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Comparison of different methods for exogenous DNA uptake by bovine spermatozoa Полный текст
2015
Renata Simões | Weber Beringui Feitosa | Marcella Pecora Milazzotto | Alessandra Corallo Nicacio | Flavia Regina Oliveira de Barros | José Sergio de Arruda Gonçalves | Mariana Groke Marques | José Antônio Visintin | Mayra Elena Ortiz D'Ávila Assumpção
Although genetic manipulation of farm animals is of great interest for animal production and the pharmaceutical industry, its efficiency remains far from satisfactory. Pronuclear injection, which is the most widely used technique for such modification, mainly in mice, remains limited for this species. Some alternatives have been developed such as sperm mediated gene transfer, in which the spermatozoa are used as vectors for DNA delivery during in vitro fertilization. Mature sperm cells are able to spontaneously bind exogenous DNA molecules which may be internalized into sperm nuclei. Given the potential of sperm mediated gene transfer for livestock animals transgenesis, the aim of this study was to evaluate four methods of DNA uptake for sperm mediated gene transfer in bovine: incubation with DNA, plasma membrane alteration induced by calcium ionophore followed by incubation with DNA, electroporation and lipofection. Spermatozoa not exposed to exogenous DNA were used as control group. Cleavage, blastocyst and hatching rates were recorded at 72 hours post insemination (hpi), days 9 and 12 of embryo culture, respectively. Exogenous DNA-positive embryos were evaluated by PCR. No effect of treatment was observed on cleavage, blastocyst and hatching rates. In addition, percentage of DNA positive blastocysts did not differ among experimental groups. In spite of the low number of positive embryos, our results show that all treatments presented similar efficiencies for DNA delivery during in vitro fertilization. In conclusion, although the development rates were similar and constant in all groups, other factors such as exogenous DNA sequence, size and concentration should be considered to improve sperm mediated gene transfer.
Показать больше [+] Меньше [-]Occurrence of antibodies anti-Toxoplasma gondii and anti-Neospora caninum in dogs from Natal, RN, Brazil Полный текст
2015
Marcos Gomes Lopes | Maurício Hernandez | Júlia Tereza Ribeiro de Lima | José Henrique Hildebrand Grisi Filho | Solange Maria Gennari
The occurrence of anti-Toxoplasma gondii and Neospora caninum in dogs from the municipality of Natal, RN, Brazil, was determined. Information about the presence of these coccidia in this species was not known. Blood samples were collected from 29 domiciled dogs which inhabit areas that surround two important protected areas of Atlantic Forest (Parque da Cidade and Parque das Dunas) and another 73 dogs that were sacrificed due to Leishmania spp. infection, in Center for Control of Zoonosis (CCZ) for the municipality of Natal. It was only possible to obtain information about the gender of dogs that live in the parks area. The presence of antibodies against each parasite was determined by indirect Fluorescence Antibody Test (IFAT), with a cutoff of 16 for T. gondii and 50 for N. caninum. Of the 102 dogs examined, 13 (12.7%, 95% CI 7.0-20.8%) were T. gondii positive and three (2.9%, CI 0.6-8.4%) for N. caninum. Association between: localities of obtaining samples (parks x CCZ) and sex of animals, with the occurrence of antibodies against each of the parasites, was determined by the Fisher exact test. For T. gondii association was found with males (p = 0.027) and dogs living close to parks (p = 0.008) had higher rates of infection. Associations were not observed in relation to N. caninum.
Показать больше [+] Меньше [-]Salmonella Agona em Perus (Meleagris gallopavo) de criações comerciais no Brasil Полный текст
2015
Mirela Caroline Vilela de Oliveira | Marcos Paulo Vieira Cunha | Maria Gabriela Xavier de Oliveira | Pedro Henrique de Lima Filsner | Andrea Micke Moreno | Paulo Eduardo Brandão | Terezinha Knöbl
Salmonella spp. é um dos principais agentes envolvidos em casos de doenças de origem alimentar em humanos, responsável por perdas significativas na avicultura. O objetivo deste estudo foi investigar a presença de Salmonella spp. em fezes de perus comerciais no Brasil. Foram colhidos suabes fecais de 14 lotes de perus comerciais (pool de seis aves/lote). Os suabes foram submetidos aos procedimentos de isolamento bacteriológico convencionais e a detecção de DNA do agente foi realizada através da técnica de PCR. Salmonella spp. foi detectada em um total de nove lotes dos 14 avaliados. As amostras foram negativas na identificação molecular dos sorovares Enteritidis e Typhimurium. Os isolados foram encaminhados ao laboratório de referência para sorotipagem e identificados como S. Agona; um patógeno considerado emergente em vários países.
Показать больше [+] Меньше [-]Expression of proliferating cell nuclear antigen in the endometrium of mares during estrus and at early diestrus Полный текст
2015
Geórgia Duna Mansour | Lio Moreira | Ana Maria Reis Ferreira
Immunohistochemical expression of proliferating cell nuclear antigen (PCNA) was evaluated in the endometrium of mares during estrus and at early diestrus. Three samples were collected by endometrial biopsy from 10 mares, on estrus/ second day, in the ovulation day and seven days after the ovulation day. PCNA expression was high in luminal epithelium and low in endometrial glands on samples taken on estrus/second day and on the ovulation day (p < 0.05). For samples collected on the seventh day following ovulation, the averaged PCNA immunostaining was higher in glandular epithelium (p < 0.05). The study revealed that luminal epithelial cells exhibit higher proliferation during estrus and glandular epithelial cells exhibited higher proliferation during diestrus.
Показать больше [+] Меньше [-]c-Kit immunoexpression patterns differ in melanotic and amelanotic canine oral melanomas Полный текст
2015
Tarso Felipe Teixeira | Luciana Boffoni Gentile | Marco Antonio Leon Roman | Marco Antonio Gioso | Maria Lucia Zaidan Dagli
Melanomas are the most common oral malignancy in dogs. Cell proliferation and connexin expression has been shown to differ in canine melanotic and amelanotic oral melanomas. This study aimed to analyze the c-Kit protein expression in melanotic and amelanotic melanomas from canine buccal cavity. A total of 34 canine buccal melanomas (19 melanotic and 15 amelanotic).were collected. The amelanotic melanomas presented faster evolution and higher incidence of metastasis than melanotic tumors. A significantly higher number of c-Kit positive cells were observed in amelanotic neoplasms. In addition, the intensity of c-Kit immunolabeling was predominantly stronger in amelanotic melanomas. These results confirm a potential role for c-Kit in canine oral melanomas with clear differences in expression patterns between the two histological types of tumor, melanotic and amelanotic. This study highlights the importance of a detailed study of c-Kit mutations in canine oral melanomas to better understand the molecular mechanisms implicated in the development of this disease.
Показать больше [+] Меньше [-]Consumption of animal products and frauds: DNA-based methods for the investigation of authenticity and traceability in dairy and meat-derived products – a review Полный текст
2015
Ana Carolina da Silva Carvalho | Solange Maria Gennari | Vânia Margaret Flosi Paschoalin
The increase in the population’s acquisition power in emerging countries like Brazil has resulted in increased consumption of meat, milk and their derivatives, and a consequent growing surveillance regarding the responsibility of maintaining the quality of these food products. The total or partial replacement by other than the species declared on the product label in meat, milk or derived products compromises the nature and quality of these products, hurting consumer choice rights, which may be based on medical and nutritional recommendations, the economic value of the product or habits and/or dietary restrictions of each specific culture. Species identification in dairy and meat products is important in food traceability. Although food matrices are complex and variable, biomolecular techniques are gradually being applied for species identification, having proven increasingly reliable, fast, specific and highly sensitive, even in mixed samples. For these reasons, this review intends to show the main molecular methods applied to adulteration detection in dairy and meat derivatives, including an already established method, such as the polymerase chain reaction (PCR), as well as more advanced technologies, such as real-time PCR, next-generation DNA sequencing methods and DNA biochip or DNA microarray, which have been gradually applied to the detection and quantification of exogenous DNA in food samples, even if present in small amounts.
Показать больше [+] Меньше [-]Coatis (Nasua nasua) semen cryopreservation Полный текст
2015
Regina Celia Rodrigues da Paz | Heid Belle dos Santos Avila
Carnivore semen cryopreservation procedures started with semen washing and centrifuging in culture media for seminal plasma removal and microorganisms elimination. The objective of this study was to perform coatis semen cryopreservation comparing the effects between two extenders Ham’s F-10 and M199 for washing and centrifugation before cryopreservation using Dilutris medium. Semen samples (n = 36) were collected by electroejaculation from six adult male coatis (Nasua nasua) between May and October of 2008 at the Universidade Federal de Mato Grosso Zoo. Sperm total motility (%), progressive sperm motility (0-5), plasma membrane integrity spermatozoa rates (%), and acrosome integrity (%) were analyzed. These fresh semen samples were divided in two fractions, diluted in 1 ml of Ham’s F-10 (Ham’s F-10, Nutricel S.A., Brazil) or M199 (M199, Nutricel S.A., Brazil) and centrifuged at 300 g for 10 min. The supernatant was discarded and pellets resuspended in 1 ml of Dilutris (Dilutris, Minitube®, Brazil), stored at 5ºC for 3 hours, transferred to 0.25 ml straws, placed in liquid nitrogen vapor for 20 min, and immersed in liquid nitrogen. The means/SD for fresh semen and cryopreserved semen using Ham’s F-10/Dilutris and M199/Dilutris were, respectively: 84.28 ± 11.57, 45.38 ± 27.26, and 44.61 ± 25.03 for total motility; 3.64 ± 1.44, 2.15 ± 1.14, and 2.07 ± 1.03 for progressive sperm motility; 92.76 ± 3.46, 84.69 ± 15.77, and 89.76 ± 13.97 for live spermatozoa rate; and 94.76 ± 2.89, 92.35 ± 4.73, and 90.58 ± 7.17 for acrosome integrity. No significant difference (P < 0.05) were observed between the values obtained from the Ham’s F-10/Dilutris or M199/Dilutris treatments. Both treatments demonstrated to be suitable for freezing semen from this species.
Показать больше [+] Меньше [-]Use of serological diagnostic techniques in the control and eradication of caprine arthritis encephalitis: an update Полный текст
2015
Jamili Maria Suhet Mussi | Aurora Maria Guimarães Gouveia | Adriana Cortez | Andrey Pereira Lage | Alessandro de Sá Guimarães | Marcos Bryan Heinemann
Caprine arthritis encephalitis (CAE) is a chronic disease caused by a small ruminant lentivirus (SRLV), which causes significant losses in goat breeding. The actual state of animal infection with SRLV is difficult to determine due to a complex pathogenesis of the virus, including factors such as delayed or intermittent seroconversion in serological tests. Several serological techniques are available for disease diagnosis, such as screening or confirmation tests, which are different in sensitivity and specificity. Regarding the choice of the test to be applied, availability of commercial immunoreagents, team training, antigen used, and cost of techniques must be considered. This review presents the serological methods available for use in different stages of CAE control and eradication programs, and management measures to be adopted in conjunction with serological diagnosis of the disease.
Показать больше [+] Меньше [-]Sintomas mentais em homeopatia versus neurociência em medicina veterinária Полный текст
2015
Irvenia Luiza de Santis Prada | Marcela de Santis Prada
O objetivo deste estudo foi o de conhecer a devida correspondência entre os sintomas mentais considerados na homeopatia e as várias regiões e estruturas identificáveis no encéfalo dos animais. Os resultados obtidos mostraram que as sensações e emoções muito primitivas, como medos e fobias, interagem pontualmente com regiões evolutivamente também muito primitivas do cérebro (como amígdala e núcleos septais), enquanto sentimentos “nobres” como afeto e lealdade interagem holisticamente com várias estruturas cerebrais evolutivamente mais recentes, tais como as áreas neocorticais terciárias associativas (área pré-frontal e temporal). No primeiro caso, as manifestações orgânicas são mediadas pelo sistema nervoso autônomo com sinais fisiológicos de taquicardia, elevação da pressão arterial, vasoconstrição periférica, eriçamento de pelos, midríase e secreção de hormônios como adrenalina e cortisol (disfluência comportamental), enquanto na outra situação apontada, eventuais manifestações orgânicas são harmoniosas e serenas (fluência comportamental). O conteúdo de todo o texto do trabalho é indicativo do interesse prático dos dados obtidos para o clínico veterinário homeopata, ressaltando-se nesse contexto a validação do uso de repertórios homeopáticos humanos na clínica veterinária, evidentemente com as devidas precauções sempre balizadas pelo bom senso do profissional.
Показать больше [+] Меньше [-]Ocorrência de carrapatos em animais silvestres recebidos e atendidos pelo Parque Zoológico Municipal Quinzinho de Barros, Sorocaba, São Paulo, Brasil Полный текст
2015
Thiago Fernandes Martins | Rodrigo Hidalgo Friciello Teixeira | Marcelo Bahia Labruna
Os carrapatos são ectoparasitas da classe Arachnida que parasitam vertebrados terrestres, anfíbios, repteis, aves e mamíferos. O presente trabalho relata a ocorrência de carrapatos ixodídeos em animais silvestres recebidos e atendidos pelo Hospital Veterinário do Parque Zoológico Municipal Quinzinho de Barros, localizado no município de Sorocaba, estado de São Paulo, Brasil. De setembro de 1999 a maio de 2015, foram coletados carrapatos em animais silvestres da região de Sorocaba e de outros 20 municípios do interior do estado de São Paulo. Ao todo, foram identificados 43 larvas, 637 ninfas e 1.178 adultos (631 machos e 547 fêmeas), totalizando 1.858 exemplares de 14 espécies distintas de ixodídeos. Durante exames clínicos de rotina, foram inspecionadas duas espécies de repteis, uma espécie de ave e 11 espécies distintas de mamíferos de um total de 103 animais silvestres amostrados. Nos repteis foram identificados Amblyomma rotundatum, nas aves Amblyomma sculptum e nos mamíferos Amblyomma aureolatum, Amblyomma brasiliense, Amblyomma calcaratum, Amblyomma dubitatum, Amblyomma longirostre, Amblyomma nodosum, Amblyomma ovale, A. sculptum, Amblyomma varium, Ixodes aragaoi, Haemaphysalis juxtakochi, Rhipicephalus microplus e Dermacentor nitens. Este estudo relata os primeiros registros de fêmeas de A. rotundatum parasitando Hydromedusa tectifera e Oxyrhopus guibei, assim como ninfas de A. dubitatum e H. juxtakochi em Chrysocyon brachyurus, ninfas de A. brasiliense em Myrmecophaga tridactyla e Tamandua tetradactyla, além de ninfas de A. sculptum em Alouatta guariba e Sphiggurus villosus no país, demonstrando que os zoológicos são uma fonte de informação valiosa para o conhecimento parasitológico da fauna silvestre brasileira.
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