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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

Morphology of peri-partal placentomes and post-partal foetal membranes in African buffalo (Syncerus caffer) and comparative aspects with cattle (Bos taurus)

Schmidt, Susanne. January 2005 (has links)
Thesis (MSc (Veterinary Science))--University of Pretoria, 2005. / Includes bibliographical references.
12

Die invloed van selenium en β-karoteentoediening op geselekteerde plasmaparameters en die dragtigheidsyfer van ontvangerkoeie tydens embrio-oorplasing / The influence of selenium and β-carotene administration on selected plasma parameters and pregnancy rates of recipient cows during embryo transfer

Bruwer, Floris Johannes 16 November 2006 (has links)
Hierdie studie het ten doel gehad om die effekte van Se en β-karoteentoediening op vit A, vit E, konsepsietempo en progesteroonvlakke tydens embrio-oorplasings in ontvangerkoeie te ondersoek. Die effekte van die verskillende faktore op mekaar sou ook bepaal word. In Totaal van 142 multipare koeie wat in vier groepe verdeel is, was as ontvangers vir die studie gebruik. Die groepe was as volg behandel: Groep 1 (35 koeie), 50 mg Se en 1500 mg vit E intramuskulêr 6 en 3 weke voor die oorplasings; Groep 2 (36 koeie), 300 mg l1-karoteen per os per bees per dag vanaf 6 weke voor die oorlasings; Groep 3 (36 koeie), vit E/Se en β-karoteen soos in Groepe 1 en 2 respektiewelik; Groep 4 (35 koeie) negatiewe kontrole groep met geen behandeling nie. Elke ontvanger het 6 weke voor oorplasing vit ADE oraal ontvang. Embrios is na 20, 19, 19 en 18 ontvangers van Groepe 1, 2, 3 en 4 onderskeidelik oorgeplaas. Bloedmonsters is van elke dier vir ontledings in die middel van die oorplantingsperiode getrek. Die toediening van Se was hoogs betekenisvol met RBS GSH-Px aktiwiteit gekorreleer R2 = 0,32960, (n = 136, P = 0,0000). Die toediening van β-karoteen was ook hoogs betekenisvol gekorreleer met die RBS GSH-Px aktiwiteit, R2 = 0,18950, (n=136, P< 0,0000). Die RBS GSH-Px aktiwiteit was 7,49,6,61,10,75 en 4,5 EE 11x1010 RBS vir Groepe 1, 2, 3 en 4 onderskeidelik. Groepe 1 en 3,1 en 4, 2 en 3, 2 en 4, en 3 en 4 het betekenisvol van mekaar verskil maar nie Groepe 1 en 2 nie. Daar was geen verband tussen β-karoteen plasmavlakke en RBS GSH¬Px aktiwiteit nie. Die orale toediening van β-karoteen het plasmavlakke duidelik laat styg en was betekenisvol met die β-karoteen plasmavlakke gekorreleer R2 = 0,09296, (n = 134, P=O,0003). Die groepe wat β-karoteen ontvang het, Groepe 2 en 3, se plasmavlakke was merkbaar hoër as die van Groepe 1 en 4 wat niks ontvang het nie. Die groep se waardes was 8,72, 10,13, 9,53 en 8,50 µmol/l vir Groepe 1, 2, 3 en 4 respektiewelik. Groepe 1 en 2, 2 en 4, en 3 en 4 het betekenisvol van mekaar verskil (P=0,0021) maar nie Groepe 1 en 3, en 1 en 4 nie. Daar was 'n positiewe korrelasie tussen die toediening van vit E/Se en die a¬tocoferol plasmavlakke, R2 = 0,06344, (n = 134, P=0,0033). Daar was egter geen aanduiding van 'n verband tussen RBS GSH-Px aktiwiteit en α-tocoferol plasmavlakke nie. Daar was wel In betekenisvolle korrelasie tussen α-tocoferol en β-karoteen plasmavlakke (P=0,0001). Die groepswaardes was 11,90, 10,59, 11,67 en 10,56 vir Groepe 1, 2, 3 en 4 onderskeidelik. Groepe 1 en 2, en 1 en 4 het betekenisvol van mekaar verskil (P=0,0334) maar nie die ander groepe, Groepe 1 en 3, 2 en 3, 2 en 4, en 3 en 4 nie. Die korrelasie tussen die toediening van Se en die retinol plasmavlakke was nie statisties betekenisvol nie (P=0,0671) maar tussen RBS GSH-Px aktiwiteit en retinol plasmavlakke was dit wel betekenisvol R2 = 0,03086, (n = 133, P=0,0431). Daar was ook In waarskynlike korrelasie tussen die toediening van β-karoteen en die retinol plasmavlak (P=0,0835) maar geen korrelasie tussen β-karoteen plasmavlakke en retinol plasmavlakke nie. Die groepwaardes was 1,068, 1,065, 1,154 en 1,026 µmol/l vir Groepe 1, 2, 3 en 4 onderskeidelik. Die dragtigheidstempo na die oorplasing van embrios was 50,0%, 47,4%, 31,5% en 27,8% vir Groepe 1, 2, 3 en 4 onderskeidelik. Die verskille was nie betekenisvol nie. Daar was 'n negatiewe korrelasie tussen die β-karoteen plasmavlakke en progesteroon plasmavlakke vir die eerste 5-9 dae van die estrussiklus. Retinol plasmavlakke en progesteroon plasmavlakke was wel positief gekorreleer (P=O,0317). Die groepswaardes was 5,67, 2,90, 4,28 en 5,60 µmol/l vir Groepe 1, 2, 3 en 4 onderskeidelik. RBS GSH-Px was betekenisvol gekorreleer met corpus luteum grootte maar corpus luteum grootte was nie met progesteroon waardes gekorreleer nie. Daar was geen statistiese verskille tussen die groepe ten opsigte van estruslengte en die tydsduur tussen prostaglandientoediening en estrus nie. Op individuele basis was daar wel In betekenisvolle korrelasie van β-karoteen plasmavlak met beide estruslengte (P=O,0298) en die tydsduur tussen prostaglandientoediening en estrus (P=0,0130). Estruslengte en die tydsduur tussen prostaglandien en estrus was ook betekenisvol met mekaar gekorreleer (P < 0,0000). / This study addressed some of the effects that selenium and β-carotene administration have on vit A, vit E, conception rates, progesterone levels, oestrus length, interval from PG to oestrus and corpus luteum size in embryo recipients. A total of 142 multiparous cows asigned to 4 test groups, were used as recipients in this study. Group 1 (35 cows) received 50 mg Se and 1500 mg vit E intramuscularly 6 and 3 weeks before transfer, Group 2 (36 cows) received 300 mg β-carotene orally per cow per day starting 6 weeks prior to transfer, Group 3 (36 cows) received both vit ElSe and β-carotene as per Group 1 and 2 and Group 4 (35 cows) was a negative control, with no treatment. All recipients received vit ADE orally 6 weeks before transfers. Embryos were transferred to 20, 19, 19, and 18 recipients of the Groups 1, 2, 3 and 4 respectively. Blood for analysis was drawn from all the recipients in the middle of the transferal week, being day 3 of the 5-day period. The administration of selenium was highly significantly correlated with the corresponding RBS GSH-Px activity R2 = 0,3290, (n = 135, P < 0,0000). The β-¬carotene administration was also highly significantly correlated with the RBS GSH¬Px activities R2 = 0,18950, (n = 136, P < 0,0000). However, there were no correlation between the β-carotene plasma levels and that of the RBS GSH-Px activities. The RBS GSH-Px were 7,49, 6,61, 10,75 and 4,5 Enzyme Units 11x1010 RBS for Groups 1, 2, 3 and 4 respectively. Groups 1 and 3, 1 and 4, 2 and 3, 2 and 4, and 3 and 4 differ significantly from each other but not Groups 1 and 2. There were no connection between B-carotene plasma levels and RBS GSH-Px activities. The treatment of β-carotene itself was succesful and was significantly correlated with the resulting β-carotene plasma levels R2 = 0,09296, (n = 134, P = 0,0033). The β-carotene plasma levels of the groups that received β-carotene, Groups 2 and 3, were noticeably higher than those of Group 1 and 4, which did not receive β-carotene. The values were 8,72, 10,13, 9,53 and 8,5 µmol/l for Groups 1, 2, 3 and 4 respectively. Groups 1 and 2, 2 and 4, and 3 and 4 differed significantly from one another (P = 0,0021) but not those of Groups 1 and 3, and 1 and 4. There was a positive correlation between the administration of Se and the retinol plasma levels (P = 0,0671) and a positive significant correlation between the RBS GSH-Px and the retinol plasma levels R2 = 0,03086, (n = 133, P = 0,0431). There was also a positive correlation between the administration of β-carotene and the retinol plasma levels (P = 0,0835) but no correlation between β-carotene plasma levels and retinol plasma levels. The values were 1,068, 1,065, 1,154 and 1,026 µmol/ for Groups 1, 2, 3 and 4 respectively. The pregnancy rate after embryo transferal were 50%, 47,4%, 31,5% and 27,8% for Groups 1, 2, 3 and 4 respectively. The differences were not significant. There was a negative correlation between β-carotene plasma levels and progesterone plasma levels for the first 5 to 9 days of the oestrus cycle. Retinol plasma levels however were significantly correlated with progesterone plasma levels (P = 0,0317). The progesterone levels were 5,67, 2,90, 4,28 and 5,60 µmol/ for Groups 1, 2, 3 and 4 respectively. The RBS GSH-Px activity was significantly correlated with corpus luteum size (P = 0,0445) but corpus size was not correlated with progesterone values. There were no statistical differences amongst the groups, between oestrus length and the interval from prostaglandin to oestrus. However on an individual basis there was a significant correlation between β-carotene plasma levels and both the oestrus length (P = 0,0298) and the interval from prostaglandin to oestrus (P = 0,0130). Oestrus length and the interval from prostaglandin to oestrus were also significantly correlated with each other (P < 0,0000). / Dissertation (MMedVet)--University of Pretoria, 2000. / Production Animal Studies / MMedVet / Unrestricted
13

The in vitro produced cow embryo : factors affecting development and metabolism

Steeves, Tracey Elizabeth, 1968- January 2000 (has links)
Abstract not available
14

Effect of immunoglobulins on early bovine embryo development in vitro

Sedano, Rodolfo Canseco 12 March 2013 (has links)
Bovine morulae (day 6: n=257) were obtained to evaluate the [effect of immunoglobulins (Ig) on early bovine embryo development in vitro. Fifty-four cows superovulations were conducted in 36 cows with follicle stimulating hormone. Embryos were collected by non-surgical procedures and morphologically evaluated and randomly assigned to culture. Embryos were cultured in Ham's F-10 containing 10% (6.4 mg/ml) steer serum (SS), 1% (.64 mg/ml) bovine gamma . globulins (GG), 1% (.64 mg/ml) bovine IgG, 1% (.64 mg/ml) bovine 1gM, 10% SS plus 1% GG, 10% SS plus 1% 1gG, or 10% SS plus 1% 1gM. Embryos were cultured to the hatched blastocyst stage or degeneration and evaluated at 12 h intervals. / Master of Science
15

Etude de la dysmorphose craniofaciale chez le rat Dumbo

Katerji, Suhair 22 June 2009 (has links)
Le rat Dumbo présente un aspect malformatif évoquant certains syndromes crânio-faciaux humains. La compréhension du phénotype Dumbo pourrait expliquer les événements cellulaires et moléculaires à l’origine de ces syndromes. Le données recueillies chez le rat Dumbo et comparées à celles du rat Wistar sont susceptibles de constituer de précieuses informations éventuellement transposables à l’espèce humaine.<p><p>La première étape de cette étude a consisté en des analyses morphologiques et morphométriques afin de vérifier les perturbations morphologiques communes entre les rats Dumbo et les syndromes malformatifs humains :la brièveté des os zygomatique, maxillaire, mandibulaire et la position basse des oreilles. Ces analyses ont été réalisées sur les squelettes embryonnaires âgés de 16 jours à 21 jours de rats Dumbo et Wistar à l’aide d’une coloration in toto au Bleu Alcian – Alizarine. La deuxième étape de cette étude consistait en une analyse cytogénétique. Pour ce faire, nous avons établi le caryotype du rat Dumbo et nous l’avons comparé avec le caryotype du rat Wistar. L’étape suivante fut de procéder à l’analyse histologique des malformations crânio-faciales chez le rat Dumbo en observant la chondrogenèse pendant la morphogenèse crânio-faciale. Enfin, l’examen de l’expression des gènes Msx1 sens (S) ,Msx1 antisens (AS) et Dlx1 dans l’extrémité céphalique des rats Dumbo a été réalisé par les techniques de RT–PCR (Reverse Transcription Polymerase Chain Reaction method). Des estimations semi-quantitatives ont été validées en utilisant des dilutions ADNc du rat Wistar. Des densitométries de la densité d’amplicons fluorescence ont été réalisées à l’aide du logiciel VilberLourmat Bio1D software.<p><p>Les résultats obtenus ont permis de caractériser de manière précise les malformations crânio-faciales chez le rat Dumbo.<p> <p>1-\ / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

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