Septicemia decorrente de pododermatites em canários de cor (Serinus canarius) / Septicemia resulting from bumblefoot in color canaries (Serinus canarius)

Relataram-se um surto de pododermatite e quadro septicêmico em aves de um canaril comercial. Quarenta e quatro canários de cor foram escolhidos de forma aleatória, sem distinção de sexo, idade ou cor, os quais vieram a óbito naturalmente, após terem sido afetados pela pododermatite, sem que tivessem se submetido a tratamento prévio. As aves mortas foram encaminhadas para o exame necroscópico, onde amostras de tecidos das áreas afetadas foram colhidas para exames microbiológico, micológico e histológico. Todas as aves necropsiadas apresentavam pododermatite, com inflamação em um ou mais dedos, de aspecto nodular, com ou sem presença de úlceras ou necrose. Staphylococcus aureus plasma coagulase positivo foi isolado dos pés e do fígado de todas as aves. Foi observado que todas as linhagens isoladas foram resistentes aos antimicrobianos da classe das penicilinas (penicilina G e ampicilina) e parcialmente sensíveis ou resistentes à ciprofloxacina. Apenas metade dos isolados foram sensíveis à neomicina e à estreptomicina. Problemas de saúde pública podem estar relacionados ao surgimento de animais reservatórios de cepas multirresistentes para seres humanos contactantes, como neste caso.

An outbreak of bumblefoot and septicemia was reported in birds of commercial breeding. Forty-four color canaries chosen at random, without regard to sex, age or color, which died naturally having been affected with pododermatitis and not undergoing any prior treatment were used. The dead birds were sent for necropsy in which tissue samples from affected areas were taken for microbiological, mycological and histological examination. All necropsied birds had bumblefoot, inflammation in one or more fingers, nodular, with or without the presence of ulcers and necrosis. Staphylococcus aureus plasma-coagulase positive was isolated from the liver and the feet of all birds. It was observed that all isolates were resistant to the penicillin class of antibiotics (penicillin G and ampicillin) and partially sensitive or resistant to ciprofloxacin. Only half of the isolates were sensitive to neomycin and streptomycin. Public health problems may be related to the emergence of animal reservoirs of multi-resistant strains for contacted humans, as in this case.

Efeito materno e paterno sobre as taxas de fertilização e eclosão em curimba (Prochilodus lineatus) / Maternal and paternal effect on fertilization and haching rate in curimba (Prochilodus lineatus)

Avaliou-se o quanto fêmeas e machos contribuem para a variação total das taxas de fertilização e de eclosão em curimba (Prochilodus lineatus). Utilizou-se sêmen criopreservado proveniente de cinco machos para fertilizar ovócitos de seis fêmeas em um esquema fatorial cruzado 5x6, totalizando 30 famílias. Além das características reprodutivas dos machos e fêmeas, foram avaliadas as taxas de fertilização e eclosão para cômputo dos efeitos materno e paterno. Os componentes da variância foram estimados por meio da máxima verossimilhança restrita, sendo construídos intervalos Highest Posterior Density (HPD) para cada componente. Verificou-se que as fêmeas contribuíram muito mais para a variação total em relação aos machos para as taxas de fertilização e eclosão. Para a taxa de fertilização, as fêmeas contribuíram com 26,3% da variação total e os machos com 8,9%. Em relação à taxa de eclosão, as fêmeas contribuíram com 11,9% e os machos com 1,6%. Concluiu-se que houve efeito materno sobre as taxas de fertilização e eclosão e que o efeito paterno avaliado individualmente foi pouco expressivo ou até mesmo insignificante.

The aim of this study was to evaluate how much females and males contribute to the total variation of reproductive traits such as fertilization and hatching rate in curimba Prochilodus lineatus. Cryopreserved semen from five males was used to fertilize eggs from six females in a cross-factorial 5x6, totaling 30 families. In addition to the reproductive characteristics of males and females, fertilization and hatching rates were evaluated for computation of maternal and paternal effects. The variance components were estimated by restricted maximum likelihood, and the Highest Posterior Density (HPD) intervals were estimated for each component. The female contributed more to the total variation than males for the fertilization and hatching rates. The female contributed 26.3% of the total variation in the fertilization rate against 8.9% of males. Regarding the hatching rate, the female contributed 11.9% versus 1.6% of males. Thus, there is maternal effect on rates of fertilization and hatching, and the paternal effect assessed individually was lackluster or even negligible.

Vincristine delays gastric emptying and gastrointestinal transit of liquid in awake rats

We evaluated the effects of vincristine on the gastrointestinal (GI) motility of awake rats and correlated them with the course of vincristine-induced peripheral neuropathy. Vincristine or saline was injected into the tail vein of male Wistar rats (180-250 g) on alternate days: 50 µg/kg (5 doses, N = 10), 100 µg/kg (2, 3, 4 and 5 doses, N = 49) or 150 µg/kg (1, 2, or 5 doses, N = 37). Weight and stool output were measured daily for each animal. One day after completing the vincristine treatment, the animals were fasted for 24 h, gavage-fed with a test meal and sacrificed 10 min later to measure gastric emptying (GE), GI transit and colon weight. Sensory peripheral neuropathy was evaluated by hot plate testing. Chronic vincristine treatments with total cumulative doses of at least 250 µg/kg significantly decreased GE by 31-59 percent and GI transit by 55-93 percent. The effect of 5 doses of vincristine (150 µg/kg) on GE did not persist for more than 1 week. Colon weight increased after 2 and 5 doses of vincristine (150 µg/kg). Fecal output decreased up to 48 h after the fifth dose of vincristine (150 µg/kg). Vincristine decreased the heat pain threshold 1 day after 5 doses of 50-100 µg/kg or after 3-5 doses of 150 µg/kg. This effect lasted for at least 2 weeks after the fifth dose. Chronic intravenous vincristine treatment delayed GE and GI transit of liquid. This effect correlated with the peak increase in colon weight but not with the pain threshold changes.

Avaliaçäo da funçäo mitochondrial do fígado submetido a isquemia parcial com e sem pré-condicionamento isquêmico / Evaluation of liver mitochondrial function submitted to partial ischemia with and without ischemic preconditioning

Estudou-se o papel do pré-condicionamento isquêmico de 5 minutos sobre o efeito da isquemia hepática de 2 horas seguida de reperfusäo de 1 hora. Verificou-se a Razäo de Controle Respiratório (RCR) foi significativamente maior nos animais submetidos à isquemia hepático com pré-condicionamento prévio de 5 minutos.

Modelos experimentais cirúrgicos de falência hepática fulminante / Surgical experimental models of fulminant liver faillure

Os autores fazem uma revisäo pormenorizada sobre os principais modelos cirúrgicos experimentais de falência hepática fulminante. Abordam aspectos da induçäo experimental das vantagens e desvantagens dos diferentes modelos, tecendo comentários sobre os modelos de induçäo da falência hepática, e das possíveis formas de diagnóstico e tratamento.

Aspecto funcional do remanescente hepático em condiçöes de isquemia e reperfusäo após hepatectomia parcial / Functional aspects of hepatic remmanescent in ischemia and reperfusion condiction after parcial hepatectomy

O efeito da hipotermia, precondicionamento isquêmico e drogas protetoras das lesöes de isquemia e reperfusäo têm sido amplamente estudado. O objetivo do presente estudo é avaliar os efeitos da deferoxamina na isquemia e reperfusäo sobre o fígado remanescente após ressecçäo hepática parcial a 70 por cento, avaliando-se a funçäo mitocondrial hepática. Estudou-se 34 ratos divididos em grupos: Grupo HP (n = 8) - submetidos a hepatectomia parcial (HP) a 70 por cento; Grupo HPD (n = 4) - submetidos a administraçäo de deferoxamina (40 mg/kg) e HP a 70 por cento; Grupo HPI (n = 7) - hepatectomizados (HP a 70 por cento) e submetidos a isquemia (40 minutos); Grupo HPID (n = 7) - semelhante ao anterior, porém recebendo previamente deferoxamina; Grupo C (n = 8) - controle, submetido a operaçäo simulada para HP a 70 por cento. A análise estatística entre os diversos grupos foi feita pelos testes de Kruskal - Wallis e de Mann - Whitney, com nível de significância de 5 por cento. Dessa maneira, o estado III foi semelhante em todos os procedimentos; o estado IV: C

Decreased gastric emptying and gastrointestinal and intestinal transits of liquid after complete spinal cord transection in awake rats

We studied the effect of complete spinal cord transection (SCT) on gastric emptying (GE) and on gastrointestinal (GI) and intestinal transits of liquid in awake rats using the phenol red method. Male Wistar rats (N = 65) weighing 180-200 g were fasted for 24 h and complete SCT was performed between C7 and T1 vertebrae after a careful midline dorsal incision. GE and GI and intestinal transits were measured 15 min, 6 h or 24 h after recovery from anesthesia. A test meal (0.5 mg/ml phenol red in 5 percent glucose solution) was administered intragastrically (1.5 ml) and the animals were sacrificed by an iv thiopental overdose 10 min later to evaluate GE and GI transit. For intestinal transit measurements, 1 ml of the test meal was administered into the proximal duodenum through a cannula inserted into a gastric fistula. GE was inhibited (P<0.05) by 34.3, 23.4 and 22.7 percent, respectively, at 15 min, 6 h and 24 h after SCT. GI transit was inhibited (P<0.05) by 42.5, 19.8 and 18.4 percent, respectively, at 15 min, 6 h and 24 h after SCT. Intestinal transit was also inhibited (P<0.05) by 48.8, 47.2 and 40.1 percent, respectively, at 15 min, 6 h and 24 h after SCT. Mean arterial pressure was significantly decreased (P<0.05) by 48.5, 46.8 and 41.5 percent, respectively, at 15 min, 6 h and 24 h after SCT. In summary, our report describes a decreased GE and GI and intestinal transits in awake rats within the first 24 h after high SCT

Variations in gastric emptying of liquid elicited by acute blood volume changes in awake rats

We have observed that acute blood volume expansion increases the gastroduodenal resistance to the flow of liquid in anesthetized dogs, while retraction decreases it (Santos et al. (1991) Acta Physiologica Scandinavica, 143:261-269). This study evaluates the effect of blood volume expansion and retraction on the gastric emptying of liquid in awake rats using a modification of the technique of Scarpignato (1980) (Archives Internationales de Pharmacodynamie et de Therapie, 246:286-294). Male Wistar rats (180-220g( were fasted for 16 h with water ad libitum and 1.5 ml of the test meal (0.5 mg/ml phenol red solution in 5 percent glucose) was delivered to the stomach immediately after random submission to one of the following protocols: 1) normovolemic control (N=22), 2) expansion (N=72) by intravenous infusion (1 ml/min) of Ringer-bicarbonate solution, volumes of 1,2,3 or 5 percent body weight, or 3) retraction (N-22) by controlled bleeding (1.5 ml/100g). Gastric emptying of liquid was inhibited by 19-51.2 percent (P<0.05) after blood volume expansion (volumes of 1,2,3 or 5 percent body weight). Blood volume expansion produced a sustained increase in central venous pressure while mean arterial presure was transiently increased during expansion (P<0.05). Blood volume retraction increased gastric emptying by 28.5-49.9 percent (P<0.05) and decreased central venous pressure and mean arterial pressure (P<0.05). Infusion of the shed blood 10 min after bleeding reversed the effect of retraction on gastric emptying. These findings suggest that gastric emptying of liquid is subject to modulation by the blood volume.

Acute blood volume expansion delays the gastrointestinal transit of a charcoal meal in awake rats

The present study evaluates the effect of blood volume expansion on the gastrointestinal transit of a charchoal meal (2.5 ml of an aqueous suspension consisting of 5 percent charcoal and 5 percent gum arabic) in awake male Wistar rats (200-270 g). On the day before the experiments, the rats were anesthetized with ether, submitted to left jugular vein cannulation and fasted with water ad libitum until 2 h before the gastrointestinal transit measurement. Blood volume expansion by iv infusion of 1 ml/min Ringer bicarbonate in volumes of 3, 4 or 5 percent body weight delayed gastrointestinal transit at 10 min after test meal administration by 21.3-26.7 percent (P<0.05), but no effect was observed after 1 or 2 percent body weight expansion. The effect of blood volume expansion (up to 5 por cento body weight) on gastrointestinal transit lasted for at least 60 min (P<0.05). Mean arterial pressure increased transiently and central venous pressure increased and hematocrit decreased (P<0.05). Subdiaphragmatic vagotomy and yohimbine (3 mg/kg) prevented the delay caused by expansion on gastrointestinal transit, while atropine (0.5 mg/kg), L-NAME (2 mg/kg), hexamethonium (10 mg/kg), prazosin (1 mg/kg) or propranolol (2 mg/kg) were ineffective. These data show that blood volume expansion delays the gastrointestinal transit of a charcoal meal and that vagal and yohimbine-sensitive pathways appear to be involved in this phenomenon. The delay in gastrointestinal transit observed here, taken together with the modifications of gastrointestinal permeability to salt and water reported by others, may be part of the mechanisms involved in liquid excess management

Acute extracellular fluid volume changes increase ileocolonic resistancce to saline flow in anesthetized dogs

We determined the effect of acute extracellular fluid volume changes on saline flow through 4 gut segments (ileocolonic, ileal, ileocolonic sphincter and proximal colon), perfused at constant pressure in anesthetized dogs. Two different experimental protocols were used: hypervolemia (iv saline infusion, 0.9 per cent NaCl, 20 ml/min, volume up to 5 per cent body weight) and controlled hemorrhage (up to a 50 per cent drop in mean arterial pressure). Mean ileocolonic flow (N = 6) was gradually and significantly decreased during the expansion (17.1 per cent P<0.05) and expanded (44.9 per cent, P<0.05) periods while mean ileal flow (N = 7) was significantly decreased only during the expanded period (38 per cent, P<0.05). Mean colonic flow (N = 7) was decreased during expansion (12 per cent, P<0.05) but returned to control levels during the expanded period. Mean ileocolonic sphincter flow (N = 6) was not significantly modified. Mean ielocolonic flow (n = 10) was also decreased after hemorhage (retracted period) by 17 per cent (P<0.05), but saline flow was not modified in the other separate circuitis (N = 6,5 and 4 for ileal, ileocolonic sphincter and colonic groups, respectively). The expansion effect was blocked by atropine (0.5 mg/kg, iv) both on the ileocolonic (N = 6) and ileal (N = 5) circuits. Acute extracellular fluid volume retraction and expansion increased the lower gastrointestinal resistances to saline flow. These effects, which could physiologically decrease the liquid volume being supplied to the colon, are possible mechanisms activated to acutely balance liquid volume deficit and excess.