Estudios anatomopatológicos, bacteriológicos, moleculares, serológicos e inmunohistoquímicos de <i>Ornithobacterium rhinotracheale</i> en cuadros respiratorios de aves provenientes de explotaciones comerciales

Con el fin de aislar, identificar y describir la posible asociación de Ornithobacterium rhinotracheale con hallazgos histopatológicos e inmunohistoquímicos compatibles con su infección en tejidos respiratorios de aves de producción comercial, se llevaron a cabo tres estudios independientes. En primer lugar, se realizó un estudio retrospectivo abarcando el un total de 82 casos de campo con sospecha de infección por O. rhinotracheale durante el período comprendido entre agosto de 2010 y noviembre de 2012. Un total de 48 casos fueron positivos a la inmunomarcación de la bacteria en pulmón y además se obtuvieron 50 aislamientos beta-hemolíticos y no hemolíticos de O. rhinotracheale. Así también, se determinó la susceptibilidad antibiótica de una selección de 38 aislamientos beta-hemolíticos y no hemolíticos por medio de una técnica de difusión en discos. La mayoría de los aislamientos analizados (34/38) presentó multiresistencia frente a los antibióticos estudiados. En segundo lugar, se realizó un modelo experimental compuesto por 5 grupos de pollos parrilleros de 4 semanas de vida, a fin de identificar posibles diferencias de patogenicidad entre una cepa beta-hemolítica y otra no hemolítica de O. rhinotracheale utilizando las vías de inoculación endovenosa e intratraqueal. Se observó que la vía intratraqueal y la cepa no hemolítica tuvieron un mayor grado de lesión microscópica. El grupo inoculado por vía endovenosa tuvo una mayor proporción de positivos con lesiones microscópicas hepáticas. Finalmente, se realizó la tercer parte, que consistió en un estudio prospectivo en planta de faena de pollos parrilleros. Se encontró que hubo relación entre las lesiones con mayor grado microscópico y la inmunomarción del microorganismo estudiado en el pulmón.The aim of this study was to isolate, identify and describe the possible association between Ornithobacterium rhinotracheale infection, and the histopathological and immunohistochemical findings possibly caused by this microorganism in respiratory tissues of commercial chickens. To this end, three different studies were carried out. The first study was a retrospective study including 82 field cases with respiratory disorders compatible with O. rhinotracheale between August 2010 and November 2012. A total of 48 out of the 82 field cases showed positive immunohistochemical results for the detection of O. rhinotracheale in lungs, and 50 β-hemolytic and non-hemolytic O. rhinotracheale isolates were obtained. Antibiotic susceptibilities of 38 β-hemolytic and non-hemolytic selected isolates were determined by a disk diffusion method. Most of the isolates analyzed (34/38) were multiresistant to the antibiotics studied. The second study was an experimental model composed of five groups of 4-week-old broiler chickens, carried out to identify possible differences of pathogenicity between the β-hemolytic and non-hemolytic O. rhinotracheale isolates by the endovenous and intratracheal inoculation routes. The intratracheal inoculation route and the non-hemolytic O. rhinotracheale isolate showed a higher degree of microscopic lesions. The group endovenously inoculated had a higher proportion of microscopic hepatic lesions. Finally, the third study was a prospective study at a broiler chicken slaughterhouse. The results of this study showed an association between a higher degree of microscopic lesions and positive immunohistochemical results for the detection of the bacterium in lungs.Facultad de Ciencias Veterinaria

Μη-μεταστατικό ειλεακό λειομυοσάρκωμα σε ενήλικο περιστέρι (<i>Columba livia</i>)

Intestinal smooth muscle neoplasms are rarely reported in avian species. An aged male pouter pigeon (Columba livia) had anorexia, somnolence, progressive emaciation and yellowish diarrhea of four days' duration and died despite antibiotic and antiparasitic treatment. At necropsy, the ileum bore a whitish, nodular, 0.8 cm in diameter mass severely narrowing the lumen. Histopathologically, the ileal mass was a well-demarcated, expansile neoplasm severely expanding the tunica muscularis and invading the mucosa. The neoplasm was composed of densely packed spindle cells with elongated nuclei arranged in broad interlacing bundles, and showing mild anisocytosis and anisokaryosis. Immunohistochemically, the neoplasm was positive for desmin and smooth muscle actin, and negative for cytokeratin, and c-kit. The gross, histopathologic and immunohistochemical findings provided the diagnosis of ileal leiomyosarcoma. This is the first report of an ileal leiomyosarcoma in Columbiformes and one of few intestinal smooth muscle neoplasms described in birds.Νεοπλάσματα που προέρχονται από το μυϊκό χιτώνα του εντέρου αναφέρονται σπάνια στα πτηνά. Ενα ενήλικο αρσενικό περιστέρι “pouter” (Columba livia) παρουσιάστηκε με ανορεξία, υπνηλία, προοδευτική απίσχναση και κίτρινη διάρροια διάρκειας 4 ημερών και απεβίωσε παρά τη χορήγηση αντιβιοτικών και αντιπαρασιτικής αγωγής. Νεκροτομικά, ο ειλεός έφερε μία λευκωπή, οζώδη μάζα διαμέτρου 0.8 εκ. η οποία προκαλούσε σοβαρού βαθμού στένωση του αυλού. Ιστοπαθολογικά, η μάζα αποτελείτο από ένα καλά περιγεγραμμένο νεόπλασμα που αφορούσε και επέκτεινε το μυϊκό χιτώνα και διείσδυε στο βλεννογόνο. Το νεόπλασμα αποτελείτο από κυτταρικά εμβριθή πληθυσμό ατρακτοειδών κυττάρων διατεταγμένων σε ευρείες αλληλοπλεκόμενες δεσμίδες, με επιμήκεις πυρήνες και ήπια ανισοκυττάρωση και ανισοπυρήνωση. Ανοσοϊστοχημικά, το νεόπλασμα ήταν θετικό στη δεσμίνη και ακτίνη του λείου μυϊκού ιστού και αρνητικό στην κυτταροκερατίνη και c-kit. Με βάση τα μακροσκοπικά, ιστοπαθολογικά και ανοσοϊστοχημικά ευρήματα, ετέθη η διάγνωση του ειλεακού λειομυοσαρκώματος. Η παρούσα είναι η πρώτη αναφορά ειλεακού λειομυοσαρκώματος σε Columbiformes και μία από τις λίγες αναφορές εντερικών νεοπλασμάτων του λείου μυϊκού χιτώνα σε πτηνά.Facultad de Ciencias Veterinaria

Μη-μεταστατικό ειλεακό λειομυοσάρκωμα σε ενήλικο περιστέρι (<i>Columba livia</i>)

Intestinal smooth muscle neoplasms are rarely reported in avian species. An aged male pouter pigeon (Columba livia) had anorexia, somnolence, progressive emaciation and yellowish diarrhea of four days' duration and died despite antibiotic and antiparasitic treatment. At necropsy, the ileum bore a whitish, nodular, 0.8 cm in diameter mass severely narrowing the lumen. Histopathologically, the ileal mass was a well-demarcated, expansile neoplasm severely expanding the tunica muscularis and invading the mucosa. The neoplasm was composed of densely packed spindle cells with elongated nuclei arranged in broad interlacing bundles, and showing mild anisocytosis and anisokaryosis. Immunohistochemically, the neoplasm was positive for desmin and smooth muscle actin, and negative for cytokeratin, and c-kit. The gross, histopathologic and immunohistochemical findings provided the diagnosis of ileal leiomyosarcoma. This is the first report of an ileal leiomyosarcoma in Columbiformes and one of few intestinal smooth muscle neoplasms described in birds.Νεοπλάσματα που προέρχονται από το μυϊκό χιτώνα του εντέρου αναφέρονται σπάνια στα πτηνά. Ενα ενήλικο αρσενικό περιστέρι “pouter” (Columba livia) παρουσιάστηκε με ανορεξία, υπνηλία, προοδευτική απίσχναση και κίτρινη διάρροια διάρκειας 4 ημερών και απεβίωσε παρά τη χορήγηση αντιβιοτικών και αντιπαρασιτικής αγωγής. Νεκροτομικά, ο ειλεός έφερε μία λευκωπή, οζώδη μάζα διαμέτρου 0.8 εκ. η οποία προκαλούσε σοβαρού βαθμού στένωση του αυλού. Ιστοπαθολογικά, η μάζα αποτελείτο από ένα καλά περιγεγραμμένο νεόπλασμα που αφορούσε και επέκτεινε το μυϊκό χιτώνα και διείσδυε στο βλεννογόνο. Το νεόπλασμα αποτελείτο από κυτταρικά εμβριθή πληθυσμό ατρακτοειδών κυττάρων διατεταγμένων σε ευρείες αλληλοπλεκόμενες δεσμίδες, με επιμήκεις πυρήνες και ήπια ανισοκυττάρωση και ανισοπυρήνωση. Ανοσοϊστοχημικά, το νεόπλασμα ήταν θετικό στη δεσμίνη και ακτίνη του λείου μυϊκού ιστού και αρνητικό στην κυτταροκερατίνη και c-kit. Με βάση τα μακροσκοπικά, ιστοπαθολογικά και ανοσοϊστοχημικά ευρήματα, ετέθη η διάγνωση του ειλεακού λειομυοσαρκώματος. Η παρούσα είναι η πρώτη αναφορά ειλεακού λειομυοσαρκώματος σε Columbiformes και μία από τις λίγες αναφορές εντερικών νεοπλασμάτων του λείου μυϊκού χιτώνα σε πτηνά.Facultad de Ciencias Veterinaria

Gangrenous dermatitis in chickens and turkeys

Gangrenous dermatitis (GD) is a disease of chickens and turkeys that causes severe economic losses in the poultry industry worldwide. Clostridium septicum, Clostridium perfringens type A, and occasionally Clostridium sordellii are considered the main causes of GD, although Staphylococcus aureus and other aerobic bacteria may also be involved in some cases of the disease. GD has become one of the most significant diseases of commercial turkeys in the United States. Several infectious and/or environmental immunosuppressive factors can predispose to GD. Skin lesions are considered to be the main portal of entry of the microorganism(s) involved. GD is characterized by acute onset of mortality associated with gross skin and subcutaneous tissue lesions consisting of variable amounts of serosanguineous exudate together with emphysema and hemorrhages. The underlying skeletal muscle can also be involved. Ulceration of the epidermis may be also noticed in cases complicated with S. aureus. Microscopically, necrosis of the epidermis and dermis, and subcutaneous edema and emphysema are commonly observed. Gram-positive rods can be identified within the subcutis and skeletal muscles, usually associated with minimal inflammatory infiltrate. A presumptive diagnosis of GD can be made based on history, clinical signs, and gross anatomic and microscopic lesions. However, confirmation should be based on demonstration of the causative agents by culture, PCR, immunohistochemistry, and/or fluorescent antibody tests.Facultad de Ciencias Veterinaria

Unusual gross presentation of sarcocystis-like pectoral muscle lymphoma attributed to Marek’s disease in a backyard chicken

Marekʼs disease–induced lymphomas of skeletal muscle are rarely reported in chickens. Three mixed-breed, adult backyard chickens, which belonged to a flock with a previous history of anorexia, depression, ruffled feathers, whitish diarrhea, weight loss and death, were submitted for postmortem examination and diagnostic testing. Grossly, 2 birds had moderate pectoral atrophy, whereas the remaining chicken had numerous white, rice-grain sized foci distributed throughout the pectoral musculature. Severe proventricular wall thickening was observed in all 3 chickens and moderate intestinal Ascaridia spp. parasitism was diagnosed in 2 of the birds. Microscopically, the peripheral nerves, cerebrum, proventriculus, and pectoral musculature were severely infiltrated by mononuclear pleomorphic cells. Formalin-fixed, paraffin-embedded tissues from all 3 chickens were polymerase chain reaction positive for Marekʼs disease virus. A diagnosis of Marekʼs disease was based on the combined necropsy, histopathology, and polymerase chain reaction findings. This article describes the unusual gross presentation of rice-grain sized and shaped lymphomas in the pectoral musculature of chickens caused by Marekʼs disease.Facultad de Ciencias Veterinaria

Effect of Type of Hay and Concentrate Level in Intake and Digestibility in Diets for Goats

The aim of this study was to evaluate the effect of the level of hay and concentrate on total hay intake and supplied already, the additive/substitutive effect and total apparent digestibility of the diet intake in diets for goats. Experiment I: diets: Alfalfa hay (A1), Alfalfa hay + corn (0.5% LW/day) (A2), + 1% LW/day (A3), + 1.5% LW/day (A4). Experiment II: diets: Natural grassland hay (CN) (R1), hay CN + corn (0.5% LW/day) (R2), hay CN + corn (1% of LW/day) (R3), + 1.5% of LW/day) (R4). Intake, ratio forage/concentrate and total apparent digestibility were calculated. Experiment I: There were no effects (p&gt; 0.05) on the CMST for the corn tested levels and recorded a linear decrease (p &lt;0.05) in the CTFDN, CTFDA and CTPB. The CMSF decreased linearly (p &lt;0.05) with increasing amounts of corn by verifying a hay effect on the concentrate. The F/C was different (p &lt;0.05) in all treatments. The DTAIVMS increases linearly (p &lt;0.05) with the content of corn in the diet. Experiment II: a linear increase (p &lt;0.05) on the CMST and CTPB with increasing corn in diet and no differences (p&gt; 0.05) on the CMSF, CTFDN and CTFDA is observed. The F/C and CTPB differ (p &lt;0.05) among all the diets tested. The DTAIVMS increases linearly (p &lt;0.05) with the content of corn in the diet. Therefore, it can be concluded that the increase of maize levels improved the total digestibility of the ration consumed and the substitute or additive effect depended on the quality of the hay used.Facultad de Ciencias Veterinaria

Effect of Type of Hay and Concentrate Level in Intake and Digestibility in Diets for Goats

The aim of this study was to evaluate the effect of the level of hay and concentrate on total hay intake and supplied already, the additive/substitutive effect and total apparent digestibility of the diet intake in diets for goats. Experiment I: diets: Alfalfa hay (A1), Alfalfa hay + corn (0.5% LW/day) (A2), + 1% LW/day (A3), + 1.5% LW/day (A4). Experiment II: diets: Natural grassland hay (CN) (R1), hay CN + corn (0.5% LW/day) (R2), hay CN + corn (1% of LW/day) (R3), + 1.5% of LW/day) (R4). Intake, ratio forage/concentrate and total apparent digestibility were calculated. Experiment I: There were no effects (p&gt; 0.05) on the CMST for the corn tested levels and recorded a linear decrease (p &lt;0.05) in the CTFDN, CTFDA and CTPB. The CMSF decreased linearly (p &lt;0.05) with increasing amounts of corn by verifying a hay effect on the concentrate. The F/C was different (p &lt;0.05) in all treatments. The DTAIVMS increases linearly (p &lt;0.05) with the content of corn in the diet. Experiment II: a linear increase (p &lt;0.05) on the CMST and CTPB with increasing corn in diet and no differences (p&gt; 0.05) on the CMSF, CTFDN and CTFDA is observed. The F/C and CTPB differ (p &lt;0.05) among all the diets tested. The DTAIVMS increases linearly (p &lt;0.05) with the content of corn in the diet. Therefore, it can be concluded that the increase of maize levels improved the total digestibility of the ration consumed and the substitute or additive effect depended on the quality of the hay used.Facultad de Ciencias Veterinaria

Unusual gross presentation of sarcocystis-like pectoral muscle lymphoma attributed to Marek’s disease in a backyard chicken

Marekʼs disease–induced lymphomas of skeletal muscle are rarely reported in chickens. Three mixed-breed, adult backyard chickens, which belonged to a flock with a previous history of anorexia, depression, ruffled feathers, whitish diarrhea, weight loss and death, were submitted for postmortem examination and diagnostic testing. Grossly, 2 birds had moderate pectoral atrophy, whereas the remaining chicken had numerous white, rice-grain sized foci distributed throughout the pectoral musculature. Severe proventricular wall thickening was observed in all 3 chickens and moderate intestinal Ascaridia spp. parasitism was diagnosed in 2 of the birds. Microscopically, the peripheral nerves, cerebrum, proventriculus, and pectoral musculature were severely infiltrated by mononuclear pleomorphic cells. Formalin-fixed, paraffin-embedded tissues from all 3 chickens were polymerase chain reaction positive for Marekʼs disease virus. A diagnosis of Marekʼs disease was based on the combined necropsy, histopathology, and polymerase chain reaction findings. This article describes the unusual gross presentation of rice-grain sized and shaped lymphomas in the pectoral musculature of chickens caused by Marekʼs disease.Facultad de Ciencias Veterinaria

La universidad argentina y el impacto económico del conocimiento globalizado

En las últimas décadas y debido al avance en innovación tecnológica, han ocurrido modificaciones respecto al concepto de trabajo humano otorgándosele mayor valor a la capacidad de realizar tareas complejas, lo que derivaría en un nuevo desarrollo económico y social. Teniendo en cuenta la idea anteriormente mencionada, el objetivo de nuestro trabajo fue realizar una tarea prospectiva analizando los alcances del conocimiento moderno en relación al impacto económico, que el mismo podría tener en un mundo globalizado. Basándonos en que el acopio de trabajo calificado es indicador de desarrollo de una sociedad o país, planteamos la idea del conocimiento como mercancía y de la educación como base de la economía para la realización de nuestra tarea. Asimismo, evaluamos el rol productivo de las universidades y su vinculación con estado y sociedad. Por último, realizamos las consideraciones finales analizando universidades argentinas citando como ejemplo la situación de la Carrera de Ciencias Veterinarias de la UNLP. Podemos concluir que será pertinente en los próximos años que los gobiernos tengan presente en su agenda la discusión de las políticas universitarias que contemplen a las unidades académicas en términos productivos, resguardando a la vez su autonomíaEje temático 4: La gestión curricular e institucional a - Planes de estudios: perfiles profesionales, flexibilización curricular, procesos de cambio y evaluación de la formación profesionalFacultad de Ciencias Agrarias y Forestale

La universidad argentina y los posibles escenarios futuros en la era de la informatización

En los últimos años, la llamada Era de la Información, ha dado origen a nuevos sistemas de interacción cultural y organizaciones sociales. Es por ello que, el objetivo de este trabajo fue plantear los posibles escenarios futuros en materia de políticas de inclusión de tecnologías de la información y la comunicación en la universidad. Así como, su posible impacto en las transformaciones socio-políticas que ocurrirían en el sistema universitario, dentro del marco socio-cultural conocido como “sociedad del conocimiento “. Para la realización de este trabajo se establecieron dos variables, el conocimiento como instrumento de poder y la importancia del saber como capital simbólico. Se estudiaron los cambios en materia de educación superior, en particular universitaria, evaluando la transformación hacia el conocimiento moderno en un mundo globalizado. Asimismo, se elaboraron las consideraciones finales analizando universidades de América Latina en general y, en particular argentinas argumentando como ejemplo la situación de la Carrera de Ciencias Veterinarias de la UNLP. Debido al avance tecnológico en materia educativa se ha logrado estrechar el vínculo entre universidades de América Latina disminuyendo las diferencias entre países de MERCOSUR y fomentando la interacción de las mismas con casas de estudio de otros continentes como las europeas.Eje temático 4: La gestión curricular e institucional a - Planes de estudios: perfiles profesionales, flexibilización curricular, procesos de cambio y evaluación de la formación profesionalFacultad de Ciencias Agrarias y Forestale