Aspectos morfométricos do timo em gatos domésticos (Felis domesticus)

O timo é um órgão linfático primário que desenvolve sua atividade em organismos jovens. Apesar de sua função ser responsável por mecanismos fundamentais na aquisição das defesas e conseqüentes respostas orgânicas, ela ainda não está totalmente esclarecida, nem tampouco as bases morfológicas que respondem por tais funções, como o processo de desenvolvimento e involução do órgão. Objetivou-se analisar e caracterizar os aspectos morfológicos do timo, tais como seu tamanho e volume, e aspectos histológicos do timo em gatos, correlacionando o sexo e o desenvolvimento etário. Doze timos provenientes de fetos de gatos domésticos (Felis domesticus) sem raça definida (SRD), machos e fêmeas, separados em três grupos etários. O timo apresentou-se com uma coloração rosa-pálida e com duas porções, a torácica e a cervical, sendo que cada uma delas possuía um lobo direito e um lobo esquerdo em sua maioria. A porção torácica localizava-se em região de mediastino cranial, entre os pulmões e à base do coração. E a porção cervical estendia-se além das costelas em sentido cranial, estando localizada ventralmente à traqueia. A estrutura celular do timo demonstrou-se organizada com a presença de agregados concêntricos, os chamados corpúsculos tímicos, formados por células epiteliais, sustentada por uma cápsula de tecido conjuntivo de onde partiam septos que ao penetrar no órgão dividia-o em lóbulos. Ocorreram variações significativas quanto à lobação e as dimensões do timo entre indivíduos da mesma faixa etária, e entre sexos diferentes. Os valores relativos ao comprimento, espessura e largura, de maneira geral, apresentaram aumento, em conformidade ao desenvolvimento dos animais, mas com diferenças entre os sexos.

Serotyping of Toxoplasma gondii in cats (Felis domesticus) reveals predominance of type II infections in Germany.

BACKGROUND Cats are definitive hosts of Toxoplasma gondii and play an essential role in the epidemiology of this parasite. The study aims at clarifying whether cats are able to develop specific antibodies against different clonal types of T. gondii and to determine by serotyping the T. gondii clonal types prevailing in cats as intermediate hosts in Germany. METHODOLOGY To establish a peptide-microarray serotyping test, we identified 24 suitable peptides using serological T. gondii positive (n=21) and negative cat sera (n=52). To determine the clonal type-specific antibody response of cats in Germany, 86 field sera from T. gondii seropositive naturally infected cats were tested. In addition, we analyzed the antibody response in cats experimentally infected with non-canonical T. gondii types (n=7). FINDINGS Positive cat reference sera reacted predominantly with peptides harbouring amino acid sequences specific for the clonal T. gondii type the cats were infected with. When the array was applied to field sera from Germany, 98.8% (85/86) of naturally-infected cats recognized similar peptide patterns as T. gondii type II reference sera and showed the strongest reaction intensities with clonal type II-specific peptides. In addition, naturally infected cats recognized type II-specific peptides significantly more frequently than peptides of other type-specificities. Cats infected with non-canonical types showed the strongest reactivity with peptides presenting amino-acid sequences specific for both, type I and type III. CONCLUSIONS Cats are able to mount a clonal type-specific antibody response against T. gondii. Serotyping revealed for most seropositive field sera patterns resembling those observed after clonal type II-T. gondii infection. This finding is in accord with our previous results on the occurrence of T. gondii clonal types in oocysts shed by cats in Germany.

Ocorrência de infecções por Babesia spp. e Hepatozoon spp. em gatos domésticos (Felis domesticus) do Estado de São Paulo e do Distrito Federal

Pós-graduação em Medicina Veterinária - FMVZ

Células-tronco localizadas na cinta placentária de carnívoros domésticos (Canis familiaris e Felis domesticus)

As células-tronco podem ser isoladas tanto de tecidos embrionários quanto de tecidos provenientes de um organismo adulto. Este projeto teve por objetivo caracterizar, descrever as células derivadas da região uterina e da cinta placentária junção materno/fetal da placenta de carnívoros domésticos (cães e gatos), e verificar a sua capacidade de pluripotência. Os úteros gestantes e não gestantes foram obtidos em campanhas de castrações e de controle populacional de cães e gatos, na cidade de Pirassununga/SP. Foram coletados 24 úteros gravídicos de animais hígidos, em diferentes idades gestacionais. O material foi dividido em três fases distintas da gestação, ou seja inicio que compreende de 8 a 20 dias de gestação; meio de 21 a 30 dias de gestação e final de 31 a 60 dias de gestação. O material foi coletado de fêmeas caninas e felinas, quatro úteros de cada fase, totalizando 12 úteros de cães e 12 de felinos. Coletamos também 8 úteros de fêmeas nulíparas (4 de cadelas e 4 de gatas) e 8 úteros com um mês pós parto (4 de cadelas e 4 de gatas). As amostras foram fixadas em paraformoldeido tamponado a 4% para a análise histológica e de imunohistoquimica. Para a padronização da imunohistoquimica inúmeros testes de marcação e diluição dos anticorpos utilizados nesta pesquisa foram realizados, todo protocolo aqui descrito foi padronizado pela primeira vez. Nas análises de imunohistoquimica avaliamos a expressão de marcadores associados a células-tronco pluripotentes Nanog, Oct4 e Sox2. Nas cadelas, as marcações foram positivas em todas as fases, gestacionais e não gestacionais. A detecção dessas proteínas nesta espécie ficaram padronizadas, destacando algumas diferenças quantitativas durante alguns períodos da gestação. Foi observado que o Oct4 na cadela, mostra uma diferença significativa (p=0,0064), entre as fases de início e meio da gestação e entra o início e a fase de termo. Quando comparados os resultados das análises imunohistoquimicas utilizando os três anticorpos entre si, nos três períodos gestacionais ficou evidente uma diferença (p=0,0005) somente relativa a proteína Nanog com Oct4. Nas gatas apenas foi possível padronizar o protocolo do Nanog e do Sox2, sendo a marcação feita com Oct4 negativa. Nesta espécie foi possível observar uma diferença da proteína Nanog (p=0,0006) quando comparada na fase inicial para a fase do meio e início da gestação para a fase termo. No que se refere as fêmeas nulíparas e fêmeas pós-parto destaca-se a ausência de diferenças quando comparados os anticorpos na fase pós parto tanto em cadelas quanto em gatas. Na fase nulípara foram observadas diferenças somente na cadela (p=0,0018) para os três anticorpos. Desta forma, a caracterização de células de origem placentária com característica de células tronco pode abrir um leque de possibilidades para obtenção destas células de forma mais ética, uma vez que este material é descartado na castrações. Foi possível a identificação das células que expressão proteínas pluripotentes em diferentes idades gestacionais, tanto na região de cinta placentária como no útero. Apesar de semelhantes, as espécies aqui estudadas apresentaram diferenças na realização do protocolo da imunihistoquímica. Pesquisas relacionadas com as células-tronco do endométrio vêm crescendo, principalmente porque estas células podem ser facilmente obtidas, a partir de fontes descartadas, sem entraves éticos. Desta forma tem o potencial de serem uma nova fonte para o desenvolvimento na terapêutica como terapia celular

Sensitization to indoor aeroallergens in children who attended the Allergy Service of the “Dr. José Eleuterio González” University Hospital of Monterrey, Mexico

Background: Indoor aeroallergens are the main cause of sensitization in children and represent a risk factor for the development of allergic diseases. Objective: Identify the major indoor aeroallergens most often sensitized to pediatric patients treated at the Allergy Service at the “Dr. José Eleuterio González” University Hospital of Monterrey Methods: We performed an observational and descriptive study where we reviewed reports of positive skin tests to the following common indoor aeroallergens: Dermatophagoides farinae (D. farinae), Dermatophagoides pteronyssinus (D. pteronyssinus), Canis familiaris (C. familiaris), Felis domesticus (F. domesticus), Blattella germanica (B. germanica) and Periplaneta americana (P. americana), found in patients under 16 years with symptoms of allergy, during the period of 2011-2012. Results: We performed 439 skin tests to aeroallergens in pediatric patients. Of these, 57.6% were male and 42.4% were female. Mean age was 6.3 years. The age groups were under 3 years: 17.8%, 3-5 years: 35%, 6-12 years: 36%, and 13-16 years: 11.2%. The main diagnoses were: allergic rhinitis (71.8%), asthma (16.6%), and atopic dermatitis (4.3%). In 57.9% of the cases, they had at least one positive skin test to any aeroallergen. The rate of sensitization to speciic aeroallergens was: D. Pteronyssinus 49.0%, D. farinae 44.6%, B. germanica 13.9%, P. Americana 10.9%, F. domesticus 10.7%, and C. familiaris 5.9%. Conclusion: Indoor aeroallergen sensitization can occur early in life, although it was more frequent in the preschooler and elementary school group. Dust house mites were the most commom cause of allergic sensitization.

Avaliação mesoscópica da origem, distribuição e ramificação do nervo radial no braço do gato doméstico (Felis catus domesticus, Linnaeus, 1758)

The present study evaluated the origin, distribution and ramification of the radial nerves were studied in 30 adult domestic cats. The sample included 15 females and 15 males of unknown breed. The specimens were fixed in 10% formaldehyde solution. The radial nerve showed many fascicles from the origin also your ramification in superficial and deep branches. Radial nerves were observed to originate, in 16 cases (26.7%), from the ventral branch of the sixth cervical spinal nerve; in 60 cases (100%), from the ventral branch of the seventh cervical spinal nerve; in 60 cases (100%), from the ventral branch of the eight cervical nerve and in 60 cases (100%), from the ventral branch of the first thoracic nerve. The radial nerves branched out, in all of the animals studied (100.0%), to the tensor fasciae antebrachii, long, accessory, medial and lateral heads of the triceps branchii and anconeus muscles. The radial nerve emits of 14 to 25 nervous branches in this region. However, the branch of the sixth cervical spinal nerve and the nervous fascicles reveal significant differences (p <= 0.05), respectively, in or with relation to sex of the animals and the studied region.

Anatomicosurgical arterial segmentation of the cat lungs (Felis catus domesticus, L., 1758)

O objetivo desta pesquisa foi estabelecer os segmentos anátomo-cirúrgicos arteriais, através da lobação e ramificação intralobar arterial, em pulmões de gato. Após a dissecção de vinte pulmões, notou-se que a artéria pulmonar direita geralmente emite um ramo para o lobo cranial e um ramo para o lobo médio, sendo originados juntos em um tronco. Um grande ramo irriga o lobo caudal na maioria dos casos. Dois ramos com origem comum no ramo arterial do lobo caudal irrigam o lobo acessório. A artéria pulmonar esquerda origina um tronco que, na maioria dos casos, emite um ramo para a porção cranial e um ramo para a porção caudal do lobo cranial esquerdo. Pode-se concluir que o pulmão direito é formado por quatro e o esquerdo por dois lobos, ocorrendo variações na ramificação arterial pulmonar.

Anatomia do músculo abdutor crural caudal do gato doméstico (Felis catus domesticus, Linnaeus 1758)

The frequency and the morphology of the abductor cruris caudalis muscle were studied in 58 adult unknown breed cats. The sample included 36 females and 22 males. After the dissection, were found a frequency for the presence of the same muscle of 98.3%. The abductor cruris caudalis muscle appears symmetrically in 35 females (97.2%) and 22 males (100.0%). When present, it were originated on the transversal process of the 1st vertebrae caudales, in the glutea region, below the gluteus superficialis muscle, throughing almost all the thigh under biceps femoris muscle, where it make a parallel relation with the sciatic nerve, receiving nervous ramifications of the same in 78.3% of the cases. The medium found for the width and thickness of his muscle venter was respectively of 2.03 mm and 0.35 mm. Its insertion occurs on the biceps femoris muscles approximate to the fascia cruris, where both finish fusing theirselves.

Origem, ramificação e distribuição fascicular do nervo radial no braço do gato doméstico (Felis catus domesticus, Linnaeus, 1758)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estimated Number of Birds Killed by House Cats (Felis catus) in Canada

Predation by house cats (Felis catus) is one of the largest human-related sources of mortality for wild birds in the United States and elsewhere, and has been implicated in extinctions and population declines of several species. However, relatively little is known about this topic in Canada. The objectives of this study were to provide plausible estimates for the number of birds killed by house cats in Canada, identify information that would help improve those estimates, and identify species potentially vulnerable to population impacts. In total, cats are estimated to kill between 100 and 350 million birds per year in Canada (> 95% of estimates were in this range), with the majority likely to be killed by feral cats. This range of estimates is based on surveys indicating that Canadians own about 8.5 million pet cats, a rough approximation of 1.4 to 4.2 million feral cats, and literature values of predation rates from studies conducted elsewhere. Reliability of the total kill estimate would be improved most by better knowledge of feral cat numbers and diet in Canada, though any data on birds killed by cats in Canada would be helpful. These estimates suggest that 2-7% of birds in southern Canada are killed by cats per year. Even at the low end, predation by house cats is probably the largest human-related source of bird mortality in Canada. Many species of birds are potentially vulnerable to at least local population impacts in southern Canada, by virtue of nesting or feeding on or near ground level, and habitat choices that bring them into contact with human-dominated landscapes where cats are abundant. Because cat predation is likely to remain a primary source of bird mortality in Canada for some time, this issue needs more scientific attention in Canada.

Cats about town: is predation by free-ranging pet cats Felis catus likely to affect urban bird populations?

Even though they are fed daily by their owners, free-ranging pet cats Felis catus may kill wild birds and, given their high densities (typically > 200 cats/km(2)), it has been postulated that cat predation could be a significant negative factor affecting the dynamics of urban bird populations. In this study, we: (1) used questionnaire surveys in 10 sites within the city of Bristol, UK, to estimate cat density; (2) estimated the number of birds killed annually in five sites by asking cat owners to record prey animals returned home; and then (3) compared the number of birds killed with breeding density and productivity to estimate the potential impact of cat predation. In addition, we (4) compared the condition of those birds killed by cats versus those killed in collisions, e.g. window strikes. Mean (+/- sd) cat density was 348 +/- 86 cats/km(2) (n = 10 sites); considering the eight species most commonly taken by cats, the mean ratios of adult birds/cats and juvenile birds/cats across the five sites were 1.17 +/- 0.23 and 3.07 +/- 0.74, respectively. Approximately 60% of the cats studied for up to 1 year at each site never returned any prey home; despite this, the estimated number of birds killed was large relative to their breeding density and productivity in many sites. Across species, cat-killed birds were in significantly poorer condition than those killed following collisions; this is consistent with the notion that cat predation represents a compensatory rather than additive form of mortality. Interpretation of these results is, however, complicated by patterns of body mass regulation in passerines. The predation rates estimated in this study would suggest that cats were likely to have been a major cause of mortality for some species of birds. The effect of cat predation in urban landscapes therefore warrants further investigation. The potential limitations of the current study are discussed, along with suggestions for resolving them.

Spatio-temporal variation in predation by urban domestic cats (Felis catus) and the acceptability of possible management actions in the UK

Urban domestic cat (Felis catus) populations can attain exceedingly high densities and are not limited by natural prey availability. This has generated concerns that they may negatively affect prey populations, leading to calls for management. We enlisted cat-owners to record prey returned home to estimate patterns of predation by free-roaming pets in different localities within the town of Reading, UK and questionnaire surveys were used to quantify attitudes to different possible management strategies. Prey return rates were highly variable: only 20% of cats returned ≥4 dead prey annually. Consequently, approximately 65% of owners received no prey in a given season, but this declined to 22% after eight seasons. The estimated mean predation rate was 18.3 prey cat−1 year−1 but this varied markedly both spatially and temporally: per capita predation rates declined with increasing cat density. Comparisons with estimates of the density of six common bird prey species indicated that cats killed numbers equivalent to adult density on c. 39% of occasions. Population modeling studies suggest that such predation rates could significantly reduce the size of local bird populations for common urban species. Conversely, most urban residents did not consider cat predation to be a significant problem. Collar-mounted anti-predation devices were the only management action acceptable to the majority of urban residents (65%), but were less acceptable to cat-owners because of perceived risks to their pets; only 24% of cats were fitted with such devices. Overall, cat predation did appear to be of sufficient magnitude to affect some prey populations, although further investigation of some key aspects of cat predation is warranted. Management of the predation behavior of urban cat populations in the UK is likely to be challenging and achieving this would require considerable engagement with cat owners.

Molecular detection of Leishmania sp. in cats (Felis catus) from Andradina Municipality, São Paulo State, Brazil

The aim of this work was to molecularly detect Leishmania species in 52 cats from Andradina Municipality, São Paulo State, Brazil. The direct parasitological test was performed by using imprints of poplited lymph node, bone marrow and spleen to verify amastigote forms of Leishmania spp. The samples that were positive parasitological tests were subjected to molecular analysis (PCR) and sequencing. Infection was detected for 5.76% (3/52) of the examined cats and two had presence of amastigote forms of Leishmania spp. in lymph nodes. Polymerase chain reaction (PCR) of kinetoplast minicircle DNA, indicated positive amplification for samples of spleen and lymph nodes and the sequencing resulted in 97% similarity with Leishmania (L) chagasi. This study proved the occurrence of infection with Leishmania (L) chagasi in felines from Andradina municipality, São Paulo State. (C) 2010 Elsevier B.V. All rights reserved.