019.1/71714 en_ZA Stellenbosch University 101 p. : ill. application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Ostrich meat -- Quality Ostriches -- Transportation Theses -- Agriculture Dissertations -- Agriculture Lorenzen, Jan Frederik George The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches |
| title | The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches |
| title_full | The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches |
| title_fullStr | The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches |
| title_full_unstemmed | The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches |
| title_short | The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches |
| title_sort | effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches |
| topic | Ostrich meat -- Quality Ostriches -- Transportation Theses -- Agriculture Dissertations -- Agriculture |
| url | http://hdl.handle.net/10019.1/71714 |
| work_keys_str_mv | AT lorenzenjanfrederikgeorge theeffectoflairagetimeandtransportdensityonliveweightlossesandmeatqualityinslaughterostriches AT lorenzenjanfrederikgeorge effectoflairagetimeandtransportdensityonliveweightlossesandmeatqualityinslaughterostriches |