Abstract 20. This work compared the effects of two diets high in milk fat of buffaloes with different fatty acid profiles on hepatic fatty degeneration in mice. Male C57BL/6J mice were fed for 154 days with balanced food (control) and two foods rich in milk fat (≈20%): one with a standard profile of fatty acids obtained from buffaloes fed with natural grass (GLP) and another reduced in saturated fats (-31%), rich in rumenic acid (+212,5%) and trans fats (+434,2%, predominantly vaccenic acid) (GLE), obtained from buffaloes fed with natural grass + lipid supplementation. Nutritional parameters, weight gain, cholesterolemia, serum transaminases, liver fat content, and liver histopathology were evaluated. Compared with the control group, GLP and GLE mice were obese, had increased serum ALT, and developed severe liver fatty degeneration (>66% affected parenchyma) with lobular inflammation and hepatocellular ballooning. There weren`t differences between the GLP and GLE groups in food and calorie intake, weight gain, markers of liver damage, cholesterolemia, hepatic lipid content or in liver lesions. The level of fat in the diet and not the type of milk fat was responsible for the observed changes. In conclusion, both high-fat buffalo dairy foods had a similar effect and neither attenuated liver fat degeneration of C57BL/6J mice.

Resumen 16. Este trabajo comparó los efectos de dos dietas altas en grasas lácteas bubalinas con diferente perfil de ácidos grasos sobre la degeneración grasa hepática en ratones. Ratones C57BL/6J, machos, fueron alimentados durante 154 días con alimento balanceado (control) y con dos alimentos ricos en grasas lácteas (≈20%): uno con perfil estándar de ácidos grasos obtenido de búfalas alimentadas con pastura natural (GLP) y otro reducido en grasas saturadas (-31%), rico en ácido ruménico (+212,5%) y grasas trans (+434,2%, predominantemente ácido vaccénico), obtenido de búfalas alimentadas con pasto natural + suplementación lipídica (GLE). Se evaluaron parámetros nutricionales, ganancia de peso, colesterolemia, transaminasas séricas, contenido de grasa hepática e histopatología del hígado. Comparado con el grupo control, los ratones GLP y GLE fueron obesos, registraron incrementos séricos de ALT y desarrollaron una severa degeneración grasa hepática (>66% de parénquima afectado) con inflamación lobular y balonamiento hepatocelular. No hubo diferencias entre los grupos GLP y GLE en el consumo de alimento, las calorías ingeridas, la ganancia de peso, los marcadores de daño hepático, la colesterolemia, el contenido de lípidos hepático o en las lesiones hepáticas. El nivel de grasas en la dieta y no el tipo de grasa láctea fue responsable de los cambios observados. En conclusión, ambos alimentos altos en grasas lácteas bubalinas tuvieron similar efecto y ninguno atenuó la degeneración grasa hepática de ratones C57BL/6J.

This work compared the effects of the two bubaline milk consumption, with low and high ratio of tFA/SFA, on lipemia and the development of hepatic fat degeneration induced by cholesterol in rabbits. Twenty New Zealand males rabbits were randomly separated into a control group (n=10) that received milk with low trans/saturated FA ratio (5.3% tFA and 67.12% SFA) obtained from grazing buffalos; and a high trans group (n=10) that received milk with high tFA/SFA ratio (25.84% tFA and 45.89% SFA) obtained from buffalos with lipid supplementation in their diet. The milk was administered for 75 days and its intake was recorded daily. From day 15, all rabbits were challenged with 0.93 g of cholesterol/day, orally, in order to induce hepatic fat degeneration. The serum lipidogram, ALT and AST were recorded. On the liver, lipid content, sudanophilic area, fibrosis and macrophage infiltration were evaluated. The rabbits voluntarily consumed 9293.13 ml and 9930 ml of milk with low and high tFA/SFA ratio, respectively, without difference between groups (p 0.404). Rabbits in high trans group registered higher serum levels of total cholesterol than the control group (6.08 vs. 5.58 g/l, p 0.049). The ALT were significantly (p <0.0001) higher in the high trans group than the control group. The liver lipids recorded a significant (p 0.0437) increase in the high trans group (10.62%) when it was compared to the control (8.68%).The high trans group recorded a greater extension of the sudanophilic area (37.05 ± 7.53% vs. 26.42 ± 12.55%, p 0.0338), a greater frequency of fibrosis (8 vs. 3 livers, p 0.0247) and more infiltration of macrophages in hepatic parenchyma (94.20 vs. 48 macrophages, p 0.0190) than the control group. In conclusion, milk with high tFA/SFA ratio contributed to increase total cholesterol levels and to increase the hepatotoxic effect of cholesterol, when was compared with milk with a low ratio of tFA/SFA. These effects are possibly related to the tFA content of this milk.

Este trabajo comparó los efectos del consumo de dos leches bubalinas, con baja y alta relación de AGt/AGS, sobre la lipemia y el desarrollo de degeneración grasa hepática inducido por colesterol en conejos. Veinte conejos neozelandeses, machos, fueron aleatoriamente separados en un grupo control (n=10) que recibió leche con baja relación AGt/AGS (5,3% de AGt y 67,12 % de AGS) obtenida de búfalas en sistema pastoril; y un grupo alto trans (n=10) que recibió leche con alta relación AGt/AGS (25,84% de AGt y 45,89% de AGS) obtenida de búfalas con suplementación lipídica en su dieta. La leche fue administrada durante 75 días y su consumo fue registrado diariamente. A partir del día 15 todos los conejos recibieron 0,93 g de colesterol/día, vía oral, para inducir degeneración grasa hepática. Se evaluó el lipidograma sérico y los niveles de ALT y AST. En hígado se midió el contenido de lípidos y, en muestras histológicas, se evaluó el área sudanofílica, la fibrosis e infiltración de macrófagos. Los conejos consumieron 9293,13 ml y 9930 ml de leche con baja y alta relación AGt/AGS, respectivamente, sin diferencia entre grupos (p 0,404). El grupo alto trans registró mayores niveles séricos de colesterol total que el control (6,08 vs. 5,58 g/l, p 0,049). Los valores de ALT fueron significativamente (p <0,0001) mayores en el grupo alto trans. El hígado registró un significativo (p 0,0437) incremento de lípidos en el grupo alto trans (10,62 % de lípidos) cuando se comparó con el control (8,68 % de lípidos). El grupo alto trans registró en el parénquima hepático mayor extensión del área sudanofílica (37,05 % vs. 26,42 %, p 0,0338), mayor frecuencia de fibrosis (8 vs. 3 hígados, p 0,0247) y mayor infiltración de macrófagos (94,20 vs. 48 macrófagos, p 0,0190) que el grupo control. En conclusión, la leche con alta relación AGt/AGS contribuyó a incrementar la colesterolemia y a incrementar el efecto hepatotóxico del colesterol, cuando se comparó con la leche con baja relación de AGt/AGS. Dichos efectos estén, posiblemente, relacionados con el contenido de AGt de esta leche.

There are a variety of wild and domestic animals that have been implicated as reservoirs of Leishmania sp. in America. The domestic dog plays an important role as a reservoir of visceral leishmaniosis, allowing the urban cycle of the disease when the vector is present. The aim of this paper is to present a case of visceral leishmaniosis in a "forest fox" (Cerdocyon thous) by clinical symptoms together with serologic, histopathologic and inmunohistochemistry studies. The finds allowed to confirm the presence of the parasite in several organs. It is important to perform tests to diagnose leishmaniosis in zoo animals before transportation from endemic areas to those free of the disease

En el continente americano existe una gran variedad de animales silvestres y domésticos implicados como reservorios de Leishmania sp. El perro doméstico desempeña un papel importante en la leishmaniosis visceral al conservar el vector en el ciclo urbano de la enfermedad. El objetivo del presente trabajo fue diagnosticar mediante síntomas clínicos y estudios serológico, histopatológico e inmunohistoquímico, un caso de leishmaniosis visceral en un "zorro de monte" (Cerdocyon thous) alojado en un zoo del nordeste argentino. Los estudios realizados permitieron confirmar el diagnóstico al constatarse la presencia del parásito en varios órganos. Se resalta la importancia de realizar pruebas diagnósticas para leishmaniosis antes de trasladar animales de zoológicos desde zonas endémicas hacia regiones consideradas libres de la enfermedad

O objetivo do presente estudo foi avaliar as mudanças no perfil de ácidos graxos do leite de búfalas leiteiras recebendo baixas (B, 276g/d) ou altas (A, 572g/d) doses de uma mistura de óleos de soja e linhaça (70:30, peso/peso) na dieta. Quatorze búfalas multíparas da raça Mediterrânea, mantidas em pastagens nativas, receberam 4kg/dia de um concentrado comercial sem adição de óleo (pré-tratamento) ao longo de umperíodopré-experimental de 10 dias. A produção de leiteindividual e amostras de leite foram coletadas individualmente para determinação dos valores basais de composição e perfil de ácidos graxos do leite nos últimos trêsdias. Após este período, os animais receberam o mesmo concentrado adicionado deBou Apor 26 dias. A produção de leite (g/animal/dia) não diferiu no início (1776 ± 522 e 1662 ± 291para B e A, respectivamente (P<0,622) e no final do período experimental(4590 ±991e4847 ± 447 para LeH, respectivamente, P<0,543). O teor de gordura do leite (g/100g) apresentou valores médios de 77,1(±20,5)paraBe74,3 (±9,9)paraA(P<0,10) durante o período pré-tratamento,mas foi reduzido (P<0,03) após o fornecimento das dietas com óleo para 60,7 (± 23,6) e 49,4 (± 11,2), respectivamente para B e A, não havendo diferenças entre tratamentos (P<0,277). Os teores basais de proteína do leite (B=43,2 ± 3,4 e A=44,3 ± 6,9g/kg) aumentaram após a suplementação com óleo (P<0,0001) em ambos B (73,2 ± 6,0g/kg) e A (68,4 ± 4,9g/kg), não ocorrendo diferenças entre tratamentos (P<0,123). O teor médio basal de 14:0 na gordura do leite (4,76g/100g AG) foi reduzido após a suplementação da dieta com óleo somente no tratamento A (5,29 para 4,03, P<0,007). O teor de 16:0 na gordura do leite foi reduzido (P<0,001) nos tratamentos B (24,49 para 19,75g/100g AG) e A (25,92 para 19,17g/100g AG). A redução nos teores de 12:0+14:0+16:0 na gordura do leite foi maior (P<0,052) em A (32,02 para 23,93g/100g AG) do que em B (30,17 para 25,45g/100g AG). O teor de ácido vacênico (AV) na gordura do leite aumentou (P<0,001) de 5,70 para 13,24g/100g AG em B e de 5,25 para 16,77 em A, resultando em maior teor de AV neste último (P<0,001). O teor basal de ácido rumênico aumentou expressivamente (P<0,001) em B (1,80 para 4,09g/100g AG, +127%) e A (1,60 para 4,61g/100g AG, +187%), não havendo diferenças entre tratamentos (P<0,19). No geral, estes resultados indicam uma melhora pronunciada no valor nutricional da gordura do leite de búfalas a pasto recebendo pequenas quantidades (0,276g/dia) de uma mistura de óleos de soja e linhaça na dieta.

The aim of the study was to examine the changes in milk fatty acid (FA) profile of grazing buffaloes fed either low (L, 276g/d) or high (H, 572g/d) doses of a blend (70:30, wt/wt) of soybean and linseed oils. Fourteen multiparous Mediterranean buffaloes grazing on a native pasture were fed 4 kg/day of a commercial concentrate containing no supplemental oil over a pre-experimental period of ten days. The baseline milk production and composition and milk FA profile were measured over the last three days. After this pre-experimental period the animals received the same concentrate added with either the L or H oil doses for 26 additional days. Milk yield (g/animal/day) did not differ at the start (1776 ± 522 and 1662 ± 291 for L and H, respectively, P<0.622) or at the end of the trial (4590 ± 991 and 4847 ± 447 in L and H, respectively, P<0.543). Baseline milk fat content (g/kg) averaged 77.1 (±20.5) in L and 74.3 (±9.9) in H (P<0.10) and was reduced (P<0.031) to 60.7 (±23.6) and 49.4 (±11.2) (P<0.0031) respectively after L and H with no differences between treatments (P<0.277). Baseline milk protein content (L=43.2 ± 3.4 and H= 44.3 ± 6.9g/kg) increased after oil supplementation (P<0.0001) in both L (73.2 ± 6.0g/kg) and H (68.4 ± 4.9g/kg) without differences between oil doses (P<0.123). Milk fat content of 14:0 decreased after oil supplementation only in the H treatment (5.29 to 4.03, P<0.007) whereas that of 16:0 was reduced (P<0.001) at both L (24.49 to 19.75g/100g FA) and H (25.92 to 19.17g/100g FA) doses. The reduction of total content of 12:0 to 16:0 was higher (P<0.052) in H (32.02 to 23.93g/100g FA) than L (30.17 to 25.45g/100g FA). Vaccenic acid content increased (P<0.001) from 5.70 to 13.24g/100g FA in L and from 5.25 to 16.77 in H, with higher results in the in H treatment (P<0.001). Baseline rumenic acid was sharply increased (P<0.001) in L (1.80 to 4.09g/100g FA, +127%) and H (1.60 to 4.61g/100g FA, +187%) with no differences between L and H (P<0.19). Overall, these results indicate a pronounced improvement in the nutritional value of milk fat from grazing buffaloes fed little amounts (0.276g/day) of a blend of soybean and linseed oils.

To obtain an experimental model of aortic atherosclerosis, male adult New Zealand rabbits were fed with three doses of dietary cholesterol (0.62, 0.93 and 1.24 g/day) for 60 days. Serum cholesterol, HDL and LDL-cholesterol, aspartate aminotransferase (AST), alanin aminotransferase (ALT) and the development of atherosclerosis in aorta, were evaluated. Increased dietary cholesterol from 0.62 to 0.93 g/day resulted in a significant increase (p=0.05) in serum cholesterol (from 6.79 ±2.34 to 9.51 ±0.10 g/l), due mainly to the increase in LDL-cholesterol. The dose of 1.24 g/day did not induce further increase in cholesterolemia compared to the dose of 0.93 g/day. Serum cholesterol was highly variable among rabbits that received 0.62 g/day, this variability was reduced with the highest dose of cholesterol. ALT and AST activities remained normal until day 30 of experience, increasing significantly at day 60 (p=0.05) in the groups receiving cholesterol at the doses of 0.93 and 1.24 g/day, associated with liver fatty degeneration. All doses of cholesterol induced aortic sudanophilic lesion areas of variable surface. Aortic lesions were characterized by a focal increase in intima thickening caused by infiltration of foamy macrophages and smooth muscle mixed in variable proportions with extracellular matrix deposition. In conclusion, the sensitivity of the New Zealand rabbit to develop hypercholesterolemia and atherosclerotic lesions in a short period of time when consuming a high cholesterol diet, is confirmed. The dose of 0.93 g/day for 60 days caused a lower variability in the hypercholesterolemic response among rabbits with significant development of atherosclerotic lesions. This model of early atherosclerosis will allow the study of the atheroprotective effects of different medicines and functional foods.

Para obtener un modelo experimental de ateroesclerosis aórtica, se suministraron tres dosis de colesterol dietético (0,62; 0,93 y 1,24 g/día) durante 60 días a conejos neozelandeses machos adultos. Se evaluaron los niveles séricos de colesterol, colesterol-HDL y LDL, aspartato aminotransferasa (AST) y alanin aminotransferasa (ALT), así como el desarrollo de ateroesclerosis en aorta. El incremento en la dosis de 0,62 a 0,93 g/día de colesterol ocasionó un aumento significativo (p=0,05) en la colesterolemia (de 6,79 ±2,34 a 9,51 ±0,10 g/l), principalmente por incremento del colesterol-LDL. La dosis de 1,24 g/día no indujo aumento adicional de la colesterolemia comparado con la dosis de 0,93 g/ día. La colesterolemia fue muy variable entre los conejos que recibieron 0,62 g/día; las dosis mayores de colesterol redujeron esta variabilidad. Las actividades ALT y AST permanecieron normales hasta el día 30 de la experiencia, incrementándose significativamente en el día 60 (p=0,05) en los grupos que recibieron 0,93 y 1,24 g/día, asociadas a degeneración grasa hepática. Las tres dosis de colesterol indujeron áreas sudanofílicas de extensión variable en aorta. Las lesiones en aorta se caracterizaron por un incremento focal del espesor intimal causado por la infiltración de macrófagos espumosos y músculo liso, entremezclados en proporción variable con depósitos de matriz extracelular. En conclusión, se confirma la sensibilidad del conejo neozelandés a desarrollar hipercolesterolemia y lesiones ateroescleróticas en un corto período de tiempo con una dieta rica en colesterol. La dosis de 0,93 g/día durante 60 días fue la que indujo una respuesta hipercolesterolémica con menor variabilidad entre los conejos y lesiones ateroescleróticas bien desarrolladas. El modelo experimental de ateroesclerosis temprana permitirá estudiar el efecto ateroprotector de diferentes medicamentos y alimentos funcionales.

Estudou-se a influência da suplementação com óleo de peixe sobre a concentração dos ácidos graxos ômega 6 e 3, mostrado no leite de búfala. Foram utilizadas 24 búfalas aleatoriamente selecionadas e distribuídas em três grupos e alimentados com pastagem natural por 49 dias com: nenhum suplemento (grupo I), suplementado com 70mL de óleo de peixe (grupo II) e com 140mL de óleo de peixe (grupo III). A concentração de CLA diferiu (P<0,05) entre os três grupos, com valores máxima de até 7,14mg/g de gordura no grupo II. Não foram observadas diferenças significativas para os ácidos graxos omega 6, sendo o maior valor de 3,82mg/g de gordura no grupo I. Foi observada diferença significativa quanto aos ácidos graxos ômega 3 (P<0,05) nos grupos II e III em relação ao grupo I. O mais elevado valor, 2,42mg/g de gordura foi observado no grupo III. A relação ômega 6/3 mais estreita, 1,37:1, foi observada no grupo III. Os resultados mostram que os animais dos grupos II e III que receberam suplementação de óleo de peixe aumentou significativamente o teor de CLA e de omega 3, com diminuição de omega 6.

The aim of this research work was to investigate the influence of fish oil supplementation on the concentration of conjugated linoleic acid (CLA) and omega 6 and 3 in samples of buffalo milk. A total of 24 female buffaloes separated at random into three groups were fed for 49 days with: natural pasture (group I), supplemented with 70mL of fish oil (group II) and 140mL of fish oil (group III). In the experiment the concentration of CLA showed differences (P<0.05) among the three groups, with a maximum of 7.14mg/g fat in group II. No significant differences were found in omega-6 among the three groups. The highest value of 3.82mg/g fat corresponded to group I, whicht had not been supplemented with fish oil. Significant differences were observed in omega 3 (P<0.05) in groups II and III with respect to group I. The highest average value of 2.42mg/g fat was obtained in group III. The closest relationship omega 6/3 (1.37:1) was observed in group III. As a result, the diets of groups II and III, which included fish oil, increased significantly the content of CLA and omega 3 with reductions in levels of omega 6.

The aim of this work was to detect the presence of Neospora caninum in bovine neonates and bovine spontaneous abortions from Argentine northeast. Histopathological lesions compatible with neosporosis were found in 4 of 26 bovine spontaneous abortions (23 beef herds and 3 dairy herds). The Neospora caninum presence was confirmed with immunohistochemical analysis in encephalic tissue in 3 of 4 fetuses (2 beef herds and 1 dairy herd) that displayed microscopical lesions of neosporosis. Multifocal non-purulent encephalitis, myocarditis and hepatitis were the most relevant lesions. There were no lesions of neosporosis in 10 bovine neonates (8 beef herds and 2 dairy herds). This work confirms the presence of Neospora caninum in spontaneous bovine abortions of beef herds and dairy herds of the Argentine northeast.

El objetivo del presente trabajo fue detectar Neospora caninum en neonatos y fetos bovinos de abortos espontáneos del nordeste argentino. Sobre un total de 26 fetos bovinos abortados espontáneamente (23 de cría y 3 de tambo) se detectaron lesiones histopatológicas compatibles con neosporosis en 4 de ellos. La presencia de Neospora caninum fue confirmada mediante inmunohistoquímica en el encéfalo de 3/4 fetos (2 de cría y 1 de tambo) con lesiones microscópicas compatibles con neosporosis. Las lesiones histopatológicas más relevantes fueron la asociación de encefalitis, miocarditis y hepatitis no purulenta multifocales. De 10 neonatos bovinos procesados (8 de cría y 2 de tambo), no se detectaron animales con lesiones compatibles con neosporosis. Este trabajo confirma la presencia de Neospora caninum en fetos abortados espontáneamente en bovinos de rodeos de cría y de tambo del nordeste argentino.

Wistar male rats, 3 months of age were given ad-libitum a nutritionally adequate diet and demineralized drinking water. The Molybdenum (Mo) and Tungsten (W) were provided in the drinking water at 200 ppm concentration. Intestinal tumors were induced by 1,2-dimethylhydrazine (DMH) given subcuta-neously as 16 weekly doses at 20 mg/kg body weight. Mo in the form of (NH 4 ) 6 Mo 7 O 24 4H 2 O or W in the form of (Na 2 WO 4 ) were provided in the drinking water two months before the first DMH treatment and were continued during 4 months more until the last DMH treatment. Three months after the last carcinogen injec-tion, all animals were sacrificed and examined for intestinal tumors. The number, size and location of the tumors were recorded and the pathology was examined. The addition of Mo to the drinking water induced an increase of hepatic Mo content. At the end of the second month, the hepatic content of Mo was 5.61 ppm, compared with control and W groups (2.18 and 0.96 ppm, respectively). A significantly lower incidence of tumors was observed in the Mo group (47), compared with the control group given DMH alone (105) and W group (113). On the other hand, the Mo group showed a significant decrease in the numbers of multiple tumors per rat.

Bothrops alternatus venom was intramuscularly inoculated (3 mg/kg) into 12 dogs, 30 to 65 days old. Spontaneous bleeding commenced twenty minutes later. Blood samples obtained 3 and 20 minutes after venom inoculation presented spontaneous clotting formation. Plasmatic fibrinogen decreased within 3 minutes. Partial thromboplastin time (PTT) and one-stage prothrombin time (PT) were found. Plasma did not coagulate 40 minutes after inoculation. Platelet counts did not vary but their function was altered. Histopathology pointed out severe muscular necrosis and massive hemorrhage in the inoculation area. Regional ganglia showed intense hemorrhage. The 45 and 65-day-old animals showed alveolar thickening of the septum and generalized congestion, but the 30-day-old animals showed thrombosis of small arteries and arterioles. Renal lesions were different with the age. Cortical tubular necrosis was present in puppies, and intense cortical tubular hydropic degeneration was present in adult dogs. Thymus hemorrhage and necrosis were present.