RESUMO: Descreve-se um surto de hipomagnesemia em bovinos leiteiros da raça Holandês com alimentação a base de pastagens de aveia (Avena sativa) em crescimento no Uruguai, nos meses de maio a julho (outono-inverno) de 2017. De um rebanho de 270 vacas em ordenha, nove (3,3%) morreram. As nove vacas tinham entre dois e nove anos, estavam entre a primeira e a sexta lactação e a produção diária era de 15,8 a 31,4 litros de leite. Duas vacas que apresentaram sialorreia, espasmos musculares, decúbito lateral, debilidade, opistótono e posteriormente, estado comatoso foram eutanasiadas e necropsiadas. Não foram observadas lesões macroscópicas ou histológicas significantes. Uma vaca com sinais clínicos, não tratada, e oito de 14 vacas sem sinais clínicos, do mesmo rebanho, apresentaram baixos níveis séricos de Mg (menos de 0,7mmol/L). Adicionalmente, as duas vacas com sinais clínicos e seis das 14 vacas sem sinais clínicos apresentaram baixos níveis de Ca sérico. A relação do risco tetanizante K/(Ca+Mg) de duas pastagens de aveia, silagem de milho e ração concentrada foi estimada em 5; 10; 7,73; 2,15 e 0,85, respectivamente. Uma relação K/(Ca+Mg) maior de 2,2 é um indicador do potencial tetanizante da forragem, A diferença entre o aporte e os requerimentos dos minerais foi estabelecida constatando-se deficiência diária de Mg (-0,36g/dia), Na (-25,2g/dia) e Ca (-9,27g/dia). O potássio (K) (184,42g/dia) e o fósforo (P) (12,81g/dia) estavam em excesso. A dieta foi reformulada para corrigir as deficiências e a doença foi controlada mediante a administração diária de 80g de MgO, 80g de CaCO3 e 30g de NaCl por vaca. Conclui-se que a hipomagnesemia é uma doença de importância crescente em gado leiteiro no Uruguai e que deve ser prevenida mediante a formulação correta da dieta.

ABSTRACT: An outbreak of hypomagnesemia is reported in Holstein dairy cattle grazing lush oat (Avena sativa) pasture in Uruguay. Nine of 270 (3.3%) cows died in May-July (autumn-winter) 2017. These nine cows were from 2 to 9-years-old (1st-6th lactation), with 22 to 194 days of lactation and 15.8 to 31.4L of daily milk production. Two cows with acute sialorrhea, muscle spasms, lateral recumbency, weakness, opisthotonos, and coma, were euthanized and necropsied. No significant macroscopic or histological lesions were found. One untreated clinically-affected cow and eight out of 14 clinically healthy cows of the same group under similar management and production conditions had low serum levels of Mg (lower than 0.7mmol/L). Secondarily, both clinically affected cows and six out of 14 healthy cows had low serum Ca levels. The K/(Ca+Mg) ratio of two oat forages, corn silage, and ration was 5.10, 7.73, 2.45, and 0.85, respectively. A K/(Ca+Mg) ratio lower than 2.2 represents a risk for hypomagnesemia. The difference between the contribution-requirement of minerals in the diet was established and a daily deficiency of Mg (-0.36g/day), Na (-25.2g/day) and Ca (-9.27g/day) was found, while K (184.42g/day) and P (12.81g/day) were in excess. The diet was reformulated to correct the deficiencies and the disease was controlled by the daily administration of 80g of magnesium oxide, 80g of calcium carbonate and 30g sodium chloride per cow. It is concluded that hypomagnesemia is a cause of mortality in dairy cattle in Uruguay, and that the condition can be prevented by appropriate diet formulation.

Resumen La composición química y degradabilidad ruminal de los subproductos derivados de la soja pueden verse afectadas según su proceso industrial de obtención. El objetivo de este estudio fue determinar el valor proteico en vacas lecheras de harinas y expeller de soja presentes en Uruguay. Se obtuvieron muestras de estos subproductos en distribuidores de alimentos para vacunos de la cuenca lechera uruguaya. Se analizó la composición química, degradabilidad ruminal in situ (determinando: fracción soluble, tasa de degradación y degradabilidad efectiva) y su fermentescibilidad in vitro. Se comparó la composición química y degradabilidad ruminal in situ de las muestras con la base de datos del programa NRC (NRC, 2001). Todos los resultados fueron comparados a través de un análisis de varianza. Las harinas presentaron menor contenido de extracto etéreo, materia orgánica y mayor contenido proteico (P<0,05), mayor tasa de degradación y degradabilidad efectiva in situ, además de una mayor tasa de producción de gas in vitro en comparación con los expeller (P<0,01). La degradabilidad ruminal in vitro no varió entre subproductos (P=0,432). La comparación de datos con la base del NRC (NRC, 2001) indicó una menor producción de leche (L/d) debido a una mayor degradabilidad ruminal de las harinas y expeller evaluados. En base a las diferencias encontradas entre la composición química y degradabilidad ruminal de los subproductos analizados y los datos incorporados en el programa (NRC, 2001) sería recomendable emplear datos nacionales a la hora de formular dietas.

Summary The chemical composition and ruminal degradability of soybean byproducts can be affected by the industrial processes through which are obtained. The objective of this study was to determine the protein value for dairy cows of soybean meal and expeller present in Uruguay. Samples of soybean meal and expeller were taken from several Uruguayan suppliers. The chemical composition, in situ ruminal degradability (determining: soluble fraction, degradation rate and effective degradability) and its in vitro degradability of protein were analyzed. The chemical composition and in situ ruminal degradability of the samples were compared with the NRC (NRC, 2001) software database. All the results were compared through an analysis of variance. The soybean meal presented a lower content of ether extract and organic matter with a higher protein content (P<0.05), higher rate of degradation and effective degradability in situ, in addition to a higher rate of in vitro gas production when compared with expeller (P<0,01). In vitro ruminal degradability did not vary between byproducts (P=0.432). The results of the simulation indicate that the production is lower than that of which is predicted by the NRC (NRC, 2001), because to a higher protein degradability of soybean meal and expeller evaluated. Based on the differences found between the chemical composition and ruminal degradability of the byproducts analyzed and the data incorporated in the software (NRC, 2001), it would be advisable to use national data when formulating diets.

RESUMO: Para estudar o efeito dos níveis de alimentação pós-desmame sobre o crescimento de novilhas da raça Holandês, 40 animais com 77,7 ± 8,1 dias de idade e 77,5 ± 9,2kg de peso corporal foram agrupados em 10 canetas, sendo que cada caneta foi aleatoriamente designada para um dos seguintes tratamentos por 120 dias: nível de alimentação para atingir um ganho de peso corporal de 600 (TMEDIO) ou 800 (TALTO) g/dia com base em uma ração total misturada. Após este período, todas as novilhas foram tratadas como um único grupo por 150 dias. A ingestão de nutrientes, o comportamento animal, o peso corporal e outras medidas morfológicas foram registrados em cada animal. Como resultado do delineamento experimental, as novilhas TALTO tiveram maior ingestão de nutrientes do que as novilhas TMEDIO, o que refletiu em maior ganho diário de peso corporal, altura dos gomos, circunferência do coração e largura do quadril. No entanto, os tratamentos não tiveram efeito sobre estas variáveis durante o período residual.

ABSTRACT: To study the effect of post-weaning feeding levels on the growth of dairy heifers, 40 animals with 77.7 ± 8.1 days of age and 77.5 ± 9.2kg of body weight were grouped in 10 pens, and each pen was randomly assigned to one of the following treatments for 120 days: feeding level to achieve a body weight gain of 600 (TMEDIUM) or 800 (THIGH) g/day based on a total mixed ration. After this period all heifers were managed as a single group for 150 days. Nutrient intake, behavior, body weight and other morphological measures were recorded in each animal. As a result of the experimental design THIGH heifers had a higher nutrient intake than TMEDIUM heifers, which was reflected in a higher daily weight gain, withers height, heart girth and hip width. However, treatments had no effect on these traits during the residual period.

Abstract In the Southern Hemisphere, ruminants are mostly raised in grazing systems where animals consume forage and are supplemented with low amounts of concentrates. Concentrates are usually given separately and are rapidly ingested. This practice leads to changing rumen environment conditions during the day, may alter the rumen microbial metabolism and could affect host performance. The native ruminal Prevotella bryantii strain 3C5 was administered every 48 h to wethers under experimental conditions simulating Southern-Hemisphere feeding to evaluate its potential as a rumen fermentation modulator. The inoculum potential was assessed on day 17. The ammonia nitrogen (NH3-N), volatile fatty acids and ruminal pH were monitored on a 24-h basis 19 days after the beginning of the experiment, and the microbial community structure was assessed by pyrosequencing. The administration of P. bryantii modified the fermentation products and daily pH values compared to the control. The NH3-N concentration in the rumen of treated animals was significantly higher than that of the untreated animals. Modification of the ruminal environment and fermentation pathways was achieved without altering the general structure of the microbial community or the potential methane production. P. bryantii 3C5 could be considered in potential probiotic formulations for ruminants in semi-intensive systems.

Los linfomas extranodales se encuentran fundamentalmente localizados a nivel del tracto gastrointestinal, pulmones, esqueleto y piel. Los linfomas gastrointestinales son tumores relativamente poco frecuentes y representan entre 1 y 4% de todas las neoplasias gastrointestinales malignas. El estómago es el sitio mas frecuente de presentación. Los linfomas no Hodgkin son el tipo mas frecuente observado a nivel extranodal, la forma más frecuente es el Linfoma de tipo MALT y el inmunofenotipo que se asocia es el B en más de 80% de los casos. Sin embargo los Linfomas extranodales del tracto gastrointestinal asociados a Enfermedad celíaca en más de 90% de los casos corresponden a un inmunofenotipo T. Se analizan 8 casos de Linfomas extranodales digestivos de inmunofenotipo B asociados a Enfermedad celíaca en una revisión de 10 años, realizándose el análisis clínico, endoscópico e inmunomolecular. De los 8 casos, 6 correspondieron a mujeres y 2 a hombres. Se demostró la presencia del virus de Epstein Barr en 4 casos.

Extranodal lymphomas are mainly localized at the Gastrointestinal Tract, Lung, Skeleton and Skin. Gastrointestinal lymphomas are not frequently found and represent 1 to 4 percent of all gastrointestinal malignant neoplasms. The stomach is the most frequently involved site of the extranodal No Hodgkin lymphomas and MALT type are the most frequently observed, 80% B immunophenotype. Nevertheless, more than 90% of gastrointestinal lymphoma associated to celiac disease are T immunophenotype. We analized 8 cases of B immunophenotype gastrointestinal extranodal lymphoma associated to celiac disease ocurring during the last 10 years, taking into account clinical, endoscopic and immunomolecular aspects. Of all 8 cases, 6 of them were women and 2 were men. It was demonstrated Epstein Barr Virus in 4 cases.