Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present work had as its objective to assess the oxidizing metabolism of neutrophils, the complete blood count (CBC) and the oxidizing profile of experimentally infected lambs with Haemonchus contortus and supplemented with selenium and vitamin E. 20 male lambs were used, of the Corriedale breed, distributed in four experimental groups with 5 animals: G1 larvae infected animals and supplemented with 0.2mg/kg living weight (PV) of selenite via intramuscular (IM); G2 larvae infected animals and supplemented with 0.2mg/kg PV of selenite IM and 2000 UI per animal of vitamin E IM; G3 larvae infected animals and supplemented with 2000 UI per animal of E IM; G4 larvae infected animals. For the CBC and the biochemical analysis blood collection on the day zero (T0) were carried out, 20 (T1), 40 (T2) and 60 (T3) through jugular venipuncture using vacutainer® tubes. The weighing and the egg determination by gram of animal feces occurred in the same experimental times. For the NBT tests heparinized blood samples were collected in the days zero, 30, 60. Smaller leukocyte values were detected in the supplemented group exclusively with selenium (G1) in relation to the control group (G4) in time 4. Concerning the lymphocytes it was observed a decrease in the G1 in relation to the supplemented only with vitamin E (G3) and G4 in time 3 (T3). For both the tests, NBT-NE and NBT-E there was a decrease in the dye reduction capacity at 60 days in relation to the other times in the groups treated with selenium (G1 and G2). The result of the oxidizing profile showed a significant elevation in the GSH-Px enzyme in the supplemented groups with selenium. Still, the correlation of Pearson revealed the existence of a negative correlation between the concentrations of GSH-Px and TBARS and between this enzyme and the OPG values. Increments were also observed for the catalase enzyme in animal which received the selenium supplementation or when this element was associated to the vitamin E. Smaller values of lipid peroxidation (TBARS) were detected in supplemented animals when these were compared to the control group. These results suggest that the reduced reserves of this antioxidant may exacerbate the generation of free radicals with an increase of the lipid peroxidation and the increase of the environment contamination by the eggs of Haemonchus contortus. Facing these results it is possible to conclude that the selenium supplementation provides a larger protection to the cell antioxidant and to the organism as a whole in lambs experimentally infected by Haemonchus contortus. / O presente trabalho teve como objetivo avaliar o metabolismo oxidativo dos neutrófilos, o hemograma e o perfil oxidativo de cordeiros experimentalmente infectados com Haemonchus contortus e suplementados com selênio e vitamina E. Foram utilizados 20 cordeiros machos, da raça Corriedale, distribuídos em quatro grupos experimentais com 5 animais: G1- animais infectados com larvas e suplementados com 0,2mg/kg de peso vivo (PV) de selenito de sódio por via intramuscular (IM); G2- animais infectados com larvas e suplementados com 0,2mg/kg PV de selenito de sódio IM e 2000 UI por animal de Vitamina E IM; G3- animais infectados com larvas e suplementados com 2000 UI por animal de Vitamina E IM; G4-animais infectados com larvas. Todos os grupos foram infectados, pela via oral, com 500 larvas L3 de Haemonchus contortus por animal a cada dois dias, pelo período de vinte dias a partir do dia zero. Para o hemograma e as análises bioquímicas foram realizadas coletas de sangue nos dias zero (T0), 20 (T1), 40 (T2) e 60 (T3) por venopunção da jugular utilizando-se tubos vacutainer®. As pesagens e a determinação dos ovos por grama de fezes dos animais ocorreram nesses mesmos tempos experimentais. Para as provas de NBT foram coletadas amostras de sangue heparinizadas nos dias zero, 30 e 60. Menores valores de leucócitos totais foram detectados no grupo suplementado exclusivamente com selênio (G1) em relação ao grupo controle (G4) no tempo 4. Em relação aos linfócitos observou-se diminuição no G1 em relação ao suplementado somente com vitamina E (G3) e G4 no tempo 3 (T3). Para ambos os testes, NBT-NE e NBT-E houve uma diminuição da capacidade de redução do corante aos 60 dias em relação aos demais tempos nos grupos tratados com selênio (G1 e G2).Os resultados do perfil oxidativo demonstraram significativa elevação da atividade da enzima GSH-Px nos grupos suplementados com selênio. Ainda, a correlação de Pearson revelou a existência de correlação negativa entre as concentrações de GSH-Px e TBARS e entre esta enzima e os valores de OPG. Incrementos também foram observados para a enzima catalase nos animais que receberam suplementação com selênio ou quando este elemento foi associado a vitamina E. Menores valores de lipoperoxidação lipídica (TBARS) foram detectados nos animais suplementados quando estes foram comparados ao grupo controle. Esses resultados sugerem que as reservas diminutas deste antioxidante podem exacerbar a geração de radicais livres com um aumento da peroxidação lipídica e o aumento da contaminação ambiental pelos ovos de Haemonchus contortus. Diante dos resultados é possível concluir que a suplementação com selênio proporciona uma maior proteção antioxidante celular e ao organismo como um todo de cordeiros experimentalmente infectados pelo Haemonchus contortus.

Résumé L’objectif de cette étude était de déterminer les effets de la source de sélénium sur les concentrations de Se et de GSH-Px des vaches de boucherie (n =33) et leurs veaux et sur des paramètres immunitaires des veaux. Deux groupes de vaches ont reçu 3 mg/j/animal de Se organique ou inorganique dans le minéral. Le troisième groupe n'a pas été supplémenté en Se et leurs veaux ont été divisés en deux sous-groupes, l’un des deux a reçu une injection de sélénite de sodium (0,087 mg/Kg) à la naissance. Le Se et la GSH-Px ont été respectivement mesurés par HPLC-UV et par cinétique enzymatique. La phagocytose, la flambée respiratoire et le ratio CD4:CD8ont été évalués par des kits commerciaux et les IgG totales ont été mesurés par immunodiffusion radiale. La supplémentation de Se a augmenté significativement le Se sérique et colostral (P<0,02) et la GSH-Px(P≤0,04) pour les vaches et leurs veaux avec un effet significativement plus élevé pour le Se organique. Le Se du lait a augmenté de façon significative uniquement avec la source organique du Se (P≤0,0007). L’injection du Se chez les veaux a permis une augmentation significative mais temporaire (P<0,0001) du Se sérique. La supplémentation en Se n’a pas influencé les paramètres immunitaires mesurés (P>0,01, non significatif après correction de Bonferroni). Nous concluons que la supplémentation en Se améliore le niveau du Se colostral, lacté et sérique ainsi que la GSH-Px pour les vaches et leurs veaux sans effet sur les paramètres immunitaires mesurés des veaux. Mots clés: Sélénium, veaux de boucherie, phagocytose, flambée respiratoire, anticorps, ratio CD4:CD8, GSH-Px. / Abstract The aims of this study were to determine the effects of selenium (Se) supplementation sources (organic and inorganic) on Se and GSH-Px concentrations of beef cows (n=33) and their calves and on immune parameters of the calves. Two groups of cows were given daily 3 mg of either organic or inorganic Se in mineral supplement starting from 12 weeks before calving until weaning. The third group had no Se added into the diet and their calves were divided into two subgroups either injected or not with 0.087 mg/kg of sodium selenite after birth. Serum Se and whole blood GSH-Px were respectively measured by HPLC-UV and by kinetic-enzymatic technique. Calves immune parameters were evaluated using commercial kits for phagocytosis, respiratory burst and CD4:CD8 ratio and radial immunodiffusion for total IgG concentrations. In cows and calves, Se supplementation increased significantly serum and colostrum Se concentrations (P<.02) with significant higher effect for organic source. However, milk Se concentrations increased significantly only with the organic source (P≤.0007). Se supplementation increased GSH-Px concentrations in cows (P≤.04) and their calves (P≤.0004); organic source induced a higher effect than inorganic one in calves (P≤.0004). Se injection in calves allowed a temporary increase (P<.0001) of serum Se concentrations. No significant differences were noticed throughout the experiment for all of the immune parameters measured (P>.01, not significant after Bonferroni adjustment). Our results showed that Se supplementation improved colostrum, milk and serum Se and GSH-Px concentrations in cows and their calves without effect on the measured immune parameters in calves. Key words: selenium, beef calves, phagocytosis, respiratory burst, antibodies, CD4:CD8 ratio, GSH-Px.

Résumé L’objectif de cette étude était de déterminer les effets de la source de sélénium sur les concentrations de Se et de GSH-Px des vaches de boucherie (n =33) et leurs veaux et sur des paramètres immunitaires des veaux. Deux groupes de vaches ont reçu 3 mg/j/animal de Se organique ou inorganique dans le minéral. Le troisième groupe n'a pas été supplémenté en Se et leurs veaux ont été divisés en deux sous-groupes, l’un des deux a reçu une injection de sélénite de sodium (0,087 mg/Kg) à la naissance. Le Se et la GSH-Px ont été respectivement mesurés par HPLC-UV et par cinétique enzymatique. La phagocytose, la flambée respiratoire et le ratio CD4:CD8ont été évalués par des kits commerciaux et les IgG totales ont été mesurés par immunodiffusion radiale. La supplémentation de Se a augmenté significativement le Se sérique et colostral (P<0,02) et la GSH-Px(P≤0,04) pour les vaches et leurs veaux avec un effet significativement plus élevé pour le Se organique. Le Se du lait a augmenté de façon significative uniquement avec la source organique du Se (P≤0,0007). L’injection du Se chez les veaux a permis une augmentation significative mais temporaire (P<0,0001) du Se sérique. La supplémentation en Se n’a pas influencé les paramètres immunitaires mesurés (P>0,01, non significatif après correction de Bonferroni). Nous concluons que la supplémentation en Se améliore le niveau du Se colostral, lacté et sérique ainsi que la GSH-Px pour les vaches et leurs veaux sans effet sur les paramètres immunitaires mesurés des veaux. Mots clés: Sélénium, veaux de boucherie, phagocytose, flambée respiratoire, anticorps, ratio CD4:CD8, GSH-Px. / Abstract The aims of this study were to determine the effects of selenium (Se) supplementation sources (organic and inorganic) on Se and GSH-Px concentrations of beef cows (n=33) and their calves and on immune parameters of the calves. Two groups of cows were given daily 3 mg of either organic or inorganic Se in mineral supplement starting from 12 weeks before calving until weaning. The third group had no Se added into the diet and their calves were divided into two subgroups either injected or not with 0.087 mg/kg of sodium selenite after birth. Serum Se and whole blood GSH-Px were respectively measured by HPLC-UV and by kinetic-enzymatic technique. Calves immune parameters were evaluated using commercial kits for phagocytosis, respiratory burst and CD4:CD8 ratio and radial immunodiffusion for total IgG concentrations. In cows and calves, Se supplementation increased significantly serum and colostrum Se concentrations (P<.02) with significant higher effect for organic source. However, milk Se concentrations increased significantly only with the organic source (P≤.0007). Se supplementation increased GSH-Px concentrations in cows (P≤.04) and their calves (P≤.0004); organic source induced a higher effect than inorganic one in calves (P≤.0004). Se injection in calves allowed a temporary increase (P<.0001) of serum Se concentrations. No significant differences were noticed throughout the experiment for all of the immune parameters measured (P>.01, not significant after Bonferroni adjustment). Our results showed that Se supplementation improved colostrum, milk and serum Se and GSH-Px concentrations in cows and their calves without effect on the measured immune parameters in calves. Key words: selenium, beef calves, phagocytosis, respiratory burst, antibodies, CD4:CD8 ratio, GSH-Px.

Soils in many regions in North America, including Quebec, are selenium (Se) deficient. To date, no field study has been conducted in Quebec regarding the Se status of horses. The objectives of this study were (1) to measure plasma Se in horses from different geographical locations in the province of Quebec and (2) to survey the Se consumption of the sampled horses. Four samplings were done on 59 horses over a 1-year period. Plasma was analyzed for Se, vitamin E and GSH-Px. Hay, concentrate and water were also analyzed for Se. Horses were classified in four groups for statistical analysis according to their forage:concentrate consumption respectively: group 1- 100% : 0%; group 2- 75-99% : 1-24%; group 3- 51-74% : 25-49%; group 4- < 50% : ≥ 50%. Owners were asked questions from a survey questionnaire at each visit. Results demonstrate that plasma Se varies according to BCS (P = 0.031) (n = 224 measures, 1 measure/horse/season), the season (P = 0.015) and the feeding group (P< 0.001). Plasma vitamin E was affected by the sex (P = 0.047) (mares: n = 37, geldings: n = 18, stallions: n = 4), the exercise level (P< 0.001) and the season (P< 0.001). GSH-Px activity was influenced by the type of feeding only (P = 0.002). When comparing plasma Se, vitamin E and GSH-Px results along with the answers of the survey questionnaire, it is possible to conclude that feeding practices of horse owners in Quebec are not appropriate to meet the Se requirements of horses. / Les sols de plusieurs régions en Amérique du Nord, incluant le Québec, sont déficients en sélénium (Se). À ce jour, aucune étude sur le terrain n’a été menée au Québec en ce qui concerne le statut en Se des chevaux. Les objectifs de cette étude étaient (1) de mesurer le Se sanguin chez des chevaux de différentes régions du Québec et (2) de recenser la consommation de Se des chevaux échantillonnés. Quatre échantillonnages ont été réalisés sur 59 chevaux durant une période d’un an. Le plasma a été analysé pour les éléments suivants : le Se, la vitamine E (interagit avec le Se en tant qu’antioxydant) et la glutathion peroxydase (GSH-Px). Le foin, les concentrés et l’eau consommés pas les chevaux ont aussi été analysés pour le Se. Les chevaux étaient classés en quatre groupes en raison de leur consommation de fourrages:concentré respectivement : groupe 1 - 100% : 0%; groupe 2- 75-99% : 1-24%; groupe 3- 51-74% : 25-49%; groupe 4- < 50% : ≥ 50%. Les propriétaires ont été sondés à chaque visite en utilisant un questionnaire validé. Les résultats démontrent que le niveau de Se plasmatique varie en fonction de l’état de chair (P = 0.031) (n = 224 mesures, 1 mesure/cheval/saison), de la saison (P = 0.015) et du groupe alimentaire (P< 0.001). La vitamine E plasmatique était influencée par le sexe (P = 0.047) (juments : n = 73, hongres : n = 18, étalons : n = 4), le niveau d’exercice (P< 0.001), et par la saison (P< 0.001). L’activité de la GSH-Px variait en fonction du groupe alimentaire (P = 0.002). À partir des résultats sanguins et des réponses au questionnaire, il est possible de conclure que les pratiques alimentaires des propriétaires de chevaux du Québec ne sont pas appropriées afin de répondre aux besoins en Se des chevaux.