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Relations entre le statut utérin, les paramètres biochimiques du sérum et du liquide de lavage utérin et la production d’embryons chez les vaches laitières après surovulationRasolomboahanginjatovo, Hasina Santatriniaina 03 1900 (has links)
Le développement et la survie de l’embryon dépendent des nutriments fournis par les sécrétions utérines. Les objectifs de cette étude étaient de déterminer l’effet de la surovulation (SOV) sur la bactériologie et cytologie utérine et sur les paramètres biochimiques utérin et sérique et leurs effets sur le nombre d’embryons transférables (ET). Deux groupes de vaches Holstein (groupe I, non lactante, n=7 et groupe II, lactante, n=28) ont été respectivement induites en chaleur ou surovulées et ensuite inséminées. Au jour 7 du cycle œstral (J7) et lors du jour de la récolte (JR), un prélèvement individuel de sang et de liquide de lavage utérin a été fait pour l’analyse du statut bactériologique et cytologique de l’utérus et la mesure de la concentration de plusieurs paramètres biochimiques présélectionnés. Les embryons récoltés ont été évalués selon les critères de l’IETS. La SOV a donnée une moyenne de 7.39 ± 6.22 ovocytes/embryons dont 3.32 ± 4.81 ET. Il n’y avait pas de variation significative de la bactériologie et cytologie utérine des deux groupes entre J7 et JR. La concentration sérique de l’urée (P=0.0001), d’E2 (P=0.006); la concentration utérine du Glu (P=0.002), de Ck (p=0.0007), de LDH (P <0.0001), de PT (P=0.004), de P4 (P=0.008), de PGFM (P<0.0001) du groupe I et la concentration sérique de P4 (P<0.0001), de PGFM (P<0.0001); la concentration utérine de LDH (P=0.002), de PGFM (P<0.0001) du groupe II ont été significativement élevées à JR qu’à J7. La concentration utérine et sérique de l’urée (P<0.0001 et P<0.0001), de LDH (P<0.0001 et P=0.008), la concentration sérique de P4 (P=0.0002) et la concentration utérine de PT (P=0.0003) à JR du groupe II étaient différente du groupe I. Il n’y avait pas d’association entre la bactériologie et cytologie utérine et le nombre d’ET. Cependant, le nombre d’ET a été positivement corrélé avec la concentration sérique d’IGF-1 à J7 (r=0.45; P=0.001) et la concentration sérique de P4 à JR (r=0.43; P<0.05) et négativement corrélé avec la concentration utérine et sérique de PGFM à la fois à J7 (r=-0.54; P<0.005 et r=-0.67; P<0.001) et à JR (r=-0.48; P<0.01 et r=-0.57; P<0.002). Ces résultats suggèrent que la SOV induit des changements au niveau sérique et utérin qui affectent le nombre d’ET récoltés. / The developing embryo is dependent on the nutrients provided by the oviduct and the uterine fluid. The objectives of this study were to determine the effect of SOV on uterine bacteriology and cytology, on serum and uterine biochemical parameters and consequently on the number of TE. Non-lactating (n=7) and lactating (n=28) Holstein cows were synchronized for estrus and superovulated respectively and were inseminated twice. Uterine bacteriology and cytology and various uterine and serum biochemical parameters were measured at day 7 of estrus cycle (D7, starting day of the SOV protocol) and at the designated day of embryo recovery (DER). Harvested embryos were evaluated according to IETS’s criteria. Superovulated cows produced an average of 7.39 ± 6.22 ova/embryos of which 3.32 ± 4.81 were TE. There were no significant variations of uterine bacteriology and cytology between D7 and DER within the two groups. Serum urea (P=0.0001), E2 (P=0.006); uterine Glu (P=0.002), Ck (P=0.0007), LDH (P<0.0001), TP (P=0.004), P4 (P=0.008), PGFM (P<0.0001) in group I and serum P4 (P<0.0001), PGFM (P<0.0001); uterine LDH (P=0.002), PGFM (P<0.0001) in group II were significantly higher at DER than at D7. At DER, group I was different to group II’ uterine and serum urea (P<0.0001 and P<0.0001), LDH (P<0.0001 and P=0.008), PGFM (P=0.002 and P=0.009), serum P4 (P=0.0002) and uterine TP (P=0.0003). There was no association between uterine bacteriology and cytology and the number of TE. However, TE was positively correlated with serum IGF-1 at D7 (r=0.45; P=0.001) and P4 at DER (r=0.43; P<0.05) and negatively correlated with both serum and uterine PGFM respectively at D7 (r=-0.54; P<0.005 and r=-0.67; P<0.001) and DER (r=-0.48; P<0.01 and r=-0.57; P<0.002). The present results infer that changes following SOV in both serum and uterine secretion may affect the number of TE.
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Echecs précoces de gestation chez la vache laitière de race Holstein : incidences, implication dans la baisse de fertilité et facteurs de risque / Early pregnancy failures in Holstein dairy cows : Incidence, Role in the decrease fertility, risk factorsLedoux, Dorothée 08 July 2011 (has links)
Actuellement en France et aux Etats-Unis, seules 30 à 35 % des premières inséminations artificielles chez la vache Holstein aboutissent à un vêlage. Les échecs de gestation ont lieu le plus souvent au cours du développement embryonnaire (Non-Fécondation-Mortalité Embryonnaire Précoce (NF-MEP) entre 0 et 16 jours, Mortalité Embryonnaire Tardive (MET) entre 16 et 45 jours après insémination). Ces échecs précoces de gestation expliquent en grande partie les différences de fertilité observées en France entre la race Holstein et les autres races plus fertiles. Les facteurs de risque de l'interruption de la gestation sont multiples : liés à l'animal, à l'environnement et à la conduite de l'élevage. Trois facteurs cependant ont évolué au cours du temps pour les vaches Holstein : le potentiel génétique, les anomalies de reprise de la cyclicité après vêlage, le déficit énergétique en début de lactation. Notre objectif a été d'identifier l'influence de ces trois facteurs sur les échecs précoces de gestation après première insémination postpartum chez la vache de race Holstein. Le potentiel génétique a été associé à l'incidence de NF-MEP et de MET. Les phases lutéales prolongées sembleraient être à l'origine d'une augmentation d'incidence de MET. Le déficit énergétique a eu un effet sur la NF-MEP et sur la MET. L'effet du déficit énergétique postpartum sur la qualité des ovocytes au moment de la mise à la reproduction reste hypothétique. Notre travail sur les échecs précoces de gestation a permis de contribuer à fournir des outils d'amélioration de conduite d'élevage aux professionnels. / Currently, in France and the United States of America, only 30-35 % of first artificial inseminations in Holstein cows result in a calving. Pregnancy failure mainly occurs during embryonic development (fertilization failure - early embryonic mortality (FF-EEM) between D0 and D16 or late embryonic mortality (LEM) between D16 and D45 after insemination). Early pregnancy failure explains the majority of the differences in fertility between the Holstein breed and the other breeds in France, which are more fertile. There are numerous risk factors which cause pregnancy failure: animal, environmental and farm management factors. There are however, three factors which have been modified over time in Holstein cows: genetic merit, abnormal patterns of resumption of cyclicity and negative postpartum energy balance (NEB). Our objective was to identify the relationships between these three factors and early pregnancy failure after first postpartum insemination in Holstein dairy cows. Genetic merit was related to the incidence of FF-EEM and LEM. Prolonged luteal phases seemed to increase the incidence of LEM. The NEB was associated with FF-EEM and LEM. The impact of NEB on oocyte quality during the breeding period remains unclear. Our early pregnancy failure studies have helped to provide some tools to improve farm management.
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Relations entre le statut utérin, les paramètres biochimiques du sérum et du liquide de lavage utérin et la production d’embryons chez les vaches laitières après surovulationRasolomboahanginjatovo, Hasina Santatriniaina 03 1900 (has links)
Le développement et la survie de l’embryon dépendent des nutriments fournis par les sécrétions utérines. Les objectifs de cette étude étaient de déterminer l’effet de la surovulation (SOV) sur la bactériologie et cytologie utérine et sur les paramètres biochimiques utérin et sérique et leurs effets sur le nombre d’embryons transférables (ET). Deux groupes de vaches Holstein (groupe I, non lactante, n=7 et groupe II, lactante, n=28) ont été respectivement induites en chaleur ou surovulées et ensuite inséminées. Au jour 7 du cycle œstral (J7) et lors du jour de la récolte (JR), un prélèvement individuel de sang et de liquide de lavage utérin a été fait pour l’analyse du statut bactériologique et cytologique de l’utérus et la mesure de la concentration de plusieurs paramètres biochimiques présélectionnés. Les embryons récoltés ont été évalués selon les critères de l’IETS. La SOV a donnée une moyenne de 7.39 ± 6.22 ovocytes/embryons dont 3.32 ± 4.81 ET. Il n’y avait pas de variation significative de la bactériologie et cytologie utérine des deux groupes entre J7 et JR. La concentration sérique de l’urée (P=0.0001), d’E2 (P=0.006); la concentration utérine du Glu (P=0.002), de Ck (p=0.0007), de LDH (P <0.0001), de PT (P=0.004), de P4 (P=0.008), de PGFM (P<0.0001) du groupe I et la concentration sérique de P4 (P<0.0001), de PGFM (P<0.0001); la concentration utérine de LDH (P=0.002), de PGFM (P<0.0001) du groupe II ont été significativement élevées à JR qu’à J7. La concentration utérine et sérique de l’urée (P<0.0001 et P<0.0001), de LDH (P<0.0001 et P=0.008), la concentration sérique de P4 (P=0.0002) et la concentration utérine de PT (P=0.0003) à JR du groupe II étaient différente du groupe I. Il n’y avait pas d’association entre la bactériologie et cytologie utérine et le nombre d’ET. Cependant, le nombre d’ET a été positivement corrélé avec la concentration sérique d’IGF-1 à J7 (r=0.45; P=0.001) et la concentration sérique de P4 à JR (r=0.43; P<0.05) et négativement corrélé avec la concentration utérine et sérique de PGFM à la fois à J7 (r=-0.54; P<0.005 et r=-0.67; P<0.001) et à JR (r=-0.48; P<0.01 et r=-0.57; P<0.002). Ces résultats suggèrent que la SOV induit des changements au niveau sérique et utérin qui affectent le nombre d’ET récoltés. / The developing embryo is dependent on the nutrients provided by the oviduct and the uterine fluid. The objectives of this study were to determine the effect of SOV on uterine bacteriology and cytology, on serum and uterine biochemical parameters and consequently on the number of TE. Non-lactating (n=7) and lactating (n=28) Holstein cows were synchronized for estrus and superovulated respectively and were inseminated twice. Uterine bacteriology and cytology and various uterine and serum biochemical parameters were measured at day 7 of estrus cycle (D7, starting day of the SOV protocol) and at the designated day of embryo recovery (DER). Harvested embryos were evaluated according to IETS’s criteria. Superovulated cows produced an average of 7.39 ± 6.22 ova/embryos of which 3.32 ± 4.81 were TE. There were no significant variations of uterine bacteriology and cytology between D7 and DER within the two groups. Serum urea (P=0.0001), E2 (P=0.006); uterine Glu (P=0.002), Ck (P=0.0007), LDH (P<0.0001), TP (P=0.004), P4 (P=0.008), PGFM (P<0.0001) in group I and serum P4 (P<0.0001), PGFM (P<0.0001); uterine LDH (P=0.002), PGFM (P<0.0001) in group II were significantly higher at DER than at D7. At DER, group I was different to group II’ uterine and serum urea (P<0.0001 and P<0.0001), LDH (P<0.0001 and P=0.008), PGFM (P=0.002 and P=0.009), serum P4 (P=0.0002) and uterine TP (P=0.0003). There was no association between uterine bacteriology and cytology and the number of TE. However, TE was positively correlated with serum IGF-1 at D7 (r=0.45; P=0.001) and P4 at DER (r=0.43; P<0.05) and negatively correlated with both serum and uterine PGFM respectively at D7 (r=-0.54; P<0.005 and r=-0.67; P<0.001) and DER (r=-0.48; P<0.01 and r=-0.57; P<0.002). The present results infer that changes following SOV in both serum and uterine secretion may affect the number of TE.
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Etude de la fertilité et du métabolisme des vaches laitières sélectionnées pour l'haplotype "fertil+" ou "fertil-" à un QTL de fertilité situé sur le chromosome 3 / Fertility and metabolism of dairy cows carrying "Fertil+" or "Fertil-" haplotype for a fertility QTL located on the chromosome 3Coyral-Castel, Stéphanie 06 July 2012 (has links)
Au cours des dernières décennies, une dégradation de la fertilité des vaches laitières, parallèlement à une augmentation de la production laitière a été observée. Des régions du génome, les QTL, affectent la fertilité femelle. Le but de ce travail de thèse est d’étudier la fertilité et certains paramètres zootechniques chez des vaches Prim'Hosltein en première lactation choisies pour leur haplotype favorable "fertil+" ou défavorable "fertil-" pour un QTL de fertilité situé sur le chromosome 3. Ce phénotypage a montré une meilleure fertilité et un meilleur bilan énergétique dans la première semaine de lactation pour les vaches "fertil+" par rapport aux vaches "fertil-". De plus, les vaches "fertil-" ont un flux d’ingestion plus rapide. Au pic de mobilisation, certains gènes du QTL étaient différentiellement exprimés dans le tissu adipeux des deux haplotypes. Dans les cellules de la granulosa, un de ces gènes, nommé Kirrel, est plus exprimé chez les vaches "fertil+" et sa protéine recombinante inhibe la sécrétion de progestérone in vitro. Notre travail a permis d'affiner les interactions génotype-phénotype liées à un QTL de fertilité et de mettre en avant un des possibles rôles d'un gène de ce QTL dans la fonction de reproduction chez la vache laitière. / In recent decades, the dairy cow fertility has declined, in parallel with an increase in milk production. Some regions of the genome, named QTL, affect female fertility. The purpose of this thesis is to study fertility and some zootechnical parameters in Prim'Hosltein cows in first lactation chosen for their favorable haplotype "fertil+" or unfavorable haplotype "fertil-" for one fertility QTL on chromosome 3. This phenotyping showed better fertility and energy balance in the first week of lactation for "fertil+" than for "fertil-" cows. In addition, "fertil-" cows had a higher eating rate. At the peak of mobilization, the QTL genes are differentially expressed in adipose tissue of "fertil+" and "fertil-" cows. In granulosa cells, one of these genes, named Kirrel, is higher expressed in "fertil+" cows and its recombinant protein inhibits the secretion of progesterone in vitro. Our work has contributed to refine interactions genotype-phenotype linked to one fertility QTL and highlighted one of the possible roles of a gene which belongs to this QTL in the reproductive function in dairy cows.
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Merkmalsbezogene Einstellungen von Lehrkräften zur schulischen Inklusion in Sachsen - eine empirische AnalyseWinkler, Cornelia 15 June 2016 (has links) (PDF)
In Bezug zu den Forderungen der UN-BRK nach einer inklusiven Schule wurden in dieser Studie inklusive Einstellungen, Unterrichtspraktiken und Ressourcen integrativ arbeitender Lehrkräfte in Sachsen und Schleswig-Holstein identifiziert. Mithilfe eines Fragebogens erfolgte eine quantitative Querschnittsstudie mit einer Stichprobe von 363 Lehrkräften. In Anlehnung an den „Index für Inklusion“ wurden dabei Indikatoren zu integrativen bzw. inklusiven Menschenbildern, Schulkultur und Schulorganisation, pädagogischen Unterrichtspraktiken sowie Fortbildungen und Ressourcen abgeleitet. Den Items liegt eine vierstufige Likert-Skala zugrunde. Im Rahmen der Auswertung wurden relevante Indikatoren identifiziert und schulartbezogen sowie länderbezogen verglichen (einfaktorielle Anova). Offene Fragen wurden kategorisiert und ausgewertet. Im Ergebnis werden die Befürwortung von Heterogenität und Individualisierung, passende Rahmenbedingungen für den inklusiven Kontext und der Entwicklungsvorsprung aufgrund längerer Traditionen der sächsischen Grundschulen und der Integration in Schleswig-Holstein deutlich.
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Estimation of genetic parameters for fertility traits and the effect of milk production on reproduction performance in South African Holstein cowsPotgieter, Johannes Phillipus 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Profitable milk production and genetic improvement in dairy herds are largely dependant on fertile
cows capable of calving down on an annual basis. Several studies indicate declines in the
reproductive performance of Holstein cows over the last 30 years. Calving interval (CI) and services
per conception (SPC) are being used by dairy farmers as indicators of the reproductive performance
of dairy cows. However, using these traits as cow fertility indicators is problematic as CI is dependent
on subsequent calving dates while SPC is strongly linked to inseminator proficiency. The aim of the
study is therefore, firstly, to describe alternative fertility traits derived from insemination and calving
dates and pregnancy check results. The effects of some non-genetic factors on these traits are
discussed. Means±sd for interval traits from calving to first insemination (CFS) and the interval from
calving to conception (DO) were respectively 77±30 and 134±74 days while the number of services
per conception (SPC) averaged 2.55±1.79. The percentage of first servics occurring within 80 days
post-partum (FS80d) and the proportion of cows being confirmed pregnant within 100 (PD100d) and
200 days post-partum (PD200d) were 0.64±0.48, 0.36±0.48 and 0.71±0.45, respectively. Although
fertility traits were affected significantly by lactation number, calving year and month, herds
(managers) had the largest effect.
Fertility is a complex trait, however, the challenge is finding traits that best describe this trait. Genetic
parameters for these traits could give an indication of the response to selection in dairy herds. In the
second part of this study, genetic parameters and correlations between fertility traits, sourced from
standard reproduction management data bases, are analysed for Holstein cows using bivariate linearlinear
and linear-threshold animal models. Insemination events (n = 69 181) from 26 645 lactations of
9 046 Holstein cows from 14 herds, calving down during the period from 1991 to 2007, were
available. The outcome of each AI event was known. Insemination records were linked to the calving
date of each cow, lactation number as well as dam and sire identification. Fertility traits indicating the
ability of cows to show heat early in the breeding period, and to become pregnant, were derived. Data were analysed using bivariate linear-linear and linear-threshold animal models with fixed effects being
herd (14 levels), year (17 levels), season (4 levels) and lactation number (6 levels). The model
included the random effects of animal and animal permanent environment (PE). Heritability estimates
ranged from 0.04±0.01 to 0.10±0.02 for FS80d, from 0.07±0.01 to 0.08±0.02 for PD100d and from
0.06±0.04 to 0.08±0.02 for PD200d depending on the two-trait combination. Although heritability
estimates of most fertility traits were below 0.10, they were in close agreement with results published
by other researchers using linear models. Genetic correlations between different fertility parameters
analyzed in this study indicated that it is unlikely that a single characteristic would serve well for
selection purposes; instead, combining different traits could be used in selection programmes to
improve fertility. Further research in constructing an optimal fertility index is warranted.
In the third part of this study, genetic parameters for South African Holstein cows for fertility and
production traits were estimated from 2415 lactation records. Two-trait analysis of fertility and milk
yield was investigated as a method to estimate fertility breeding values when culling, or selection
based on milk yield in early lactation, determines presence or absence of fertility observations in later
lactations. Fertility traits were days from calving to first service (CFS), days from calving to conception
(DO), percentage cows inseminated within 80d post-partum (FS80d), number of service per
conception (SPC), and the binary traits percentage of cows pregnant within 100d and 200d postpartum
(PD100d, Pd200d). Milk production traits were 300 day milk, fat and protein yield. For fertility
traits, range of estimates of heritability (h2) was 0.006 to 0.08 for linear traits and 0.05 to 0.12 for
binary traits. The range for permanent environmental variance (c2) was 0.016 to 0.032. In this study
genetic correlations of fertility with milk production traits were unfavourable ranging between −0.93 to 0.76. / AFRIKAANSE OPSOMMING: Winsgewende melkproduksie en genetiese verbetering in melkkuddes hang grootliks af van vrugbare
koeie wat op ‘n jaarlikse basis kalf. Verskeie studies toon dat die reproduksievermoë van
Holsteinkoeie oor die afgelope 30 jaar afgeneem het. Melkboere gebruik tussenkalfperiode (TKP) en
aantal inseminasies per konsepsie (KIPK) as aanduidings van die reproduksievermoë van melkkoeie.
Dit is egter moeilik om hierdie eienskappe as vrugbaarheidseienskappe vir melkkoeie te gebruik
omdat TKP afhanklik is van opeenvolgende kalfdatums terwyl KIPK baie sterk gekoppel is aan die
inseminasievermoë van die insemineerders. In die eerste gedeelte van die studie word alternatiewe
vrugbaarheidseienskappe, wat afgelei is van inseminasie- en kalfdatums en die uitslag van
dragtigheidsondersoeke, beskryf. Die invloed van ‘n aantal nie-genetiese faktore op dié eienskappe
word ook bespreek. Gemiddeldes±standaard afwykings vir die periode vanaf kalwing tot eerste
inseminasie (CFS), die periode van kalwing tot konsepsie (DO) was 77±30 en 134±74 dae
onderskeidelik, terwyl die aantal inseminasies per konsepsie (SPC) 2.55±1.79 was. Die persentasie
eerste inseminasies wat binne 80 dae na kalwing (FS80d), en die persentasie koeie wat dragtig
bevestig is binne 100 (PD100d) en 200 dae na kalwing (PD200d) was 0.64±0.48, 0.36±0.48 en
0.71±0.45, onderskeidelik. Hoewel vrugbaarheidseienskappe betekenisvol beïnvloed is deur
laktasienommer, jaar en seisoen van kalwing, het kuddes (bestuurders) die grootste effek op
eienskappe gehad.
Vrugbaarheid is ‘n ingewikkelde eienskap en die uitdaging is om eienskappe te vind wat dit die beste
beskryf. Genetiese parameters vir eienskappe wat oorweeg word sal ‘n aanduiding gee van die
seleksieresponse in melkkuddes. In die tweede gedeelte van die studie is genetiese parameters van
vrugbaarheidseienskappe en korrelasies tussen dié eienskappe beraam. Eienskappe is bekom vanaf
reproduksiebestuursprogramme wat in melkkuddes gebruik word. Al die inseminasierekords (n =
69 181) van 26 645 laktasies van 9 046 Holsteinkoeie van 14 melkkuddes wat tussen 1991 en 2007 gekalf het, was beskikbaar. Die uitslag van elke inseminasie was bekend. Inseminasierekords is met
die kalfdatum, laktasienommer, identifkasienommers van die moeder en vader van elke koei,
gekoppel. Vrugbaarheidseienskappe wat die vermoë van koeie aandui om vroeg na kalwing op hitte
te kom en beset te raak, is verkry. Die data is ontleed deur gebruik te maak van twee-eienskap liniêreliniêr-
en liniêr-drempel-diere modelle met vaste effekte kudde (14 vlakke), jaar (17 vlakke), siesoen (4
vlakke) en laktasienommer (6 vlakke). Die modelle het die ewekansige effekte van dier- en dierpermananente
omgewingseffkte (PE) ingesluit. Genetiese, diere PE en residuele korrelasies is
vervolgens beraam. Oorerflikhede varieer vanaf 0.04±0.01 tot 0.10±0.02 vir FS80d, vanaf 0.07±0.01
tot 0.08±0.02 vir PD100d en vanaf 0.06±0.04 tot 0.08±0.02 vir PD200d, afhangende van die tweeeienskap
kombinasie. Ten spyte daarvan dat die oorerflikhede van die meeste vrugbaarseienskappe
laer as 0.10 is, is die resultate in ooreenstemming met ander navorsers wat liniëre modelle gebruik
het. Genetiese korrelasies tussen verskillende vrugbaarheidseienskappe toon dat daar nie enkel
beste eienskap is wat vir seleksiedoeleindes gebruik kan word nie. Dit sou waarskynlik beter wees om
verskillende eienskappe te kombineer om die vrugbaarheid in melkkoeie te verbeter. Verdere
navorsing is nodig om ‘n optimale vrugbaarheidseienskap te ontwikkel.
Dit is belangrik dat die verband tussen reproduksie en melkproduksie vir melkkoeie bepaal word. In
die derde gedeelte van die studie is genetiese parameters vir vrugbaarheid- en melkproduksieeienskappe
vir Suid Afrikaanse Holsteinkoeie beraam. ‘n Totaal van 2415 laktasierekords was
beskikbaar. Vrugbaarheid en melkproduksie is volgens ‘n twee-eienskap analise ontleed as ‘n metode
om teelwaardes vir vrugbaarheid te bepaal in gevalle waar die uitskot of seleksie gebaseer op
melkproduksie in vroeglaktasie die teenwoordigheid of afwesigheid van vrugbaarheidseienskappe in
latere laktasies bepaal. Vrugbaarheidseienskappe was die periode (aantal dae) tussen kalfdatum en
eerste inseminasie (CFS), die aantal dae van kalf tot konsepsie (DO), die persentasie koeie wat by 80
dae na kalf vir die eerste keer geïnsemineer was (FS80d), die aantal inseminasies per konsepsie
(SPC), en binêre eienskappe van die persentasie koeie wat by 100 dae en 200 dae na kalf beset was
(PD100d en PD200d). Melkproduksie-eienskappe was 300-dae melk., vet- en proteïnproduksie. Vir
vrugbaarheidseienskappe het die oorerflikheidswaardes (h2) vanaf 0.006 tot 0.08 vir liniêre
eienskappe gevarieer en tussen 0.05 tot 0.12 vir binêre eienskappe. Die permanente
omgewingsvariansie (c2) het tussen 0.016 tot 0.032 gevarieer. In hierdie studie was die genetiese
korrelasies tussen vrugbaarheidseienskappe en melkproduksie-eienskappe ongunstig en het dit
tussen −0.93 tot 0.76 gevarieer.
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Négocier pour exister : les villes et les duchés du nord de l’Empire face à la France (1650-1730) / Negociate to exist. Diplomatic relations between the towns and the duchies of the Northern Holy Empire and France (1650-1730)Félicité, Indravati 31 March 2012 (has links)
La thèse explore le lien entre la politique étrangère et la survie politique et économique des villes hanséatiques (Hambourg, Brême et Lübeck) et des duchés de Mecklembourg-Schwerin et de Schleswig-Holstein-Gottorp de 1650 à 1730, à travers les relations diplomatiques entretenues par ces petits États avec la France. Les différentes stratégies qu’ils mettent en œuvre afin d’être considérés comme des partenaires diplomatiques par la France font l’objet de la première partie. La deuxième partie est consacrée aux pratiques de la négociation développées par ces États au contact de la France, à leur manière de communiquer avec cette puissance concurrente de l’autorité impériale, ainsi qu’à la prise de décision en matière de politique étrangère. La question de la souveraineté de ces États constitue le fil directeur de la réflexion : ces États, qui jouissent du droit de négocier avec les puissances étrangères à l’Empire, resten soumis à l’autorité de l’Empereur. La troisième partie pose la question de la professionnalisation de la fonction de diplomate dans l’Empire. Trois aspects sont développés. Les éléments permettant de parler de l’émergence d’un métier sont évoqués dans un premier temps, ainsi que les résistances des diplomates à cette première professionnalisation. La situation financière et la vie matérielle des diplomates permettent ensuite de poser la question de leur place dans la hiérarchie sociale de l’époque. Enfin, ces éléments sont complétés par un questionnement sur la culture des diplomates, notamment à travers les relations qu’ils entretiennent avec la République des Lettres et l’analyse de publications, littéraires ou savantes, qui leur sont consacrées. / Through the diplomatic relations maintained with France by the Hanseatic towns (Hamburg, Bremen and Lubeck) and the duchies of Mecklenburg-Schwerin and Schleswig-Holstein-Gottorp from 1650 to 1730 this thesis will explore the link between foreign policy on the one hand and economical and political survival on the other hand. Therefore, the strategies these states develop in order to make themselves considered as valuable partners by the French government form the first part of the thesis. The second part focuses first on the practice of negotiation these states elaborated in contact with France and then on the way they communicated with a power that challenged the authority of the Emperor. Finally the decision-making in the field of foreign policy is regarded. The question if these small states may really be considered as sovereign states is the leitmotif of this thesis as these small states and Hansestic towns are in fact allowed to negotiate with external powers of the Empire. The third part deals with the diplomatic profession. The question is if the function of a diplomat is becoming a genuine profession or not. To this, three topics are studied: the elements which show that the function of a diplomat is indeed becoming a career is presented first as well as the powers of resistance to this evolution. In a second step the financial situation and the material life of the diplomats allow to examine the place of the diplomats in the social hierarchy. These subjects are at last completed by a closer look on the culture of the diplomats through their close ties to the Republic of Letters and the analysis of literary and scientific publications dedicated to their action.
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The effect of Fleckvieh crossbreeding in dairy cattle on the conjugated linoleic acid content of milk produced in intensive and pasture-fed systemsSasanti, Babalwa January 2015 (has links)
Thesis submitted in fulfilment of the requirements for the degree of Magister Technologiae: Agriculture in the Faculty of Applied Sciences at the Cape Peninsula University of Technology / Conjugated linoleic acid (CLA), a fatty acid (FA) present in the meat and milk of ruminant
animals, is considered a functional nutrient for humans. The interest in CLA is attributed to its
many health benefits, such as having anti-carcinogenic, anti-atherogenic, anti-diabetic and
anti-adipogenic effects. Dairy products are a rich natural source of CLA, and preliminary
research indicates that the levels in milk can vary based on cattle breed and feeding system.
The Fleckvieh is a popular dual-purpose breed recently introduced to the Western Cape. It is
used in crossbreeding programs with Holstein and Jersey herds to increase fertility and beef
production. Holstein and Jersey cattle are the two most common South African dairy breeds,
but little information is available on the effect of crossbreeding on FA content and CLA levels
in the milk. The primary objective of this study was to compare milk FA composition and CLA
content of these two dairy breeds and their respective Fleckvieh crosses. A second objective
was to investigate the effect of lactation stage on CLA levels. Jersey (J) and Fleckvieh x
Jersey (F×J) cows were kept in a pasture-based system (PBS) for the duration of the study.
Holstein (H) and Fleckvieh x Holstein (F×H) cows were housed in a feedlot system and fed a
total mixed ration (TMR) for the duration of the study. The FA and CLA content of feeds from
these two feeding systems were also analysed and compared. All cows used in the study
were housed at the Elsenburg Research Farm of the Western Cape Department of
Agriculture.
Milk samples were collected every 35 days from the cows in each feeding group, starting 10
days after calving. Samples were kept in a freezer at -20 °C until laboratory analyses. The
total number of milk samples collected was 1044. The milk FA composition and CLA in
particular were determined by gas chromatography. Differences between groups were
statistically analysed by two-way repeated measures of analysis of variance (ANOVA).
Results show that milk CLA levels are higher in Fleckvieh-crossbred cows when compared to
purebred cows. The higher CLA content of milk from Fleckvieh crossbred cows demonstrates
the feasibility of using Fleckvieh bulls in South African crossbreeding programs, and are also
an indication that genetic selection for increased CLA content is possible. The analysis of
lactation stage showed that milk CLA is higher during late lactation. A comparison of feed
samples from the two feeding systems revealed that pasture feeding resulted in higher
omega-3 FA in milk.
Key words: Conjugated linoleic acid, milk fatty acids profile, diet, breed, health benefits,
Fleckvieh, Holstein, Jersey, diet, pasture based system, total mixed ration system,
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Inseminação artificial em tempo fixo em vacas holandesas de alta produção / Timed artificial insemination in high producing holstein cowsSouza, Alexandre Henryli de 26 March 2008 (has links)
A presente tese foi dividida em 5 Experimentos. Os objetivos do Experimento 1 foram avaliar a utilização da gonadotrofina coriônica equina (eCG) e/ou do cipionato de estradiol (ECP) na dinâmica folicular e taxa de concepção de vacas holandesas submetidas a inseminação em tempo fixo (IATF). No D0, todos os animais (n = 782) receberam 2 mg de benzoato de estradiol (BE) e um dispositivo intravaginal de progesterona (CIDR). Oito dias depois, o CIDR foi retirado e todos os animais receberam PGF2?. Simultaneamente, os animais foram divididos em 4 grupos: G1) eCG + ECP no Dia 8; G2) eCG no Dia 8 + GnRH após 48h; G3) ECP no Dia 8; G4) GnRH após 48h. Amostras de sangue e exames utlra-sonográficos foram realizados frequentemente em um subgrupo de animais (n = 96). As análises estatísticas de todos os experimentos foram efetuadas com o proc GLIMMIX e proc MIXED do SAS. O uso de eCG e o escore de condição corporal (ECC) dos animais afetaram as concentrações circulantes de progesterona no diestro. Os animais do G2 apresentaram maior taxa de concepção que os do G4 (33,8% vs. 28,9%). Além disso, para animais de menor ECC, ficou evidente o benefício da aplicação de eCG (G2 = 44,4% vs. G4 = 6,1%). No Experimento 2 (n = 26), o objetivo foi comparar o efeito da administração da eCG no dia da remoção do CIDR em animais de menor (2,0-2,5) ou maior (3,0-3,5) ECC. Foram avaliadas algumas características do corpo lúteo (CL) como o volume e histologia, assim como as concentrações plasmáticas de progesterona no diestro. Independentemente da condição corporal dos animais, a eCG aumentou o volume do CL e a concentração plasmática de progesterona no diestro. O ECC afetou negativamente o volume e concentração de progesterona sérica no diestro. Não foi encontrado diferença na proporção de células grandes/pequenas, assim como no fluxo sanguíneo no CL entre os grupos experimentais. No Experimento 3, foi comparado a taxa de concepção em vacas de leite de alta produção (n = 388) após o uso do protocolo G2 do Experimento 1 (Capítulo I), com ou sem adição de ECP no momento da retirada do CIDR (novo ou usado). Não foi verificado efeito da adição do tratamento com ECP e nem do tipo do dispostivo na taxa de concepção. No Experimento 4 (n = 199), apesar no aumento verificado no diâmetro folicular no grupo tratado com GnRH 56h (17,8 mm) comparado com GnRH 48h (16,5 mm); e do atraso no momento da ovulação após a retirada do CIDR (GnRH 56h = 75,3h; GnRH 48h = 79,8h) não foi constatado qualquer diferença na concepção ao se atrasar a aplicação do GnRH de 48h para 56h em vacas inseminadas 16h depois do GnRH. No Experimento 5 (n = 185), a taxa de concepção não diferiu em animais que receberam o GnRH 48h ou 56h (momento da IATF) após a retirada do CIDR, indicando a possibilidade do emprego de um protocolo com apenas 3 manejos em vacas de leite de alta produção. / The current thesys has been divided in 5 Experiments. Objectives of Experiment 1 were to evaluate the effects of equine chorionic gonadotropin (eCG) and/or estradiol cypionate (ECP) on follicular dymanics and conception rate in Holstein cows receiving fixed timed artificial insemination (TAI). On D0, all cows (n = 782) received 2 mg of estradiol benzoate (EB) and one intravaginal progesterone device (CIDR). Eight days later, CIDR was removed and all animals were treated with PGF2?. Simultaneously, animals were divided in 4 groups: G1) eCG + ECP on Day 8; G2) eCG on Day 8 + GnRH 48h later; G3) ECP on Day 8; G4) GnRH 48h later. Blood samples and ultrasound exams were frequently performed in a subset of the animals (n = 96). All the statistical analyses for all experiments were performed with proc GLIMMIX and proc MIXED of SAS. Equine chorionic gonadotropin (eCG) treatment and body condition score (BCS) affected circulating progesterone in the diestrus. Cows in G2 had greater conception rates than cows in G4 (33,8% vs. 28,9%). In addition, in cows with lower BCS, eCG seems to be even more affective (G2 = 44,4% vs. G4 = 6,1%). In Experiment 2 (n = 26), the objective was to compare the effect of eCG the day of CIDR removal in animals with lower (2,0-2,5) or higher (3,0-3,5) BCS. Some variables such as corpus luteum (CL) volume, histology and circulating progesterone concentration in the diestrus were evaluated. Regardless of the body condition of the animals, eCG increased CL volume and circulating progesterone concentration in the diestrus. BCS negatively affected CL volume and circulating progesterone. There were no differences in large/small CL cell ratio, as well as CL blood flow between experimental groups. In Experiment 3, it was compared conception rate in dairy cows (n = 388) after using the same protocol G2 from Experiment 1 (Chapter I), with or without an ECP treatment at the time of CIDR (new or used) removal. Both ECP treatment and type of CIDR did not significantly affected conception rates. In Experiment 4 (n = 199), despite the fact that follicular diameter was increased in group GnRH 56h (17,8 mm) compared with GnRH 48h (16,5 mm); and of the delayed time of ovulation after CIDR removal (GnRH 56h = 75,3h; GnRH 48h = 79,8h), there were no differences in conception rates after delaying the GnRH treatment from 48h to 56h in cows inseminated 16h after GnRH. In Experiment 5 (n = 185), conception rate did not differ in animals that received GnRH 48h or 56h (at the time of TAI) after CIDR removal, indicating the possibility of using a protocol with only 3 handlings in high producing dairy cows.
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Perfil lipídico do plasma de vacas leiteiras segundo abordagem \"ômica\" e sua relação com desempenho reprodutivo / Lipid profile in plasma of dairy cows second approach \"omics\" and its relationship to reproductive performanceNaves, Julianne de Rezende 19 June 2015 (has links)
O objetivo deste estudo foi analisar o plasma sanguíneo correspondente ao período de transição, de vacas Holandesas de alta produção e sua relação com o desempenho reprodutivo. Para isso, este plasma foi analisado com emprego do equipamento de espectrômetro de massas híbrido triplo quadrupolo/tempo-de-vôo, para identificação dos Lipídios. As alterações metabólicas e hormonais ocorridas durante esta fase, nas vacas leiteiras, afetam diretamente a saúde e o desempenho produtivo e reprodutivo das mesmas. Nesse período, ocorre o balanço energético negativo, caracterizado pelo aumento da mobilização de reservas energéticas, normalmente do tecido adiposo, para atender às demandas voltadas à produção de leite. Neste projeto, propõe-se o estudo da condição metabólica, principalmente sob um contexto lipidômico, durante o período de transição e início de lactação de vacas leiteiras em dois grupos de produção (Alta: ≥ 45,9 kg leite/dia e Média: 30-45,8kg leite/dia), nos períodos de Inverno e Verão que se tornaram prenhes ou não aos 150 dias de experimento (após 3 IATF), em um contexto multidisciplinar, visando o melhor entendimento, tanto do desempenho produtivo, como do reprodutivo e na elaboração de estratégias de manejo, para aplicação nos rebanhos leiteiros no Brasil. Foram utilizadas 31 vacas da raça Holandesa, multíparas e gestantes, com parto previsto para 21 dias após o início do período de avaliação experimental. Os animais foram avaliados durante o período pré-parto até 150 dias de lactação. Nas amostras foram analisadas variáveis plasmáticas, conhecidamente ligadas às condições metabólicas (energética, proteica e enzímica). Estes valores serão utilizados como guias na utilização da abordagen ômica (lipidômica), com finalidade de identificar biomarcadores lipídicos descritivos do metabolismo destes animais. Todos os dados obtidos foram analisados por métodos estatísticos convencionais e por estatística multivariada, utilizando técnicas como PCA (Principal Component Analisis) e OPLS (Orthogonal Projection on Latent Structures) e ferramentas de bioinformática, a fim de identificar quais metabólitos são mais descritivos do metabolismo destes animais, bem como a interação das diferentes vias metabólicas. Concluí-se que ao final do período de transição, o plasma de vacas pós-parto que contenham maiores quantidades de fosfatifilcolinas, principalmente 36:2 e 36:4, podem obter melhores chances de se tornarem prenhes à 1IATF. Estas fosfatidilcolinas podem ser consideradas como bons biomarcadores lipídicos devido à sua interferência com a maior síntese de lipoproteínas VLDL, evitando assim, a ocorrência de fígado gorduroso, característico desse período. Além disso, estas moléculas podem auxiliar no processo de monitoramento de alguns parâmetros metabólicos alterados, normalmente observados durante o balanço energético negativo / The aim of this study was to analyze the corresponding blood plasma in transitional period of Holstein cows with high production and its relation to the reproductive performance. Therefore, this plasma was analyzed with the use of a triple quadrupole mass spectrometer time-of-flight, for identification of lipids. In dairy cows, the metabolic and hormonal changes during this phase, directly affect the health and productive and reproductive performance. In this period, the negative energy balance is characterized by increased mobilization of energy reserves, usually by fat, due the demands on milk production. In this project, we proposed the study of metabolic condition, especially under a lipidomic context, during the transition period and early lactation dairy cows on two milk productions (High: ≥ 45.9 kg milk/day and Medium: 30 -45,8kg milk/day) during the periods, winter and summer, of cows that became pregnant or not in the 150 days of the experiment (after 3 IATF), in a multidisciplinary context, for get better understand the both productions performances, the reproductive and developing management strategies for application in dairy herds in Brazil. They used 31 Holstein cows, multiparous and pregnants, with calving expected to 21 days after the beginning of the experimental evaluation period. The animals were evaluated during ante partum period to 150 days of lactation. Samples were analyzed by parameters, known to be linked to metabolic conditions (energy, protein and enzyme). These values will be used as guides in a ohmic approach (lipidomics), with the purpose of identifying biomarkers describe lipid metabolism of these animals. All data were analyzed by conventional statistical methods and multivariate statistics, using techniques such as PCA (Principal Component Analysis) and OPLS (Orthogonal Projection on Latent Structures) and bioinformatics tools to identify which metabolites are more descriptive of the metabolism of these animals as well as the interaction of different metabolic pathways. It can be concluded that the end of the transition period, the plasma post-partum cows containing larger amounts of phosphatidylcholines, especially 36:2 and 36:4, may best chance of becoming pregnant in 1IATF. These phosphatidylcholines may be considered a good lipid biomarkers interfering with the highest synthesis of VLDL, thereby avoiding the occurrence of fatty liver characteristic of that period. Therefore, these molecules can be used for monitoring the process of change of some metabolic parameters normally observed during negative energy balance
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