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Jatropha cake (jatropha curcas) : hepatotoxic implications | Torta de pinhão-manso (jatropha curcas) : implicações hepatotóxicas
2017
Honorato da Silva, Claucia Aparecida | Da Silva, César José | Flores Quintana, Carolina Isabel | Mendonça, Simone | Nascimento, Camila Aparecida | Marcondes, Vanessa Menegatti | Parente, Bruna Oliveira | Machado de Araújo, Miguel Augusto
Jatropha has been highlighted as an oleaginous potential for the production of biofuel. The cake, produced by oil extraction, could be used in animal feed. However, some varieties of jatropha are toxic by limiting their incorporation into animal diets. The objective of this study was to evaluate the hepatotoxicity of diets added with jatropha cake – JC (Jatropha curcas) in rats. Thirty-five (35) male Wistar adults rats (Rattus norvegicus) with initial weight of 352.1 ± 26.8 g were used. The animals were fed for 21 days with the diets: control, 10, 25, 40 and 50% JC. In the feeding with 50% JC the animals presented themselves prostrate and with piloerection. Development and survival decreased, since the inclusion of JC in diets increased. In rats submitted to 10 and 25% JC there was an increase of 17.52% in the hepatosomatic index in relation to the control group. Increase of JC in the rat diet promoted an increase in the activity of ALT and AST enzymes. Anatomic-histopathological evaluation demonstrated that, regardless of the levels tested, JC in rat diet causes hypertrophy of the hepatocytes, with a reduction in energy reserves. This study demonstrated that the use of JC resulted in decreased food intake, associated with weight loss due to the clinical pattern of toxicity, demonstrated by biochemical and histopathological changes in the liver. It was concluded that the inclusion of jatropha cake in rat feeding presents high hepatotoxic potential leading to lesions in the liver parenchyma. | O pinhão-manso tem se destacado como oleaginosa potencial para a produção de biocombustível. A torta, coproduto da extração do óleo, poderia ser utilizada na alimentação animal. No entanto, algumas variedades de pinhão-manso são tóxicas, limitando sua incorporação em dietas animais. Objetivou-se neste estudo avaliar a hepatotoxicidade de dietas acrescidas de torta de pinhão-manso (Jatropha curcas) em ratos. Foram utilizados trinta e cinco (35) ratos Wistar (Rattus norvergicus) machos adultos com peso inicial de 352,1 ± 26,8 g. Os animais foram alimentados por 21 dias com as dietas: controle, 10, 25, 40 e 50% TPM. Na alimentação com 50% TPM os animais apresentaram-se prostrados e com piloereção. O desenvolvimento e a sobrevivência apresentaram diminuição conforme o aumento da inclusão de TPM nas dietas. Em ratos submetidos a 10 e 25% TPM houve aumento de 17,52% no índice hepatossomático em relação ao grupo controle. O aumento de TPM na dieta de ratos promoveu aumento da atividade das enzimas ALT e AST. A avaliação anatomo-histopatológica revelou que, independentemente dos níveis testados, a TPM na alimentação de ratos provoca hipertrofia dos hepatócitos, com redução das reservas energéticas. Este estudo demonstrou que a utilização de TPM resultou em diminuição do consumo de alimento associado à perda de peso devido ao quadro clínico de toxicidade demonstrado pelas alterações bioquímica e histopatológica no fígado. Conclui-se que a inclusão de torta de pinhão-manso na alimentação de ratos apresenta alto potencial hepatotóxico levando a lesões no parênquima hepático.
Mostrar más [+] Menos [-]Effects of Lactobacillus acidophilus DSM13241 as a probiotic in healthy adult cats
2006
Marshall-Jones, Z.V. | Baillon, M.L.A. | Croft, J.M. | Butterwick, R.F.
Objective-To evaluate the effect of dietary supplementation with the probiotic strain Lactobacillus acidophilus DSM13241 in healthy adult cats. Animals-15 adult cats. Procedures-Cats were fed a nutritionally complete dry food for 5 weeks. Fecal character was assessed daily, and a single fecal sample and 3-mL blood sample were collected for bacterial enumeration and hematologic analysis, respectively. Cats were then fed the same diet supplemented with L acidophilus DSM13241 (2 X 10(8) CFU/d) for 4.5 weeks. Repeat fecal and hematologic measurements were taken prior to the return to control diet for a 4-week period. Results-The probiotic species was recovered from feces, demonstrating survival through the feline gastrointestinal tract. Probiotic supplementation was associated with increased numbers of beneficial Lactobacillus and L acidophilus groups in feces and decreased numbers of Clostridium spp and Enterococcus faecalis, indicating an altered bacterial balance in the gastrointestinal tract microflora. Fecal pH was also decreased suggesting a colonic environment selective for the beneficial lactic acid bacterial population. Systemic and immunomodulatory effects were associated with administration of L acidophilus DSM13241 including altered cell numbers within WBC subsets and enhanced phagocytic capacity in the peripheral granulocyte population. In addition, plasma endotoxin concentrations were decreased during probiotic feeding, and RBCs had a decreased susceptibility to osmotic pressure. Conclusions and Clinical Relevance-Probiotic strain L acidophilus DSM13241 fed at 2 X 10(8) CFU/d can alter the balance of gastrointestinal microflora in healthy cats. Furthermore, administration of this probiotic results in beneficial systemic and immunomodulatory effects in cats.
Mostrar más [+] Menos [-]Aggregate risk study of exposure to endophyte-infected (Acremonium coenophialum) tall fescue as a risk factor for laminitis in horses
1995
Rohrbach, B.W. | Green, E.M. | Oliver, J.W. | Schneider, J.F.
Loline and ergot alkaloids found in endophyte-infected (Acremonium coenophialum) tall fescue (EITF) cause vasoconstriction of equine vessels in vitro. An aggregate risk study was used to evaluate the association between horses exposed to EITF and development of laminitis. Veterinary teaching hospitals participating in the Veterinary Medical Data Base were grouped by whether equine accessions were likely to have been at high, moderate, or low risk for exposure to EITF. From 1980-1990, there were 185,781 accessions, of which 5,536 had diagnosis of laminitis. Proportion of equine accessions with laminitis reported by veterinary teaching hospitals for high, moderate, and low risks, were 3.41, 3.04, and 2.00 cases/100 accessions, respectively (P < 0.0001). Comparison of the proportion of accessions with laminitis in the high- and moderate-risk groups with that in the low-risk group revealed significant differences between risk groups over all months (P = 0.063) and differences from month to month within risk groups (P = 0.0001). If the difference among risk groups is attributed entirely to exposure to EITF, the population-attributable risk is 7 cases/1,000 admissions, or 15% of all admissions for laminitis at veterinary teaching hospitals in our data base. Preliminary data support an association between hoses exposed to EITF and increased risk of laminitis; however, studies at the individual animal level are indicated to confirm this hypothesis.
Mostrar más [+] Menos [-]Influence of aflatoxin and fumonisin B1-containing culture material on growing barrows
1995
Harvey, R.B. | Edrington, T.S. | Kubena, L.F. | Elissalde, M.H. | Rottinghaus, G.E.
Aflatoxin (AF)-contaminated and fumonisin B1 (FB1)-contaminated (culture material from Fusarium moniliforme) diets were fed singly and in combination to growing cross-bred barrows. Six barrows (3 replicates of 2 each; mean body weight, 17.5 kg) per group were fed: 0 mg of AF and 0 mg of FB1/kg of feed (control); 2.5 mg of AF/kg of feed; 100 mg of FB1/kg of feed; or 2.5 mg of AF plus 100 mg of FB1/kg of feed for 35 days. The effects on production performance, serum biochemical, hematologic, immunologic, and pathologic measurements were evaluated. Body weight, gain, and feed consumption were significantly (P < 0.05) decreased by AF and AF plus FB1 diets. The FB1 diet decreased feed consumption, and although body weight was numerically decreased, it was not statistically significant. Aflatoxin increased serum gamma-glutamyltransferase (GGT) activity and total iron concentration and decreased urea nitrogen concentration and unsaturated iron-binding capacity. The FB1-alone diet increased serum GGT activity, whereas the AF plus FB1 diet increased serum aspartate transaminase, cholinesterase, alkaline phosphatase, and GGT activities, increased RBC count, triglycerides, and total iron concentrations, and decreased unsaturated iron-binding capacity and urea nitrogen concentration. For the most part, the effects of the AF plus FB1 diet on body weight and hematologic measurements could be considered additive. However, the effect of the AF plus FB1 diet on cholinesterase and alkaline phosphatase activities was greater than additive and was a synergistic response. One pig in the FB1-diet group and 2 pigs in the combination-diet group died. Postmortem lesions in pigs of the FB1-diet group consisted of ascites and increased liver weight. Observations at necropsy for pigs of the AF plus FB1-diet group consisted of hydrothorax, ascites, pulmonary edema, gastric erosions and ulceration, and increased liver and spleen weights. The AF diet increased relative liver weight and resulted in liver that was pale, rubbery, and resistant to cutting. Histologic lesions consisted of hepatic necrosis or degeneration, or both, with variable degrees of bile duct proliferation in barrows of the AF-diet groups. Renal tubular nephrosis was observed in barrows of the FB1 diet group, but this was not consistent in the AF plus FB1-diet group. Cell-mediated immunity, as measured by mitogen-induced lymphoblastogenic stimulation index, was decreased in barrows of the AF and FB1-diet groups, and values in barrows given the combination diet were significantly decreased from those in barrows given the single toxin diets. It was concluded that AF and FB1 (from culture material), singly or in combination, can adversely affect clinical performance, serum biochemical, hematologic, and immunologic values and induce lesions in growing barrows. For most of the variables we evaluated under our study conditions and dosages of toxins, measurements were affected more by the combination diet than by either single toxin diet, and the toxic responses could be described as additive or more than additive, particularly for induction of liver disease.
Mostrar más [+] Menos [-]Evaluation of health and ruminal variables during adaptation to grain-based diets in beef cattle
1995
Leedle, J.A.Z. | Coe, M.L. | Frey, R.A.
Health and ruminal variables were intensively measured during adaptation to grain-based diets in 6 beef cattle with fistulated rumens. The cows had been maintained on prairie grass hay-supplemented diets, and were converted to a grain-based finishing ration by feeding each successive diet (diets 1-4, respectively) for a period of 7 days. Each cow was evaluated and samples were obtained 3 times each day for the first 5 days that each diet was fed. Health variables monitored were rectal temperature, pulse, respiratory and rumen motility rates, fecal consistency, demeanor, blood pH, and blood glucose and L(+) lactate concentrations. Ruminal variables monitored were pH and glucose, DL-lactate, and volatile fatty acid concentrations of rumen contents. Data were analyzed by use of a multivariate ANOVA. We determined that most of the health variables were within reference rang limits throughout the adaptation period; however, analysis of pulse and respiratory rates indicated that diets 2 and 4 were stressful. Although blood pH continually decreased during feeding of the 4 diets (7.38 to 7.30), blood L(+) lactate and glucose concentrations had large increases only within diet 4. The pH of ruminal contents decreased progressively from 6.8 to 5.3. Rumen glucose concentration was low (< 1 micromole/ml), except with diet 4 in which values were 8 times higher than for other diets. By the end of the study, the ruminal contents of all animals were acidic (pH < 5.5), and, on the basis of higher than background amounts of ruminal glucose and DL-lactate, it was determined that rumen microbial equilibrium had not yet been achieved. Analysis of results of this study suggested that ruminal imbalance could be evaluated by monitoring pulse and respiratory rates, blood pH, and blood glucose concentrations. Assessment of the rumen alone could be accomplished by monitoring the variables of rumen pH, rumen glucose, and DL-lactate concentrations. Respiratory rate, blood and rumen content pH, and blood L(+) lactate concentrations were significantly (P < 0.001) affected by time after feeding.
Mostrar más [+] Menos [-]Antibody binding of circulating ergot alkaloids in cattle grazing tall fescue
1994
Hill, N.S. | Thompson, F.N. | Dawe, D.L. | Stuedemann, J.A.
Direct evidence linking alkaloids found in endophyte-infected tall fescue forage with the livestock disorder known as fescue toxicosis is lacking. Physiologic effects of fescue toxicosis include reduced serum prolactin concentration in cattle. A monoclonal antibody specific to the lysergic moiety of ergot alkaloids was developed in mice after creating an immunogen by linking lysergol to human serum albumin. The antibody was specific to the lysergic moiety and, therefore, it cross-reacted with ergot alkaloids, lysergic acid, and lysergol. The antibody did not cross-react with alkaloid derivatives that had bromated or hydrogenated lysergic ring moieties. Fescue toxicosis conditions were elicited in yearling Angus steers by permitting them to graze endophyte-infected tall fescue containing > 650 Kg/kg of ergovaline for 60 days. Passive immunization of steers by infusion of the monoclonal antibody increased serum prolactin concentration by 7 ng/ml, beginning immediately after infusion. Control steers did not respond to treatment with bovine serum albumin. Active immunization of yearling Angus heifers with immunogens containing lysergol or ergonovine linked to human serum albumin resulted in an antibody response.
Mostrar más [+] Menos [-]Efficacy of domperidone and sulpiride as treatments for fescue toxicosis in horses
1994
Redmond, L.M. | Cross, D.L. | Strickland, J.R. | Kennedy, S.W.
We evaluated the effectiveness of 2 dopamine antagonists as treatments for fescue toxicosis in horses. Sixteen gravid mares were assigned by breed and expected foaling date to 1 of 3 treatment groups: endophyte-infested control 1.1 mg of domperidone/kg of body weight/d; and 3.3 mg of sulpiride/kg/d. Mares were pastured on endophyte-infected fescue and received 0.454 kg of a corn and dried molasses carrier containing the drug treatment. Treatment started 30 days prior to expected foaling date and continued until parturition. Blood samples were collected, and mammary gland scores were recorded every 5 days. Body weight and body condition scores were obtained every 28 days. Serum was analyzed for prolactin, progesterone, and estradiol-17beta concentrations. Domperidone-treated mares had shorter (P = 0.09) gestation duration and foaled closer (P = 0.07) to their expected parturition date than did control mares. Mammary gland scores were higher (P < 0.05) for domperidone-treated mares than for control mares. By 4 and 9 days after the start of treatment, serum prolactin concentration was higher P < 0.05) in domperidone-treated mares and sulpiride-treated mares, respectively, than in control mares. Domperidone- and and sulpiride-treated mares had higher (P < 0.05) serum progesterone and lower (P < 0.01) estradiol-17beta concentrations than did control mares. These results indicate that domperidone may offer considerable potential as a treatment for fescue toxicosis in horses.
Mostrar más [+] Menos [-]Effects of dietary supplementation of fructo-oligosaccharides on small intestinal bacterial overgrowth in dogs
1994
Willard, M.D. | Simpson, R.B. | Delles, E.K. | Cohen, N.D. | Fossum, T.W. | Kolp, D. | Reinhart, G.
Sixteen IgA-deficient German Shepherd Dogs with small intestinal bacterial overgrowth were randomized into 2 groups. One group was fed a chicken-based kibble diet; the other was fed the same diet, but with 1% fructo-oligosaccharides supplemented at the expense of cornstarch. After being exposed to the diets for 46 to 51 days, the group that ate the supplemented diet had significantly (P = 0.04) fewer aerobic/facultative anaerobic bacterial colony-forming units in fluid from the duodenum/proximal part of the jejunum, as well as in the duodenal mucosa. We could not detect significant differences in the species of bacteria found in the intestine of these 2 groups of dogs. We conclude that at least some dietary carbohydrates can affect small intestinal bacterial populations in dogs with small intestinal bacterial overgrowth.
Mostrar más [+] Menos [-]Effect of short-term exposure of chickens to corticosterone on resistance to challenge exposure with Escherichia coli and antibody response to sheep erythrocytes
1992
Gross, W.B.
Chickens in a low-stress environment (heterophil/lymphocyte ratio 0.31) were given feed containing 30, 40, or 60 mg of corticosterone/kg of feed for 0.5 hour. Between 0.5 to 12 hours later, chickens were exposed to Escherichia coli via the air sac route. For each dose of corticosterone, there was an untreated control group that was exposed to E coli via the air sac route. The prevalence of pericarditis was reduced from 78 to 7% between 2 and 4 hours after exposure. Resistance was associated with heterophil/lymphocyte (H/L) ratios greater than 1.04. Peak H/L ratios correlated positively with amount of corticosterone in the feed. In one experiment, chickens were inoculated IV with sheep erythrocytes at various times after consumption of feed containing corticosterone. Suppression of antibody responsiveness was most pronounced 4 hours later. Antibody responsiveness correlated positively with lymphocyte numbers. Histologic examination of air sacs was made following euthanasia at various times after E coli exposure. Lesions observed in control chickens included: edema at 0.5 hour, beginning of heterophil infiltration at 1 hour, increased edema and heterophil infiltration at 2 hours, and severe edema and heterophil infiltration at 4 hours. Lesions were not observed in chickens that had been given feed containing 40 mg of corticosterone/kg of feed.
Mostrar más [+] Menos [-]Serum amylase activity and calcium and magnesium concentrations in young cattle grazing fescue and Bermuda grass pastures
1992
Nutting, D.F. | Tolley, E.A. | Toth, L.A. | Ballard, S.D. | Brown, M.A.
The study reported here was part of a long-term investigation of the effects of genotype on growth, reproduction, and metabolism in cattle grazing common Bermuda grass and endophyte-infected fescue pastures. In June 1990, blood samples were collected from the tail vein of yearling heifers and steers (Angus [AA], Brahman [BB], and their reciprocal crosses [AB, BA], n = 97). Serum amylase activity was assayed enzymatically; serum Ca and Mg concentrations were determined by atomic absorption spectrophotometry. The effects of endophyte-infected fescue depended on genotype (P < 0.001). In yearlings having at least 1 Angus parent (AA, AB, BA), grazing endophyteinfected fescue was associated with higher serum amylase activity than was grazing Bermuda grass. But serum amylase activities of BB yearlings consuming either forage were similar. Moreover, for either forage, substantial differences were related to genotype (P < 0.007) and gender (P < 0.05). Angus yearlings had higher serum amylase activity than did Brahman yearlings; AB and RA yearlings had intermediate values. Heifers had higher amylase activity than did steers. The relationship among serum values of amylase, Ca, and Mg depended on forage. Yearlings consuming endophyte-infected fescue and having at least 1 Angus parent had a moderate negative correlation between serum amylase activity and Ca concentration (r = -0.53; P < 0.0005); that is, in calves of genotypes with increased amylase activity while consuming endophyte-infected fescue (AA, AB, BA), the higher the amylase activity, the lower the serum Ca concentration. However, in yearlings consuming Bermuda grass, serum amylase and Ca values were not correlated. Conversely, grazing Bermuda grass was associated with moderate positive correlation between Ca and Mg concentrations (r = 0.46; P < 0.0003), but in yearlings grazing endophyte-infected fescue, Ca and Mg concentrations were independent. The cause, pathophysiologic mechanism, and clinical importance of these effects remain to be determined. In conclusion, serum amylase activity in yearling cattle was influenced by genotype, gender, and consumption of endophyte-infected fescue. We speculate that yearlings having at least 1 Angus parent may develop a persistent subclinical derangement of the exocrine portion of the pancreas when exposed to common environmental toxins associated with endophyte-infected fescue grass, and that purebred Brahman yearlings can resist this aspect of fescue toxicosis.
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