DSA - Artigos de revista
Permanent URI for this collection
Browse
Browsing DSA - Artigos de revista by Issue Date
Now showing 1 - 10 of 18
Results Per Page
Sort Options
- Pesquisa e quantificação do agonista beta2-adrenérgico salbutamol (Albuterol) no plasma sanguíneoPublication . Correia, J.H.R.D.; Prates, J.A.M.A utilização de agonistas Beta2-adrenérgicos (por exemplo, clenbuterol, salbutamol, ractopamina, etc.) para fins ilegais, de aceleração do crescimento em animais de talho, é um gravíssimo problema da Saúde Pública Veterinária.
- Cell phenotypic change due to Cryptosporidium parvum infection in immunocompetent micePublication . Códices, Vera; Martins, Catarina; Novo, Carlos; Pinho, Mário; Sousa, Bruno de; Lopes, Ângela; Borrego, Miguel; Matos, OlgaCryptosporidium parvum is an intracellular parasite causing enteritis which can become life-threatening in immunocompromised host. Immunoregulatory T cells play a central role in the regulatory network of the host. Here, we proposed to characterize the populations of immune cells during infection and reinfection with C. parvum. Four-week-old BALB/C mice were inoculated with oocysts of C. parvum at days 0 and 22. Fecal and blood samples, spleens, and small intestines were collected for analysis. Peripheral blood and spleen cell populations were characterized by flow cytometry. After infection (days 0 to 21), mice presented higher values of neutrophils, eosinophils, NK cells and CD4+CD25high T cells in peripheral blood. After reinfection, this upward trend continued in the following days for all four populations in infected mice. At day 35, infected mice presented similar values to the control group, except for CD4+CD25high T cells, which remained higher in infected mice. A possible correlation between alterations in blood and spleen cell populations was also studied, but no consistent association could be established. Small intestine sections were screened for intracellular stages of the parasite but no evidence of pathology was observed. Here, we report information which may be important for the understanding of the specific cell-mediated response in immunocompetent mice to C. parvum infection. Although some questions remain unanswered and complementary studies are needed, our results are expected to contribute to a better understanding of innate and Treg cells role in the clearance process of this parasite.
- Natural infection of synathropic rodent species Mus musculus and Rattus norvegicus by Leishmania infantum in Sesimbra and Sintra – PortugalPublication . Helhazar, Marcos; Leitão, José; Duarte, Ana; Tavares, Luís; Fonseca, Isabel Pereira daBackground: Canine leishmaniosis caused by Leishmania infantum is a parasitic zoonotic disease transmitted by phlebotomine sandflies (Diptera: Psychodidae). Genus Phlebotomus is the biological vector in the Old World and Lutzomyia in the New World. The dog is the domestic reservoir host but other animals like the fox (Vulpes vulpes) and rodents are known to maintain the infection in both sylvatic and domestic cycles. Methods: To identify the role of synanthropic rodents Mus musculus and Rattus norvegicus as reservoir hosts for Leishmania infantum natural infection, 30 rodents were captured under a trap rodent control program in two private dog shelters from Sintra and Sesimbra, located in the Lisbon Metropolitan Area, known to be endemic for canine leishmaniosis in Portugal. Tissue samples were screened for the presence of Leishmania amastigotes by qPCR and parasitological analysis. Results: A total of 33.3% (9/27) of Mus musculus rodents revealed the presence of Leishmania spp. DNA while 29.6% (8/27) were positive in the parasitological analysis. Concerning Rattus norvegicus (n=3), one animal revealed infection only by parasitological analysis. Conclusions: Our results identified for the first time in Portugal the presence of Leishmania infection in both rodent species. As susceptible hosts, infected Mus musculus and Rattus norvegicus may increase the risk for dog and human infection in households and surrounding areas, enhancing the need for efficient rodent control measures in shelters and risk zones to prevent transmission of the infection.
- Relevance of feline interferon omega for clinical improvement and reduction of concurrent viral excretion in retrovirus infected cats from a rescue shelterPublication . Gil, Solange; Leal, Rodolfo O.; Duarte, Ana; McGahie, David; Sepúlveda, Nuno; Siborro, Inês; Cravo, Joana; Cartaxeiro, Clara; Tavares, Luís M.Feline Immnunodeficiency (FIV) and Feline Leukemia (FeLV) viruses are common infectious agents in stray cats and shelter environments. Recombinant feline interferon-x (rFeIFNx) has shown an antiviral action not only against FIV and FeLV but also against herpesvirus (FHV-1) and calicivirus (FCV). Sixteen naturally infected FIV/FeLV cats were followed during rFeIFNx therapy in order to monitor clinical signs and to correlate with excretion of concomitant viruses (FCV, FHV-1, feline coronavirus (FCoV) and parvovirus (FPV)). Cats were submitted to clinical evaluations and concomitant virus excretion assessement. Comparing D0–D65, 10/16 cats improved clinical scores. Of the 10 cats positive for FHV-1 on D0, 4 were negative and 6 reduced viral loads. Of the 11 FCoV positive cats, 9 reduced viral loads. The 13 FCV positive cats and the FPV positive cat were negative on D65. In conclusion, rFeIFNx improves clinical signs and reduces concurrent viral excretion in naturally infected retroviral cats.
- The use of oral recombinant feline interferon omega in two cats with type II diabetes mellitus and concurrent feline chronic gingivostomatitis syndromePublication . Leal, Rodolfo O.; Gil, Solange; Brito, Maria T. V.; McGahie, David; Niza, Maria M. R. E.; Tavares, LuísFeline Chronic Gingivostomatitis Syndrome (FCGS) is a common disease in clinical practice. Among the therapeutic options available, long-acting corticosteroids are frequently used due to their anti-inflammatory and immunosuppressive properties. Although they may improve the clinical symptoms, they can lead to a progressive form of the disease that becomes refractory to treatment. Furthermore, their direct relationship with type II diabetes mellitus (DM) is well known. Consequently, these drugs are controversial and not recommended for routine management of FCGS. Recombinant feline interferon-omega (rFeIFN-ω) is an immunomodulatory compound. Recently, its daily oral administration has been shown to be successful in treating refractory cases of FCGS. This case study describes two clinical cases of type II DM complicated by FCGS. Both animals were calicivirus positive and they had been previously treated with long-acting corticosteroids, which may have been the major cause of DM. The two cats were treated with glargine insulin (Lantus, starting dose 1 IU/cat twice daily (BID)), achieving remission 10 and 18 weeks later respectively. Considering the difficulty with control of FCGS in these animals, an oral daily dose of rFeIFN-ω was started as an alternative to long-acting corticosteroids. In both cats oral clinical signs gradually improved and 60 days after the start of therapy the owners reported a significant relief of pain during mastication. According to the authors’ knowledge, this is the first case report that describes the successful use of rFeIFN-ω in the management of FCGS in type II diabetic cats, in which long-acting corticosteroids are contraindicated.
- Taeniid species of the Iberian wolf (Canis lupus signatus) in Portugal with special focus on Echinococcus spp.Publication . Guerra, Diogo; Armua-Fernandez, Maria Teresa; Silva, Marta; Bravo, Inês; Santos, Nuno; Deplazes, Peter; Carvalho, Luís Manuel Madeira deTaeniid species represent relevant pathogens in human and animals, circulating between carnivorous definitive hosts and a variety of mammalian intermediate hosts. In Portugal, however, little is known about their occurrence and life cycles, especially in wild hosts. An epidemiological survey was conducted to clarify the role of the Iberian wolf as a definitive host for taeniid species, including Echinococcus spp. Wolf fecal samples (n = 68) were collected from two regions in Northern Portugal. Taeniid eggs were isolated through a sieving-flotation technique, and species identification was performed using multiplex- PCR followed by sequencing of the amplicons. Taenia hydatigena (in 11.8% of the samples), Taenia serialis (5.9%), Taenia pisiformis (2.9%), Taenia polyacantha (1.5%) and Echinococcus intermedius (Echinococcus granulosus ‘pig strain’, G7) (1.5%) were detected. This is the first study to characterize the taeniid species infecting the Portuguese Iberian wolf, with the first records of T. polyacantha and E. intermedius in this species in the Iberian Peninsula. Iberian wolves can be regarded as relevant hosts for the maintenance of the wild and synanthropic cycles of taeniids in Portugal.
- Oral Recombinant Feline Interferon-Omega as an alternative immune modulation therapy in FIV positive cats : clinical and laboratory evaluationPublication . Gil, S.; Leal, R.O.; McGahie, D.; Sepúlveda, N.; Duarte, A.; Niza, M.M.R.E.; Tavares, L.Recombinant-Feline Interferon-Omega (rFeIFN-ω) is an immune-modulator licensed for use subcutaneously in Feline Immunodeficiency virus (FIV) therapy. Despite oral protocols have been suggested, little is known about such use in FIV-infected cats. This study aimed to evaluate the clinical improvement, laboratory findings, concurrent viral excretion and acute phase proteins (APPs) in naturally FIV-infected cats under oral rFeIFN-ω therapy (0.1 MU/cat rFeIFN-ω PO, SID, 90 days). 11 FIV-positive cats were treated with oral rFeIFN-ω (PO Group). Results were compared to previous data from 7 FIV-positive cats treated with the subcutaneous licensed protocol (SC Group). Initial clinical scores were similar in both groups. Independently of the protocol, rFeIFN-ω induced a significant clinical improvement of treated cats. Concurrent viral excretion and APP’s variation were not significant in the PO Group. Oral rFeIFN-ω can be an effective alternative therapy for FIV-infected cats, being also an option for treatment follow-up in cats submitted to the licensed protocol.
- Parasitas gastrointestinais em produção de frango ao ar livrePublication . Lozano, João; Gomes, Lídia; Madeira de Carvalho, LuísA investigação em sanidade animal realizada a nível nacional em sistemas extensivos de produção de frango é essencial, atendendo à frequente longa exposição dos animais ao ambiente exterior e aos parasitas que o contaminam. Estudos parasitológicos são extremamente relevantes de forma a conhecer quais as espécies parasitárias mais prevalentes e ajudar os produtores a definirem melhores medidas profiláticas. Esta pesquisa procurou identificar os parasitas gastrointestinais associados a este tipo de produção aviária e ocorreu numa exploração agropecuária localizada na extremidade noroeste do distrito de Lisboa, onde foram avaliados Frangos do Campo através de amostragem fecal aos 75 e 85 dias de idade. O parasitismo gastrointestinal foi analisado através de métodos coprológicos qualitativos, quantitativos e coproculturas para obtenção de oocistos esporulados e larvas L3 de nematodes estrongilídeos. Na 1ª amostragem, a prevalência de Eimeria spp. totalizou 40,0%, sendo Eimeria mitis (13,3%) e E. maxima (11,7%) as mais prevalentes, tendo-se identificado também ovos de Capillaria sp., (1,7 % de prevalência). Nas coproculturas de oocistos, esporularam as seguintes espécies: E. necatrix, E. mitis, E. praecox, E. maxima, E. acervulina e E. tenella. Na 2ª amostragem, as coccídeas continuaram a ser o grupo mais prevalente, 90,0% de amostras positivas com oito espécies identificadas, sendo de novo E. mitis a espécie mais frequente (41,7%), seguida por E. acervulina (26,7%) e E. tenella (25%). Foram também observados ovos de Heterakis sp. (3,33%) e novamente de Capillaria sp. (10,0%) A carga parasitária fecal de oocistos na 1ª e 2ª amostragens foi de 370,8 ± 2055,3 OoPG e 599,2 ± 1289,2 OoPG, respetivamente, verificando-se um aumento superior a 60% do valor médio deste parâmetro parasitológico da 1ª para a 2ª colheita. O crescimento da erva, a idade e densidade animal, bem como o tempo de exposição a parasitas com períodos pré-patentes curtos, constituíram fatores chave para o aumento da prevalência de oocistos de Eimeria spp. e ovos de helmintes entre as duas amostragens, em particular de espécies com reconhecida patogenicidade. Isto permite-nos concluir que no final da fase de engorda, as cargas parasitárias são as mais elevadas detetadas neste sistema de produção de Frango do Campo, podendo desencadear patologia associada e interferir com a sua performance produtiva.
- Gastrointestinal parasites of free-range chickens : a worldwide issuePublication . Lozano, João; Anaya, Adriana; Palomero Salinero, Antonio; Lux Hoppe, Estevam Guilherme; Gomes, Lídia; Paz-Silva, Adolfo; Rebelo, Maria Teresa; Madeira de Carvalho, LuísGastrointestinal parasites with direct and/or indirect life cycles, namely Eimeria spp., Ascaridia galli, Heterakis gallinarum and Capillaria spp., are responsible for the most frequent and heavy economic losses in aviculture. The current review aimed to collect information about gastrointestinal parasites affecting poultry, as well as, research studies regarding parasitic diseases in free-range chicken production. From the references used in this review, 20% highlight research studies correlating prevalence of gastrointestinal parasites in free-range chickens and factors such as the production system, age and animal density, hygienic conditions and weather. Coccidiosis is responsible for the major economic losses in poultry farms. Diseases have different clinical signs and result in variable impacts on animals. Control programs include mainly vaccination, anti-coccidia and anthelminthic drugs, as well as, house cleaning and disinfection. This review concluded that coccidia and helminths are a global threat to free-range poultry production. More research in this area is necessary in order to understand the major factors influencing the prevalence of parasitic diseases in this type of poultry production. Also the search for new control strategies must be a priority, mainly using natural antiparasitic compounds and biological control approaches.
- Diagnosis of coccidiosis by Eimeria spp. in free-range chickens using Mini-FLOTAC and McMaster techniques - preliminary resultsPublication . Lozano, João; Anaya, Adriana; Rinaldi, Laura; Cringoli, Giuseppe; Gomes, Lídia; Oliveira, Manuela; Paz-Silva, Adolfo; Rebelo, Maria Teresa; Madeira de Carvalho, LuísMini-FLOTAC is emerging as a more sensitive and accurate tool to identify gastrointestinal parasites in faecal samples from domestic animals, in comparison with the McMaster method. However, research regarding its specific application in poultry samples, particularly from free-range chickens, is scarce. The current research aimed to test the use of Mini-FLOTAC for the identification of Eimeria spp. in free-range chickens and compare its results with McMaster. For this study, 40 faecal samples were collected from free-range chickens in a poultry farm located in North-Western Lisbon (Portugal). Each sample was processed with McMaster and Mini-FLOTAC techniques for the detection and count of coccidian Eimeria spp. oocysts. The resulting OPG (oocysts per gram of faeces) data obtained by the two techniques were compared using the Wilcoxon Test and correlated with the Spearman Test, and Mini-FLOTAC’s relative sensitivity was assessed, using a significance level of p<0.05. The average OPG was higher with Mini-FLOTAC and doubled the one obtained using the McMaster method (2669.3 OPG and 1220 OPG, respectively), although these results were not significant. Mini-FLOTAC’s relative sensitivity obtained in this study reached 86% (70.5-95.3%, 95%CI), although this result was not statistically significant. However, correlation of OPG counts between Mini-FLOTAC and McMaster, was significant. These preliminary results suggest the potential interest in the use of Mini-FLOTAC for the diagnosis of coccidiosis by Eimeria spp. in poultry, based on its assessment in a free-range poultry production system.