La hexaferrita de plomo (PbFe12O19) ha sido obtenida de forma pura utilizando dos métodos de preparación diferentes, el método de reacción en estado sólido y el método de coprecipitación química. Se encontró que la hexaferrita de plomo preparada por el método de reacción en estado sólido se obtiene al añadir 33.09 % en exceso de óxido de plomo, sinterizando a 950 °C durante una hora. Por otro lado, la hexaferrita preparada por coprecipitación química se obtiene de forma pura a partir de 700 °C, sin añadir exceso alguno de plomo. Se estudiaron las propiedades magnéticas y estructurales de ambas muestras. Se encontró un marcado incremento en el campo coercitivo de la muestra preparada por coprecipitación así como una disminución en la magnetización de saturación comparada con la obtenida por el método de reacción en estado sólido. Este comportamiento se atribuye a las características morfológicas y micro-estructurales inherentes a cada método de preparación.

Pure lead hexaferrite (PbFe12O19) was obtained using two different methods of preparation, the solid state reaction and the chemical coprecipitation. It was found that the lead hexaferrite prepared by the solid state method is obtained without secondary phases by adding 33.09 % of lead oxide as an excess and sintering at 950 °C during one hour, also the pure lead hexaferrite prepared by the coprecipitation method is obtained at 700 °C without lead losses. We studied the structural and magnetic properties of both samples, a remarkable increase was found in the coercivity field of the sample prepared by coprecipitation as well as a reduction of the magnetic saturation, compared with the sample prepared by the solid state reaction. This behavior is attributed to the morphologic characteristics and the microstructure that is obtained in an inherently way to the preparation method.

Relata-se um caso de meningoencefalite causada por Herpesvirus bovino 5 (BoHV-5) heritabilityem uma vaca com cinco anos de idade. O animal manifestou quadro clínico inicial de síndrome medular baixa, caracterizada por incoordenação dos membros pélvicos, sinais estes ainda não descritos para a enfermidade. Dentro de pouco tempo a doença evoluiu para síndrome cerebral, e o óbito ocorreu seis dias após o inicio dos sintomas. Na histopatologia, evidenciou-se meningoencefalite difusa, não supurada, e a confirmação do diagnóstico foi feita por reação em cadeia de polimerase e sequenciamento do segmento parcial da glicoproteína G do vírus. O trabalho confirma a presença do BoHV-5 em Minas Gerais, descreve características clínicas novas para a enfermidade e ressalta sua importância no diagnóstico diferencial das neuropatias bovinas.

A clinical case of meningoencephalitis by Bovine herpesvirus 5 (BoHV-5) in a five-year-old cow was reported. The disease began with low spinal cord signs, characterized by incoordination, and these symptoms had never been related to this illness before. Signs of a brain syndrome were observed and the cow died in six days. At the histopathology, a spread non-supurative meningoencephalitis was diagnosed, and the virus identification was made by PCR and partial sequence of the glycoprotein G. This study confirm the BoHV-5 presence in the State of Minas Gerais, Brazil, describes new clinic characteristics, and show the importance of the disease in the differentiate diagnosis with others bovine central nervous system affections.

As papilas mamárias de 23 búfalas foram avaliadas por meio de exame clínico e ultra-sonográfico. Em oito animais do mesmo grupo, as papilas mamárias foram submetidas ao exame teloscópico. Os resultados mostraram que o exame ultra-sonográfico e a teloscopia podem ser utilizados para a avaliação das papilas mamárias na espécie bubalina. As restrições ao uso desses exames, com a metodologia e os equipamentos empregados, foram: a identificação ultra-sonográfica dos ductos papilares foi precária para as papilas mais curtas, e em matrizes jovens, a resistência do ducto papilar limita o uso de telescopia axial.

All the mammart papillae from 23 water buffaloes were clinically and ultrasonographically examined, and eight animals from the same herd were submitted to theloscopic examination. The results showed that ultrasonography and theloscopy are satisfactory methods to evaluate the mammary papillae of the water buffalo. However, the ultrasonographic identification of the streak canal of the shorter papillae was poor and, it was not possible to proceed with axial theloscopy in some animals, specially the primiparous.

Quinze bezerros da raça Holandesa, desaleitados aos 30 dias de idade, foram utilizados para avaliar os efeitos da inclusão de fontes protéicas alternativas, em substituição às proteínas do leite integral, na formulação de sucedâneos do leite. Os animais foram divididos em três grupos: o grupo controle (C) - recebeu leite em pó integral reconstituído; o grupo sucedâneo SL (soro/leite) recebeu 41,6% da proteína bruta (PB) vinda do concentrado protéico de soro (CPS), 23,1% do soro de leite e 35,3% do leite em pó integral; e o grupo sucedâneo S (soro) recebeu 68% da PB vinda do CPS e 32% do soro de leite. O consumo de concentrado, feno, sal mineral e água foi mensurado diariamente, enquanto o ganho de peso foi avaliado semanalmente. Não houve diferença (P>0,05) para o consumo de concentrado, sal mineral e água entre os grupos, nos períodos avaliados. O consumo de feno e o ganho de peso foram inferiores nos animais do grupo S (P<0,05). A substituição de 100% do leite integral por CPS e soro de leite influenciou negativamente o desempenho.

The effects of alternative protein sources replacing whole milk proteins in milk replacer formulation were evaluated. Fifteen Holstein calves, weaned at 30 days of age, were used to evaluate the intake of concentrate, hay, mineral salt and water, and live weight gain. Animals were divided in three experimental groups: control group (C) - fed whole milk; milk replacer WM group (whey/milk) - fed on 41.6% of crude protein (CP) provided by whey protein concentrate (WPC), 23.1% by whey and 35.3% by whole milk; and milk replacer W group (whey) - fed on 68% of CP provided by WPC and 32% by whey. Starter, hay, mineral and water intakes were daily measured, whereas live weight was weekly recorded. Starter, mineral and water intakes were not different (P>0.05) among the experimental groups. Hay intake and live weight gain were lower (P<0.05) for S group animals. Total replacement of whole milk proteins with whey proteins negatively affected the performance of the calves.

Biopsies from three different depths of the Gluteus medius musclewere obtained from 36 endurance horses, aged 8.42 ± 2.85 years andof both sexes. Twenty of the horses were considered excellent performersaccording to the mean speed of their three fastest records in enduranceevents, two or three years prior to the study. The other 16 horses wereconsidered moderate performers, with a mean racing speed <12.5 km/h(in 120- to 180-km endurance rides), <14 km/h (in 80- to 120-km endurancerides), or <13.5 km/h (in 40- to 60-km endurance rides). The activitiesof citrate synthase (an indicator of the citric acid cycle activity), 3-OH-acyl-CoA-dehydrogenase(a marker for lipid oxidation) and lactate dehydrogenase (an indicatorof anaerobic metabolism) enzymes were also studied. Significant differencesin oxidative enzyme activities but not in the glycolytic lactate dehydrogenaseenzyme activities were recorded between performance categories. Excellentperformers had higher activities of citrate synthase (P<0.001) and 3-OH-acyl-CoA-dehydrogenase(P<0.02) enzymes than the poorest. The three enzyme activities changedsignificantly with the increase of sampling depth within the muscle. Citratesynthase and 3-OH-acyl-CoA-dehydrogenase activities increased by 60% and75%, respectively, and that of lactate dehydrogenase decreased by 23% fromsurface to deep sampling depths. When lactate dehydrogenase/citrate synthaseand lactate dehydrogenase/ 3-OH-acyl-CoA-dehydrogenase enzyme activityratios were regressed on sampling depth in order to describe the generalmetabolic profile of the muscle, a strong linear relationship was foundin both performance groups (P<0.001). The highest intercepts of theseregression lines, found in moderate performers when compared to excellentperformers (P<0.001 and P<0.01 for both ratios), clearly show thatthe best performing endurance horses have a greater aerobic capacity anda relatively lower anaerobic capacity in the Gluteus medius musclethan those horses that have been moderately endurance raced. These resultsshow that fibre metabolic profile of this muscle is directly related tothe athletic ability of the horse for endurance events

El objetivo del estudio fue examinar las actividades de enzimas representativasde rutas metabólicas importantes del músculo esqueléticoen equinos de resistencia con diferente historial en competiciones, conel objeto de explicar si estas diferencias contribuyen a las diferenciasobservadas en el rendimiento funcional. Se obtuvieron biopsias a tres profundidadesdistintas (20, 40, 60 mm) del músculo Gluteus medius en 36equinos participantes en carreras de larga distancia de nivel nacionale internacional, de 8.42 ± 2.85 (media ± desviación típica) años de edad y ambos sexos. Veinte animales fueronconsiderados con un rendimiento excelente en la competición de acuerdocon la velocidad media de sus tres mejores registros en carreras de resistenciadurante los dos o tres años previos al estudio, mientras que 16tuvieron un rendimiento moderado, con una velocidad media en carrera <12.5km/h (en competiciones de 120 a 180 km), <14 km/h (en pruebas de 80a 120 km) o <13.5 km/h (en pruebas de 40 a 60 km/h). Además,se cuantificaron las actividades enzimáticas citrato sintasa (un indicador de la actividad del ciclo del ácido cítrico), 3-OH-acil-CoA-deshidrogenasa(un marcador de la oxidación lipídica) y lactato deshidrogenasa(usada como un marcador anaeróbico) en las muestras musculares.Se detectaron diferencias significativas en las actividades de las enzimasoxidativas pero no en la actividad de la enzima glucolítico lactatodeshidrogenasa. Las actividades citrato sintasa y 3-OH-acil-CoA-deshidrogenasafueron mayores (P<0.001 y P<0.02, respectivamente) en los equinosexcelentes que en los de menor rendimiento. Las actividades enzimáticascambiaron significativamente con la profundidad del músculo. Las actividades de citrato sintasa y de 3-OH-acil-CoA-deshidrogenasa aumentaron el 60% y el 75%, respectivamente, mientras que la actividad de lactato deshidrogenasa disminuyó un 23% desde la zona más superficial a la más profunda del músculo. Al estudiar la regresión de las proporciones de las actividades lactato deshidrogenasa/citrato sintasa y lactato des-hidrogenasa/3-OH-acil-CoA-deshidrogenasa respecto a la profundidad, para describir el perfil metabólico general del músculo, se encontró una fuerte relación lineal (P<0.001) en losdos grupos de animales. Los mayores valores de estas rectas de regresión en los equinos con moderado rendimiento respecto a los de resultados excelentes(P<0.001 y P<0.01 para la ordenada de la recta de ambas proporciones) muestran claramente una mayor capacidad aeróbica en el músculoGluteus medius en los equinos con mejor rendimiento deportivo. Estos resultados indican que el perfil metabólico de este músculo está relacionado con la capacidad atlética de equinos para pruebas de resistencia.