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Patologia de neonatos bovinos originados por meio da técnica de transferência nuclear de células somáticas: clonagem | Pathology of bovine neonates generated by somatic cell nuclear transfer: Cloning 全文
2010
Santos, Caio Rodrigues dos | Grandi, Fabrizio | Miglino, Maria Angélica | Meirelles, Flávio Vieira | Maiorka, Paulo César
Patologia de neonatos bovinos originados por meio da técnica de transferência nuclear de células somáticas: clonagem | Pathology of bovine neonates generated by somatic cell nuclear transfer: Cloning 全文
2010
Santos, Caio Rodrigues dos | Grandi, Fabrizio | Miglino, Maria Angélica | Meirelles, Flávio Vieira | Maiorka, Paulo César
Os mecanismos de morte em animais clonados a partir de células somáticas são poucos elucidados. Malformações de órgãos, alterações de tamanho e peso desses animais foram anomalias já descritas, porém em casos isolados. Desse modo, estudos nos níveis anatomo e histopatológicos são de suma importância para ajudar a compreensão dos fatores responsáveis pelos altos índices de insucessos com a utilização da TNCS (transferência nuclear de células somáticas). Assim, o presente trabalho foi realizado com o objetivo de descrever, por meio de exames anatomopatológicos, as alterações presentes em um grupo de animais gerados por TNCS, que vieram a óbito entre 1 e 19 dias de vida. Esse experimento foi realizado entre os anos de 2004 e 2008 na fazenda Tambaú, cidade de Tambaú, Estado de São Paulo. No total foram gerados 21 animais da raça Nelore (Bos indicus), sendo que 11 vieram a óbito e dez apresentaram boa evolução clínica no período perinatal. Foram realizadas as necropsias dos animais e posterior análise histopatológica de tecidos alterados. Esse estudo mostrou alta prevalência de alterações cardiopulmonares, que provavelmente foram determinantes nos mecanismos de morte dos animais. Dentre essas alterações a hipertensão pulmonar e modificações hemodinâmicas diagnosticadas através do exame histopatológico foram as mais frequentes. | The death mechanisms in cloned animals are not well elucidated. There are few cases describing organ malformation, size and weight alterations in these animals. Pathologic studies are necessary to understand the high level of unsuccessful results using the NTSC (nuclear transfer somatic cell) technique. The present study was carried out to describe alterations present in a group of animals generated by NTSC technique that deceased between 0 to 19 days of life, using anatomopathologic examination. This experiment was conducted at Tambaú Farm in São Paulo State between years 2004 and 2008. Initially there were twenty one Nelore breed Bos indicus animals, but 11 of them deceased and ten survived and showed satisfactory clinical evolution in perinatal period. Animals necropsies and histopathologic analyses where performed. The results revealed a high prevalence of cardiopulmonary alterations, which were predominantly lung hypertension and hemodynamic profile changes, revealed by histopathologic analyses.
显示更多 [+] 显示较少 [-]Patologia de neonatos bovinos originados por meio da técnica de transferência nuclear de células somáticas: clonagem 全文
2010
Caio Rodrigues dos Santos | Fabrizio Grandi | Maria Angélica Miglino | Flávio Vieira Meirelles | Paulo César Maiorka
Os mecanismos de morte em animais clonados a partir de células somáticas são poucos elucidados. Malformações de órgãos, alterações de tamanho e peso desses animais foram anomalias já descritas, porém em casos isolados. Desse modo, estudos nos níveis anatomo e histopatológicos são de suma importância para ajudar a compreensão dos fatores responsáveis pelos altos índices de insucessos com a utilização da TNCS (transferência nuclear de células somáticas). Assim, o presente trabalho foi realizado com o objetivo de descrever, por meio de exames anatomopatológicos, as alterações presentes em um grupo de animais gerados por TNCS, que vieram a óbito entre 1 e 19 dias de vida. Esse experimento foi realizado entre os anos de 2004 e 2008 na fazenda Tambaú, cidade de Tambaú, Estado de São Paulo. No total foram gerados 21 animais da raça Nelore (Bos indicus), sendo que 11 vieram a óbito e dez apresentaram boa evolução clínica no período perinatal. Foram realizadas as necropsias dos animais e posterior análise histopatológica de tecidos alterados. Esse estudo mostrou alta prevalência de alterações cardiopulmonares, que provavelmente foram determinantes nos mecanismos de morte dos animais. Dentre essas alterações a hipertensão pulmonar e modificações hemodinâmicas diagnosticadas através do exame histopatológico foram as mais frequentes.
显示更多 [+] 显示较少 [-]Concentração de ceruplasmina em cães com linfoma multicêntrico submetidos à quimioterapia | Ceruloplasmin concentration in dogs with multicentric lymphoma undergoing chemotherapy 全文
2010
Lucas, Sílvia Regina Ricci | Merlo, Alexandre | Mirandola, Regina Mieko Sakata | Gasparin, Thais Paione
Concentração de ceruplasmina em cães com linfoma multicêntrico submetidos à quimioterapia | Ceruloplasmin concentration in dogs with multicentric lymphoma undergoing chemotherapy 全文
2010
Lucas, Sílvia Regina Ricci | Merlo, Alexandre | Mirandola, Regina Mieko Sakata | Gasparin, Thais Paione
Ceruloplasmina (Cp) é uma proteína positiva de fase aguda, responsável pelo transporte de cobre e proteção das células e tecidos contra compostos oxidantes. O objetivo deste estudo foi avaliar as concentrações de Cp no momento do diagnóstico e durante a quimioterapia em cães com linfoma multicêntrico (LM). Cp foi mensurada utilizando-se a técnica da orto dianisina em dois grupos de cães: dez cães sadios (controle) e 13 cães com LM. Todos os cães foram submetidos à quimioterapia. Cães com sintomas de doenças intercorrentes ou que haviam sido previamente tratados com prednisona foram excluídos do estudo. Cp foi mensurada antes do início do tratamento e uma vez por semana durante o primeiro mês de quimioterapia e depois a intervalos de três semanas até a recidiva.para cães com LM, e até 16 semanas nos cães do grupo controle. ANOVA seguida pelo teste de Tukey foi usada para comparar os grupos. Não houve diferença entre a media das concentrações de Cp em cães com LM ao diagnóstico quando comparados aos cães sadios (p >; 0.05). Os níveis de Cp diminuíram significativamente na quarta semana de tratamento comparado ao momento do diagnóstico. Aumentos nas concentrações de Cp não foram observados na recidiva. Durante o tratamento, as concentrações de Cp em cães com linfoma não diferiram daquelas observadas nos animais do grupo controle submetidos à quimioterapia. Concluiu-se que os níveis de Cp nos cães com LM ao diagnóstico foram similares aos cães sadios, diminuiu quando se obteve a remissão e não se alterou na recidiva da doença. | Ceruloplasmin (Cp) is a positive acute phase protein, responsible for the transport of copper and protection of cells and tissue against oxidant compounds. The aim of this study was to evaluate Cp concentrations at diagnosis and during chemotherapy in dogs with multicentric lymphoma (ML). Cp was measured using orto dianisine technique, in two groups of dogs: ten healthy dogs (control) and 13 dogs with ML. All dogs were submitted to chemotherapy. Dogs with signs of concurrent disease or that have been previously treated with prednisone were excluded from the study. Cp measurement was done before treatment and once a week, during the first month of chemotherapy, and each 3-week intervals until the relapse for dogs with ML, and until the 16th week in control dogs. ANOVA test followed by multiple Tukey's tests were used to compare the groups. There was no difference between the mean of Cp concentration in dogs with ML at the diagnosis when compared to healthy dogs (p >; .05). Levels of Cp decreased significantly at 4th week when compared to the first week, but Cp increase was not observed at the relapse. At all other times during the treatment, Cp concentrations for dogs with lymphoma were not significantly different from controls submitted to chemotherapy. As conclusion, Cp levels in ML at diagnosis were similar to healthy dogs, decreased when lymphoma remission was achieved and there was no change at the relapse.
显示更多 [+] 显示较少 [-]Concentração de ceruplasmina em cães com linfoma multicêntrico submetidos à quimioterapia 全文
2010
Sílvia Regina Ricci Lucas | Alexandre Merlo | Regina Mieko Sakata Mirandola | Thais Paione Gasparin
Ceruloplasmina (Cp) é uma proteína positiva de fase aguda, responsável pelo transporte de cobre e proteção das células e tecidos contra compostos oxidantes. O objetivo deste estudo foi avaliar as concentrações de Cp no momento do diagnóstico e durante a quimioterapia em cães com linfoma multicêntrico (LM). Cp foi mensurada utilizando-se a técnica da orto dianisina em dois grupos de cães: dez cães sadios (controle) e 13 cães com LM. Todos os cães foram submetidos à quimioterapia. Cães com sintomas de doenças intercorrentes ou que haviam sido previamente tratados com prednisona foram excluídos do estudo. Cp foi mensurada antes do início do tratamento e uma vez por semana durante o primeiro mês de quimioterapia e depois a intervalos de três semanas até a recidiva.para cães com LM, e até 16 semanas nos cães do grupo controle. ANOVA seguida pelo teste de Tukey foi usada para comparar os grupos. Não houve diferença entre a media das concentrações de Cp em cães com LM ao diagnóstico quando comparados aos cães sadios (p >; 0.05). Os níveis de Cp diminuíram significativamente na quarta semana de tratamento comparado ao momento do diagnóstico. Aumentos nas concentrações de Cp não foram observados na recidiva. Durante o tratamento, as concentrações de Cp em cães com linfoma não diferiram daquelas observadas nos animais do grupo controle submetidos à quimioterapia. Concluiu-se que os níveis de Cp nos cães com LM ao diagnóstico foram similares aos cães sadios, diminuiu quando se obteve a remissão e não se alterou na recidiva da doença.
显示更多 [+] 显示较少 [-]Polidiariose em ostras Crassostrea gigas cultivadas na Praia da Ponta do Sambaqui, Florianópolis, Santa Catarina - Brasil | Polydiariosis in cultured oyster Crassostrea gigas from Ponta do Sambaqui, Florianópolis, SC - Brasil 全文
2010
Maciel, Maria Luiza Toschi | Ibbotson, Dominique Pires | Magalhães, Aimê Rachel Maggenta
Polidiariose em ostras Crassostrea gigas cultivadas na Praia da Ponta do Sambaqui, Florianópolis, Santa Catarina - Brasil | Polydiariosis in cultured oyster Crassostrea gigas from Ponta do Sambaqui, Florianópolis, SC - Brasil 全文
2010
Maciel, Maria Luiza Toschi | Ibbotson, Dominique Pires | Magalhães, Aimê Rachel Maggenta
A infestação por poliquetas do gênero Polydora em ostras C. gigas de cultivo foi acompanhada por meio de coletas mensais enquanto os parâmetros físico-químicos da água do mar foram monitorados semanalmente. Foi determinada a área total ocupada pelas bolhas e tubos na superfície interna das valvas, observando os possíveis danos às principais características fisiológicas da ostra. Houve prevalência do anelídeo Polydora sp. (Polychaeta: Spionidae) em todos os meses amostrados, chegando a 100% no período de águas mais frias. As análises histológicas mostraram que os tecidos e órgãos estavam intactos, ocorrendo a formação de gametas. Nas ostras severamente infestadas, foi possível observar intensa fibrose na região do manto, mostrando reparo do tecido. | The infestation of polychaetes Polydora in oyster C. gigas within cultivation was accompanied by monthly samples whereas the physical and chemical parameters of seawater were monitored weekly. The total area occupied by bubbles and tubes in the inner surface of the valve was determined, indicating the possible damage to the main physiological characteristics of oysters. It was observed prevalence of annelid Polydora sp. (Polychaeta: Spionidae) in all samples each month, reaching 100% in the period of cooler waters. The histological analysis showed that the tissues and organs were intact, occurring the formation of gametes. In oysters severely infested, it was possible to observe intense fibrosis in the mantle, showing repair of the tissue.
显示更多 [+] 显示较少 [-]Polidiariose em ostras Crassostrea gigas cultivadas na Praia da Ponta do Sambaqui, Florianópolis, Santa Catarina - Brasil 全文
2010
Maria Luiza Toschi Maciel | Dominique Pires Ibbotson | Aimê Rachel Maggenta Magalhães
A infestação por poliquetas do gênero Polydora em ostras C. gigas de cultivo foi acompanhada por meio de coletas mensais enquanto os parâmetros físico-químicos da água do mar foram monitorados semanalmente. Foi determinada a área total ocupada pelas bolhas e tubos na superfície interna das valvas, observando os possíveis danos às principais características fisiológicas da ostra. Houve prevalência do anelídeo Polydora sp. (Polychaeta: Spionidae) em todos os meses amostrados, chegando a 100% no período de águas mais frias. As análises histológicas mostraram que os tecidos e órgãos estavam intactos, ocorrendo a formação de gametas. Nas ostras severamente infestadas, foi possível observar intensa fibrose na região do manto, mostrando reparo do tecido.
显示更多 [+] 显示较少 [-]Parasites of domestic and wild animals in South Africa. XLVIII . Ticks (Acari: Ixodidae) infesting domestic cats and wild felids in southern Africa 全文
2010
Horak, Ivan G. | Heyne, Heloise | Donkin, Edward F.
Parasites of domestic and wild animals in South Africa. XLVIII . Ticks (Acari: Ixodidae) infesting domestic cats and wild felids in southern Africa 全文
2010
Horak, Ivan G. | Heyne, Heloise | Donkin, Edward F.
Ticks collected from domestic cats (Felis catus), cheetahs (Acinonyx jubatus),caracals (Caracal caracal), African wild cats (Felis lybica), black-footed cats (Felis nigripes), a serval (Leptailurus serval), lions(Panthera leo), and leopards (Panthera pardus) were identified and counted. Thirteen species of ixodid ticks and one argasid tick were identified from domestic cats and 17 species of ixodid ticks from wild felids. The domestic cats and wild felids harboured 11 ixodid species in common. The adults of Haemaphysalis elliptica, the most abundant tick species infesting cats and wild felids, were most numerous on a domestic cat in late winter and in mid-summer, during 2 consecutive years. The recorded geographic distribution of the recently described Haemaphysalis colesbergensis, a parasite of cats and caracals, was extended by 2 new locality records in the Northern Cape Province,South Africa.
显示更多 [+] 显示较少 [-]Parasites of domestic and wild animals in South Africa. XLVIII . Ticks (Acari: Ixodidae) infesting domestic cats and wild felids in southern Africa 全文
2010
Ivan G. Horak | Heloise Heyne | Edward F. Donkin
Ticks collected from domestic cats (Felis catus), cheetahs (Acinonyx jubatus),caracals (Caracal caracal), African wild cats (Felis lybica), black-footed cats (Felis nigripes), a serval (Leptailurus serval), lions(Panthera leo), and leopards (Panthera pardus) were identified and counted. Thirteen species of ixodid ticks and one argasid tick were identified from domestic cats and 17 species of ixodid ticks from wild felids. The domestic cats and wild felids harboured 11 ixodid species in common. The adults of Haemaphysalis elliptica, the most abundant tick species infesting cats and wild felids, were most numerous on a domestic cat in late winter and in mid-summer, during 2 consecutive years. The recorded geographic distribution of the recently described Haemaphysalis colesbergensis, a parasite of cats and caracals, was extended by 2 new locality records in the Northern Cape Province,South Africa.
显示更多 [+] 显示较少 [-]Comparative ultrastructure of fibrin networks of a dog after thrombotic ischaemic stroke 全文
2010
Pretorius, Etheresia | Windberger, Ursula B. | Oberholzer, Hester M. | Auer, Roland E.
Comparative ultrastructure of fibrin networks of a dog after thrombotic ischaemic stroke 全文
2010
Pretorius, Etheresia | Windberger, Ursula B. | Oberholzer, Hester M. | Auer, Roland E.
A cerebrovascular accident or stroke is a rare condition in dogs, but previous studies suggest that it is now increasingly being recognised. Platelets and fibrin networks are involved in haemostasis,which is disrupted during a thrombotic event. In this study we investigate the ultrastructure of the fibrin networks of a dog that had suffered ischaemic stroke, following suspected thromboembolism from clots that became dislodged during catheter maintenance (flushing with heparinised saline) 2 days after carotid artery catheter insertion. Fibrin networks of blood samples that were collected immediately after the stroke, 15 min after treatment with streptokinase and 24 h after treatment, were studied. The results were compared to those of two control dogs. During a stroke, fibrin morphology changes to form a thick, matted layer.Post-treatment ultrastructure shows that the fibrin morphology returns to that comparable to controls. Our results show that during thrombotic risk, fibrin network morphology changes visibly and reduces the fibrinolytic activity of the coagulation system.
显示更多 [+] 显示较少 [-]Comparative ultrastructure of fibrin networks of a dog after thrombotic ischaemic stroke 全文
2010
Etheresia Pretorius | Ursula B. Windberger | Hester M. Oberholzer | Roland E. Auer
A cerebrovascular accident or stroke is a rare condition in dogs, but previous studies suggest that it is now increasingly being recognised. Platelets and fibrin networks are involved in haemostasis,which is disrupted during a thrombotic event. In this study we investigate the ultrastructure of the fibrin networks of a dog that had suffered ischaemic stroke, following suspected thromboembolism from clots that became dislodged during catheter maintenance (flushing with heparinised saline) 2 days after carotid artery catheter insertion. Fibrin networks of blood samples that were collected immediately after the stroke, 15 min after treatment with streptokinase and 24 h after treatment, were studied. The results were compared to those of two control dogs. During a stroke, fibrin morphology changes to form a thick, matted layer.Post-treatment ultrastructure shows that the fibrin morphology returns to that comparable to controls. Our results show that during thrombotic risk, fibrin network morphology changes visibly and reduces the fibrinolytic activity of the coagulation system.
显示更多 [+] 显示较少 [-]The use of a rat model to evaluate the in vivo toxicity and wound healing activity of selected Combretum and Terminalia (Combretaceae) species extracts 全文
2010
Masoko, Peter | Picard, Jackie | Eloff, Jacobus N.
The use of a rat model to evaluate the in vivo toxicity and wound healing activity of selected Combretum and Terminalia (Combretaceae) species extracts 全文
2010
Masoko, Peter | Picard, Jackie | Eloff, Jacobus N.
Wound healing is a fundamental response to tissue injury and several natural products have been shown to accelerate the healing process. The present study was undertaken to determine the safety and efficacy of the topical treatment of acetone leaf extracts of Combretum imberbe, Combretum nelsonii,Combretum albopuntactum and Terminalia sericea based on their in vitro antimicrobial activity. Four circular full-thickness skin wounds were made on the backs of eight anaesthetised Wistar rats using aseptic techniques. The treatments were administrated topically using 10% and 20% concentrations of each extract in aqueous cream in separate treatments. Indications of erythema, exudate, crust formation,swelling and ulceration were used to determine the wound healing process. All of the wounds closed completely within 17 days. Throughout the experiment, a subcutaneous probe was used to determine that the body temperature and body weight of the rats were within the normal range. C. imberbe and C. nelsonii extracts accelerated wound healing, but there was no significant difference in wound contraction using 10% and 20% concentrations of the extracts in cream. The results also showed the potential usefulness of this model to measure accelerating wound healing.The extracts could perhaps overcome defects associated with healing failure in chronic wounds and prevent secondary bacterial and fungal infections.
显示更多 [+] 显示较少 [-]The use of a rat model to evaluate the <i>in vivo</i> toxicity and wound healing activity of selected <i>Combretum</i> and <i>Terminalia </i>(Combretaceae) species extracts 全文
2010
Peter Masoko | Jackie Picard | Jacobus N. Eloff
Wound healing is a fundamental response to tissue injury and several natural products have been shown to accelerate the healing process. The present study was undertaken to determine the safety and efficacy of the topical treatment of acetone leaf extracts of <em>Combretum imberbe, Combretum nelsonii,Combretum albopuntactum</em> and <em>Terminalia sericea</em> based on their in <em>vitro</em> antimicrobial activity. Four circular full-thickness skin wounds were made on the backs of eight anaesthetised Wistar rats using aseptic techniques. The treatments were administrated topically using 10% and 20% concentrations of each extract in aqueous cream in separate treatments. Indications of erythema, exudate, crust formation,swelling and ulceration were used to determine the wound healing process. All of the wounds closed completely within 17 days. Throughout the experiment, a subcutaneous probe was used to determine that the body temperature and body weight of the rats were within the normal range. <em>C. imberbe</em> and <em>C. nelsonii</em> extracts accelerated wound healing, but there was no significant difference in wound contraction using 10% and 20% concentrations of the extracts in cream. The results also showed the potential usefulness of this model to measure accelerating wound healing.The extracts could perhaps overcome defects associated with healing failure in chronic wounds and prevent secondary bacterial and fungal infections.
显示更多 [+] 显示较少 [-]Seroprevalence survey of Chlamydophila abortus infection in breeding goats on commercial farms in the Otavi Veterinary District, northern Namibia 全文
2010
Samkange, Alaster | Katsande, Tendai C. | Tjipura-Zaire, Georgina | Crafford, Jan E.
Seroprevalence survey of Chlamydophila abortus infection in breeding goats on commercial farms in the Otavi Veterinary District, northern Namibia 全文
2010
Samkange, Alaster | Katsande, Tendai C. | Tjipura-Zaire, Georgina | Crafford, Jan E.
A total of 1 076 sera from breeding goats were randomly collected from 24 different farms and tested with CHEKIT®-ELISA (IDEXX Laboratories B.V., 1 119 NE Schiphol-Rijk, Nederland) for antibodies against Chlamydophila abortus. The farms were divided into two categories of twelve farms each,based on their previous history of observed abortions over the previous 12 months: those with low ( 5%) levels of abortion and those with high (≥ 5%) levels of abortion. The farmers were also interviewed on their level of awareness about chlamydophilosis, its zoonotic importance and vaccination measures against the disease. The study detected overall seroprevalence levels of 25% for the farms and 8% for the individual animals (at 95% confidence). A total of six out of twentyfour farms (25%) had at least one positive breeding animal. Only five out of the twenty-four (20.8%)farmers interviewed were aware of chlamydophilosis and its zoonotic dangers. None of the 24 farmers interviewed practised any vaccination against chlamydophilosis. There was a significantly higher number of seropositive animals from farms with high levels of abortion, compared to those animals from farms with low levels of abortion (p = 0.0001). This study underscores the need for a higher level of farmer awareness and training on chlamydophilosis and its zoonotic dangers.
显示更多 [+] 显示较少 [-]Seroprevalence survey of <i>Chlamydophila abortus</i> infection in breeding goats on commercial farms in the Otavi Veterinary District, northern Namibia 全文
2010
Alaster Samkange | Tendai C. Katsande | Georgina Tjipura-Zaire | Jan E. Crafford
A total of 1 076 sera from breeding goats were randomly collected from 24 different farms and tested with CHEKIT®-ELISA (IDEXX Laboratories B.V., 1 119 NE Schiphol-Rijk, Nederland) for antibodies against Chlamydophila abortus. The farms were divided into two categories of twelve farms each,based on their previous history of observed abortions over the previous 12 months: those with low (< 5%) levels of abortion and those with high (≥ 5%) levels of abortion. The farmers were also interviewed on their level of awareness about chlamydophilosis, its zoonotic importance and vaccination measures against the disease. The study detected overall seroprevalence levels of 25% for the farms and 8% for the individual animals (at 95% confidence). A total of six out of twentyfour farms (25%) had at least one positive breeding animal. Only five out of the twenty-four (20.8%)farmers interviewed were aware of chlamydophilosis and its zoonotic dangers. None of the 24 farmers interviewed practised any vaccination against chlamydophilosis. There was a significantly higher number of seropositive animals from farms with high levels of abortion, compared to those animals from farms with low levels of abortion (p = 0.0001). This study underscores the need for a higher level of farmer awareness and training on chlamydophilosis and its zoonotic dangers.
显示更多 [+] 显示较少 [-]Prion genotypes of scrapie-infected Canadian sheep 1998–2008 全文
2010
Harrington, Noel P. | O'Rourke, Katherine I. | Feng, Yuqin | Rendulich, Jasmine | DiFruscio, Cathleen | Balachandran, Aru
This report describes the genetics of the prion protein gene (PRNP) at codons 136, 154, and 171 for sheep diagnosed with naturally acquired classical scrapie in Canada between 1998 and 2008. Genotyping analysis was performed on 249 sheep with confirmed classical scrapie infection representing 98 flocks from 6 provinces. A further case-control analysis of 3 of these flocks compared the genotypes between infected sheep (n = 72) and those of their healthy flockmates (n = 1990). The incidence of classical scrapie in the Canadian sheep population was highly associated with the ARQ haplotype (91.8%) and the ARQ/ARQ genotype (91.6%). In addition, the ARQ haplotype was found at significantly higher frequency in scrapie-infected sheep when compared with their healthy flockmates. Comparison with other published data suggests that the scrapie risk of PRNP genotypes differs between Canada and countries where the VRQ allele is associated with the highest susceptibility to infection.
显示更多 [+] 显示较少 [-]Immune response following vaccination against Salmonella Enteritidis using 2 commercial bacterins in laying hens 全文
2010
Tran, Thi Q.L. | Quessy, Sylvain | Letellier, Ann | Desrosiers, Annie | Boulianne, M (Martine)
The humoral and cell-mediated immune (CMI) response to 2 commercial killed Salmonella Enteritidis (SE) vaccines (Layermune and MBL SE4C) was evaluated in laying hens. Layers were distributed in 2 experimental groups. The first received a single immunization at 16 wk of age, while the second experimental group was immunized at 12 wk of age and again at 18 wk of age. Serum immunoglobulin (Ig)G antibodies were measured using a commercial SE ELISA kit and showed persistent levels from 3 to 32 and 34 wk post-vaccination. The vaccination protocol using 2 immunizations showed a higher seroconversion level than the single vaccination. However, our results for bacterial intracellular survival indicated that IgG titers were not linked with bacterial killing. Local IgA production was measured in the intestines and oviducts with an in-house SE whole cell antigen ELISA. Only the MBL SE4C vaccine elicited IgA antibody production when tested on intestine and oviduct mucosal secretions, 3-weeks post-vaccination in both immunization protocol groups. To evaluate the CMI response, the splenic T-cells and B-cells populations were analyzed using flow cytometry. The CD3/B-cell ratio decreased 3 wk after the second immunization in the twice vaccinated Layermune group due to an increase in B-cells.
显示更多 [+] 显示较少 [-]Expression of vascular endothelial growth factor and endothelial nitric oxide synthase is increased in the placenta of sheep at high altitude in the Andes 全文
2010
Parraguez, Victor H. | Atlagich, Miljenko A. | Urguieta, Bessie | Galleguillos, Marco | Reyes, Monica De los | Kooyman, David L. | Araneda, Silvia | Raggi, Luis A.
Fetal weight and the placenta of sheep at high altitude (HA) are affected by hypoxia. Placental changes (an increase in placental size and vascularization) are greater in ewes from populations that have lived for several generations at HA than in those exposed during just 1 gestation. This study investigated placental expression of vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS), 2 molecules involved in placental angiogenesis that could be upregulated by hypoxia. Two groups of ewes were maintained at HA (3589 m) during pregnancy: HA-native ewes (group HH) and ewes native to lowlands but moved to HA immediately after the diagnosis of pregnancy (group LH). A control group (LL) was kept at sea level. Near term, placentomes were removed, weighed, and processed for immunohistochemical detection of VEGF and eNOS, as well as for vascular area measurement. Placental weight was significantly higher in the HH group than in the LH and LL groups; between the latter 2 groups there was no significant difference. The placental area occupied by vasculature was significantly greater in both the HA groups than in the LH group; the number of placentomes was greatest in the LL group. The density of VEGF and eNOS in the placentome tissue was significantly greater in both HA groups than in the LL group. Although the density of VEGF was significantly lower in the HH group than in the LH group, no differences were observed in eNOS density between the HH and LH animals. These results demonstrate that chronic hypoxia upregulates the expression of placental VEGF and eNOS, suggesting an important role of these molecules in the placental response to HA hypoxia. In addition, an attenuated response to hypoxia in VEGF synthesis may be part of the long-term process of adaptation to HA.
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