Factors related to shell deaths during artificial incubation of ostrich eggs

dc.contributor.authorBrand Z.
dc.contributor.authorCloetea S.W.P.
dc.contributor.authorBitown C.R.
dc.contributor.authorMalecki I.A.
dc.date.accessioned2011-05-15T15:56:59Z
dc.date.available2011-05-15T15:56:59Z
dc.date.issued2007
dc.description.abstractThe ostrich industry experiences a high rate of embryonic mortalities during artificial incubation of eggs. Embryonic deaths were studied from data recorded on 37 740 fertile eggs incubated artificially during the 1998-2005 breeding seasons. Roughly 10 000 eggs that sustained embryonic mortalities were classified according to the stage and nature of death, i.e. before 21 days of incubation, after 21 days of incubation, deaths after pipping and rotten eggs. Although infection may have played a role in ∼1300 rotten eggs, no detailed knowledge of the pathogens involved was available. The remainder of deaths could not be related to pathogens and the deaths were thus generally referred to as non-infectious. The overall level of embryonic mortality in all the eggs studied was 28.5 %. Overall embryonic mortality was affected by incubator, with higher levels (57.0 %) found in eggs incubated in an African Incubator® and also in eggs that were transferred between incubators during incubation (38.1 %). Overall embryonic mortality also increased in eggs produced by older females. Eggs produced in the autumn had the highest level of embryonic mortality at 53.6 %, whereas eggs produced in the winter had a marginally higher level of embryonic mortalities of 29.2 % compared with eggs produced during summer (27.4 %). Eggs produced by South African (SA) Black males crossed to Zimbabwean Blue females had high levels of embryonic losses of 45.7 %. The embryonic mortality of eggs produced by SA Blacks or Zimbabwean Blue breeding birds subjected to pure breeding was similar at ∼33-34 %, but embryonic mortality was improved in eggs produced by Zimbabwean Blue males crossed to SA Black females (27 %). Embryonic mortality was increased in eggs that were set directly (32.0 %) or subjected to longer than 6 days of storage (43.5 %). Embryonic mortality was affected by year. The results that were obtained will assist in determining non-infectious factors that have a negative effect on hatching success. Steps can thus be taken to eliminate such factors that may compromise hatching success.
dc.description.versionArticle
dc.identifier.citationJournal of the South African Veterinary Association
dc.identifier.citation78
dc.identifier.citation4
dc.identifier.issn10199128
dc.identifier.urihttp://hdl.handle.net/10019.1/10153
dc.subjectarticle
dc.subjectautumn
dc.subjectbreeding
dc.subjectbreeding line
dc.subjectcontrolled study
dc.subjectcross breeding
dc.subjectegg production
dc.subjectegg shell
dc.subjectembryo
dc.subjectembryo death
dc.subjectembryo mortality
dc.subjectfemale
dc.subjecthatching
dc.subjectincubation time
dc.subjectincubator
dc.subjectmale
dc.subjectmedical record review
dc.subjectnonhuman
dc.subjectostrich
dc.subjectseasonal variation
dc.subjectSouth Africa
dc.subjectstorage
dc.subjectsummer
dc.subjectwinter
dc.subjectZimbabwe
dc.subjectAge Factors
dc.subjectAnimal Husbandry
dc.subjectAnimals
dc.subjectAnimals, Domestic
dc.subjectBird Diseases
dc.subjectBreeding
dc.subjectCrosses, Genetic
dc.subjectFemale
dc.subjectIncubators
dc.subjectMale
dc.subjectRisk Factors
dc.subjectSeasons
dc.subjectStruthioniformes
dc.subjectTime Factors
dc.subjectAves
dc.subjectStruthioniformes
dc.titleFactors related to shell deaths during artificial incubation of ostrich eggs
dc.typeArticle
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