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See detailContribution au diagnostic et à la correction des carences en iode et sélénium chez les bovins
Guyot, Hugues ULg

Doctoral thesis (2007)

Deficiencies of selenium (Se) and iodine (I) are widespread in livestock all over Europe. They have an impact on the animals’ health. Since the clinical signs of the deficiencies are rarely pathognomic ... [more ▼]

Deficiencies of selenium (Se) and iodine (I) are widespread in livestock all over Europe. They have an impact on the animals’ health. Since the clinical signs of the deficiencies are rarely pathognomic, auxiliary exams, based on blood and milk samples are needed for the confirmation of the diagnosis. To evaluate the Se and I status, the plasmatic Se content, the erythrocytic glutathione peroxydase activity (GPX), and the inorganic plasmatic I (IIP) content are measured routinely. Other analyses, like e.g. the dosage of tri-iodothyronine (T3) or thyrotropine (bTSH) can be used. Once the deficiency is diagnosed, it can be corrected by several methods. The first aim of the study was to evaluate the zinc, copper, Se, and I status of Wallonian dairy and beef herds and to correlate their trace element status to their health. The trace element status of the herds with pathologies was less good than that of healthy herds. Further, more herds with pathologies had deficiencies when compared to healthy ones. Dairy herds had a better trace element status than beef herds. Se and I deficiencies are among the most important ones and have the most severe sequels. Therefore, the subsequent parts of the study focussed on these two trace elements. The second aim was the establishment of a technique for the dosage of bTSH and of reference values in healthy cattle. Reference ranges for bTSH and for thyroxine (T4) have been determined in healthy adult cows and in healthy calves. Thereafter, the next aim was to compare the concentration of bTSH in newborn calves with goitre to those obtained in healthy calves, in order to validate a diagnostic test for this pathology. The bTSH allowed the discrimination of the two groups and to approve the diagnosis of hypothyroidism in some of the calves. The threshold value of bTSH for the diagnosis of hypothyroidism in the newborn calf has been fixed at 35 µU/ml. The fourth aim was to compare the I (IIP) and Se (plasmatic Se, GPX) status as well as the thyroid status (bTSH, T4, T3, rT3) in dried pregnant cows and their calves and in non-pregnant cows, that received normal diet and a diet enriched in Se and I. In those receiving a Se and I enriched diet, the T4 and the bTSH decreased while the IIP, the T3, and the GPX activity increased. In the group that received a diet with normal Se and I contents, only the GPX activity increased. At birth, calves from mothers receiving the Se and I enriched diet, had a higher IPP content and GPX activity, and a lower bTSH concentration than calves from the other group. The last aim was to compare the effects of two different forms of Se (sodium selenite versus seleno-methionine) and two different doses of Se (0.1 versus 0.5 ppm) on the health and the Se status of Se deficient Belgian Blue cows and their calves. The first two groups of cows received a ration with 0.1 and 0.5 ppm, respectively, of Se in the form of sodium selenite (Na-Se 0.1 and Na-Se 0.5), while the third group received 0.5 ppm of Se in the form of seleno-methionine (Y-Se 0.5). The Se content of plasma, colostrum, and milk was higher in the cows of group Y-Se 0.5 when compared to the two other groups. The Se content of the plasma was higher in calves from group Y-Se 0.5 when compared to the two other groups. The daily weight gain of the Y-Se 0.5 group was higher than those of the group Na-Se 0.1. The incidence of diarrhoea among calves in group Na-Se 0.1 was higher than in group Y-Se 0.5. In conclusion, trace elements deficiencies are common in Wallonia and often they are multiple. They play a major role in the aetiology of multifactorial diseases diagnosed in the cattle herds. Deficiencies in Se and in I are most commonly implicated in clinical problems. The diagnosis of these deficiencies is determined by blood analyses. Therefore, the tests need to be differentiated according to their capacity to test the nutritional or the thyroid status. A simultaneous supplementation with I and Se, as well as the form of the supplemented Se, may modify the interpretation of the nutritional and the thyroid status. Better reproduction performances and a better health have been observed in herds with a normal trace element status. Furthermore, the advantage of the supplementation with Se in the form of seleno-methionine has been demonstrated in comparison to sodium selenite in deficient Belgian Blue cattle. This study opened numerous perspectives. The measurement of bTSH should be implemented in laboratories in order to offer it as a routine analysis to the practitioning veterinarian, who could use this tool in the framework of many diseases other than goitre. From a fundamental point of view, the dosage of deiodinases would allow the understanding of the regulation and of the synthesis of the thyroid hormones in bovines, and identifying the role of Se and I in this process. Finally, following the discoveries concerning the seleno-methionine, the effect of organic forms of other trace elements in bovine supplementation should be investigated. [less ▲]

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See detailClinical differentiation of malignant catarrhal fever, mucosal disease and bluetongue.
Bexiga, R.; Guyot, Hugues ULg; Saegerman, Claude ULg et al

in Veterinary Record : Journal of the British Veterinary Association (2007), 161(25), 858-9

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See detailDescription clinique des cas de FCO survenus au Nord de l'Europe durant l'été et l'automne 2006
Guyot, Hugues ULg; Mauroy, Axel ULg; Thiry, Etienne ULg et al

in Bulletin des Groupements Techniques Vétérinaires (2007), 39(avril), 89-96

La fièvre catarrhale ovine (FCO) a été identifiée au Nord de l’Europe <br />le 14 août 2006. L’Allemagne, la Belgique, les Pays-Bas et, dans une <br />moindre mesure, le Grand-Duché de Luxembourg et la ... [more ▼]

La fièvre catarrhale ovine (FCO) a été identifiée au Nord de l’Europe <br />le 14 août 2006. L’Allemagne, la Belgique, les Pays-Bas et, dans une <br />moindre mesure, le Grand-Duché de Luxembourg et la France ont été <br />affectés. Le sérotype 8 du virus de la FCO (exotique) a rapidement été <br />identifié ainsi qu’un vecteur, Culicoides dewulfi, une espèce indigène du <br />Nord de l’Europe. La maladie s’est rapidement développée et au 1er <br />février 2007, on recensait 2137 foyers de FCO, toutes espèces de <br />ruminants confondues. Globalement, la maladie a affecté davantage les <br />bovins (54 %) que les ovins (46 %). Les signes cliniques les plus <br />fréquemment observés chez les bovins étaient des lésions sur le museau <br />et la cavité buccale (ulcérations/croûtes), de la salivation et des boiteries <br />chez des animaux adultes. La morbidité et la mortalité animales étaient <br />respectivement de maximum 5 % et 1 %. Les principaux signes cliniques <br />rencontrés chez le mouton étaient également des lésions sur le museau <br />et la cavité buccale (ulcérations/croûtes), de l’amaigrissement et des <br />boiteries. La morbidité et la mortalité animales étaient respectivement <br />de maximum 12 % et 6 %. Les signes cliniques n’étant pas <br />pathognomoniques et le diagnostic différentiel relativement vaste, seul <br />un examen de laboratoire permet d’établir un diagnostic de certitude. [less ▲]

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See detailThyrotropin in newborn calves as a tool for diagnosing hypothyroidism
Guyot, Hugues ULg; Lebreton, Pascal; Alves de Oliveira, Laurent et al

in Cattle Practice (2007), 15(Part 3), 271-275

The hypothalamic-pituitary-thyroid axis is of particular importance for the adaptation of mammals to their environment. Hypothyroidism is the most common type of thyroid disorders in cattle. Thyrotropin ... [more ▼]

The hypothalamic-pituitary-thyroid axis is of particular importance for the adaptation of mammals to their environment. Hypothyroidism is the most common type of thyroid disorders in cattle. Thyrotropin (TSH) is used in several mammalian species for the diagnosis of primary hypothyroidism. Currently in cattle, thyroid hormone assays are used to diagnose such disease. The aim of the study was to compare different tools for diagnosing hypothyroidism in newborn calves. Twelve goitrous newborn calves from two beef herds were studied as well as 45 healthy newborn calves. Bovine TSH, thyroxine (T4), tri-iodothyronine (T3), reverse-T3 (rT3), plasmatic inorganic iodine (PII) and glutathione peroxidase in erythrocytes (GPXe) were assayed in these calves during the first day of life. T4/T3 and T4/TSH ratio were calculated. Furthermore, TSH, T4, PII and GPXe were also assayed in their dams at calving. Results were analysed using Wilcoxon rank sum test and Spearman's rank correlation coefficient. A significant higher value (P < 0.01) of TSH was seen for the group of goitrous calves compared to healthy calves. There was no difference between healthy and goitrous calves for GPXe (P > 0.1) and PII (P > 0.05). Significantly higher values were seen for healthy calves compared to goitrous calves concerning T4, T4/T3 ratio, T4/TSH ratio, rT3 (P < 0.0 1) and T3 (P < 0.05). Regarding the group of goitrous calves, those that had larger goitre at palpation and were hairless (n=8) died within the first day of life while the four other with moderate goitre and normal hair stayed alive. Goitrous-dead calves had higher TSH values than goitrous-alive ones (P < 0.01), lower T4, T3, T4/TSH (P < 0.0 1) and rT3 (P < 0.05) but similar T4/T3 ratio (P > 0.1). Furthermore, it appeared that T4 and rT3 values in goitrous-alive calves were not different compared to healthy calves (P > 0.1). Regarding TSH (rho=0.44), T4 (rho=-0.44), PII (rho=0.70) and GPXe (rho=0.87), there was a correlation between healthy calves and their dams, with significantly higher values being found in the calves (P < 0.01). There was no correlation between values of TSH and T4 in goitrous calves and their dams (P > 0.1). However, for these animals there was a strong relationship in the values of PH (rho=0.82) and GPXe (rho=0.94) (P < 0.01). TSH, PII and GPXe were significantly higher in goitrous calves compared to their dams (P < 0.01). Regarding T4, only goitrous-dead calves showed significantly lower values than their dams (P < 0.01). Dams with goitrous calves had higher TSH (P < 0.01) and PII (P < 0.05) compared to dams with healthy calves but similar T4 and GPXe (P > 0.1). This study revealed that TSH alone is a good marker for hypothyroidism in newborn calves. In the absence of TSH assay, the T4/T3 ratio may be used to diagnose hypothyroidism in newborn calves. In our study, although T4/T3 ratio was helpful in identifying goitrous calves, it did not allow to discriminate goitrous-dead from goitrous-alive calves, contrary to TSH. In our study, the presence of a goitre in newborn calves could not be explained by the iodine (PII) and thyroid (via T4) status of their dams. [less ▲]

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See detailComparative responses to sodium selenite and organic selenium supplements in Belgian Blue cows and calves
Guyot, Hugues ULg; Spring, P.; Andrieu, S. et al

in Livestock Science (2007), 111(3), 259-263

Belgian Blue (BB) beef cattle is particularly prone to selenium (Se) deficiency due to the poor Se content of soil and roughages on rearing farms and the higher requirements of this hypermuscled breed ... [more ▼]

Belgian Blue (BB) beef cattle is particularly prone to selenium (Se) deficiency due to the poor Se content of soil and roughages on rearing farms and the higher requirements of this hypermuscled breed. The goal of this trial was to compare the effects of different forms and concentrations of Se supplementation on Se status, health and performance in 60 pregnant Se-deficient BB cows. Cows were allocated to 3 experimental groups receiving selenized-yeast at 0.5 ppm Se on total ration (Y-Se 0.5), Na-selenite at 0.5 ppm Se on total ration (Na-Se 0.5) and Na-selenite at 0.1 ppm Se on total ration (Na-Se 0.1), respectively. Cows were supplemented from 2 months before calving until 2 months after calving. Data on performance, health and Se status of the dams and their calves were analyzed using a linear model, least squares means and logistic regression. At the end of the study, plasmatic Se (pSe) was significantly higher (P<0.01) in cows receiving Y-Se than in cows from other groups. Glutathion-peroxidase in erythrocytes (GSH-pxe) was higher in Y-Se and Na-Se 0.5 than Na-Se 0.1 group (P<0.01). Se content in colostrum and milk was significantly higher (P< 0.01) in Y-Se than other groups. At birth, Se status of calves from group Y-Se was significantly higher than those of other groups (P<0.01). Plasmatic Se in calves remained higher for 75 days after birth in Y-Se compared to other groups (P<0.01). Diarrhoea was the most commonly observed disease in the calves and, during the first 15 days of life, diarrhoea occurred in 6%, 21% and 35% of calves from groups Y-Se, Na-Se 0.5 and Na-Se 0.1, respectively. Over the whole 75 days trial period, incidence of diarrhoea was 19, 29 and 65%, respectively. Average daily gain (ADG) in calves born from Y-Se group of cows tended to be higher than in Na-Se 0.5 (P=0.06) and Na-Se 0.1 (P<0.05) but there was no difference between Na-Se 0.5 and Na-Se 0.1 (P>0.1). At the same dosage, Y-Se conferred better Se status in both dams and their calves than did Na-Se. Requirement of 0.1 ppm Se seems to be insufficient in BB to optimise health and performance. Regarding health status and ADG in calves, Y-Se seems also to result in better performance. (C) 2007 Elsevier B.V. All rights reserved. [less ▲]

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See detailLe diagnostic des carences en Iode et Sélénium chez les bovins
Guyot, Hugues ULg; Rollin, Frédéric ULg

in Annales de Médecine Vétérinaire (2007), 151

Selenium and iodine deficiencies are frequently present in cattle in Europe with a negative impact on animal health, reproduction and production. Deficiencies in animals also influence human health owing ... [more ▼]

Selenium and iodine deficiencies are frequently present in cattle in Europe with a negative impact on animal health, reproduction and production. Deficiencies in animals also influence human health owing to consumption of their products. These deficiencies must be correctly diagnosed in order to avoid lack of diagnosis or wrong diagnosis. Since there are many interactions between nutrients, a nutritional approach only is of limited interest. Therefore, the diagnosis based on samples obtained on the animals is more reliable. Clinical signs of selenium and iodine deficiencies are rarely pathognomonic. Laboratory analyses are thus necessary to confirm the diagnosis. The present review relates the principal clinical signs of selenium and iodine deficiencies and the confirmation of the deficiency by the measurements of different nutritional and functional markers available for cattle, either on blood, milk, urine or tissues. Finally, a protocol for the diagnosis of selenium and iodine deficiencies is proposed [less ▲]

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See detailRespiratory distress syndrome in full-term newborn calves
Rollin, Frédéric ULg; Danlois, Fabien; Aliaoui, Hamani et al

Conference (2007)

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See detailFièvre Catarrhale Ovine chez les ruminants. Description clinique des cas vécus dans le Nord de l’Europe durant l’été-automne 2006
Guyot, Hugues ULg; Mauroy, Axel ULg; Thiry, Etienne ULg et al

in Bulletin des GTV (2007)

La fièvre catarrhale ovine (FCO) a été identifiée au Nord de l’Europe le 14 août 2006. L’Allemagne, la Belgique, les Pays-Bas et, dans une moindre mesure, le Grand-Duché de Luxembourg et la France ont été ... [more ▼]

La fièvre catarrhale ovine (FCO) a été identifiée au Nord de l’Europe le 14 août 2006. L’Allemagne, la Belgique, les Pays-Bas et, dans une moindre mesure, le Grand-Duché de Luxembourg et la France ont été affectés. Le sérotype 8 du virus de la FCO (exotique) a rapidement été identifié ainsi qu’un vecteur, Culicoides dewulfi, une espèce indigène du Nord de l’Europe. La maladie s’est rapidement développée et au 1er février 2007, on recensait 2137 foyers de FCO, toutes espèces de ruminants confondues. Globalement, la maladie a affecté davantage les bovins (54 %) que les ovins (46 %). Les signes cliniques le plus fréquemment observés chez les bovins étaient des lésions sur le museau et la cavité buccale (ulcérations/croûtes), de la salivation et des boiteries chez des animaux adultes. La morbidité et la mortalité animales étaient respectivement de maximum 5 % et 1 %. Les principaux signes cliniques rencontrés chez le mouton étaient également des lésions sur le museau et la cavité buccale (ulcérations/croûtes), de l’amaigrissement et des boiteries. La morbidité et la mortalité animales étaient respectivement de maximum 12 % et 6 %. Les signes cliniques n’étant pas pathognomoniques et le diagnostic différentiel relativement vaste, seul un examen de laboratoire permet de poser un diagnostic de certitude. [less ▲]

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See detailCongenital muscular dystonia (CMD): a new congenital pathology in Belgian Blue calves
Vandeputte, Sébastien ULg; Brihoum, Mounir ULg; Hubin, Xavier et al

Conference (2006, October 15)

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See detailFully automated heart rate variability assessment in dairy cows
Janda, Jozef; Guyot, Hugues ULg; Sandersen, Charlotte ULg et al

in Acta Physiologica (2006, May), 187(Suppl 651), -16

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See detailCombined spastic paresis of both gastrocnemius and femoral quadriceps muscles in Belgian blue calves
Janda, Jozef; Uyttenhoef, Aude; Vandeputte, Sébastien ULg et al

Conference (2006)

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See detailBluetongue in northern Europe.
Thiry, Etienne ULg; Saegerman, Claude ULg; Guyot, Hugues ULg et al

in Veterinary Record : Journal of the British Veterinary Association (2006), 159(10), 327

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See detailComparative responses to sodium selenite and Sel-Plex® organic selenium supplements in Belgian Blue cows and calves
Guyot, Hugues ULg; Rollin, Frédéric ULg; Andrieu, Sylvie et al

in Nutritional Biotechnology in the Feed and Food Industries (Alltech’s 22nd Annual Symposium) (2006)

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See detailTools to assess iodine deficiency in calves born from deficient and non deficient dams
Guyot, Hugues ULg; Uyttenhoef, Aude; Lebreton, Pascal et al

Poster (2006)

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See detailRelationship between haptoglobin, serum amyloid A, and clinical status in a survey of dairy herds during a 6-month period
Humblet, Marie-France ULg; Guyot, Hugues ULg; Boudry, Benjamin et al

in Veterinary Clinical Pathology (2006), 35(2), 188-193

Haptoglobin and serum amyloid A are major acute phase proteins in cattle. Dairy cattle often develop pathologic conditions in the peripartum period; acute phase proteins may be useful in their diagnosis ... [more ▼]

Haptoglobin and serum amyloid A are major acute phase proteins in cattle. Dairy cattle often develop pathologic conditions in the peripartum period; acute phase proteins may be useful in their diagnosis. Objectives: The purpose of this study was to compare the accuracy of serum haptoglobin (Hp) and serum amyloid A (SAA) concentrations with clinical health status for diagnosing disease during the peripartum period in dairy cattle. Methods: Dairy cows from 4 herds were evaluated every 15 days over a 6-month period. Health status was determined by thorough clinical examination. Haptoglobin and SAA concentrations were measured in serum using validated methods and the results were classifed as positive or negative based on defined cutoff points. Disease prevalence, sensitivity, and specificity were compared using clinical examination as the gold standard. Results: A total of 1896 samples from 158 cows were analyzed. Significant increases in mean Hp and SAA concentrations were observed in the week following parturition in both primiparous and multiparous cows, although high interindividual variability was observed. Both Hp and SAA had low sensitivity but higher specificity in determining disease status compared with clinical examination. Increased concentrations of Hp and SAAwere found in ,10% of samples from clinically healthy cows, except in the week after parturition. Conclusions: Haptoglobin and serum amyloid A should be used with caution as markers of inflammation in the week after calving. Poor sensitivity in other postpartum periods could be related to the higher incidence of chronic (vs acute) inflammation. Haptoglobin may be appropriate for routine screening, but further work needs to be done to assess its value as an indicator of herd health. [less ▲]

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