Master of Science / Department of Animal Sciences and Industry / James S. Drouillard / Since the 1960’s liver abscess incidence and severity have been identified as a problem associated with feeding high concentrate finishing rations to feedlot cattle. Liver abscesses lead to decreased feedlot performance and decreased carcass value. Tylosin phosphate is a macrolide antibiotic commonly used by feedlots throughout the United States and has been shown to successfully control liver abscesses. In 2013, the FDA issued Guidance for Industry #213, which encourages reduced usage of medically important classes of antibiotics, such as macrolides, in animal feed. This will be achieved by implementing veterinary oversight of these drugs via Veterinary Feed Directives (VFD). Thus, it is of importance to find alternative strategies to reduce usage of tylosin in finishing rations to control liver abscesses. One strategy that has been suggested is increasing dietary roughage concentration. However, this isn’t a viable option as increasing dietary roughage concentration not only leads to a decline in feedlot performance, hot carcass weight, and dressing percentage, but also has an environmental impact. Available research has also indicated that increasing dietary roughage has no impact on liver abscess incidence or severity. Our research objective was therefore to identify alternative strategies to reduce liver abscess incidence. Our first trial evaluated the impact of antioxidants on liver abscess incidence and severity. Treatments consisted of a control treatment (basal diet containing 200 IU/d α-tocopherol acetate), and an antioxidant treatment (basal diet containing 2000 IU/d α-tocopherol acetate and 500 mg/d crystalline ascorbate). Treatments were randomly assigned to 390 crossbred heifers. No differences in feedlot performance were detected; however, there was a tendency for improved feed intake (P = 0.075) and feed efficiency (P = 0.066) for heifers that received the antioxidant treatment. An increased number of yield grade 3 carcasses (P = 0.03) and fewer yield grade 1 carcasses (P < 0.01) was observed in the antioxidant treatment group. No differences were detected between treatments for other carcass characteristics or liver abscess incidence and severity. Another trial evaluated intermittent tylosin feeding and its impact on liver abscess incidence and antimicrobial resistant Enterococcus spp. when compared to continuous tylosin feeding. One of 3 treatments were randomly assigned to 312 crossbred steers: negative control (no tylosin fed throughout the feeding period); positive control (tylosin fed throughout the feeding period); or intermittent treatment (tylosin fed intermittently throughout the feeding period: 1week on, 2 weeks off). Fecal samples were collected on day 0, 20, and 118 to characterize antimicrobial resistant Enterococcus spp. By design, the intermittent treatment consumed 60% less tylosin than the positive control group. No differences were detected between treatments for feedlot performance. Liver abscess incidence was greatest for the negative control, and least for the positive control and intermittent treatments, with no difference being detected between the latter two treatments (P = 0.716). Antimicrobial resistance was unaffected by treatment, but was affected by sampling time. We concluded that supplementing antioxidants is not a viable option to reduce liver abscess incidence and severity, and that tylosin usage can be decreased without adversely affecting performance or liver abscess incidence.

Master of Science / Department of Diagnostic Medicine/Pathobiology / Raghavendra Amachawadi / T.G. Nagaraja / Copper is an essential micronutrient that is supplemented in swine diets as a growth promoter. Previous studies suggest a link between copper supplementation and co-selection of antimicrobial resistance (AMR) in Enterococcus, but the data are inconsistent. Therefore, the objective of this study was to assess the impact of copper supplementation, alone or with chlortetracycline (CTC), on prevalence and concentration of copper resistance gene, tcrB, prevalence of tetracycline [tet(M)] and macrolide resistance [erm(B)] genes, and AMR in fecal enterococci of weaned piglets. A total of 320 weaned piglets at 21 days of age were allocated into 64 individual pens distributed equally among two barns. Pen-pair was the experimental unit (n=32). Four treatments were used: a basal diet as the control, a basal diet with 200 ppm of copper as copper sulfate, a basal diet with chlortetracycline (CTC) at 400 g/ton of feed, and a basal diet with 200 ppm of copper and CTC at 400 g/ton of feed. The study period was 35 days with days -7 to -1 as an acclimation period and days 0 to 28 as the treatment period. Direct fecal samples were collected on days 0, 14, and 28. Prevalence of tcrB-positive enterococci was not affected by copper and or CTC supplementation (P > 0.05). Prevalence of tcrB-positive enterococci was higher on day 14 than other sampling days (P = 0.002). Prevalence of tet(M)-positive enterococci was not affected by treatment group or sampling day (P > 0.05). Prevalence of erm(B)-positive enterococci had a significant treatment and sampling day interaction (P = 0.0213). The total copy number of the tcrB gene was quantified as a percent of total bacterial cells in the feces. The median copper MIC of tcrB-negative and -positive isolates was 3 mM and 20 mM, respectively (P < 0.0001). For day 0 (n=64) and day 28 (n=63), all Enterococcus isolates were susceptible to gentamicin, kanamycin, streptomycin, daptomyicin, and tigecycline, with majority of isolates resistant to chloramphenicol, erythromycin, lincomycin, linezolid, tetracycline, tylosin tartrate, and synercid. For day 0 (n=64) and day 28 (n=63), respectively, a total of 61 (95.3%) and 47 (74.6%) isolates were resistant to erythromycin, 51 (79.7%) and 41 (65.1%) to tylosin, and 60 (93.8% and 95.2%) to tetracycline. The results of this study show that supplementing copper, with or without a selection pressure of chlortetracycline, did not increase copper-resistant enterococci and did not co-select resistance to any other antibiotics. Liver abscesses in feedlot cattle have a significant economic impact because of reduction in cattle performance, and carcass yield and liver condemnation at harvest. Fusobacterium necrophorum is the primary causative agent of the liver abscesses. Recently, Salmonella enterica has been isolated from liver abscesses of cattle. Our objectives of this study were to determine prevalence of Salmonella, compare conventional (serological) and commercially available Check &Trace serotyping methods, and to describe the antimicrobial susceptibility patterns of Salmonella isolated from liver abscesses of feedlot cattle. In the 2014 study, the number of liver abscesses positive for Salmonella were higher (P < 0.05) in cattle fed no tylosin in the diet (66/200; 33%) compared to tylosin-fed cattle (31/183; 16.9%). In the 2015 study, Salmonella prevalence tended to be higher in liver abscesses categorized as severe (29/106; 27.4%) compared to mild liver abscesses (38/174; 21.8%), but the difference was not significant. Out of the 164 Salmonella isolated, 152 (92.7%) were used for serotyping and 164 strains were used for antimicrobial susceptibility testing. Serotyping was done by serological method, which is considered as the gold standard, and the commercial Check & Trace method, which is a molecular method based on differences in their DNA sequence. A total of 11 serotypes were identified with Lubbock (66/152; 43.4%) being the predominant serotype, followed by Agona (24/152; 15.8%), Anatum (20/152; 13.2%), and Montevideo (18/152; 11.8%). The commercial identified only a few serotypes correctly suggesting that the method requires further validation. Antimicrobial susceptibility testing was done by microbroth dilution method according to Clinical Laboratory Standards Institute guidelines. A majority of the Salmonella strains were pansusceptible to the antimicrobials included in the panel. Overall, 10 strains (10/164; 6.1%) were resistant to one or more antibiotics and belonged to serotypes Agona, Anatum, Cerro, Lubbock, Mbandaka, and Reading. The top three of nine resistant antibiotics were chloramphenicol (5/10; 50%), streptomycin (5/10; 50%), and tetracycline (6/10; 60%). Whether Salmonella contributes to liver abscess formation or just happen to survive in an abscess initiated by the primary etiologic agent, Fusobacterium necrophorum, remains to be determined.

We report a rare case of Candida glabrata liver abscess and fungemia complicating severe calculus cholecystitis in a 64-year-old female patient who had no history of immunosuppression or diabetes mellitus. The patient underwent cholecystectomy, resection of liver abscess, and systemic antifungal therapy using micafungin. Copyright

() is a commensal organism of the gastrointestinal tract. It rarely causes hepatobiliary infections; however, in the presence of underlying inflammation, immunosuppression, or malignancy, it can cause hepatobiliary infection via an ascending route. Herein, we report a case of pyogenic liver abscess secondary to associated with cholangiocarcinoma, which was treated with ceftriaxone and metronidazole.

Orientador: Mário De Beni Arrigoni / Banca: Telma Terezinha Berchielli / Banca: Mário Sartori Bueno / Banca: Rafael da Costa Cervieri / Banca: José Roberto Sartori / Resumo: O objetivo deste estudo foi estudar os efeitos da suplementação do preparado de anticorpos policlonais (PAP) ou monensina sódica (MON) sobre o desempenho, características de carcaça, perfil metabólico sanguíneo, flutuação da ingestão de matéria seca (IMS) e incidências de rumenites e abscessos de fígado. O delineamento experimental foi inteiramente casualizado em arranjo fatorial 2 × 2, com seis repetições por tratamento, nos quais 48 bovinos machos inteiros de cada grupo genético (GG) avaliado [Brangus (BR) ou Nelore (NE)] foram alimentados com dietas contendo MON ou PAP fornecidos diariamente nas doses de 30 e 300 mg/kg de MS, respectivamente. Os animais passaram por três fases durante o estudo: adaptação (ADAP), crescimento, e terminação. As dietas fornecidas nestes períodos continham 55, 70 e 85% de concentrado, respectivamente. Não foi observado (P > 0,05) efeito principal dos aditivos alimentares (AA) sobre a maioria das características de desempenho, com exceção à IMS em quilos e em porcentagem do peso vivo, onde bovinos recebendo MON apresentaram (P < 0,05) menores IMS. Foi observado (P < 0,01) efeito principal dos AA e dos GG sobre as concentrações de bicarbonato, total de CO2 e excesso de base no fluído extra-celular, onde bovinos recebendo PAP, e aqueles da raça BR, apresentaram maiores concentrações desses metabólitos no sangue. Animais que receberam PAP e aqueles da raça BR, apresentaram maiores (P < 0,01) valores de pH na fase de ADAP que animais suplementados com MON (7,427 vs. 7,400) e animais NE, respectivamente. Bovinos BR apresentaram (P < 0,01) maior ganho de peso diário que bovinos NE em ambas as fases, contudo conversão alimentar similar (P > 0,05). Por outro lado, bovinos NE mostraram maior (P < 0,05) incidência de lesões ruminais. Assim sendo, a suplementação de PAP pode ser uma eventual alternativa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study, conducted at the São Paulo State University feedlot, Botucatu Campus, Brazil, was designed to test monensin (MON) and a polyclonal antibody preparation (PAP) against rumen bacteria on feedlot performance of Brangus (BR) and Nellore (NE) cattle. The experiment was designed as a 2 × 2 factorial arrangement using repeated measures over time, replicated 6 times (4 bullocks/pen), in which 48 8-mo-old bullocks of each of two breeds (BD) evaluated were fed diets containing either MON at 30 mg•kg-1 or PAP at 300mg•kg-1 of dry matter (DM). Measures over time were taken according to the phase and level of concentrate fed during the study: 55, 70 and 85%. Phases were named adaptation (AD), growing (GR), and final (FN), respectively. No significant (P > 0.05) feed additives (FA) main effect was observed for any of the feedlot performance variables, with the exception (P < 0.05) of DM intake expressed in kg (PAP= 7.60; MON=7.24) and in % of body weight (PAP= 2.11; MON=2.03). Feeding MON led to greater (P < 0.05) subcutaneous fat deposition throughout the study, and decreased (P < 0.05) the final rib eye area (RBA). As a result a reduced (P < 0.05) RBA deposition, mainly in GR phase, it was observed when feeding MON was compared to feeding PAP. A significant (P < 0.01) FA and BD main effects were found for bicarbonate, total CO2, and base excess in extracellular fluid, where bullocks receiving PAP, and those BR cattle, presented greater concentrations of these metabolites in the blood. Likewise, BR cattle and bullocks receiving PAP had (P < 0.01) higher blood pH in the AD phase than NE cattle and bullocks fed MON (7.427 vs. 7.400), respectively. BR had greater (P < 0.01) average daily gain in GR and FN phases, but similar (P > 0.05) feed conversion was observed. On the other hand, NE bullocks presented greater (P < 0.05) incidence of rumenites. Thus, feeding PAP may... (Complete abstract click electronic access below) / Doutor

Os trofozoítos de Entamoeba histolytica após se evadirem de uma complexa resposta imune ao nível da mucosa intestinal, invadem o epitélio, podendo disseminar-se pela circulação portal, atingindo o fígado e outros órgãos. A amebíase hepática é a forma mais comum de amebíase extraintestinal e corresponde a menos de 1% dos casos clínicos de amebíase. A modulação das respostas imunológicas frente à administração de substâncias farmacologicamente ativas em modelos experimentais infectados por diferentes patógenos tem contribuído de maneira importante nas investigações de terapias alternativas para colaborar no tratamento das diferentes doenças parasitárias. A melatonina (N-acetil-5- metoxitriptamina) é uma indolamina cuja síntese ocorre na glândula pineal e em vários locais extrapineais, como, as células do sistema imune, retina, medula óssea, pele, leucócitos, e trato gastrointestinal. É uma molécula pleiotrópica que possui atividades imunoestimulatórias e efeitos pró e anti-inflamatórios. O presente estudo teve como objetivo avaliar um possível efeito imunomodulatório subseqüente à administração oral de melatonina em ratos da linhagem Wistar machos infectados no fígado pela cepa HM1-IMSS de Entamoeba histolytica na fase aguda da amebíase hepática experimental. Foram utilizados vários parâmetros como: dosagens das citocinas IFN-?, IL-4, análise por citometria de fluxo das populações celulares TCD3+, TCD4+, TCD8+, CD45+, CD161+ e produção de óxido nítrico. Através dos resultados obtidos, podemos concluir que a melatonina exerceu seus efeitos imunomodulatórios, ora induzindo uma reposta imune mais eficaz de forma a minimizar os efeitos patogênicos da infecção ao mesmo tempo em que exerceu um papel anti-inflamatório na tentativa de manter a homeostase imunológica do hospedeiro, evitando uma exacerbação dessas respostas que certamente iriam influenciar o grau de patogenicidade desta parasitose. / The trophozoites of Entamoeba histolytica after evade a complex immune response at the intestinal mucosal level, invade the epithelial layer and may spread into the portal circulation reaching the liver and other organs. The amoebic liver abscess (ALA) is the most common form of the extraintestinal amebiasis and is less than 1% of clinical cases of human amoebiasis. The modulation of immune responses by the administration of pharmacological active substances in experimental models infected by different pathogens has contributed in investigations of alternative therapies in order to aid the treatment of various parasitic diseases. Melatonin (N-acetyl-5-methoxytryptamine) is an indolamine whose synthesis occurs in the pineal gland and in several extra-pineal locations such as the immune system cells, retina, bone marrow, skin, leukocytes, and gastrointestinal tract. This molecule has pleiotropic effects with immunoenhancing actions besides pro and anti inflammatory effects. The present study aimed to evaluate a possible immunomodulatory effect following the oral administration of melatonin in male Wistar rats infected with the strain HM1-IMSS of E. histolytica during the acute phase of experimental amebic liver abscess. Several immune parameters were evaluated such as of cytokines IFN-?, IL-4, flow cytometry analysis of cell populations TCD3+, TCD4+, TCD8+, CD45+, CD161+, and nitric oxide production. According to our results, we can conclude that melatonin exerted its immunomodulatory actions, once triggering a more accurate host´s immune response reducing the pathogenic effects from the infection and at the same time, exerting an anti-inflammatory role in the attempt to control host´s immune homeostasis, avoiding an exacerbation of these responses that would certainly influence the degree of pathogenicity of this parasitosis.

O presente estudo se baseou em levantamentos retrospectivos e prospectivos obtidos de bovinos abatidos no Frigorífico Bertin, em Lins-SP. No primeiro levantamento consultaram-se os registros do Serviço de Inspeção Federal de ocorrência de alterações hepáticas em 1.568.821 bovinos (85% machos e 15% fêmeas), proveniente de seis Estados (SP, MS, PR, GO, MT e MG) durante os anos de 2002 a 2006. Consideraram-se os animais abatidos no último trimestre de cada ano como terminados em confinamento, sendo os demais criados continuamente em regime extensivo. Os abscessos hepáticos (1,60%) foram a segunda mais freqüente alteração hepática após a teleangectasia (1,67%). A freqüência desses abscessos foi maior em bovinos confinados (2,54%) que nos criados extensivamente (1,28%) e em fêmeas (1,85%) que em machos (1,56%). O confinamento aumenta o fator de risco (FR) de surgimento de abscessos hepáticos na ordem de 2,01 vezes. Maior freqüência de abscessos foi registrada em bovinos oriundos do Paraná, em ambos os sistemas de terminação. No levantamento prospectivo foram acompanhados o abate de 1.617 bovinos nos meses de dezembro de 2007 (n=858) e outubro de 2008 (n=759). Os abscessos hepáticos foram registrados de acordo com a freqüência, tamanho, número e localização dos mesmos em 1.617 animais; a mucosa ruminal foi avaliada (n=1.397) quanto à presença de ruminite, sua classificação e área afetada; e os pulmões (n=759) examinados para a detecção de hepatização pulmonar nas diferentes regiões, lóbos e lóbulos pulmonares, assim como grau de acometimento nos lóbulos. Foram detectados abscessos hepáticos, ruminites e pulmões hepatizados em 3,29%, 11,88% e 8,30% dos animais, respectivamente. Os abscessos estiveram igualmente distribuídos em todas as quatro regiões hepáticas, e na maioria dos casos (78,26%) os mesmos eram de pequeno tamanho (< 2,5cm) e número (até dois/órgão). Foram encontrados quatro tipos de ruminites, sendo a mais freqüente a retração cicatricial (54,22%), seguido de retalhos aderentes (24,10%), vilosidades aderidas (13,25%) e ruminite erosiva (8,43%). Em 32,53% desses casos à área afetada do rúmen ultrapassava os 300cm2. Animais com ruminite apresentavam um altíssimo risco (FR=12,67x) de manifestar abscessos hepáticos e hepatização pulmonar (FR=5,8x), com destaque para a ruminite erosiva. A hepatização pulmonar foi mais freqüente na região ventral (71,4%) que dorsal (28,6%), nos lóbulos esquerdos (59,79%) que direitos (40,21%) e na maioria dos casos acometia apenas um lóbulo (53,97%) não atingindo a hepatização mais do que 50% deste (66,6%). Abscessos hepáticos ocorreram com maior freqüência quando concomitantemente um único lóbulo pulmonar era acometido (FR=3,0x) e este se apresentava com menos de 50% de seu parênquima hepatizado (FR=11,61x). / A retrospective and prospective survey was carried out in cattle slaughtered in a private abattoir in the State of Sao Paulo, Brazil. The first survey was based on the reports done by the Federal Inspection Service of the liver condemnations among 1,568,821 cattle (85% steers; 15% cows and heifers) from six different Brazilian states during 2002 and 2006. Feedlot cattle were mostly slaughtered in the last trimester of each year, while the cattle bred extensively were in the remaining months. The abscesses (1.60%) were the second highest cause of liver condemnation after telangiectasis (1.67%). The frequency of liver abscesses were higher in feedlot cattle (2.54%) than those bred extensively (1.28%), female (1.85%) than male (1.56%). Feedlot increased the outcome (odds ratio OD= 2.01x) of liver abscess. The highest frequency of liver abscess was detected in feedlot and extensively bred cattle from the Parana state. The prospective survey was carried out following the slaughtering of 1,617 cattle during the months of December 2007 (n=858) and October 2008 (n=759). The abscesses frequency, size, number and location in the liver were recorded in all animals; the rumen mucosa (n=1,397) was examined for the presence, type and size of ruminitis; the lungs (n=759) were also examined for detection of consolidation, evaluating the affected region, number of lobes and lesion score. The following frequencies were seen: liver abscess (3.29%), ruminitis (11.88%) and lung consolidation (8.30%). The abscesses were equally distributed in all hepatic regions; most abscesses (78.2%) were small (< 2.5cm) and present in low number (1-2/liver). Four different types of ruminitis were seen: scars (54.22%), adherent contents (21.10%), clumped villi (13.25%) and erosive ruminitis (8.43%). In many cases (32.53%) the ruminitis spread to an area larger than 300cm2. Cattle with ruminitis had a very high risk of contracting liver abscesses (OD=12.67x) and lung consolidation (OR= 5.8x), principally with erosive ruminitis. Lung consolidation was mostly seen in the ventral (71.4%) than dorsal areas (28.6%), in the left (59.79%) than right lobes (40.21%); in most cases a single lobe was affected (53.97%) and less than 50% of the lobe was consolidated (66.6%). Liver abscesses were commonly seen in cattle with a single lobe (OD=3.0x) and less than 50% of this lobe consolidated (OR=11.61x).

Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-19Bitstream added on 2014-06-13T19:03:46Z : No. of bitstreams: 1 millen_dd_dr_botfmvz.pdf: 1326502 bytes, checksum: 08bc5e39d90b72a1b5690395dfc8a16e (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O objetivo deste estudo foi estudar os efeitos da suplementação do preparado de anticorpos policlonais (PAP) ou monensina sódica (MON) sobre o desempenho, características de carcaça, perfil metabólico sanguíneo, flutuação da ingestão de matéria seca (IMS) e incidências de rumenites e abscessos de fígado. O delineamento experimental foi inteiramente casualizado em arranjo fatorial 2 × 2, com seis repetições por tratamento, nos quais 48 bovinos machos inteiros de cada grupo genético (GG) avaliado [Brangus (BR) ou Nelore (NE)] foram alimentados com dietas contendo MON ou PAP fornecidos diariamente nas doses de 30 e 300 mg/kg de MS, respectivamente. Os animais passaram por três fases durante o estudo: adaptação (ADAP), crescimento, e terminação. As dietas fornecidas nestes períodos continham 55, 70 e 85% de concentrado, respectivamente. Não foi observado (P > 0,05) efeito principal dos aditivos alimentares (AA) sobre a maioria das características de desempenho, com exceção à IMS em quilos e em porcentagem do peso vivo, onde bovinos recebendo MON apresentaram (P < 0,05) menores IMS. Foi observado (P < 0,01) efeito principal dos AA e dos GG sobre as concentrações de bicarbonato, total de CO2 e excesso de base no fluído extra-celular, onde bovinos recebendo PAP, e aqueles da raça BR, apresentaram maiores concentrações desses metabólitos no sangue. Animais que receberam PAP e aqueles da raça BR, apresentaram maiores (P < 0,01) valores de pH na fase de ADAP que animais suplementados com MON (7,427 vs. 7,400) e animais NE, respectivamente. Bovinos BR apresentaram (P < 0,01) maior ganho de peso diário que bovinos NE em ambas as fases, contudo conversão alimentar similar (P > 0,05). Por outro lado, bovinos NE mostraram maior (P < 0,05) incidência de lesões ruminais. Assim sendo, a suplementação de PAP pode ser uma eventual alternativa... / This study, conducted at the São Paulo State University feedlot, Botucatu Campus, Brazil, was designed to test monensin (MON) and a polyclonal antibody preparation (PAP) against rumen bacteria on feedlot performance of Brangus (BR) and Nellore (NE) cattle. The experiment was designed as a 2 × 2 factorial arrangement using repeated measures over time, replicated 6 times (4 bullocks/pen), in which 48 8-mo-old bullocks of each of two breeds (BD) evaluated were fed diets containing either MON at 30 mg•kg-1 or PAP at 300mg•kg-1 of dry matter (DM). Measures over time were taken according to the phase and level of concentrate fed during the study: 55, 70 and 85%. Phases were named adaptation (AD), growing (GR), and final (FN), respectively. No significant (P > 0.05) feed additives (FA) main effect was observed for any of the feedlot performance variables, with the exception (P < 0.05) of DM intake expressed in kg (PAP= 7.60; MON=7.24) and in % of body weight (PAP= 2.11; MON=2.03). Feeding MON led to greater (P < 0.05) subcutaneous fat deposition throughout the study, and decreased (P < 0.05) the final rib eye area (RBA). As a result a reduced (P < 0.05) RBA deposition, mainly in GR phase, it was observed when feeding MON was compared to feeding PAP. A significant (P < 0.01) FA and BD main effects were found for bicarbonate, total CO2, and base excess in extracellular fluid, where bullocks receiving PAP, and those BR cattle, presented greater concentrations of these metabolites in the blood. Likewise, BR cattle and bullocks receiving PAP had (P < 0.01) higher blood pH in the AD phase than NE cattle and bullocks fed MON (7.427 vs. 7.400), respectively. BR had greater (P < 0.01) average daily gain in GR and FN phases, but similar (P > 0.05) feed conversion was observed. On the other hand, NE bullocks presented greater (P < 0.05) incidence of rumenites. Thus, feeding PAP may... (Complete abstract click electronic access below)

O presente estudo se baseou em levantamentos retrospectivos e prospectivos obtidos de bovinos abatidos no Frigorífico Bertin, em Lins-SP. No primeiro levantamento consultaram-se os registros do Serviço de Inspeção Federal de ocorrência de alterações hepáticas em 1.568.821 bovinos (85% machos e 15% fêmeas), proveniente de seis Estados (SP, MS, PR, GO, MT e MG) durante os anos de 2002 a 2006. Consideraram-se os animais abatidos no último trimestre de cada ano como terminados em confinamento, sendo os demais criados continuamente em regime extensivo. Os abscessos hepáticos (1,60%) foram a segunda mais freqüente alteração hepática após a teleangectasia (1,67%). A freqüência desses abscessos foi maior em bovinos confinados (2,54%) que nos criados extensivamente (1,28%) e em fêmeas (1,85%) que em machos (1,56%). O confinamento aumenta o fator de risco (FR) de surgimento de abscessos hepáticos na ordem de 2,01 vezes. Maior freqüência de abscessos foi registrada em bovinos oriundos do Paraná, em ambos os sistemas de terminação. No levantamento prospectivo foram acompanhados o abate de 1.617 bovinos nos meses de dezembro de 2007 (n=858) e outubro de 2008 (n=759). Os abscessos hepáticos foram registrados de acordo com a freqüência, tamanho, número e localização dos mesmos em 1.617 animais; a mucosa ruminal foi avaliada (n=1.397) quanto à presença de ruminite, sua classificação e área afetada; e os pulmões (n=759) examinados para a detecção de hepatização pulmonar nas diferentes regiões, lóbos e lóbulos pulmonares, assim como grau de acometimento nos lóbulos. Foram detectados abscessos hepáticos, ruminites e pulmões hepatizados em 3,29%, 11,88% e 8,30% dos animais, respectivamente. Os abscessos estiveram igualmente distribuídos em todas as quatro regiões hepáticas, e na maioria dos casos (78,26%) os mesmos eram de pequeno tamanho (< 2,5cm) e número (até dois/órgão). Foram encontrados quatro tipos de ruminites, sendo a mais freqüente a retração cicatricial (54,22%), seguido de retalhos aderentes (24,10%), vilosidades aderidas (13,25%) e ruminite erosiva (8,43%). Em 32,53% desses casos à área afetada do rúmen ultrapassava os 300cm2. Animais com ruminite apresentavam um altíssimo risco (FR=12,67x) de manifestar abscessos hepáticos e hepatização pulmonar (FR=5,8x), com destaque para a ruminite erosiva. A hepatização pulmonar foi mais freqüente na região ventral (71,4%) que dorsal (28,6%), nos lóbulos esquerdos (59,79%) que direitos (40,21%) e na maioria dos casos acometia apenas um lóbulo (53,97%) não atingindo a hepatização mais do que 50% deste (66,6%). Abscessos hepáticos ocorreram com maior freqüência quando concomitantemente um único lóbulo pulmonar era acometido (FR=3,0x) e este se apresentava com menos de 50% de seu parênquima hepatizado (FR=11,61x). / A retrospective and prospective survey was carried out in cattle slaughtered in a private abattoir in the State of Sao Paulo, Brazil. The first survey was based on the reports done by the Federal Inspection Service of the liver condemnations among 1,568,821 cattle (85% steers; 15% cows and heifers) from six different Brazilian states during 2002 and 2006. Feedlot cattle were mostly slaughtered in the last trimester of each year, while the cattle bred extensively were in the remaining months. The abscesses (1.60%) were the second highest cause of liver condemnation after telangiectasis (1.67%). The frequency of liver abscesses were higher in feedlot cattle (2.54%) than those bred extensively (1.28%), female (1.85%) than male (1.56%). Feedlot increased the outcome (odds ratio OD= 2.01x) of liver abscess. The highest frequency of liver abscess was detected in feedlot and extensively bred cattle from the Parana state. The prospective survey was carried out following the slaughtering of 1,617 cattle during the months of December 2007 (n=858) and October 2008 (n=759). The abscesses frequency, size, number and location in the liver were recorded in all animals; the rumen mucosa (n=1,397) was examined for the presence, type and size of ruminitis; the lungs (n=759) were also examined for detection of consolidation, evaluating the affected region, number of lobes and lesion score. The following frequencies were seen: liver abscess (3.29%), ruminitis (11.88%) and lung consolidation (8.30%). The abscesses were equally distributed in all hepatic regions; most abscesses (78.2%) were small (< 2.5cm) and present in low number (1-2/liver). Four different types of ruminitis were seen: scars (54.22%), adherent contents (21.10%), clumped villi (13.25%) and erosive ruminitis (8.43%). In many cases (32.53%) the ruminitis spread to an area larger than 300cm2. Cattle with ruminitis had a very high risk of contracting liver abscesses (OD=12.67x) and lung consolidation (OR= 5.8x), principally with erosive ruminitis. Lung consolidation was mostly seen in the ventral (71.4%) than dorsal areas (28.6%), in the left (59.79%) than right lobes (40.21%); in most cases a single lobe was affected (53.97%) and less than 50% of the lobe was consolidated (66.6%). Liver abscesses were commonly seen in cattle with a single lobe (OD=3.0x) and less than 50% of this lobe consolidated (OR=11.61x).

Os trofozoítos de Entamoeba histolytica após se evadirem de uma complexa resposta imune ao nível da mucosa intestinal, invadem o epitélio, podendo disseminar-se pela circulação portal, atingindo o fígado e outros órgãos. A amebíase hepática é a forma mais comum de amebíase extraintestinal e corresponde a menos de 1% dos casos clínicos de amebíase. A modulação das respostas imunológicas frente à administração de substâncias farmacologicamente ativas em modelos experimentais infectados por diferentes patógenos tem contribuído de maneira importante nas investigações de terapias alternativas para colaborar no tratamento das diferentes doenças parasitárias. A melatonina (N-acetil-5- metoxitriptamina) é uma indolamina cuja síntese ocorre na glândula pineal e em vários locais extrapineais, como, as células do sistema imune, retina, medula óssea, pele, leucócitos, e trato gastrointestinal. É uma molécula pleiotrópica que possui atividades imunoestimulatórias e efeitos pró e anti-inflamatórios. O presente estudo teve como objetivo avaliar um possível efeito imunomodulatório subseqüente à administração oral de melatonina em ratos da linhagem Wistar machos infectados no fígado pela cepa HM1-IMSS de Entamoeba histolytica na fase aguda da amebíase hepática experimental. Foram utilizados vários parâmetros como: dosagens das citocinas IFN-?, IL-4, análise por citometria de fluxo das populações celulares TCD3+, TCD4+, TCD8+, CD45+, CD161+ e produção de óxido nítrico. Através dos resultados obtidos, podemos concluir que a melatonina exerceu seus efeitos imunomodulatórios, ora induzindo uma reposta imune mais eficaz de forma a minimizar os efeitos patogênicos da infecção ao mesmo tempo em que exerceu um papel anti-inflamatório na tentativa de manter a homeostase imunológica do hospedeiro, evitando uma exacerbação dessas respostas que certamente iriam influenciar o grau de patogenicidade desta parasitose. / The trophozoites of Entamoeba histolytica after evade a complex immune response at the intestinal mucosal level, invade the epithelial layer and may spread into the portal circulation reaching the liver and other organs. The amoebic liver abscess (ALA) is the most common form of the extraintestinal amebiasis and is less than 1% of clinical cases of human amoebiasis. The modulation of immune responses by the administration of pharmacological active substances in experimental models infected by different pathogens has contributed in investigations of alternative therapies in order to aid the treatment of various parasitic diseases. Melatonin (N-acetyl-5-methoxytryptamine) is an indolamine whose synthesis occurs in the pineal gland and in several extra-pineal locations such as the immune system cells, retina, bone marrow, skin, leukocytes, and gastrointestinal tract. This molecule has pleiotropic effects with immunoenhancing actions besides pro and anti inflammatory effects. The present study aimed to evaluate a possible immunomodulatory effect following the oral administration of melatonin in male Wistar rats infected with the strain HM1-IMSS of E. histolytica during the acute phase of experimental amebic liver abscess. Several immune parameters were evaluated such as of cytokines IFN-?, IL-4, flow cytometry analysis of cell populations TCD3+, TCD4+, TCD8+, CD45+, CD161+, and nitric oxide production. According to our results, we can conclude that melatonin exerted its immunomodulatory actions, once triggering a more accurate host´s immune response reducing the pathogenic effects from the infection and at the same time, exerting an anti-inflammatory role in the attempt to control host´s immune homeostasis, avoiding an exacerbation of these responses that would certainly influence the degree of pathogenicity of this parasitosis.