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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Faktore wat die oorlewing van volstruiskuikens (Struthio Camelus) verhoog

Janse Van Vuuren, Maryke January 2008 (has links)
Hierdie verhandeling is ‘n samestelling van verskeie studies, elk opgeskryf in die formaat en styl soos vereis deur die Suid-Afrikaanse Vereeniging vir Diereproduksie (South African Society of Animal Science). Hoofstuk 1 is ‘n literatuurstudie bestaande uit ‘n algemene inleiding wat agtergrond oor die studie verskaf en sluit die probleemstelling in, naamlik die swak oorlewing van volstruiskuikens wat onder kunsmatige toestande grootgemaak word. Hoofstukke 2, 3, 4 en 5 bestaan uit die eerste vier studies, waartydens sekere bestuurs-aspekte, wat moontlik oorlewing van volstruiskuikens kan verbeter (nl: populasiedigtheid, tipe vloer-oppervlak, die aanwending van broeipare en die aanwending van peetouers), ondersoek is. Hoofstukke 6, 7, 8 & 9 handel oor studies wat gerig is om voeding meer aanloklik te maak vir volstruiskuikens teneinde voedselinname te stimuleer en sodoende produksie en oorlewing te verbeter (nl: verskaffing van groenvoer, geur van voer, kleur van voer en beligting van voer). Die laaste hoofstuk bestaan uit ‘n algemene gevolgtrekking en aanbevelings. Alhoewel daar gepoog is om herhaling in hoofstukke te beperk, was dit onmoontlik om herhaling van sekere gedeeltes van hoofstukke te voorkom.
22

Individual identification and parentage analysis of Struthio camelus (ostrich) using microsatellite markers.

Essa, Fatima. January 2005 (has links)
Ostrich (Struthio camelus) breeding is a well-developed industry in South Africa. However, successful genetic management has yet to be implemented. Parentage in colony breeding ostriches is unknown, where for a given offspring, a number of possible parents exist. Molecular markers have been extensively used in the livestock industry to resolve parentage issues and are only beginning to be utilized to address the issues of the ostrich industry. The aims of this investigation were to test known microsatellite markers developed for other ostrich subspecies in a South African Black ostrich population, and to further test these markers for their use in individual and parentage identification. DNA was extracted from venous blood obtained from two pair bred families and a colony of 97 individuals. Eleven polymorphic microsatellite markers were tested by PCR amplification of DNA samples followed by multiplexing on polyacrylamide gels to generate DNA fingerprints for each individual. Alleles were sized and quantified and used to create genotypes for each individual. Parentage analysis was performed using exclusion and likelihood methods. Pedigrees were constructed for the families by comparison of genotypes. Breeding statistics were calculated for the colony individuals. Three microsatellite markers did not amplify in this population and one marker was found to be monomorphic in this population. Four of the microsatellite markers that successfully amplified produced anonymous amplification products suggesting a second annealing site in the genome sequence of Blacks. All loci displayed low observed heterozygosities indicative of little genetic variation in this population. For the colony sample, four individuals were not assigned either parent and one female did not contribute any offspring. On average females produced 4.86 ± 2.71 fertile eggs during the sampling period with a coefficient of variation of 55.86%. A total of 79.2% of individuals were assigned paternity and 88.3% were assigned maternity. A greater number of loci are required to improve the power of parentage analysis within breeding flocks incorporating all eggs laid. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
23

The effects of hot-deboning on the physical quality characteristics of ostrich (Struthio camelus) Muscularis gastrocnemius, pars interna and Muscularis iliofibularis

Botha, Sune St.Clair 03 1900 (has links)
Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2005. / The aim of this study was to investigate the effects of hot-deboning (1 h post-mortem) on the shelf-life and the physical meat quality characteristics, including tenderness, pH, purge (%), cooking loss (%), and raw meat colour of vacuum packed ostrich (Struthio camelus var. domesticus) meat cuts from the M. gastrocnemius, pars interna and the M. iliofibularis during post-mortem refrigerated aging for respectively 21 d at 4ºC and 42 d at -3º to 0ºC.
24

Are You Smarter than an Ostrich: Does “Skin in the Game” Influence an Investor’s Portfolio Monitoring Behavior?

Liu, Iris 01 January 2016 (has links)
Abstract In this paper, we examine the behavior of subjects in a mock financial investment experiment to investigate the effects of “skin in the game” and ego utility on hedonic information acquisition decisions. We observe how often subjects “check” their portfolios after given general market returns, and whether conditions impact the existence and magnitude of the ostrich effect – the tendency to avoid information expected to be negative. When considering these experiment conditions as well as subject sex, risk aversion, curiosity, financial literacy and investing experience, we do not find an ostrich effect. We do find that females check their portfolios more often on average than males. Finally, we find that risk-averse people will check their portfolios more often, regardless of market returns or sex.
25

'n Ekonomiese evaluering van volstruisboerdery in die Oudtshoorn-omgewing

Van Zyl, Pieter Luttig 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2001. / ENGLISH ABSTRACR: Approximately 10 years ago South Africa, and specifically the Oudtshoorn region was the only place in the world that supplied ostrich products for the international market. Today, South Africa is only one of several countries with commercial ostrich farming. The largest concentration of ostrich farmers in the world is, however, still in the Oudtshoorn region. Increasing competition, limited possibilities to diversify and the so-called price cost squeeze put the emphasis on aspects such as higher productivity and lower production costs. The profitability of ostrich farming, especially in the Oudtshoorn region, should urgently be determined and evaluated as farmers rely heavily on this venture as an only source of income. Decreases in slaughter realisations and slaughtering numbers have necessarily negative financial implications for the farmers, as well as for the community as a whole. Diversification is often considered strategic to avoiding or minimising risk. However, the possibilities to diversify especially to existing alternatives, have proven limited. One sure solution is to increase productivity of ostrich farming. Production parameters like the number of day-old chicks per female, chick mortality and slaughtering realisations were found to vary considerable providing scope for improvement. It is evident that several factors that determine the generated income lie outside the sphere of influence of the individual ostrich farmer. The large variation in production performances renders the industry risky, especially for farmers with liquidity problems. Two questionnaires as well as group discussion techniques were used to evaluate the economics of ostrich farming. Income and costing budget models were constructed on Microsoft Excel to be able to do calculations to the level of gross margin. A complete representative ostrich-farming unit was constructed to do calculations to the level of net farm income. The budget models were applied to (1) representative ostrich production practices for each of the three phases in the production process of ostrich farming, and (2) the representative ostrich-farming unit. The effect of different critical factors on the gross margin and net farm income of ostrich farming were thereafter evaluated. Different scenarios were also evaluated. The results of these analyses are representative of ostrich farming in the Oudtshoorn region. A computer model was developed whereby ostrich farming can be evaluated economically. This model can also be applied to assist individual farmers with their planning.As no research results exist on the economics of ostrich farming at micro level, several questions regarding the economics of ostrich farming prompted this study. These questions were answered using the above-mentioned computer models. The survival of the ostrich industry in the Oudtshoom region with its limited resources depends on a secure lead in technology which will enable farmers to produce products of higher quality, but also at lower costs than the rest of the world. / AFRIKAANSE OPSOMMING: Sowat 10 jaar gelede was Suid-Afrika, en spesifiek die Oudtshoom-omgewing, die enigste gebied in die wereld wat volstruisprodukte aan die wereldmark verskaf het. Vandag is Suid-Afrika egter een van vele lande waar kommersiele volstruisboerdery voorkom. Die grootste konsentrasie van volstruisboere in die wereld word egter steeds in die Oudtshoom-omgewing aangetref. Toenemende mededinging, beperkte moontlikhede om te diversifiseer en die sogenaamde pryskoste-knyptang impliseer dat aspekte soos hoer produktiwiteit en laer produksiekoste aandag moet geniet. 'n Behoefte bestaan om die winsgewendheid van die volstruisvertakking, spesifiek in die Oudtshoomomgewing, nie net te bepaal nie, maar ook te evalueer. Voistruisboere in die Oudtshoom-omgewing steun swaar op die volstruisvertakking vir die generering van inkomste. 'n Verlaging in slagrealisasies en 'n inkorting van slaggetalle het dus noodwendig negatiewe finansiele implikasies tot gevolg, nie net vir die volstruisboere nie, maar ook vir die hele gemeenskap. 'n Strategie om risiko te vermy, mag wees om te diversifiseer, maar die moontlikhede om te diversifiseer, veral na die bestaande vertakkings wat reeds verbou word, blyk egter beperk te wees. 'n Oplossing kan wees om die produktiwiteit van volstruisboerdery te verhoog, met ander woorde om bestaande dinge beter te doen. Groot variasies kom onder andere voor in die getal dagoudkuikens per wyfie, vrektesyfer onder kuikens en ook slagresultate. Groot ruimte vir verbetering bestaan dus. Dit blyk dan ook dat daar heelwat faktore is wat buite die invloedsfeer van die indiwiduele volstruisboer val wat bepalend is vir die inkomste wat 'n slagvolstruis realiseer. Die groot variasies, soos genoem, impliseer verder dat die risiko van volstruisboerdery hoog kan wees, veral vir volstruisboere met likiditeitsprobleme. Twee vraelysopnames en die groepbesprekingstegniek is gebruik om volstruisboerdery ekonomies te kon evalueer. Inkomste- en kostebegrotingsmodelle is op Microsoft Excel gekonstrueer ten einde berekeninge tot op die vlak van bruto marge te kon doen. 'n Volledige verteenwoordigende volstruisboerdery-eenheid is vervolgens gekonstrueer om berekeninge ook tot op die vlak van netto boerdery-inkomste te kon doen. Die begrotingsmodelle is toegepas op (0 verteenwoordigende volstruisproduksiepraktyke vir elk van die drie fases in die produksieproses van volstruisboerdery en (2) die verteenwoordigende volstruisboerdery-eenheid. Die effek van verskillende kritieke faktore op die bruto marge en netto boerdery-inkomste van volstruisboerdery is vervolgens geevalueer. Verskillende scenarios is ook aan die hand van die verteenwoordigende boerderyeenheid beoordeel. Die resultate van hierdie ontledings is verteenwoordigend van volstruisboerdery in die Oudtshoom-omgewing. 'n Rekenaarmodel is in die proses ontwikkel om volstruisboerdery ekonomies te kan evalueer. Hierdie model kan ook aangewend word om indiwiduele volstruisboere met beplanning te help. Heelwat vrae oor die ekonomie van volstruisboerdery het aanleiding gegee tot die aanvang van hierdie studie. Navorsingsresultate oor die ekonomie van volstruisboerdery op mikrovlak bestaan dan ook nie. Deur gebruik te maak van die genoemde rekenaarmodelle is vrae oor die ekonomie van volstruisboerdery beantwoord. Die enigste behoud van die volstruisbedryf in die Oudtshoom-omgewing, met sy beperkte hulpbronne, is 'n stewige voorsprong in tegnologie om nie net beter nie, maar ook goedkoper as die res van die wereld te produseer.
26

Effect of cottonseed oilcake meal on ostrich growth performance, meat chemical composition and sensory attributes

Schoon, Katryn 12 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: This research study consists of three investigations with regard to ostrich (Struthio camelus var. domesticus) production, meat quality and the processing of ostrich meat into a value added meat product. The first study was conducted in order to establish whether the gradual replacement of soybean oilcake meal with cottonseed oilcake meal (CSOCM) as a protein source in the diet of slaughter ostriches would affect ostrich growth performance and meat quality. A total of 105 ostriches were divided into five feeding groups according to the CSOCM inclusion level: Control (0% CSOCM), 3%, 6%, 9% and 12% CSOCM, and fed with experimental diets from 6 to 13 months of age. As a result of feeding CSOCM, the final live weight and the average daily gain significantly increased in the 12% CSOCM group compared to the other treatment diets. The proximate composition, cholesterol content, mineral and fatty acid profile of the meat remained unaffected. Considering all the results, CSOCM may be used as an alternative protein source to soybean oilcake meal in ostrich nutrition, resulting in decreased feed costs. Secondly, a descriptive sensory analysis, together with chemical and physical measurements, was performed to determine whether the manipulation of the fatty acid composition in the fan fillet (Iliofibularis muscle) as a result of feeding CSOCM would be detected on a sensory level. Two levels of CSOCM were investigated; 0% as a control and 9% CSOCM. No significant differences were found for the physical measurements (cooking loss (%) and shear force) as well as for the pH and proximate composition of the raw fan fillet. The Control group presented a higher (P<0.05) mono-unsaturated fatty acid (MUFA) content in the cooked fan fillet whereas the 9% CSOCM group showed a favourable increased (P<0.05) poly-unsaturated fatty acid (PUFA) content when compared to the cooked Control samples. As a result, the poly-unsaturated:saturated fatty acid (PUFA:SFA) ratio in the 9% CSOCM group was also higher (P<0.05). No differences (P>0.05) were found between the treatments for the n-6:n-3 (omega 6 to omega 3) ratio. The 9% CSOCM group had a more intense beef aroma, had a higher level of initial and sustained juiciness as well as increased tenderness (P<0.05). Inclusion of 9% CSOCM resulted in a favourable cooked ostrich fan fillet. Finally, the effect of feeding CSOCM on a processed ostrich meat product was investigated. Fan fillet (Iliofibularis muscle) from 13 month old birds receiving no cottonseed oilcake meal (Control) or 9% cottonseed oilcake meal (9% CSOCM) was used. Olive oil was used as a replacement for pork fat, and warthog (Phacochoerus africanus) meat was used to replace commercial pork meat in the production of a semi dry sausage, cabanossi. Olive oil was included at three levels (0%, 1% and 2%). Six treatments were investigated: Control 0% olive oil, Control 1% olive oil, Control 2% olive oil, 9% CSOCM 1% olive oil, 9% CSOCM 2% olive oil en 9% CSOCM 2% olive oil. The Control and 9% CSOCM ostrich meat did not differ significantly in chemical composition nor fatty acid profile. After smoking and drying the fat content in the cabanossi containing 0%, 1% and 2% olive oil averaged 7.2%, 7.45% and 8.65% respectively. Processed meat products containing less than 10% fat are classified as a low-fat meat product. Olive oil is a mono-unsaturated vegetable oil containing mainly Oleic acid (C18:1n9c), and low quantities of saturated fatty acids and polyunsaturated fatty acids. Total mono unsaturated fatty acids in the cabanossi increased from 47.0% to 73.0% of total fat, whilst total saturated fatty acids and total polyunsaturated fatty acids decreased from 40.6% to 19.9% and 11.6% to 6.6% respectively as olive oil increased from 0% to 2%. The inclusion of olive oil at 2% resulted in cabanossi with increased (P<0.05) tenderness, juiciness and cured red meat colour, all factors that appeal greatly to the consumer. Overall flavour was not adversely affected by the inclusion of olive oil. This investigation indicated that the use of CSOCM had no negative effect on the production performance of ostriches whilst a 9% CSOCM inclusion level resulted in meat that was found to be favourable by a trained sensory panel. Furthermore, the use of CSOCM as a feed component also had no negative effect on a processed product (cabanossi) derived from the meat obtained from the birds fed this feed component. The CSOCM used in this investigation had low levels of gossypol (10 to 20ppm) and more research is required on the effect of the use of CSOCM with higher levels of gossypol on the production performance of ostriches. / AFRIKAANSE OPSOMMING: Die studie het bestaan uit drie ondersoeke met betrekking tot volstruis (Struthio camelus var. domesticus) -produksie, -vleiskwaliteit en die vervaardiging van waarde-toegevoegde geprosesseerde volstruis-vleisprodukte. Die doel van die eerste studie was om vas te stel of die geleidelike vervanging van sojaboonoliekoekmeel met katoensaad-oliekoekmeel (CSOCM) as ‘n proteïenbron in die voeding van volstruise, die groeipersentasie en vleiskwaliteit van die Iliofibiularis spier (fan fillet) sal affekteer. ‘n Totaal van 105 volstruise is verdeel in vyf voedingsgroepe volgens die katoensaad oliekoekmeel insluitingsvlak: Kontrole (0% CSOCM), 3%, 6%, 9% en 12% CSOCM. Die onderskeie voedingsgroepe was van ses tot 13 maande ouderdom op die eksperimentele voere geplaas. Die resultate het aangedui dat die voëls in die 12% CSOCM behandelingsgroep ‘n betekenisvolle (P<0.05) toename in finale lewende massa asook gemiddelde daaglikse toename gehad het. Die proksimale samestelling, cholesterol-inhoud, mineraal- en vetsuursamestelling van die vleis was nie geaffekteer deur die insluiting van CSOCM nie. Die CSOCM kan dus wel as ‘n alternatiewe proteïenbron in die voeding van volstruise gebruik word. Laasgenoemde bevinding kan ook lei tot verlaagde voerkostes, aangesien CSOCM heelwat goedkoper is as sojaboon-oliekoekmeel. Die tweede deel van die studie was van ‘n chemiese asook sensoriese aard. ‘n Beskrywende sensoriese analiese is uitgevoer om vas te stel of die manipulering van die vetsuursamestelling in die volstruis fan fillet as gevolg van die CSOCM sensories waargeneem kan word. Die chemiese en fisiese eienskappe van die vleis is ook ondersoek. Twee vlakke van CSOCM inhoud is ondersoek; 0% (as kontrole) en 9% CSOCM. Geen betekenisvolle verskille is gevind vir die fisiese vleiskwaliteit (kookverliespersentasie en taaiheid), asook vir die proksimale samestelling en pH van die fan fillet nie. Die gekookte fan fillet van die Kontrole behandeling het ‘n betekenisvolle (P<0.05) toename in mono-onversadigde vetsure (MUFA) getoon en die 9% CSOCM het ‘n voordelige toename in poli-onversadigde vetsuur-inhoud (PUFA) gehad. Die poli-onversadigde tot versadigde vetsuurverhouding (PUFA:SFA) was as ‘n gevolg ook betekenisvol hoër. Geen verskille (P>0.05) is opgemerk in die omega-6 tot omega-3 poli-onversadigde vetsuurverhouding (n-6:n-3) nie. Met betrekking tot die sensoriese eienskappe het die 9% CSOCM ‘n meer opvallende beesvleis aroma, hoër vlakke van aanvanklike sappigheid en ook sagter vleis in vergelyking met die kontrole behandeling gehad (P<0.05). Insluiting van 9% CSOCM het gelei tot ‘n gekookte volstruis fan fillet van voornemende kwaliteit. Laastens is daar ondersoek ingestel op die vervanging van varkvet met olyfolie in die vervaardiging van ‘n volstruis cabanossi. Chemiese asook sensoriese analises is uitgevoer op die gedroogde en gerookte volstruis cabanossi. Vir die vervaardiging van laasgenoemde produkte is die fan fillet van 13 maande oue voëls van die Kontrole (0% CSOCM) en 9% CSOCM behandelings gebruik. Addisioneel tot die volstruisvleis is daar ook vlakvarkvleis (Phacochoerus africanus) gebruik om die kommersiële varkvleis te vervang. Olyfolie was ingesluit teen drie vlakke (0%, 1% en 2% van die totale mengsel). Ses behandelings was ondersoek: Kontrole 0% olyfolie, Kontrole 1% olyfolie, Kontrole 2% olyfolie, 9% CSOCM 1% olyfolie, 9% CSOCM 2% olyfolie en 9% CSOCM 2% olyfolie. Daar was geen verskille (P>0.05) in die chemiese en vetsuursamestellings van die Kontrole en 9% CSOCM volstruisvleis nie. Na die droging en rooksiklus was die gemiddelde vet-inhoud van die 0%, 1% en 2% olyfolie cabanossi monsters onderskeidelik 7.2%, 7.45% en 8.65%. Geprosesseerde vleisprodukte met ‘n vet-inhoud van minder as 10% word in die kommersiële vleisindustrie na lae vet vleisprodukte verwys. Olyfolie is baie ryk aan MUFA, veral Oleïensuur (C18:1n9c) en dit bevat ook lae hoeveelhede SFA en PUFA. Die totale MUFA inhoud in die cabanossi het toegeneem van 47.0% tot 73.0% terwyl die totale SFA en PUFA onderskeidelik afgeneem het van 40.6% tot 19.9% en 11.6% tot 6.6%, met ‘n olyfolie toename van 0% tot 2%. Die insluiting van olyfolie teen 2% het gelei tot ‘n sagter cabanossi wat meer sappig was met ‘n meer opvallende rooi gekuurde vleiskleur, wat almal eienskappe is wat dié produk meer aantreklik maak vir die verbruiker. Hierdie studie het aangedui dat CSOCM geen negatiewe effek gehad het op die produksie van volstruise nie. Volstruisvleis van die behandelingsgroep wat CSOCM teen 9% van die dieet ontvang het, het wel vleis geproduseer wat as aanvaarbaar aanskou was deur ‘n opgeleide sensoriese paneel. Die gebruik van CSOCM as ‘n voerbestandeel het ook geen negatiewe effek gehad op ‘n geprosesseerde produk (cabanossi) gemaak van die volstruisvleis nie. Die CSOCM wat in die huidige studie gebruik is, het baie lae vlakke van gossypol (10 – 20dpm) gehad en verdere ondersoek is noodsaaklik om die effek van CSOCM met hoër vlakke van gossypol op die produksie van volstruise te bevestig.
27

Distribuição anatômica e histológica dos componentes do tecido linfóide ao longo do intestino de avestruz (Struthio camelus) / Anatomic and histhologic distribuition of the lymphoid tissue components in the intestin of ostrich

Saviani, Gisele 25 February 2005 (has links)
O avestruz (Struthio camelus), embora compartilhe de muitas adaptações evolucionárias de outros pássaros, possui algumas características anatômicas relacionadas com o seu tubo digestivo que são únicas, entre as quais podemos citar o cólon que se apresenta maior que o ceco (aparece duplicado) . Há algum tempo esta ave têm sido explorada economicamente, principalmente na alimentação como uma carne alternativa para o consumo humano. O presente trabalho tem como objetivo estudar as estruturas anatômicas e histológicas do intestino ligadas a distribuição do tecido linfóide . No estudo foram utilizados vinte e quatro avestruzes, com idade entre 2 meses e 2,5 anos, sendo animais destinados ao abate. Para a descrição morfológica utilizou-se a metodologia preconizada Bezuindenhout (1986) e o método de rotina para coloração hematoxilina e eosina. Esperamos contribuir na multiplicação de conhecimentos na área da estrutiocultura. / Although the ostrich shares a lot of evolutionary adaptation with other birds, it presents some anatomical characteristics concerning its digestive tube that are unique, like the colon for instance. The ostrich?s colon is bigger than its caecum. The caecum is doubled. The caecum is folded. This bird has been economically exploited, mainly because of its meat as an alternative food for humans. The purpose of the present research is to study the anatomical and histological structures connecting them to the lymphoid tissue distribution. In this study, 24 ostriches between the ages of 2 months and 2 years and a half ? when they?re ready to be slaughtered ? were used. In order to describe the study, the Bezuindenhout methodology and the routine method for printing H. E. and eosine were used.
28

Níveis hormonais em avestruzes (Struthio camelus) machos e correlação com comportamento e características sexuais secundárias / Hormonal levels and its correlation with behavior and sexual characteristics in male ostriches (Struthio camelus)

Silva, Vivian Ferreira da 30 June 2008 (has links)
O presente trabalho avaliou os níveis séricos de testosterona total e de corticosterona em avestruzes machos e os correlacionou com o comportamento (grau de agressividade e presença ou não de kantling) e as características sexuais secundárias (tamanho de bolsa fálica, tipo e intensidade da coloração de canela e bico) dentro e fora do período reprodutivo destas aves. Além disso, foi descrito o ciclo circadiano dos hormônios testosterona e corticosterona de dois avestruzes machos em reprodução. A técnica utilizada para a dosagem hormonal foi a radioimunoensaio, sendo validada a técnica para a espécie em questão. Durante o período de observações e coleta das amostras de soro das aves avaliadas ao longo da estação reprodutiva foi observada diferença estatística (p<0,05) para as variáveis coloração e níveis de testosterona sérica para os animais em reprodução quando comparados com os animais fora do período reprodutivo (3,96 + 0,11 vs. 3,06 + 0,36, 173,48 + 12,26 vs. 63,92 + 14,75ng/ml, respectivamente). Verificaram-se correlações entre grau de agressividade e tamanho de bolsa fálica dentro (r=0,18; p=0,04) e fora (r=0,38; p=0,03) da estação reprodutiva, coloração de bico e canela e tamanho de bolsa fálica em reprodução (r=0,67; p<0,0001) e fora da reprodução (r=0,68; p<0,0001), níveis séricos de testosterona total e tamanho de bolsa fálica em reprodução (r=0,43; p<0,0001) e fora da reprodução (r=0,51; p=0,0028), níveis séricos de testosterona total e coloração de canela e bico em reprodução (r=0,53; p<0,0001) e fora da reprodução (r=0,72; p<0,0001). Foi também observada correlação positiva para a variável kantling e grau de agressividade no período reprodutivo (r=0,29; p<0,0008), níveis séricos de testosterona total e de corticosterona no período reprodutivo (r=0,43; p<0,0015) e entre kantling e coloração de canela e bico no período não reprodutivo (r=0,36; p<0,04) para as aves estudadas. Na segunda parte do experimento 30 avestruzes machos foram classificados em três níveis (nível 1 - aves com maior bolsa fálica, maior grau de agressividade e coloração; nível 2 - aves com tamanho de bolsa fálica mediano, grau de agressividade e de coloração mediano; nível 3 - aves com tamanho de bolsa fálica menor, menor grau de agressividade e coloração menos intensa) e a produção total de ovos, ovos férteis, ovos inférteis, ovos contaminados, ovos com morte embrionária e total de filhotes nascidos vivos de cada grupo foi analisado estatisticamente, observando-se que as aves pertencentes ao nível 1 obtiveram os melhores índices para as variáveis de produção total de ovos, ovos férteis e total de filhotes nascidos vivos em relação as aves pertencentes ao nível 3. Os resultados do presente experimento descrevem a existência da relação entre os níveis séricos de testosterona e as características sexuais de avestruzes, tais como tamanho de bolsa fálica e grau de coloração, além de descrever a existência de uma relação entre as características sexuais reprodutivas e comportamentais de avestruzes machos e alguns dos seus índices de produção. / The present study evaluated the levels of total serum testosterone and corticosterone in male ostriches and to correlate those values with the behavioral (degree of aggressiveness and presence or not of kantling) and the secondary sexual characteristics (cloacal size, type and intensity of the color of the peak and cinnamon) during the reproductive and non-reproductive seasons of these birds. Moreover, the circadian cycle of the hormones testosterone and corticosterone of two male ostriches in reproduction was described. The technique used for the hormonal assay was the radioimmunoassay, which was validated for the specie. During the period of observations and serum samples collection, differences (p<0,05) were found on color and serum levels of testosterone when comparing the reproductive and non-reproductive seasons (3.96 ± 0.11 vs. 3.06 ± 0.36 and 173.48 ± 12.26 vs. 63.92 ± 14.75, respectively). Correlations were found between aggressiveness and cloacal size during the reproductive (r=0.18; p=0.04) and non-reproductive (r=0.38; p=0.03) seasons, coloration of peak and cinnamon and cloacal size during the reproductive (r=0.67; p<0.0001) and non-reproductive seasons (r=0.68; p<0.0001), levels of total serum testosterone and cloacal size during the reproductive (r=0.43; p<0.0001) and non-reproductive season (r=0.51; p=0.0028), serum levels of testosterone and coloration of cinnamon and peak during the reproductive (r=0.53; p<0.0001) and non-reproductive (r=0.72; p<0.0001). Also positive correlations were observed between kantling and aggressiveness in the reproductive period (r=0.29; p<0.0008), serum level of testosterone and corticosterone in the reproductive period (r=0.43; p<0.0015) and between kantling and color of cinnamon and peak in the non-reproductive period (r=0.36; p<0.04) for the ostriches of the experiment. In the second part of the experiment 30 male ostriches were classified in three levels (level 1 - birds with bigger cloacal size, bigger degree of aggressiveness and coloration; level 2 - birds with medium cloacal size, medium degree of aggressiveness and coloration; level 3 - birds with smaller cloacal size, smaller degree of aggressiveness and less intense coloration) and the total production of eggs, fertile eggs, infertile eggs, contaminated eggs, eggs with embryonic death and total living chicks. Birds from level 1 showed the best indexes for total egg production, fertile eggs and total living chicks in comparative to the birds of the level 3. The results of the present experiment indicated the existence of a relation between the serum levels of testosterone and the sexual characteristics of ostriches, such as cloacal size and degree of coloration, beyond describing the existence of a relation between the secondary sexual characteristics and behavior of male ostriches and some of its indices of production.
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Estudo do membro pélvico do avestruz: considerações anatômicas, radiográficas e histológicas da rotação tibiotársica / Study of hind limb in ostrich: anatomical, radiografic and histological considerations of the tibiotarsica rotation

Oliveira, Roselaine Ponso de 11 March 2005 (has links)
Várias doenças músculo esqueléticas foram observadas em aves de rápido crescimento, sendo o elevado peso corporal, associado a uma estrutura óssea em formação, citados como as principais causas responsáveis pela ocorrência destas doenças, resultando em disfunções do aparelho locomotor. Apesar do estudo do membro pélvico do avestruz merecer a atenção de pesquisadores desde o século XIX, tendo sido descrito no tocante à miologia, principalmente, a osteologia e o estudo radiográfico e morfológico envolvidos na RTT ainda não receberam a devida atenção. O presente trabalho teve como objetivo fazer um estudo anátomo-patológico e radiográfico das estruturas envolvidas na rotação tibiotársica, assim como estudar as alterações articulares através de artrografias e histologia fazendo uma descrição das considerações anatômicas, macroscópicas, microscópicas e radiográficas do membro pélvico do avestruz (African Black). Para este estudo foram utilizadas trinta avestruzes, com idade entre um mês a um ano de idade, apresentando deformidade de membros pélvicos uni ou bilateral. Dessa forma, será possível contribuir para o entendimento desta enfermidade, que tem causado perdas para a estrutiocultura. / Ostrich?s hind limbs study: Anatomical, radiographic and histological considerations of the tibiotarsus rotation. Many skeletal muscles diseases were observed in fast growth, been the hight body wight, to associate with a bone structure in formation citads with the principal responsible cases for ocorrence these deseases, have been disfunction of locomotor arrangment. Despite the fact that the ostrich?s hind limbs have deserved attention from researchers since the 19th century, the myological and osteological descriptions together with the radiographic and morphological study, which involves RTT, have not received any attention yet. This present research intends to make an anatomical, pathological and radiographic study of the structures involved in the tibiotarsus rotation, besides the study of the joint alterations by arthrography and histology, giving one description with anatomical, macroscopic, microscopic and radiographic considerations of the ostrich?s hind limbs. This way, it?ll be possible to contribute to the comprehension of this disease that has caused many losses on the ostrich farm.
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Análise ultrassonográfica, comportamental e produtiva dos efeitos do tratamento com análogo de GnRH em fêmeas de avestruz (Struthio camelus) / Ultrasound, behavioral and productive analysis of the effects of GnRH analog treatment in female ostriches (Struthio camelus)

Silva, Guilherme Costa de Oliveira e 30 July 2012 (has links)
A falta de conhecimento sobre a reprodução do avestruz dificulta o desenvolvimento da sua criação comercial devido a uma baixa eficiência reprodutiva. O objetivo deste estudo foi avaliar a ação da aplicação de um análogo de GnRH (lecirelina - Gestran Plus®) na indução da ovulação em fêmeas adultas de avestruz. Primeiramente, um grupo de 10 fêmeas foi avaliado para determinação de seu status reprodutivo, por meio da mensuração das concentrações séricas de estradiol e progesterona (coletas de sangue 3x/semana); da observação do comportamento reprodutivo; da determinação do desenvolvimento ovariano por exame ultrassonográfico (a cada 21 dias); e pela postura de ovos. Após o término desta primeira fase, as fêmeas foram separadas em grupo controle (n = 3) e grupo tratado (n = 6). A cada semana, 2 fêmeas do grupo tratado eram selecionadas para a aplicação intramuscular de 1ml (25&#956;l) de lecirelina, e os seus efeitos avaliados pela análise das concentrações séricas de estradiol, progesterona e corticosterona (0h, 6h, 24h, 48h e 96h pós-aplicação); pela verificação do desenvolvimento ovariano e ocorrência de ovulação através de exames ultrassonográficos (24h, 48h e 96h); pela observação de comportamento reprodutivo (0h, 48h e 96h) e pela postura de ovos. O tratamento foi repetido no mesmo animal a cada 21 dias e em cada tratamento realizado, 2 fêmeas do grupo controle eram submetidas às mesmas análises. Os resultados indicam que a aplicação de lecirelina foi capaz de induzir a ovulação em 77% dos tratamentos realizados, com postura de ovos normais em 50% das induções. Assim, o tratamento proposto foi considerado eficiente na indução da ovulação em fêmeas de avestruz desde que seja aplicado em fêmeas que apresentem ovário bem desenvolvido. / The lack of knowledge about the ostrich reproduction delays the development of the ostrich commercial breeding due to a low reproductive performance. The aim of this study was to evaluate the effect of the application of an analog of GnRH (Lecirelin - Gestran Plus®) for induction of ovulation in adult female ostriches. Initially, a group of 10 adult female ostriches were evaluated in order to determine their reproductive status, by measuring serum levels of estradiol and progesterone (blood sampling - 3 times a week), by the observation of reproductive behavior, by the evaluation of the ovarian development through ultrasound examination (repeated every 21 days) and by the egg laying data. After the end of the first phase, female ostriches were separated into a control group (n = 3) and a treated group (n = 6). Every week, two females from the treated group were selected to receive the treatment: an intramuscular application of 1 ml (25&#956;l) of Lecirelin. The effect of the application was evaluated by the analysis of serum concentrations of estradiol, progesterone and corticosterone (0h, 6h, 24h, 48h and 96h post-application), by the verification of the ovarian development and the occurrence of ovulation through ultrasound examinations (24h, 48h and 96h), by the observation of reproductive behavior (0h, 48h and 96h) and by the egg laying data. The intramuscular application was repeated in the same animal every 21 days and two females from the control group were subjected to the same analysis during each treatment. The results indicate that the application of Lecirelin was able to induce ovulation in 77% of the treatments with normal egg laying in 50% of inductions. Thus, the treatment was found effective in inducing ovulation in female ostrich provided that it is applied in females who exhibit well developed ovary.

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