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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.
11

The natural history of periodontal disease in beagle dogs gingival inflammation, debris, birfurcation [sic] involvement, and roentgenographic bone loss : thesis submitted in partial fulfillment ... periodontics ... /

Grove, Thomas K. January 1975 (has links)
Thesis (M.S.)--University of Michigan, 1975.
12

Properties of flow through the ascending aorta in boxer dogs with mild aortic stenosis momentum, energy, Reynolds number, Womersley's, unsteadiness parameter, vortex shedding, and transfer function of oscillations from aorta to thoracic wall /

da Cunha, Daise Nunes Queiroz, January 2009 (has links)
Thesis (Ph. D.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 113-121).
13

Efeito da contaminação na qualidade do sêmen do tambaqui (Colossoma macropromum) / Effect of contamination in semen quality of tambaqui

Gracia, Luis Fernando Guerrero January 2013 (has links)
O objetivo deste estudo foi avaliar a qualidade do sêmen fresco e congelado de tambaqui (Colossoma macropomum), submetido à contaminação com diferentes fontes. O estudo foi conduzido na região da amazônia brasileira, estado de Rondônia, durante fevereiro e março de 2012. Foram utilizadas amostras de sêmen de 13 machos, divididas em quatro tratamentos: controle (sem contaminante) e contaminado com 10% de urina, sangue ou fezes. Foram avaliadas a motilidade e tempo de duração da motilidade espermática das amostras frescas, e motilidade, integridade de membrana, integridade de DNA, e funcionalidade de mitocôndria das amostras congeladas. A motilidade do sêmen fresco não diferiu (P<0,05) entre as amostras contaminadas por sangue, urina ou fezes (79,6; 76,1 e 78,8%, respectivamente) mas foi inferior em relação ao grupo controle (96,1%). Já nas amostras congeladas, não houve diferença (P>0,05) na motilidade entre as amostras contaminadas com sangue, urina ou fezes (11,1; 22,3 e 34,6%, respectivamente) e as amostras sem contaminantes (40,8%). O tempo de duração da motilidade das amostras, fresco, sem contaminantes (125,5 s) foi superior (P<0,05) ao das amostras contaminadas com sangue ou fezes (85,7 e 77,0 s, respectivamente), e as contaminadas com urina (98,7 s) não diferiram dos outros tratamentos. Os tratamentos contaminados com urina ou fezes (94,0 e 102,5 s, respectivamente) não diferiram (P>0,05) entre si ou em relação aos demais tratamentos. Para a análise de integridade de membrana, os valores 72,4; 77,0 e 68,0% obtidos no sêmen contaminado com sangue, urina e fezes, respectivamente, foram menores (P<0,05) que o controle cuja média foi 91,5%. O tratamento contaminado com urina foi inferior (P<0,05) ao tratamento controle para a integridade de DNA (82,8 e 93,4%, respectivamente) e para a funcionalidade de mitocôndrias (87,1% e 94,9%, respectivamente). Assim, a qualidade seminal é prejudicada com a inclusão dos contaminantes testados (fezes, urina ou sangue), em concentração de 10%, para a maioria dos parâmetros avaliados. / The objective was to evaluate the quality of fresh and thawed semen of C. macropomum, subject to contamination from various sources. The study was conducted in the Brazilian Amazon region, state of Rondônia, during February and March of 2012. Semen samples of 13 males were divided into four treatments: control (no contaminants) and 10% contaminated with urine, blood or feces. Motility was evaluated in fresh and thawed samples whereas membrane integrity, DNA integrity, and functionality of mitochondria were evaluated in thawed samples. The motility of fresh semen was lower (P <0.05) in samples contaminated by blood, urine or feces (79.6, 76.1 and 78.8%, respectively) when compared with control group (96.1%), but did not differ among them. However in post thawed samples, motility was similar (P> 0.05) in samples contaminated with blood, urine or feces (11.1, 22.3 and 34.6%, respectively) compared to samples without contaminants (40.8%). In post thawed semen, only blood contaminated semen (71.2 s) was lower than the control treatment (140.8 s). Treatments contaminated with urine or feces (94.0 and 102.5 s, respectively) did not differ (P> 0.05) among themselves or with respect to other treatments. For the membrane integrity analysis, values of 72.4, 77.0 and 68.0% obtained in semen contaminated with blood, urine and feces, respectively, were lower (P <0.05) than the control whose average was 91.5%. Treatment contaminated with urine was lower (P <0.05) than the control treatment for DNA integrity (82.8 and 93.4%, respectively) and mitochondria functionality (87.1% and 94.9%, respectively). Therefore, most parameters of semen quality were impaired by the inclusion of contaminants tested (feces, urine or blood) at a concentration of 10%.
14

Terra, raça, classe e estratégia / Tierra, raza, clase y estrategia

Souza, Raumi Joaquim de 18 April 2017 (has links)
Submitted by RAUMI JOAQUIM DE SOUZA null (raumibahia@gmail.com) on 2018-05-11T01:52:07Z No. of bitstreams: 1 Raumi Joaquim de Souza - Terra, Raça, Classe e Estratégia.pdf: 659654 bytes, checksum: 6a358c97c4a3a22eb8dc59b9adf68e2b (MD5) / Approved for entry into archive by GRAZIELA HELENA JACKYMAN DE OLIVEIRA null (graziela@ippri.unesp.br) on 2018-05-11T17:56:56Z (GMT) No. of bitstreams: 1 souza_rj_me_ippri_int.pdf: 659654 bytes, checksum: 6a358c97c4a3a22eb8dc59b9adf68e2b (MD5) / Made available in DSpace on 2018-05-11T17:56:56Z (GMT). No. of bitstreams: 1 souza_rj_me_ippri_int.pdf: 659654 bytes, checksum: 6a358c97c4a3a22eb8dc59b9adf68e2b (MD5) Previous issue date: 2017-04-18 / A presente investigação intitulada “Terra, Raça, Classe e Estratégia” visa compreender qual a relação da luta do MST pela Reforma Agrária com o debate sobre a questão racial. Partindo das contribuições teóricas dos sociólogos Clóvis Moura e Florestan Fernandes entre outros autores, nosso estudo tem como finalidade levantar subsídios para a percepção de como as desigualdades sociais e territoriais no campo estão intrinsicamente ligadas às desigualdades raciais. No nosso estudo investigaremos de que maneira o MST historicamente pensa a questão racial associada a luta pela Reforma Agrária, visto que a maioria das pessoas que compõem os assentamentos e acampamentos são negros e negras. A partir desse diagnóstico visamos compreender de que maneira a estratégia de luta do MST se associa à luta contra o racismo, como legado da escravidão e do latifúndio no Brasil. Na perspectiva de contextualizar esta análise em sua possível efetivação nas esferas individual e coletiva, analisaremos a possibilidade de encontrar elementos que apontem para a relação entre terra, raça e classe do ponto de vista da contribuição para o avanço da luta da classe trabalhadora. O estudo parte da hipótese de que o MST não desenvolveu o debate sobre a questão racial como avançou no debate sobre a questão de gênero e a questão LGBT. Porém, constatamos nas entrevistas com militantes do MST da Bahia, um grande potencial para que o debate avance internamente na organização. Pois compreendemos que a questão agrária e a questão racial estão articuladas historicamente no Brasil, sendo marcas do trauma da colonização e da escravidão, que legaram ao país um sistema de divisão da terra desigual e uma estrutura racial que vitimizam a maioria da população pobre e negra com o racismo, como marca estruturante da desigualdade social brasileira. Portanto, podemos tratar a luta pela terra também como uma luta pela superação do racismo, bem como da questão racial como pauta de debate na luta pela reforma agrária. / The present research entitled "Land, Race, Class and Strategy" aims to understand the relationship between the MST struggle for Agrarian Reform and the debate on the racial phenomenon. Starting from the theoretical contributions of sociologists Clóvis Moura and Florestan Fernandes among other authors, our study has the purpose of raising subsidies for the perception of how social and territorial inequalities in the field are intrinsically linked to racial inequalities. In our study we will investigate how the MST historically thinks the racial issue associated with the struggle for Agrarian Reform, since most of the people who make up the settlements and camps are Black and Brown. From this diagnosis we aim to understand how the MST's strategy of struggle is associated with the fight against racism, as a legacy of slavery and latifundia in Brazil. In the perspective of contextualizing this analysis in its possible realization in the individual and collective spheres, we will analyze the possibility of finding elements that point to the relation between land, race and class from the point of view of the contribution to the advancement of the struggle of the working class. The Study starts from the hypothesis that the MST did not develop the debate on the racial issue as it advanced in the debate on the issue of gender and the LGBT question. However, we verified in interviews with militants of the MST of Bahia, a great potential for the debate to advance internally in the organization. For we understand that the agrarian question and the racial question are historically articulated in Brazil, being the marks of the trauma of colonization and slavery, which left the country with a system of uneven land division and a racial structure that victimize the majority of the poor and Black with racism, as a structuring mark of Brazilian social inequality. Therefore we can treat the struggle for land, as well as a struggle to overcome racism, as well as a racial issue as a debate in the struggle for agrarian reform. / Esta investigación titulado "Tierra, raza, clase y Estrategia", que tiene como objetivo comprender la relación de la lucha del MST por la reforma agraria con el debate sobre el fenómeno racial.Sobre la base de las contribuciones teóricas de los sociólogos Clóvis Moura y Florestan Fernandes, entre otros, nuestro estudio tiene como objetivo aumentar los subsidios para la percepción de cómo las desigualdades sociales y territoriales en el campo están intrínsecamente ligadas a las desigualdades raciales. En nuestro estudio vamos a investigar cómo el MST pensar históricamente el problema de la raza asociada con la lucha por la reforma agraria, ya que la mayoría de las personas que conforman los asentamientos y campamentos son hombres y mujeres de raza negra. Con este diagnóstico se pretende entender cómo la estrategia de lucha MST se asocia con la lucha contra el racismo como un legado de la esclavitud y el latifundio en Brasil. Con el fin de contextualizar este análisis de su posible eficacia en las esferas individuales y colectivas, vamos a examinar la posibilidad de encontrar elementos que apuntan a la relación entre la tierra, la raza y el punto de vista de la contribución clase para el avance de la lucha obrera. El estudio parte de la hipótesis de que el MST no se ha desarrollado el debate sobre la raza a medida que avanzaba en el debate sobre la cuestión de la cuestión de género y LGTB.Sin embargo, encontramos las entrevistas a militantes del MST Bahía, un gran potencial para el debate proceder internamente en la organización. Porque entendemos que la cuestión agraria y la cuestión racial se articulan históricamente en Brasil, marcas de trauma de colonización y la esclavitud, que legó al país un sistema de división de un terreno irregular y un marco racial que victimiza a la mayoría de los pobres y el racismo negro como la marca estructuración de la desigualdad social brasileña. Así podemos tratar la lucha por la tierra, así como por la superación de la lucha contra el racismo, así como la cuestión racial como una agenda para la discusión en la lucha por la reforma agraria.
15

Efeito da contaminação na qualidade do sêmen do tambaqui (Colossoma macropromum) / Effect of contamination in semen quality of tambaqui

Gracia, Luis Fernando Guerrero January 2013 (has links)
O objetivo deste estudo foi avaliar a qualidade do sêmen fresco e congelado de tambaqui (Colossoma macropomum), submetido à contaminação com diferentes fontes. O estudo foi conduzido na região da amazônia brasileira, estado de Rondônia, durante fevereiro e março de 2012. Foram utilizadas amostras de sêmen de 13 machos, divididas em quatro tratamentos: controle (sem contaminante) e contaminado com 10% de urina, sangue ou fezes. Foram avaliadas a motilidade e tempo de duração da motilidade espermática das amostras frescas, e motilidade, integridade de membrana, integridade de DNA, e funcionalidade de mitocôndria das amostras congeladas. A motilidade do sêmen fresco não diferiu (P<0,05) entre as amostras contaminadas por sangue, urina ou fezes (79,6; 76,1 e 78,8%, respectivamente) mas foi inferior em relação ao grupo controle (96,1%). Já nas amostras congeladas, não houve diferença (P>0,05) na motilidade entre as amostras contaminadas com sangue, urina ou fezes (11,1; 22,3 e 34,6%, respectivamente) e as amostras sem contaminantes (40,8%). O tempo de duração da motilidade das amostras, fresco, sem contaminantes (125,5 s) foi superior (P<0,05) ao das amostras contaminadas com sangue ou fezes (85,7 e 77,0 s, respectivamente), e as contaminadas com urina (98,7 s) não diferiram dos outros tratamentos. Os tratamentos contaminados com urina ou fezes (94,0 e 102,5 s, respectivamente) não diferiram (P>0,05) entre si ou em relação aos demais tratamentos. Para a análise de integridade de membrana, os valores 72,4; 77,0 e 68,0% obtidos no sêmen contaminado com sangue, urina e fezes, respectivamente, foram menores (P<0,05) que o controle cuja média foi 91,5%. O tratamento contaminado com urina foi inferior (P<0,05) ao tratamento controle para a integridade de DNA (82,8 e 93,4%, respectivamente) e para a funcionalidade de mitocôndrias (87,1% e 94,9%, respectivamente). Assim, a qualidade seminal é prejudicada com a inclusão dos contaminantes testados (fezes, urina ou sangue), em concentração de 10%, para a maioria dos parâmetros avaliados. / The objective was to evaluate the quality of fresh and thawed semen of C. macropomum, subject to contamination from various sources. The study was conducted in the Brazilian Amazon region, state of Rondônia, during February and March of 2012. Semen samples of 13 males were divided into four treatments: control (no contaminants) and 10% contaminated with urine, blood or feces. Motility was evaluated in fresh and thawed samples whereas membrane integrity, DNA integrity, and functionality of mitochondria were evaluated in thawed samples. The motility of fresh semen was lower (P <0.05) in samples contaminated by blood, urine or feces (79.6, 76.1 and 78.8%, respectively) when compared with control group (96.1%), but did not differ among them. However in post thawed samples, motility was similar (P> 0.05) in samples contaminated with blood, urine or feces (11.1, 22.3 and 34.6%, respectively) compared to samples without contaminants (40.8%). In post thawed semen, only blood contaminated semen (71.2 s) was lower than the control treatment (140.8 s). Treatments contaminated with urine or feces (94.0 and 102.5 s, respectively) did not differ (P> 0.05) among themselves or with respect to other treatments. For the membrane integrity analysis, values of 72.4, 77.0 and 68.0% obtained in semen contaminated with blood, urine and feces, respectively, were lower (P <0.05) than the control whose average was 91.5%. Treatment contaminated with urine was lower (P <0.05) than the control treatment for DNA integrity (82.8 and 93.4%, respectively) and mitochondria functionality (87.1% and 94.9%, respectively). Therefore, most parameters of semen quality were impaired by the inclusion of contaminants tested (feces, urine or blood) at a concentration of 10%.
16

Efeito da contaminação na qualidade do sêmen do tambaqui (Colossoma macropromum) / Effect of contamination in semen quality of tambaqui

Gracia, Luis Fernando Guerrero January 2013 (has links)
O objetivo deste estudo foi avaliar a qualidade do sêmen fresco e congelado de tambaqui (Colossoma macropomum), submetido à contaminação com diferentes fontes. O estudo foi conduzido na região da amazônia brasileira, estado de Rondônia, durante fevereiro e março de 2012. Foram utilizadas amostras de sêmen de 13 machos, divididas em quatro tratamentos: controle (sem contaminante) e contaminado com 10% de urina, sangue ou fezes. Foram avaliadas a motilidade e tempo de duração da motilidade espermática das amostras frescas, e motilidade, integridade de membrana, integridade de DNA, e funcionalidade de mitocôndria das amostras congeladas. A motilidade do sêmen fresco não diferiu (P<0,05) entre as amostras contaminadas por sangue, urina ou fezes (79,6; 76,1 e 78,8%, respectivamente) mas foi inferior em relação ao grupo controle (96,1%). Já nas amostras congeladas, não houve diferença (P>0,05) na motilidade entre as amostras contaminadas com sangue, urina ou fezes (11,1; 22,3 e 34,6%, respectivamente) e as amostras sem contaminantes (40,8%). O tempo de duração da motilidade das amostras, fresco, sem contaminantes (125,5 s) foi superior (P<0,05) ao das amostras contaminadas com sangue ou fezes (85,7 e 77,0 s, respectivamente), e as contaminadas com urina (98,7 s) não diferiram dos outros tratamentos. Os tratamentos contaminados com urina ou fezes (94,0 e 102,5 s, respectivamente) não diferiram (P>0,05) entre si ou em relação aos demais tratamentos. Para a análise de integridade de membrana, os valores 72,4; 77,0 e 68,0% obtidos no sêmen contaminado com sangue, urina e fezes, respectivamente, foram menores (P<0,05) que o controle cuja média foi 91,5%. O tratamento contaminado com urina foi inferior (P<0,05) ao tratamento controle para a integridade de DNA (82,8 e 93,4%, respectivamente) e para a funcionalidade de mitocôndrias (87,1% e 94,9%, respectivamente). Assim, a qualidade seminal é prejudicada com a inclusão dos contaminantes testados (fezes, urina ou sangue), em concentração de 10%, para a maioria dos parâmetros avaliados. / The objective was to evaluate the quality of fresh and thawed semen of C. macropomum, subject to contamination from various sources. The study was conducted in the Brazilian Amazon region, state of Rondônia, during February and March of 2012. Semen samples of 13 males were divided into four treatments: control (no contaminants) and 10% contaminated with urine, blood or feces. Motility was evaluated in fresh and thawed samples whereas membrane integrity, DNA integrity, and functionality of mitochondria were evaluated in thawed samples. The motility of fresh semen was lower (P <0.05) in samples contaminated by blood, urine or feces (79.6, 76.1 and 78.8%, respectively) when compared with control group (96.1%), but did not differ among them. However in post thawed samples, motility was similar (P> 0.05) in samples contaminated with blood, urine or feces (11.1, 22.3 and 34.6%, respectively) compared to samples without contaminants (40.8%). In post thawed semen, only blood contaminated semen (71.2 s) was lower than the control treatment (140.8 s). Treatments contaminated with urine or feces (94.0 and 102.5 s, respectively) did not differ (P> 0.05) among themselves or with respect to other treatments. For the membrane integrity analysis, values of 72.4, 77.0 and 68.0% obtained in semen contaminated with blood, urine and feces, respectively, were lower (P <0.05) than the control whose average was 91.5%. Treatment contaminated with urine was lower (P <0.05) than the control treatment for DNA integrity (82.8 and 93.4%, respectively) and mitochondria functionality (87.1% and 94.9%, respectively). Therefore, most parameters of semen quality were impaired by the inclusion of contaminants tested (feces, urine or blood) at a concentration of 10%.
17

A critical evaluation of the causes of carcass condemnations in a South African cattle abattoir

Tlhapi, Petrus Thabo January 2013 (has links)
This study was conducted to investigate the causes and the effects of breed, gender and season on carcass condemnations post-mortem in a large South African abattoir. Condemnation of carcasses as a results of animal diseases and conditions has been identified as a problem in the South African beef industry, but the causes and extent of carcass condemnations have not been studied in detail. The importance of cattle management during transportation and pre-slaughter is generally appreciated, but a better understanding of the influence of breed, gender and season on the prevalence of carcass condemnations can help to improve slaughter management at large abattoirs. Diseases and conditions evaluated during this study were parafilaria, bruising, soiling, fever, peritonitis and pleuritis, abscesses, measles, oedema and intramuscular haemorrhage. Breeds of cattle slaughtered were Friesland, Bonsmara, Brahman, Angus, Afrikander, Hereford and Nguni cattle, grouped as males and females, and the seasonal effects investigated were confined to Autumn, Winter and Summer combined with Spring as it was not easy to distiquish between the two. Data was collected in a Grade A abattoir in South Africa in 2010. The experimental design involved 42 combinations based on their effects and interactions namely 7 breeds x 2 genders x 3 seasons. The model used in this procedure was based on the presence of conditions = (Intercept) x i x j x k where i~breed, j~gender and k~season. The binary response variable was the presence (value = 1) or absence (value = 2) of the respective condition. Overall, the significant order and extent of causes of bovine carcass condemnations evaluated in this particular abattoir during the period of study were peritonitis and pleuritis at 2.49%, soiling 2.33%, bruising 2.10%, parafilaria 0.54%, while other conditions had a negligible effect. Almost half of these carcass condemnations were due to soiling and bruising, which can be addressed by implementing better abattoir management and better management during transportation. Peritonitis and pleuritis were prevalent to a greater degree in Autumn, Soiling in Summer, bruising in winter and parafilaria more prevalent in Summer as well. Bonsmara bulls were more affected by peritonitis and pleuritis, soiling, bruising and parafilari compared to other breeds.. Overall breed, gender and season influenced carcass condemnations in large South African abattoir It is suggested that proper dehorning should be done at an early stage, especially in bulls of breeds like Bonsmara, Nguni, Friesland and Hereford, which predispose cattle to bruising which increases the number of carcass condemnations. Steps should be taken (i.e. proper handling techniques should be applied) to avoid injuries which may lead to internal bleeding, and eventually bruises (most probably due to fighting during transportation or in lairage), that can be avoided by using improved and upgraded facilities which include enough space per animal. In case of soiling, well-trained slaughter personnel, cattle handlers and cleaners should be hired to prevent bile and soil contamination during evisceration and to avoid mud or manure contamination durinmg lairage. It is recommended that employees be trained to help reduce the high rate of carcass condemnations. Breeds like Bonsmara and Brahman were more susceptible to peritonitis, pleuritis and parafilaria, so treatrment programmes are advisable for these breeds, especially those from regions where these conditions or diseases are more prevalent. / Dissertation (MSc Agric)--University of Pretoria, 2013. / gm2014 / Animal and Wildlife Sciences / unrestricted
18

Feedlot performance of the Drakensberger in comparison with other cattle breeds : a meta-analysis

Niemand, Mia 23 May 2013 (has links)
The aim of this study was to compare the growth performance and incidences of health disorders of the Drakensberger breed to the collective total of all other beef breeds in feedlots. The objective was to conduct a meta-analysis on the performance, health and centralised growth data (Phase C) of all cattle breeds from different regions in South Africa. The intention was not to compare different breeds with each other but only the Drakensberger breed to other breeds and crossbreeds generally found in feedlots. Results from Phase C performance tests at the centres, as well as historical growth and health data were gathered from a number of feedlots. Data from feedlots were only accepted when individual animal records were kept; classification was according to breed type; and when Drakensbergers were present in the particular feedlot. The aim was to utilise historical records of up to ten years per feedlot. After initial processing and elimination of outliers, a meta-analysis was performed on the growth data. Each feedlot was analysed separately, followed by a final meta-analysis, which incorporated results from all the feedlots. It included 497 798 head of cattle from 5 feedlots, with a separate analysis on Phase C performance test data, comprising of 6139 animals from 4 Agricultural Research Council (ARC) test centres. Health data from 2 feedlots, comprising of 24 819 animals, along with Phase C performance test data from 2 ARC test centres, including 1746 head of cattle, were analysed. The variables included in the analysis were: average daily gain (ADG), feed conversion ratio (FCR), mortality and morbidity ratios and type of disease or disorder. In addition to determining the individual effects of breed, sex, season, year, region and diseases, possible interactions amongst these factors were investigated. The meta-analysis on the feedlot performance and Phase C performance tests revealed that other breeds had a higher (P < 0.01) ADG than Drakensbergers. No difference was observed between Drakensbergers and other breeds within gender and within season. The meta-analysis on Phase C performance test data showed no significant difference in FCR between Drakensbergers and other breeds. A feedlot study, including 23 554 head of cattle, has shown that Drakensbergers have a higher rate (P < 0.01) of respiratory disease occurrence during the winter season than other breeds. Likewise, results from the ARC test centre in Irene, consisting of 1553 animals, reveal that the occurrence of respiratory diseases was less (P < 0.01) in other breeds than in Drakensbergers. However, there seem to be no significant differences in the occurrence of metabolic disturbances and other diseases between Drakensbergers and other breeds. Although a statistical difference of only 20 grams per day (P < 0.01) in ADG were found between Drakensbergers and other breeds in feedlots and test centres, the biological and economical effect would most probably be insignificant. The large dataset of close to 500 000 cattle also contributed to such a small weight difference being significant. The majority of the contributing feedlots stated that their record keeping lack accuracy and do not comprise of a complete set of health data. Readers are therefore advised to interpret the health data analyses with caution as the analyses are not representative of the actual health status of cattle in the feedlot industry, simply because accurate data does not exist. / Dissertation (MSc(Agric))--University of Pretoria, 2013. / Animal and Wildlife Sciences / unrestricted
19

Verifying parentage and gender of domestic dog conceptuses using microsatellites

Steckler, Daniela 21 December 2010 (has links)
Parentage testing in the domestic dog is finding increasing application for dog breed registries as well as in research. The aim of parentage verification is the correct assignment of both parents to the offspring. For accurate parentage verification informative microsatellite markers have to be identified. More powerful models to study artificial insemination in bitches will be possible if the paternity and gender of early dog conceptuses can be determined. The amelogenin gene locus has been used in bovine day six to day seven embryos for early gender determination but no research has been done on early conceptuses of the domestic dog. The aim of the current study was to establish an accurate method for parentage and gender determination from domestic dog conceptuses during early pregnancy in a multi-sire insemination trial. Semen from 10 male dogs was used in each of 12 females for artificial insemination. Blood and uterine tissue for DNA extraction was collected from males and females, and embryonic material was collected after ovariohysterectomy between 16 and 30 days after the onset of cytological dioestrus. Twenty-three microsatellite markers were used for parentage verification, and the amelogenin gene locus for gender determination. Mean observed heterozygosity, mean expected heterozygosity (HExp), and mean PIC were high (0.6753, 0.6785, and 0.628, respectively). There were 66 conceptuses. In two, neither parentage nor gender could be established because their tissue samples were contaminated. Parentage could be assigned by CERVUS 3.0.3 in 42 out of 64 of the cases (66%) without difficulty. Another 33% of the cases (21 out of 64) could be resolved using the number of exclusions, LOD scores or manual verification of genotyping errors. In one conceptus, paternity could not be established because its sire may have been either of two siblings. The gender of the female and male dogs was successfully confirmed using the amelogenin gene locus. The gender of the conceptuses was determined using the amelogenin gene locus (50% male, 50% female) but not confirmed by another method of gender determination such as karyotyping. As shown in the current study, the panel of 24 microsatellite markers used provides high information content suitable for parentage verification in multi-sire litters, as well as gender determination of early conceptuses. / Dissertation (MSc)--University of Pretoria, 2010. / Production Animal Studies / unrestricted
20

A Comparison of the Effects of Heat Stress on Milk and Component Yields and Somatic Cell Count in Holstein and Jersey Cows

Smith, Daniel L 09 December 2011 (has links)
Objective 1 was to investigate effects of heat stress and breed on milk and component yield for Holstein and Jersey cows on the same farm. Objective 2 was to determine the effects of breed on udder health as measured by somatic cell count (SCC) during times of heat stress. Data were collected from DHIA records of 142 Jersey cows and 586 Holstein cows from the University herd at Mississippi State University. During heat stress Jersey milk yield and 4% fat corrected milk (FCM) increased (P<0.01). Holstein milk yield and FCM decreased during heat stress (P<0.01). Heat stress affected somatic cell count (SCC) although effects varied by intensity of heat stress. Breed did not have an affect on SCC. Milk fat and protein percentages declined for both breeds in heat stress conditions. Milk fat but not milk protein of Jersey cows increased as stress increased from mild to severe.

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