Clara Satisuki Mori

Estudo da capacidade alcalinizante de tampões metabolizáveis em bovinos sadios

Six healthy crossbred yearling 250kg steers were infused intravenously, during four hours, with five liters of each of the six different isotonic solutions of sodium salts containing 150 mMol/l of the bicarbonate, acetate, propionate, L-lactate, D and L-lactate and chloride in a 6 x 6 latin square experimental design. Blood was collected from the jugular vein, anaerobically, for blood gas analysis, samples were obtained at different times throughout the infusion (zero, 1st, 4th and 8th h ). Urine was collect for determining the pH at the same schedule. Higher blood pH was found in cattle infused with all buffers than the chloride infused animals; higher level of blood bicarbonate and base excess were obtained at 4th and 8th h with bicarbonate and L-lactate, as well as with pCO2 at the 8th h. These results show that treatments with B and L lead to a slight accumulation of buffers in the blood, and generate a discrete metabolic alkalosis compensated organically by a small retention of CO2. Best alkalinizing effects are obtained by bicarbonate and L-lactato infusions. Bicarbonate infusions causes a high urinary pH.

Effect of an energy-deficient diet on populations of ciliate protozoans in bovine rumen

Foram utilizados 10 novilhos mesticos com cânula ruminal, distribuidos em dois grupos: no grupo controle (C; n=4) receberam dieta balanceada para ganho diario de 900g; no grupo tratado com carencia pronunciada de energia (CP; n=6), receberam dieta com 30% a menos do nivel de mantenca em energia. Apos 140 dias sob esses regimes de alimentacao, foram coletadas amostras do fluido ruminal e urina, para realizacao de provas bioquimicas e funcionais, antes e as 1, 3, 6 e 9 horas apos o fornecimento do alimento. A carencia energetica resultou em diminuicao significativa na quantidade dos protozoarios Entodinium, Eodinium, Isotricha, Dasytricha, Eremoplastron, Eudiplodinium, Metadinium, Charonina, Ostracodinium e Epidinium. Nao houve efeito da hora de coleta sobre o total de ciliados nos grupos C e CP. Maior numero de formas em divisao binaria foi registrado no grupo C, na sexta e nona horas pos-alimentacao (P<0,019). Observaram-se altas correlacoes positivas entre a contagem total de protozoarios e a fermentacao de glicose, amonia e o indice de excrecao urinaria de alantoina e negativa entre a contagem total de protozoarios e a reducao do azul de metileno, e correlacao media entre a contagem total de protozoarios e os acidos graxos volateis totais. A determinacao da populacao de protozoarios do rumen e um metodo simples de avaliacao, alem de que particularmente auxilia o diagnostico clinico da funcao ruminal.

Modelo de indução de diarréia osmótica em bezerros holandeses

Com o objetivo de avaliar um protocolo de diarreia osmotica induzida, foram utilizados 18 bezerros higidos, com idade entre oito e 30 dias de vida, e peso variando de 37 a 50kg. A diarreia e a desidratacao foram induzidas por meio da administracao de leite integral (16,5mL kg-1), sacarose (4g kg-1), espirolactona e hidroclorotiazida (2mg kg-1), a cada oito horas, durante dois dias. O exame fisico e as coletas de sangue para determinacoes de componentes do hemograma, hemogasometria e de constituintes bioquimicos foram realizados em T0 (0h), T1 (24hi) e T2 (48hi). O protocolo de inducao da diarreia obteve 100% de eficiencia, produzindo diarreia aquosa e desidratacao intensa (13% do peso corporeo) acompanhadas de azotemia pre-renal, aumento nos valores do hematocrito, hemoglobina e proteina total, hipercalemia, hiperlactemia, hiperfosfatemia, acidose metabolica e diminuicao do defict de volume plasmatico e da pressao venosa central.

Ammonia poisoning causes muscular but not liver damage in cattle

Doze novilhos foram experimentalmente intoxicados por administracao intrarruminal com alta dose de ureia (0,5g/kg PV) para estudar o efeito da intoxicacao por ureia sobre o figado e/ou musculatura. Foram coletadas amostras de sangue no decorrer do experimento para determinar o teor de amonia e as atividades de gama glutamiltransferase (gGT), aspartato aminotransferase (AST) e creatina quinase (CK). Onze novilhos apresentaram quadro clinico tipico de intoxicacao por amonia, porem um animal sucumbiu. Animais intoxicados apresentaram alto teor de amonia e elevada atividade de CK e AST. Quanto mais elevados foram os teores de amonia maiores foram as atividades de AST (r=0,59) e CK (0,61). A correlacao entre AST e CK foi alta e significativa (r=0,80), ocorrendo o inverso com AST e gGT (r=0,19). Tanto a atividade de AST como de CK aumentaram significativamente a partir dos episodios convulsivos decorrentes da intoxicacao por amonia. Estes resultados indicam que ocorreu uma expressiva lesao muscular, mas nao hepatica, visto que a CK e uma enzima tipica da musculatura estriada; e o AST encontra-se tanto na musculatura estriada como nos hepatocitos, enquanto que a gGT esta presente somente em celulas hepaticas.

Oxidative profiles of endurance horses racing different distances

Increased oxidative stress during prolonged endurance exercises may result in muscle damage, fatigue and decreased performance. An adequate stress response during training is critical to obtain improved results and high animal welfare standards. The aim of this study was to evaluate the red blood cell haemolysate concentrations of superoxide dismutase (SOD), glutathione peroxidase (GPx), reduced glutathione (GSH) and catalase (CAT) and the plasma concentrations of malondialdehyde (MDA) from endurance horses in different distances at high speed in a tropical climate. Fifteen horses were tested; five at 160km (18.54 - 17.16km/h race speed), five at 120km (21.53 - 17km/h race speed) and five at 80km (20.06 - 18.01km/h race speed). Blood samples were collected at rest, immediately after and three hours after the horses left the final vet check and three, seven and fourteen days after the race. No significant increases (P > 0.05) in the levels of SOD, GPx, GSH, CAT or MDA were observed for any of the times or distances examined. Based on these observations, we conclude that reactive oxygen species (ROS) formation during exercise evokes specific adaptations, such as increased antioxidant/oxidative damage-repairing enzyme activity, increased resistance to oxidative stress and lower levels of oxidative damage.

Survey of sulfur concentration in grasses and inorganic sulfate serum levels in farm-raised cattle in the state of São Paulo, Brazil.

Este trabalho foi realizado em duas etapas. A primeira avaliou a influencia de crescentes quantidades de enxofre (S) dietetico sobre a concentracao de sulfato inorgânico serico (SIS), utilizando-se 14 garrotes para tal. Na posterior, foram estudados os teores de enxofre e proteina bruta (PB) nos capins do genero Brachiaria sp., em 12 fazendas de diferentes areas do Estado de Sao Paulo, nas estacoes seca e chuvosa, e de SIS em 20 bovinos de cada propriedade que nao fossem suplementados com nenhuma fonte dietetica de enxofre. Tanto na primeira quanto na segunda etapa, foram encontrados alto (r = 0,958) e medio (r = 0,478) coeficientes de correlacao entre os teores de enxofre nos capins (EC) e de SIS. Na segunda etapa, tambem existiu alta correlacao positiva (r = 0,806) entre o EC e PB; os teores de enxofre e PB nos capins e de SIS nos bovinos foram maiores no periodo chuvoso que no seco. Tomando por base o requerimento dietetico de enxofre para bovinos (0,20% MS), foi calculado, de acordo com a regressao obtida no primeiro experimento, o valor correspondente de SIS (0,91 mMol L -1 ). Levando-se em conta esses dois valores, 75% dos capins (0,12 ± 0,03) e 83,3% de SIS (0,53 ± 0,20) encontravam-se abaixo dos niveis recomendados, o que demonstra a existencia de carencia de enxofre nos rebanhos paulistas nao-suplementados com este macroelemento. A concentracao serica de sulfato inorgânico pode ser utilizada para predizer o “status” de enxofre em bovinos.

Níveis séricos e hepáticos de cobre, zinco, ferro e molibdênio em ovinos e caprinos criados no semiárido da Bahia

The aim of this research was to know the copper, zinc, iron and molybdenum content in serum and liver of small ruminants raised in the cities of Casa Nova and Juazeiro, state of Bahia, and verify the occurrence of primary or secondary copper deficiency. A total of 160 samples of sheep and goats of both sexes collected in the dry and rainy season were evaluated. The values for serum copper in goats was 13.8±0.3±mol/L and in sheep it was 12.2±0.4 ±mol/L, while the mean liver concentration was 220 ppm for goats and 238 ppm for sheep. The serum zinc value for goats was 28.3±1.0±mol/L and for sheep it was 28.7±0.8±mol/L, while the mean liver concentration was 99 ppm for goats and 92 ppm for sheep. Serum iron value for goats was 61±3±mol/L and for sheep it was 64±2±mol/L, while liver levels were 172 ppm for goats and 221 ppm for sheep. Copper mean values do not indicate the occurrence of copper deficiency in small ruminants raised in the cities studied. Zinc levels were within the normal values and do not require extra supplementation of this mineral. The serum iron levels were elevated, however it did not interfere in copper metabolism in order to result in a cupric deficiency.

Utilização de sal mineral rico em molibdênio na prevenção da intoxicação cúprica acumulativa em ovinos - microminerais hepáticos

The aim of this project is to evaluate the capacity of a molybdenum-rich mineral salt in the prevention of cumulative cooper poisoning (CCP) in sheep, through clinical and hepatic copper and molybdenum concentrations. Twenty five crossbreed Ile-de-France sheep were randomly distributed equally into five groups. Group 1 received a 80% forage and 20% concentrate diet, groups 2 and 3 received a 50% forage and 50% concentrate diet, and groups 4 and 5 received the same diet as groups 2 and 3 with a daily supplementation of 150 mg of copper sulfate. Groups 1, 3 and 5 received a mineral salt with 300 ppm of molybdenum. Three times during the experiment a liver biopsy was carried out to evaluate the degree of copper accumulation. Three sheep from group 4 and one sheep from group 5 showed a clinical picture of CCP. There was no difference in the frequency of mortality between groups 4 and 5 (P=0.56). The liver copper concentration was higher in sheep with CCP (2450 ppm) compared to sheep that did not present CCP (1518 ppm). The higher the ingestion of molybdenum in the diet the lower the liver copper concentration at the end of the experiment (r=-0.72).