How the neural representations of different sensory modalities transition from one to another is an unexplored issue of cortical organization. The present experiments addressed this problem by examining auditory projections to the lateral suprasylvian visual area (LSS) of the cat using neuroanatomical tract tracing methods. Injections of tracer (Biotinylated Dextran Amine, BDA) were made into defined areas of the cat auditory cortex. Following transport and tissue processing, a light microscope with a digitizing stage was used to visualize and plot labeled auditory projections to the LSS. The results showed that all auditory cortices tested demonstrated projections to a restricted portion of the LSS. While these projections were concentrated on the outer lip of the lateral bank of the LSS, some scattered auditory projections were found along the entire depth of the lateral bank. These data indicate that, at least in the LSS, projections from different sensory modalities do not form abrupt borders but exhibit areas of overlap. These overlapped projections may provide the anatomical basis for multisensory properties of neurons within transition areas between representations of different sensory modalities.

Este trabalho foi realizado com o escopo de determinar a ocorrência de infecção leptospirótica em gatos, utilizando-se tanto da pesquisa de anticorpos específicos como de tentativas de isolamento e demonstração do agente a partir de fragmentos de rins destes espécimen. Visou-se, também, estudar aspectos clínico-laboratoriais, bacteriológicos e epidemiológicos da leptospirose felina, pela inoculação de gatos adultos com cepas autóctones, patogênicas, de L interrogans. Utilizando-se da reação de soroaglutinação microscópica, tendo como antígenos 18 sorotipos representativos de 17 sorogrupos de Leptospira, obteve-se, dentre as 172 amostras séricas examinadas, 22 sororeagentes (12,8 por cento ), com título >= 100. A maior frequência de soropositividade demonstrada foi para o sorotipo pomona. Não se observaram diferenças estatisticamente significantes (ao nível de = 0,05) com relação ao sexo, todavia, através da análise estatística (ao nível de = 0,05, demonstrou-se que a frequência da infecção é maior nos felinos adultos. Nas 172 amostras de pares de rins submetidas à cultura em meio de Fletcher, não se obteve êxito no isolamento do agente. Ademais, não se demonstrou a presença de leptospira em cortes de rins dos animais sororeagentes através da impregnação argêntica, segundo a técnica de Warthin-Starry. Após a inoculação, por via subcutânea, de 5 animais com cepa do sorotipo icteroharmorrhagiae (R-192) e de outros 5 com cepa do sorotipo canicola (CCZ-8), estes gatos ficaram sob observação durante um per1odo de 8 a 12 semanas. Em nenhum deles se manifestou qualquer alteração do estado de higidez, do quadro hemático e nos exames de urina realizados. Foram detectadas aglutininas antileptospira em 90 por cento dos animais inoculados, entre a 1ª e a 6ª semanas a contar da inoculação. Dos 9 animais que se soroconverteram, 8 permaneceram soropositivos durante 8 a 12 semanas. Apenas os animais inoculados com o sorotipo canicola eliminaram leptospiras pela urina, iniciando-se a leptospirúria entre a 2a e 4a semanas da inoculação e as sim persistinto por 2 a 8 semanas. Não se obteve nenhuma hemocultura ou nefrocultura positiva e nem se pôde demonstrar a presença de leptospiras no parênquina renal dos 10 anmais inoculados. / The occurrence of leptospiral infection in cats was determined through the detection of specific antibodies based on the results of microscopic agglutination test and the attempts of isolation and histological demonstration of leptospires from the kidneys of these animals. Clinical, laboratorial and epidemiological aspects of experimental feline leptospirosis were also studied; for this purpose, adult cats were inoculated with patogenic autochthonal strains of Leptospira interrogans. Of 172 serum samples examined by microscopic agglutination test, 22 (12,8 per cent ) were positive with titers >= 100. The most frequent serovar was pomona. In relation to the sex, statistical significant differences (level of ~ = O, 05) were not seen; however the age distribution showed that feline leptospirosis is more frequent in adult cats. The attempts for isolation and de monstration of L· interrogans from renal parenchyma either by culture or Warthin-Starry technics were unsuccessfull. Ten adult cats of mixed breed and both sexes were used for experimental infection. Five animals were inoculated subcutaneously, with serovar icterohaemorrhagiae (R-192) and other five with serovar canicola (CCZ-8) by the same route. The clinical and laboratorial findings presented no alterations in the inoculated animals. Antileptospiral agglutinins were detected in 90 per cent of the infected cats between 1st and 6th week after inoculation. From 9 cats with leptospiral agglutinins, 8 persisted seropositive for 8 to 12 weeks. The elimination of leptospires through urine was observed only in the animals infected with serovar canicola, begining 2 to 4 weeks after inoculation and lasting for 2 to 8 weeks. The hemoculture as well the kidney cultures from inoculated cats were also unsuccessfull.

Este trabalho foi realizado com o escopo de determinar a ocorrência de infecção leptospirótica em gatos, utilizando-se tanto da pesquisa de anticorpos específicos como de tentativas de isolamento e demonstração do agente a partir de fragmentos de rins destes espécimen. Visou-se, também, estudar aspectos clínico-laboratoriais, bacteriológicos e epidemiológicos da leptospirose felina, pela inoculação de gatos adultos com cepas autóctones, patogênicas, de L interrogans. Utilizando-se da reação de soroaglutinação microscópica, tendo como antígenos 18 sorotipos representativos de 17 sorogrupos de Leptospira, obteve-se, dentre as 172 amostras séricas examinadas, 22 sororeagentes (12,8 por cento ), com título >= 100. A maior frequência de soropositividade demonstrada foi para o sorotipo pomona. Não se observaram diferenças estatisticamente significantes (ao nível de = 0,05) com relação ao sexo, todavia, através da análise estatística (ao nível de = 0,05, demonstrou-se que a frequência da infecção é maior nos felinos adultos. Nas 172 amostras de pares de rins submetidas à cultura em meio de Fletcher, não se obteve êxito no isolamento do agente. Ademais, não se demonstrou a presença de leptospira em cortes de rins dos animais sororeagentes através da impregnação argêntica, segundo a técnica de Warthin-Starry. Após a inoculação, por via subcutânea, de 5 animais com cepa do sorotipo icteroharmorrhagiae (R-192) e de outros 5 com cepa do sorotipo canicola (CCZ-8), estes gatos ficaram sob observação durante um per1odo de 8 a 12 semanas. Em nenhum deles se manifestou qualquer alteração do estado de higidez, do quadro hemático e nos exames de urina realizados. Foram detectadas aglutininas antileptospira em 90 por cento dos animais inoculados, entre a 1ª e a 6ª semanas a contar da inoculação. Dos 9 animais que se soroconverteram, 8 permaneceram soropositivos durante 8 a 12 semanas. Apenas os animais inoculados com o sorotipo canicola eliminaram leptospiras pela urina, iniciando-se a leptospirúria entre a 2a e 4a semanas da inoculação e as sim persistinto por 2 a 8 semanas. Não se obteve nenhuma hemocultura ou nefrocultura positiva e nem se pôde demonstrar a presença de leptospiras no parênquina renal dos 10 anmais inoculados. / The occurrence of leptospiral infection in cats was determined through the detection of specific antibodies based on the results of microscopic agglutination test and the attempts of isolation and histological demonstration of leptospires from the kidneys of these animals. Clinical, laboratorial and epidemiological aspects of experimental feline leptospirosis were also studied; for this purpose, adult cats were inoculated with patogenic autochthonal strains of Leptospira interrogans. Of 172 serum samples examined by microscopic agglutination test, 22 (12,8 per cent ) were positive with titers >= 100. The most frequent serovar was pomona. In relation to the sex, statistical significant differences (level of ~ = O, 05) were not seen; however the age distribution showed that feline leptospirosis is more frequent in adult cats. The attempts for isolation and de monstration of L· interrogans from renal parenchyma either by culture or Warthin-Starry technics were unsuccessfull. Ten adult cats of mixed breed and both sexes were used for experimental infection. Five animals were inoculated subcutaneously, with serovar icterohaemorrhagiae (R-192) and other five with serovar canicola (CCZ-8) by the same route. The clinical and laboratorial findings presented no alterations in the inoculated animals. Antileptospiral agglutinins were detected in 90 per cent of the infected cats between 1st and 6th week after inoculation. From 9 cats with leptospiral agglutinins, 8 persisted seropositive for 8 to 12 weeks. The elimination of leptospires through urine was observed only in the animals infected with serovar canicola, begining 2 to 4 weeks after inoculation and lasting for 2 to 8 weeks. The hemoculture as well the kidney cultures from inoculated cats were also unsuccessfull.

O coronavírus felino (FCoV) ocorre sob uma grande diversidade gênica de amostras e é classificado em dois patotipos: o coronavírus felino entérico (FECoV) e o vírus da peritonite infecciosa felina (FIPV). O patotipo FIPV é altamente virulento e responsável pelo desenvolvimento de uma doença altamente fatal, denominada de peritonite infecciosa felina (PIF). Já o FECoV apresenta-se amplamente disseminado na população felina e é responsável na maioria das vezes por infecção assintomática. Atualmente, nenhum marcador gênico conhecido é capaz de diferenciar os patotipos FECoV de FIPV. O presente estudo foi dividido em dois capítulos. No primeiro capítulo, objetivou-se avaliar a diversidade molecular do gene da membrana (M) em 190 amostras provenientes de 5 gatos sem manifestações de PIF (PIF-) e de 10 gatos com manifestações clínicas e histopatológicas de PIF (PIF+). Com esse estudo, conclui-se que tanto a hipótese de mutação in vivo do FECoV para FIPV, quanto a hipótese de transmissão entre gatos do patotipo FIPV são plausíveis. No segundo capítulo, com o objetivo de avaliar a diversidade dos genes 3a-c, E e M foram sequenciados clones de amplicons para estes genes obtidos, de 6 gatos PIF+ e 2 gatos PIF-. Os genes 3a-c, E e M apresentaram diversidade gênica que confere a constituição das quasiespécies de coronavírus felino com probabilidade de emergência do patotipo de alta virulência, mas de um modo hospedeiro-específico. Com o segundo estudo, conclui-se que as linhagens FIPV de coronavírus felino apresentaram a proteína 3c truncada, sendo o gene 3c o único marcador de patotipo dos FCoVs observado dentre os genes estudados. / Feline coronavirus (FCoV) occurs as a large genic diversity of strains and is classified as two pathotypes: feline enteric coronavirus (FECoV) and feline infectious peritonitis virus (FIPV). The FIPV pathotype is highly virulent and responsible for the onset of a highly fatal disease named feline infectious peritonitis (FIP), while the FECoV pathotype is widely disseminated in feline populations leading mostly to asymptomatic infections. No genic marker is currently known to differentiate the FECoV and FIPV pathotypes. This study has been divided in two chapters. In the first chapter, the aim was to evaluate the molecular diversity of the membrane (M) gene in 190 samples from 5 cats without FIP (FIP-) and 10 cats with clinical and histopathological evidence of FIP (FIP+). The conclusion of this study is that both the in vivo mutation hypothesis in the FECoV-to-FIP direction and the hypothesis of FIPV transmission amongst cats are plausible. In the second chapter, aimed to evaluate the diversity of genes 3a-c, E and M, clones of amplicons for these genes were obtained and sequenced from samples from six FIP+ and 2 FIP- cats. Genes 3a-c, E and M show a genic diversity that results in a quasispecies constitution of FCoV that leads to the probability of the emergence of the highly virulent pathotype in a host-specific way. The conclusion of this second study is that FIPV lineages show a truncated form of the 3C protein, making the 3c gene the only pathotype marker for FCoV observed amongst the genes studied herein.

Feline leukemia viruses (FeLVs) are pathogenic retroviruses of the domestic cat. FeLV transmission and emergence of pathogenic variants show striking similarity to HIV pathogenesis. The emergence of pathogenic subgroup-C FeLV from the transmitted subgroup-A FeLV coincides with a switch in host receptor used for infection as a result of mutations in the viral envelope protein (Env). I have characterized a novel FeLV Env that may represent an evolutionary intermediate between FeLV-A and FeLV-C. I have also reported evidence suggesting that FeLVs may use co-factors/co-receptors for infection. I have found that FeLVs inefficiently infect murine NIH3T3 cells overexpressing FeLV receptors (NIH3T3/Receptor). I have provided evidence that the low infection is caused by a block at a post-binding but pre-entry stage of FeLV infection. Furthermore, fusion of NIH3T3/Receptor cells with highly susceptible cells rescues inhibition to infection suggesting that FeLVs, like HIV, may also use co-receptors for infection.

Feline leukemia viruses (FeLVs) are pathogenic retroviruses of the domestic cat. FeLV transmission and emergence of pathogenic variants show striking similarity to HIV pathogenesis. The emergence of pathogenic subgroup-C FeLV from the transmitted subgroup-A FeLV coincides with a switch in host receptor used for infection as a result of mutations in the viral envelope protein (Env). I have characterized a novel FeLV Env that may represent an evolutionary intermediate between FeLV-A and FeLV-C. I have also reported evidence suggesting that FeLVs may use co-factors/co-receptors for infection. I have found that FeLVs inefficiently infect murine NIH3T3 cells overexpressing FeLV receptors (NIH3T3/Receptor). I have provided evidence that the low infection is caused by a block at a post-binding but pre-entry stage of FeLV infection. Furthermore, fusion of NIH3T3/Receptor cells with highly susceptible cells rescues inhibition to infection suggesting that FeLVs, like HIV, may also use co-receptors for infection.

Serum lipase activity has traditionally been used for diagnosis of pancreatitis in human beings and dogs. However, serum lipase activity is not specific for exocrine pancreatic function and many cell types other than pancreatic acinar cells also synthesize lipases. Recently, an immunoassay for the measurement of canine pancreatic lipase immunoreactivity has been developed and validated. This assay has shown to be specific for exocrine pancreatic function and sensitive for the diagnosis of canine pancreatitis. The objectives of this project were to purify feline pancreatic lipase (fPL), have antibodies against fPL (anti-fPL antibodies) produced, and develop a radioimmunoassay (RIA) for the diagnosis of feline pancreatitis. Pancreatic lipase was purified from feline pancreatic tissue by delipidation, anion-exchange chromatography, size-exclusion chromatography, and cation-exchange chromatography. Antiserum against fPL was raised in rabbits. Tracer was produced by iodination (125I) of fPL using the chloramine T method. An RIA was established and validated by determination of sensitivity, dilutional parallelism, spiking recovery, intraassay variability, and inter-assay variability. A control range for fPLI in cat serum was established from 30 clinically healthy cats using the central 95th percentile. The sensitivity of the fPLI assay was 1.2 μg/L. Observed to expected ratios for serial dilutions ranged from 58.0 to 164.3% for 4 different serum samples at dilutions of 1 in 2, 1 in 4, and 1 in 8. Observed to expected ratios for spiking recovery ranged from 76.0 to 156.5% for 4 different serum samples and 6 different spiking concentrations. Coefficients of variation for intra-assay variability for 4 different serum samples were 10.1, 4.5, 2.2, and 3.9%. Coefficients of variation for inter-assay variability for 4 different serum samples were 24.4, 15.8, 16.6, and 21.3%. The control range for serum fPLI concentration was established as 1.2 to 3.8 μg/L. All of the objectives outlined above were successfully met, leading to the development of an RIA for the measurement of fPLI in cat serum. The RIA for fPLI described here is sufficiently accurate and precise, but has a limited linearity and reproducibility in the lower and higher end of the working range.

Zugl.: Giessen, Universiẗat, Diss., 2009.

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xiv, 144 p.; also includes graphics (some col.). Includes abstract and vita. Co-advisors: Lawrence E. Mathes and Maria H. Neff, Dept. of Veterinary Biosciences. Includes bibliographical references (p. 122-144).

Obesity is the most prevalent nutritional disorder in cats (Felis catus; Hoenig et al., 2011). High carbohydrate diets, prescribed for weight loss, may contribute to adiposity (Thiess et al., 2004). The effects of a high fat (HF; 30% fat, 10% carbohydrate), high carbohydrate (HC; 10% fat, 46% carbohydrate) and a moderate diet (15% fat, 30% carbohydrate) supplemented with a calorie restriction mimetic (mannoheptulose (MH); 8 mg/kg BW), fed to energy requirements, on feline metabolism and behaviour were investigated (n=20; 4 ± 2.5 kg). An 11 week acclimation procedure was designed to adapt cats to 24-hr restriction within a chamber used for indirect calorimetry. Stress indicative behaviour (Kessler and Turner, 1997) declined with repreated exposure to increasing lengths of restriction within chambers and on week 11 stress levels were low and consistent (P<0.05). Neither the HF nor HC diet impacted body weight (p>0.05); however, HF feeding caused an increase in body fat (0.75 kg (baseline) vs. 1 kg (86d)) after long-term feeding. Energy expenditure (EE) was not impacted by dietary fat/carbohydrate. Respiratory quotients (RQ) increased and decreased with exposure to the HC (fasted= 0.80 ± 0.008; fed= 0.87 ± 0.008), HF (fasted= 0.76 ± 0.008; fed= 0.78 ± 0.008) diet, respectively. Glucose to insulin (G:I) ratio increased with HF feeding; indicating improved insulin sensitivity. Physical activity, measured using accelerometers, declined with HF (-1.6 counts/hr) and HC (-2.8 counts/hr) feeding from baseline. T-maze performance decreased and increased with HF (-0.85 score/10) and HC (0.85 score/10) feeding from baseline (p<0.05). MH did not impact body weight or composition (p>0.05). Area under the curve for EE increased during the 15-22 hour post feeding with MH treatment (2370.3 (-MH) vs. 3292.0 (+MH) ± 0.0002). RQ and G:I were not impacted by MH (p>0.05). MH increased play motivation, measured using obstruction tests (p<0.05). Diets high in carbohydrate are not ideal for weight loss since they negatively impact insulin sensitivity and voluntary EE. Diets promoting elevated EE, activity and normal glucose/insulin profiles are ideal for weight control and MH offers a unique opportunity for use in weight loss regimes. / This work was funded by Procter and Gamble Co.