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See detailCompiling polymorphic miRNA-target interactions: the Patrocles database.
Hiard, Samuel ULg; Tordoir, Xavier ULg; Coppieters, Wouter ULg et al

Poster (2007, November 12)

Using positional cloning, we have recently identified the mutation responsible for muscular phenotype of the Texel sheep. It is located in the 3’UTR of the GDF8 gene - a known developmental repressor of ... [more ▼]

Using positional cloning, we have recently identified the mutation responsible for muscular phenotype of the Texel sheep. It is located in the 3’UTR of the GDF8 gene - a known developmental repressor of muscle growth - and creates an illegitimate target site for miRNA expressed in the same tissue. This causes miRNA-mediated translation inhibition of mutant GDF8 transcripts which leads to muscle hypertrophy. We followed up on this finding by searching for common polymorphisms and mutations that affect either (i) RNAi silencing machinery components, (ii) miRNA precursors or (iii) target sites. These might likewise alter miRNA-target interaction and could be responsible for substantial differences in gene expression level. They have been compiled in a public database (“Patrocles”: www.patrocles.org), where they are classified in (i) DNA sequence polymorphisms (DSP) affecting the silencing machinery, (ii) DSP affecting miRNA structure or expression and (iii) DSP affecting miRNA target sites. DSP from the last category were organized in four classes: destroying a target site conserved between mammals (DC), destroying a non-conserved target site (DNC), creating a non-conserved target site (CNC), or shifting a target site (S). To aid in the identification of the most relevant DSP (such as those were a target site is created in an antitarget gene), we have quantified the level of coexpression for all miRNA-gene pairs. Analysis of the numbers of Patrocles-DSP as well as their allelic frequency distribution indicates that a substantial proportion of them undergo purifying selection. The signature of selection was most pronounced for the DC class but was significant for the DNC and CNC class as well, suggesting that a significant proportion of non-conserved targets is truly functional. The Patrocles database allowed for the selection of DSP that are likely to affect gene function and possibly disease susceptibility. The effect of these DSP is being studied both in vitro and in vivo. In conclusion, Patrocles-DSP could be widespread and underlie an appreciable amount of phenotypic variation, including common disease susceptibility. [less ▲]

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See detailCompiling polymorphic miRNA-target interactions: the Patrocles database.
Hiard, Samuel ULg; Tordoir, Xavier ULg; Coppieters, Wouter ULg et al

Poster (2007, February 15)

Using positional cloning, we have recently identified the mutation responsible for muscular phenotype of the Texel sheep. It is located in the 3’UTR of the GDF8 gene - a known developmental repressor of ... [more ▼]

Using positional cloning, we have recently identified the mutation responsible for muscular phenotype of the Texel sheep. It is located in the 3’UTR of the GDF8 gene - a known developmental repressor of muscle growth - and creates an illegitimate target site for miRNA expressed in the same tissue. This causes miRNA-mediated translation inhibition of mutant GDF8 transcripts which leads to muscle hypertrophy. We followed up on this finding by searching for common polymorphisms and mutations that affect either (i) RNAi silencing machinery components, (ii) miRNA precursors or (iii) target sites. These might likewise alter miRNA-target interaction and could be responsible for substantial differences in gene expression level. They have been compiled in a public database (“Patrocles”: www.patrocles.org), where they are classified in (i) DNA sequence polymorphisms (DSP) affecting the silencing machinery, (ii) DSP affecting miRNA structure or expression and (iii) DSP affecting miRNA target sites. DSP from the last category were organized in four classes: destroying a target site conserved between mammals (DC), destroying a non-conserved target site (DNC), creating a non-conserved target site (CNC), or shifting a target site (S). To aid in the identification of the most relevant DSP (such as those were a target site is created in an antitarget gene), we have quantified the level of coexpression for all miRNA-gene pairs. Analysis of the numbers of Patrocles-DSP as well as their allelic frequency distribution indicates that a substantial proportion of them undergo purifying selection. The signature of selection was most pronounced for the DC class but was significant for the DNC and CNC class as well, suggesting that a significant proportion of non-conserved targets is truly functional. The Patrocles database allowed for the selection of DSP that are likely to affect gene function and possibly disease susceptibility. The effect of these DSP is being studied both in vitro and in vivo. In conclusion, Patrocles-DSP could be widespread and underlie an appreciable amount of phenotypic variation, including common disease susceptibility. [less ▲]

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See detailComplement activation during cardiopulmonary bypass in infants and children: Relation to postoperative multiple system organ failure
Seghaye, Marie-Christine ULg; Duchateau, J.; Grabitz, R. G. et al

in Journal of Thoracic and Cardiovascular Surgery (1993), 106(6), 978-987

Twenty-nine children 3 months to 17 years of age undergoing operations for congenital heart disease were included in this prospective study. Complement activation, activation of the plasma contact system ... [more ▼]

Twenty-nine children 3 months to 17 years of age undergoing operations for congenital heart disease were included in this prospective study. Complement activation, activation of the plasma contact system, leukocytes, leukocyte elastase release, and C-reactive protein were studied during and after cardiopulmonary bypass for the first postoperative week and related to multiple system organ failure occurring in eight (27.5 %) of the 29 children. During cardiopulmonary bypass complement activation via the alternative pathway as indicated by significant conversion of C3 (expressed by C3d/C3) and abnormally high C5a values at the end of cardiopulmonary bypass without consumption of C4 was shown in all children. At the end of cardiopulmonary bypass, C3 conversion was significantly higher in the eight patients with multiple system organ failure than in the others (p < 0.05), whereas no difference in C5a level was shown. All children had a significant increase in leukocyte count directly after protamine administration (p < 0.0001) and elastase release during cardiopulmonary bypass that was significantly higher in patients with multiple system organ failure than in those without (p < 0.05). Consumption of prekallikrein as an indicator of activation of the Hageman system was not detectable during cardiopulmonary bypass in any child. After cardiopulmonary bypass, in patients without multiple system organ failure, C3d/C3 decreased and reached preoperative values within the first postoperative week, whereas, in patients with multiple system organ failure, C3d/C3 increased further, reaching a maximal value on the third postoperative day. In comparison with patients without multiple system organ failure, patients with multiple system organ failure showed a severe decrease of C4 (with minimal values on the third postoperative day), suggesting consumption by activation of the classic pathway of the complement system or a hepatic synthesis deficiency. Prekallikrein values were also significantly lower in patients with multiple system organ failure than in the others, with a maximal difference on the third postoperative day (p < 0.005). C-reactive protein was significantly lower in patients with multiple system organ failure than in the others for the first 2 postoperative days (p < 0.05), probably because of severe hepatic failure in patients with multiple system organ failure. This study demonstrates that, in children, cardiopulmonary bypass induces complement activation principally via the alternative pathway. It suggests a relationship between complement activation and multiple system organ failure observed in the postoperative period. Furthermore, it points out the role of multiple system organ failure itself on the C3 conversion and on the synthesis of the markers of the inflammatory response in children after heart operations. [less ▲]

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See detailComplement activation during hemodialysis
Malaise, Michel ULg; Lust, Catherine ULg; Foidart, J. B. et al

in New England Journal of Medicine [=NEJM] (1985), 312(8), 514-515

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See detailComplement activation in patients at risk of developing the adult respiratory distress syndrome.
Duchateau, J.; Haas, M.; Schreyen, H. et al

in American Review of Respiratory Disease (1984), 130(6), 1058-64

In this prospective study of 50 patients, 36 of whom developed the adult respiratory distress syndrome (ARDS), early and intense complement activation was demonstrated. These patients were at risk of the ... [more ▼]

In this prospective study of 50 patients, 36 of whom developed the adult respiratory distress syndrome (ARDS), early and intense complement activation was demonstrated. These patients were at risk of the ARDS because of multiple injuries, major abdominal surgery, acute pancreatitis, severe burns, or disseminated intravascular coagulation. Abnormal C3 consumption (as measured by the C3d/C3 ratio) and elevated plasma C5a-like activity (as measured by a leukocyte aggregation assay) were associated with, respectively, 84 and 86% of cases of ARDS. Both tests were more sensitive indicators of complement consumption than were assays of total hemolytic complement activity (CH50) or total C3. The C3d/C3 ratio showed a close, inverse correlation with CH50 in 47 healthy subjects, and was increased in 12 control patients after minor surgery. The C5a-like activity was found only in patients at risk of ARDS; it was highly associated with clinical conditions that predispose to the ARDS, but it cannot be considered as a real predictor of ARDS occurrence in these patients. Sequential samples from both sides of the pulmonary circulation showed initial pulmonary clearance followed by the release of C5a-like activity. No simultaneous changes in C3 levels were found, suggesting the possible presence of modulating factors. These observations suggest that other factors (e.g., hypoxia and metabolic cascades) may influence the development of ARDS. [less ▲]

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See detailComplément au rapport final de synthèse du projet 4M-µpompe 2004
Raucent, Benoit; Dereine, E.; Smal, Olivier et al

Report (2004)

The 4M-µpump project attempts to breach the gap between traditional mechanics and micro mechanics and this in two ways. The first one consists in producing a general set of rules suitable for the ... [more ▼]

The 4M-µpump project attempts to breach the gap between traditional mechanics and micro mechanics and this in two ways. The first one consists in producing a general set of rules suitable for the miniaturisation of well-known macromachines. The second one consists in developing this fundamental aspect of the research through the design and realization of an implantable pump dedicated to the administration of medication agents inside the human body. The project thus touches upon the field of design, manufacturing, metrology and assembly of mini components as well as the study of minimotors. [less ▲]

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See detailComplément d'épidémiologie
Bruyère, Olivier ULg

Learning material (2011)

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See detailComplement extraposition: what is it a diagnostic of?
Gentens, Caroline; Brems, Lieselotte ULg

Conference (2013, May)

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See detailLe complément sujet : Etude de l'utilisation des pronoms moi et je dans le discours d'enfants âgés de 2 ans et demi à 10 ans.
Boulard, Aurore ULg; Gauthier, Jean-Marie ULg

in Bolasco, Sergio; Chiari, Isabella; Giuliano, Luca (Eds.) Statistical Analysis of Textual Data: Proceedings of 10th International Conference Journées d’Analyse statistique des Données Textuelles 9-11 June 2010 - Sapienza University of Rome (2010)

Grâce à l’analyse statistique discursive d’un corpus constitué du discours de 90 enfants, nous avons pu observer l’évolution de l’utilisation des pronoms personnels moi et je et mettre en évidence ... [more ▼]

Grâce à l’analyse statistique discursive d’un corpus constitué du discours de 90 enfants, nous avons pu observer l’évolution de l’utilisation des pronoms personnels moi et je et mettre en évidence certaines variations d’utilisation en fonction de l’âge et de trois conditions d’enregistrement. Le protocole de recherche utilisé nous permet de laisser le sujet libre de s’exprimer. Aucun thème n’a été proposé aux enfants. « En recueillant paroles et textes libres, le chercheur accède à tout l’univers du sujet, riche de sa singularité individuelle et de son appartenance culturelle et sociale. » (Moscarola, 2001). Ce n’est pas le développement du langage qui est étudié mais bien le discours qui, selon nous, permet un accès au sens, aux structures psychiques de l’individu. L’analyse du discours nous permet d’étudier le développement de la conscience de soi grâce à une méthodologie simple et non contraignante pour les enfants. Cette recherche trouve son originalité dans le croisement des résultats de l’analyse statistique textuelle (Lexico3, Tropes) avec les théories du développement de la conscience de soi. Les résultats de ces analyses nous montrent que dès l’instant où le je apparaît, le moi auparavant utilisé seul en tant que sujet se transforme en complément du sujet-je. En tant que complément du sujet, il objective le sujet parlant, lui permettant une mise à distance. Le sujet peut donc se regarder agir, faire où être en tant qu’objet. La forme moi-je, également fréquente dans le discours de l’enfant, est pour nous, sans doute, la forme réflexive la plus claire de l’avènement de la conscience de soi se manifestant par le biais du discours narratif autobiographique. Plus tard dans le discours de l’enfant, le je va pouvoir exister seul. Notre hypothèse est qu’étant davantage conscient de lui-même, l’enfant n’aurait plus systématiquement recours à la projection de son moi pour prendre conscience de son existence en tant qu’être parmi les autres. [less ▲]

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See detailComplement, leukocytes, and leukocyte elastase in full-term neonates undergoing cardiac operation.
SEGHAYE, Marie-Christine ULg; Duchateau, J.; Grabitz, R. G. et al

in Journal of Thoracic and Cardiovascular Surgery (The) (1994), 108(1), 29-36

In 13 neonates undergoing cardiac operations for congenital cardiac defects, complement, leukocytes, and leukocyte elastase were studied during and after cardiopulmonary bypass. All but two neonates ... [more ▼]

In 13 neonates undergoing cardiac operations for congenital cardiac defects, complement, leukocytes, and leukocyte elastase were studied during and after cardiopulmonary bypass. All but two neonates received prostaglandin E1 before the operation. The C3d/C3 ratio rose significantly during cardiopulmonary bypass from 0.86 +/- 0.55 to 1.40 +/- 0.56 (mean +/- standard deviation; p < 0.0001). Abnormally elevated C5a levels (18.6 +/- 7.3 micrograms/L) were measured at the end of cardiopulmonary bypass. C4 was not overtly consumed during the procedure. Leukocytes fell from a preoperative value of 10.06 +/- 3.15 x 10(9)/L to 3.21 +/- 0.64 x 10(9)/L after beginning of cardiopulmonary bypass (p < 0.0001) and rose at the end of the procedure from 2.33 +/- 0.67 x 10(9)/L to 7.19 +/- 1.84 x 10(9)/L, after protamine administration (p < 0.0001). Neutrophils fell from a preoperative value of 5.14 +/- 1.18 x 10(9)/L to 1.46 +/- 0.35 x 10(9)/L after beginning of cardiopulmonary bypass and rose at the end of extracorporeal circulation from 1.00 +/- 0.31 x 10(9)/L to 4.10 +/- 1.18 x 10(9)/L, after protamine administration (p < 0.005). Elastase release occurred in all neonates during cardiopulmonary bypass and averaged 331.5 +/- 175.7 micrograms/L. Complement activation and leukocyte stimulation did not correlate with postoperative complications or outcome. This study demonstrates complement activation and leukocyte stimulation in neonates undergoing cardiac operation. [less ▲]

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See detailComplémentarité des systèmes d'étanchéité-drainage en matériaux naturels et synthétiques dans le confinement des déchets
Courard, Luc ULg

in De Paepe, Robert (Ed.) Les géotextiles et géomembranes dans les travaux fluviaux et maritimes (1997)

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See detailComplementary approaches to measure environmental odours emitted by landfill areas
Romain, Anne-Claude ULg; Delva, Julien ULg; Nicolas, Jacques ULg

in Sensors and actuators. B, Chemical (2008), 131(1), 18-23

This paper presents different methods to assess the odour emission and the odour annoyance in the surroundings. It is shown, on the example of landfill areas and composting facilities, that chemical ... [more ▼]

This paper presents different methods to assess the odour emission and the odour annoyance in the surroundings. It is shown, on the example of landfill areas and composting facilities, that chemical analyses are helpful to identify key compounds of the odour release, and to set up the specification of a monitoring instrument. Sensitive methods, like dynamic olfactometry or sniffing team investigation, are mainly applicable to provide a global odour plume or an average annoyance zone. And the electronic nose can supply a warning signal to the plant manager or a real time estimation of the annoyance zone. [less ▲]

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See detailComplementary Feeding: A Commentary by the ESPGHAN Committee on Nutrition
Agostoni, Carlo; Decsi, Tamas; Fewtrell, Mary et al

in Journal of Pediatric Gastroenterology and Nutrition (2008), 46(1), 99-110

This position paper on complementary feeding summarizes evidence for health effects of complementary foods. It focuses on healthy infants in Europe. After reviewing current knowledge and practices, we ... [more ▼]

This position paper on complementary feeding summarizes evidence for health effects of complementary foods. It focuses on healthy infants in Europe. After reviewing current knowledge and practices, we have formulated these conclusions: Exclusive or full breast-feeding for about 6 months is a desirable goal. Complementary feeding (ie, solid foods and liquids other than breast milk or infant formula and follow-on formula) should not be introduced before 17 weeks and not later than 26 weeks. There is no convincing scientific evidence that avoidance or delayed introduction of potentially allergenic foods, such as fish and eggs, reduces allergies, either in infants considered at increased brisk for the development of allergy or in those not considered to be at increased risk. During the complementary feeding period, > 90% of the iron requirements of a breast-fed infant must be met by complementary foods, which should provide sufficient bioavailable iron. Cow's milk is a poor source of iron and should not be used as the main drink before 12 months, although small volumes may be added to complementary foods. It is prudent to avoid both early (< 4 months) and late ( >= 7 months) introduction of gluten, and to introduce gluten gradually while the infant is still breast-fed, inasmuch as this may reduce the risk of celiac disease, type 1 diabetes mellitus, and wheat allergy. Infants and young children receiving a vegetarian diet should receive a sufficient amount (similar to 500 mL) of breast milk or formula and dairy products. Infants and young children should not be fed a vegan diet. [less ▲]

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See detailComplementary role of thallium-201 scintigraphy to predischarge exercise electrocardiography for patients stratification after a first myocardial infarction.
Legrand, Victor ULg; Albert, Adelin ULg; Rigo, Pierre ULg et al

in European Heart Journal (1986), 7(8), 644-53726

The value of a predischarge exercise test combined with thallium-201 myocardial scintigraphy in detecting patients with severe multivessel disease (MVD) was studied in 58 consecutive patients discharged ... [more ▼]

The value of a predischarge exercise test combined with thallium-201 myocardial scintigraphy in detecting patients with severe multivessel disease (MVD) was studied in 58 consecutive patients discharged after a first acute myocardial infarction. Twelve electrocardiographic, clinical and scintigraphic variables were analysed. Angiography at one month revealed MVD (greater than 70% narrowing in vessels unrelated to infarction) in 26 patients (45%). ST segment depression of 1mm or greater, thallium defects in multiple vascular distributions (MVTL), and reversible thallium defects in a vascular distribution different from the infarct related vessel predicted patients at risk for MVD (predictive value respectively of 68%, 65% and 75%). The other variables were not significantly associated with the presence of MVD. Only ST segment depression and thallium defects in multiple vascular distributions emerged as independent predictors of MVD. Their combination yielded a 77% sensitivity and a 59% specificity for MVD. Combination of thallium imaging with the predischarge exercise ECG significantly improved the stratification provided by the exercise test alone (P less than 0.05). A positive thallium scan (MVTl defects) associated with a positive ECG (ST depression) carried a risk for MVD of 80% in the population studied. When both tests were negative, MVD was infrequent (risk 22%). Because improvement in the stratification of patients is not as clear as expected from studies performed at a later stage, it appears that exercise thallium scintigraphy at a submaximal level one or two weeks after infarction does not provide optimal information. Predischarge exercise thallium-201 scintigraphy, however, is superior to an exercise tolerance test alone in separating patients into those with high and low risk of MVD. [less ▲]

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See detailThe complementary strand of the human T-cell leukemia virus type 1 RNA genome encodes a bZIP transcription factor that down-regulates viral transcription.
Gaudray, Gilles ULg; Gachon, Frederic; Basbous, Jihane et al

in Journal of virology (2002), 76(24), 12813-22

The RNA genome of the human T-cell leukemia virus type 1 (HTLV-1) codes for proteins involved in infectivity, replication, and transformation. We report in this study the characterization of a novel viral ... [more ▼]

The RNA genome of the human T-cell leukemia virus type 1 (HTLV-1) codes for proteins involved in infectivity, replication, and transformation. We report in this study the characterization of a novel viral protein encoded by the complementary strand of the HTLV-1 RNA genome. This protein, designated HBZ (for HTLV-1 bZIP factor), contains a N-terminal transcriptional activation domain and a leucine zipper motif in its C terminus. We show here that HBZ is able to interact with the bZIP transcription factor CREB-2 (also called ATF-4), known to activate the HTLV-1 transcription by recruiting the viral trans-activator Tax on the Tax-responsive elements (TxREs). However, we demonstrate that the HBZ/CREB-2 heterodimers are no more able to bind to the TxRE and cyclic AMP response element sites. Taking these findings together, the functional inactivation of CREB-2 by HBZ is suggested to contribute to regulation of the HTLV-1 transcription. Moreover, the characterization of a minus-strand gene protein encoded by HTLV-1 has never been reported until now. [less ▲]

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See detailComplementation of Saccharomyces cerevisiae mutants using a soil metatranscriptomic library
Kellner, Harald ULg; Luis, Patricia; Portetelle, Daniel ULg et al

Poster (2010, May 21)

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See detailComplémentation précoce en colostrum de vache Azawak chez la chèvre rousse de Maradi au Niger: effets sur les performances de croissance et de reproduction, et sur la survie au cours de la première année de vie.
Abdou, Harouna ULg

Doctoral thesis (2014)

L’élevage  des  petits  ruminants  représente  au  Niger,  la  ressource  principale  pour  plus  de  6  millions  de   paysans pauvres, vivant avec moins de 1 dollar US par jour. C'est un trésor ... [more ▼]

L’élevage  des  petits  ruminants  représente  au  Niger,  la  ressource  principale  pour  plus  de  6  millions  de   paysans pauvres, vivant avec moins de 1 dollar US par jour. C'est un trésor important qui contribue à la renommée des familles. Selon le recensement général  de  l’agriculture  et  de  l’élevage  (2007),  le   cheptel Nigérien se chiffre à 31 millions toutes espèces confondues dont 11 millions de caprins (36,21 %)  et  9  millions  d’ovins  (30  %). Bien  qu'il  occupe  une  place  de  choix,  l’élevage  des  petits  ruminants  reste confronté à des contraintes dont les principales sont: les sécheresses chroniques et répétitives ayant pour conséquence un déficit alimentaire constant, la pression démographique entrainant une concurrence entre les cultures et les animaux   pour   l’occupation de la terre et enfin les pathologies récurrentes (parasitoses gastro- intestinales, affections digestives) accompagnées le plus souvent par des diarrhées. Par ailleurs, la naissance et le sevrage sont deux périodes critiques pour les jeunes animaux. Si à la naissance, le système immunitaire reste en chantier et par conséquent déficient, au sevrage c'est le changement alimentaire qui peut handicaper la croissance des jeunes. Malheureusement, ils ne reçoivent pas toujours   toute   l’attention   et   la   vigilance nécessaire pour optimaliser leur développement. Dans ce contexte,   il   serait   intéressant   d’étudier   les   solutions   possibles   à   ces   problèmes.   L’utilisation   du   colostrum bovin semble être exploitable dans la mesure où il renferme des éléments nutritifs et antimicrobiens  nécessaires  pour  le  bovin,  mais  également  pour  d’autres  espèces  (caprins,  ovins,  porcs,   homme). Pour cette étude, le choix du colostrum bovin a été guidé aussi par sa disponibilité à la station sahélienne expérimentale de Toukounous au Niger. À priori, l’objectif de cette thèse est de vérifier l'hypothèse d'un effet bénéfique de l'administration du colostrum bovin sur la santé et les performances zootechniques des cabris. Le   premier   chapitre   présente   d’abord   le   milieu   physique   du   Niger,   puis   s’intéresse à quelques caractéristiques  des  animaux  de  l’étude  à  savoir  la  race  bovine  Azawak  et  la  race  caprine  dénommée   chèvre rousse de Maradi. En effet, le zébu Azawak est un animal de taille moyenne (1,3 m au garrot), Dans des très bonnes conditions et en élevage intensif, la vache zébu Azawak peut produire en moyenne  12  litres  par  jour.  Le  rendement  à  l’abattage  va  de  50  à  60%.  Quant  à  la  chèvre  rousse,  elle   est de taille moyenne ou petite (0,55-0,65 m). La durée de lactation est de 3 à 4 mois après la mise bas selon   les   conditions   d’élevage   et   la   production   laitière   annuelle   est   de   150   kg   en   200   jours.   Le   rendement  à  l’abattage  (poids  carcasse)  varie  de  50  à  55%  pour  le  sujet  castré. Le deuxième chapitre est une synthèse bibliographique sur la physiologie de la production et composition chimique du colostrum. Cette revue fait la compilation des informations les plus récentes sur le mécanisme de synthèse du colostrum, son aspect physico-chimique, son importance et enfin les facteurs de variation des composants chimiques de cette première sécrétion mammaire après la mise bas. Le colostrum renferme tous les éléments nécessaires permettant non seulement une protection contre les agressions d ́agents pathogènes, mais également une croissance rapide des jeunes animaux. Le chapitre trois est relatif à la comparaison par méta-analyse de la composition chimique du colostrum de la race bovine Azawak à des données synthétisées de la littérature. Cette étude a guidé le choix  de  l’espèce  dont  le  colostrum  doit  être administré au cours des expériences sur le terrain. Les concentrations  moyennes  d’IgG, IgM, MS, protéines et matières grasses pour la vache Azawak ont présenté des  valeurs  plus  faibles  (P  ˂  0,001) que celles obtenus chez d'autres races, mais il convient de noter des niveaux élevés d'IgA (P > 0,05), de  lactose  et  de  cendre  brute  (P  ˂  0,001). En ce qui concerne les minéraux solubles, les concentrations moyennes de Ca, P, Na et Mg dans le colostrum de bovin Azawak étaient  significativement  plus  élevées  (P  ˂  0,001) que celles de moyennes obtenues à partir des données de synthèse. En conclusion, comparé aux données de littérature, le colostrum de vache Azawak semble être plus pauvre en immunoglobuline, en lipides et en protéines, mais plus riche en lactose et en minéraux.  Il  se  pourrait  qu’il  s’agisse  d’une  adaptation  de  la  race  au  milieu  sahélien. Le  chapitre  quatre  est  intitulé  "l'Effet  de  l’administration  du  colostrum  de  bovin  Azawak  sur  le  profil   plasmatique, la croissance et la survie chez les chevreaux roux". Cette  étude  visait  à  évaluer  l’impact   de  l’administration  de  colostrum  hétérologue  Azawak  sur  le  profil  protéique  plasmatique,  la  croissance   et le taux de survie des chevreaux roux au Niger. Après la naissance et ce, jusqu'à la fin de l'essai, les poids vifs ont augmenté avec le temps dans les deux groupes, mais les valeurs ont été plus élevées dans le groupe colostrum que dans le groupe témoin (+ 1,4 kg à j29, P < 0,001). Dans l'ensemble, le groupe colostrum a présenté un gain moyen quotidien largement supérieur à celui du groupe témoin (P < 0,001). Les concentrations moyennes de fractions plasmatiques obtenues à l'âge de 10 et 30 jours ont atteint des valeurs plus élevées dans le lot colostrum que dans le lot contrôle. A 10 jours, le groupe colostrum a tendu à montrer des teneurs supérieures pour l'ɑ-globuline  et  la  β1-globuline (P < 0,06). A 30   jours,   les   protéines   totales   et   les   β2-globulines ont été supérieures dans le groupe colostrum. L’administration  du  colostrum  hétérologue  chez  le  chevreau  semble donc avoir des effets positifs sur certains paramètres plasmatiques et même les performances pondérales. Le  cinquième  chapitre  traite  de  "Effet  de  l’apport  en  colostrum  de  bovin  Azawak  sur  les  performances,   les paramètres de reproduction et la survie chez les chevreaux roux". Cette étude a permis de comparer les performances de croissance pondérale ainsi que le gain moyen quotidien de deux lots de cabris élevés selon les deux modes c'est-à-dire la supplémentation (n = 20) et son absence non (n = 20). Le poids vif moyen du groupe colostrum a atteint une valeur significativement plus élevée que celle obtenu chez les animaux non supplémenté (P < 0,001) et les effets du traitement sur ADG ont été observés jusqu'à 150 jours après la fin de la supplémentation. Une tendance similaire de longue durée a également été observée en relation avec le taux de mortalité (25% pour ColG vs 55% pour ConG, (P = 0,05). L'âge à la première mise bas tendait à être plus faible dans le groupe traité (13,8 ± 0,7 vs 14,1 ± 0,8 mois, p ˂ 0,1). Dans l'ensemble, l'analyse statistique a révélé des différences très significatives en faveur du groupe de colostrum. Globalement,   l’analyse   statistique   des   données   a   révélé   des   différences hautement significatives en faveur du lot colostrum. Le  sixième  chapitre  porte  sur  l’Effet  de  l’administration  post-partum de colostrum bovin Azawak sur les paramètres zootechniques de cabris roux. Un dispositif quasi-similaire à celui du premier essai (chapitre IV) a été appliqué. La différence se situait au niveau de la dose du colostrum administré. En effet, la quantité de colostrum administrée (15 ml) lors du premier essai a été majorée de 66,7 % au cours de cette expérimentation soit une quantité de 25ml/jour/chevreau. Comme le premier essai a été probant,   l’objectif   de   ce   travail   était   de   voir   si   l’augmentation   de   la   dose   du   colostrum   à   administrer   peut améliorer davantage les paramètres zootechniques et réduire considérablement le taux de mortalité. Les résultats indiquent que la supplémentation avec du colostrum bovin augmente la croissance  des  chevreaux  principalement  jusqu’au  sevrage  (P < 0,001),  améliore  l’état  sanitaire  et   diminue le taux de mortalité (P < 0,05), modifie quelques paramètres zootechniques. Cette étude suggère de prodiguer un allaitement  artificiel  chez  d’autres  espèces  animales  dont  les  mères  peinent  à   couvrir les besoins en colostrum et en lait de leur progéniture. A   notre   connaissance,   dans   l’environnement   étudié,   ce   travail   est   original et semble apporter de nouvelles connaissances qui auront probablement des applications pratiques dans les régions présentant  des  conditions  d’élevage  assez  difficiles. [less ▲]

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