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Three trials were conducted to evaluate the effect of supplementation of a basal diet with benzoic acid or thymol or a mixture of essential oil blends (MEO) or a combination of benzoic acid with MEO (BMEO) on growth performance of turkey poults. Control groups were fed a basal diet. In trial 1, benzoic acid was supplied at levels of 300 and 1,000 mg/kg. In trial 2, thymol or the MEO were supplied at levels of 30 mg/kg. In trial 3, the combination of benzoic acid with MEO was evaluated. Benzoic acid, MEO and BMEO improved performance, increased lactic acid bacteria populations and decreased coliform bacteria in the caeca. Thymol, MEO and BMEO improved antioxidant status of turkeys. Benzoic acid and BMEO reduced the buffering capacity compared to control feed and the pH values of the caecal content. Benzoic acid and EOs may be suggested as an effective alternative to AGP in turkeys.

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In this study, the effect of probiotic supplementation via drinking water or feed on the performance of broiler chickens experimentally infected with sporulated oocysts of Eimeria acervulina (5 × 10(4)), Eimeria maxima and Eimeria tenella (2 × 10(4) each one) at 14 days of age was evaluated. Two hundred and forty 1-day-old Ross 308 male chicks were separated into eight equal groups with three replicates. Two of the groups, one infected with mixed Eimeria oocysts and the other not, were given a basal diet and served as controls. The remaining groups were also challenged with mixed Eimeria species and received the basal diet and either water supplemented with probiotic (three groups) or probiotic via feed (two groups); the probiotic used consisted of Enterococcus faecium #589, Bifidobacterium animalis #503 and Lactobacillus salivarius #505 at a ratio of 6:3:1. Probiotic supplementation was applied either via drinking water in different inclusion rates (groups W1, W2 and W3) or via feed using uncoated (group FN) or coated strains (group FC). The last group was given the basal diet supplemented with the anticoccidial lasalocid at 75 mg/kg. Each experimental group was given the corresponding diet or drinking water from day 1 to day 42 of age. Throughout the experimental period of 42 days, body weight and feed intake were recorded weekly and feed conversion ratios were calculated. Seven days after infection, the infected control group presented the lowest weight gain values, while probiotics supplied via feed supported growth to a comparable level with that of the lasalocid group. Probiotic groups presented lesion score values and oocyst numbers that were lower than in control infected birds but higher than in the lasalocid group. In the duodenum, jejunum and ileum, the highest villous height values were presented by probiotic groups. In conclusion, a mixture of probiotic substances gave considerable improvement in both growth performance and intestinal health in comparison with infected control birds and fairly similar improvement to an approved anticoccidial during a mixed Eimeria infection.

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We evaluated the effects of dietary supplementation with different preparations of probiotics on the performance of broiler chickens experimentally infected with 2 × 10(4) sporulated oocysts of Eimeria tenella at 14 days of age. Three hundred, day-old, Cobb-500 chicks, as hatched, were separated into 10 equal groups with three replicates. Two of the groups, one challenged with E. tenella oocysts and the other not, were given a basal diet and served as controls without medication. The other challenged groups were given the anticoccidial lasalocid (60 mg/kg) or Enterococcus faecium (5 × 10(8) or 5 × 10(9)cfu/kg feed), Bifidobacterium animalis (5 × 10(8)cfu/kg feed), Lactobacillus reuteri (5 × 10(8)cfu/kg feed), Bacillus subtilis (5 × 10(8)cfu/kg feed), or a multi-species probiotic mix at 5 × 10(8) or 5 × 10(9)cfu/kg feed, respectively. The trial lasted 6 weeks. Individual body weight, feed intake per pen and feed conversion ratio values were recorded weekly, along with the extent of bloody diarrhea, excreta oocyst numbers and bird mortality. Caecal lesions were assessed and intestinal samples were taken for histopathological and bacteriological evaluation from ileum and caecum. Overall growth performance of chickens fed the multi-species probiotic mix at both levels was higher (P<0.05) compared to the infected control. Overall oocyst shedding was lowest (P<0.05) in the lasalocid supplemented group. Villous height was higher (P<0.05) in Bacillus supplemented groups compared to infected controls. The Lactobacillus supplemented group had the highest (P<0.05) numbers of both Lactobacillus and Bifidobacterium in ileum and caecum. In conclusion, dietary probiotics are promising for further investigation on improving intestinal health and growth performance of broiler chickens experimentally challenged with E. tenella.

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In this study, we evaluated the intestinal morphology and bacteria populations in broiler chickens fed for six weeks diets that contained different amount of the mushroom Agaricus bisporus. Ninety day-old female chicks were randomly divided into three dietary treatments, each with three replicates kept in floor pens and fed a basal diet supplemented with the dried mushroom at levels of 0, 10 or 20 g/kg fresh feed. Feed and water were offered to birds ad libitum. The morphological examinations of the intestine were carried out on 1-cm long excised segments from duodenum, jejunum and ileum. The populations of total aerobes, total anaerobes, Lactobacilli spp., Bifidobacteria spp., Escherichiacoli, Bacteroides spp. and Enterococci were enumerated in ileum and caecum by conventional microbiological techniques using selective agar media. The results of the study showed that dietary mushroom supplementation did not significantly affect intestinal morphology at either level of inclusion. Morphometrical parameters of depth of duodenum, jejunum and ileum crypt and height of villi revealed no differences amongst dietary treatments. In the ileum, Lactobacilli spp. were higher in birds supplemented at the level of 20 g/kg compared to controls; however, other measurements of bacteria loads were similar amongst the three dietary treatments. In the caecum, Lactobacilli spp. and Bifidobacteria spp. loads were higher in birds supplemented at either level of inclusion compared to control birds, although these did not differ between the two levels of supplementation. In conclusion, dietary mushroom supplementation may beneficially affect intestinal health of broiler chickens.

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AIM: A small number of left internal thoracic artery (LITA) grafts are occluded at 3 years after the operation or show more than 50% stenosis of the lumen. The purpose of this study is to examine factors related to the morphology of the wall and to the function of the cell population of LITA grafts before implantation, in order to evaluate their quality and the viability, in a follow-up examination. METHODS: Fifteen LITA grafts were examined with light microscopy, for their morphology, endothelial cell coverage, apoptosis and cell proliferation, scanning electron microscopy and transmission electron microscopy. RESULTS: Increase of the thickness of the intima (14.21+/-1.28 mm), mean thickness of media 160.37+/-11.97 mm, detachment of intima from media, presence of foam cells in the media, low endothelial coverage (40.638+/-16.864), increase of apoptosis in intima (46.38+/-13.46), sub-intima (29.3+/-8.54), media (34.91+/-6.05) and adventitia (40.21+/-5.36), blood cells penetration of the intima through disruptions between endothelial cells are findings of LITA grafts before implantation. Cell proliferation was not detected in the wall of any graft. Follow-up examination 6 months and 2.5 years after the operation showed normal function of LITA grafts. CONCLUSIONS: Besides of the wall injury and the initiated atherosclerotic lesions, LITA grafts are well functioning at the time of the follow-up examination. Maybe our findings are related to the later occlusion of the referred in the literature small number of LITA grafts.

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BACKGROUND: Twenty percent of the long saphenous vein (LSV) grafts that are employed as coronary bypass conduits occlude during the first year after the operation. The aim of this study was to evaluate the morphological parameters of the LSV grafts before implantation as predictors for the early occlusion of the grafts. METHODS: Forty-two samples of LSV grafts were examined via light, transmission electron, and scanning electron microscopy and evaluated clinically and by angiography at 6 months and 2 years after the operation. Morphological parameters were statistically analyzed and examined for their significance on the viability of the vein grafts. RESULTS: Six (14.28%) of the examined grafts occluded within the first 6 months after the operation, and 11 grafts (26.19%) occluded within the first 2 years. The grafts that occluded at 6 months were characterized by thick intima (mean value, 206+/-32.29 vs. 67.44+/-10.17 in the group functioning normally and 98.42+/-34 in the group occluded within 2 years), low endothelial coverage (22.7+/-4.04 vs. 64.61+/-2.89 and 26.06+/-1.78 in the corresponding groups), and narrow lumen (46.73+/-9.69 vs. 527.18+/-45.78 and 204.26+/-16.5 in the corresponding groups). The presence of foam cells, edema, calcification, neovascularization, and thrombus in the lumen of the veins is frequently observed in the wall of the occluded vein grafts, whereas fibrosis does not seem to be related. CONCLUSIONS: LSV grafts with low endothelial cell coverage, stenosis of the lumen, and thick walls are at an increased risk of developing intrawall lesions that lead to early graft failure.

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A well-established rabbit model of enteropathogenic E. coli (EPEC) disease was used to examine whether vitamin E (VE) nutritional supplementation had an effect on the pathological changes induced in the bowel by EPEC. Quantitative methods were used to evaluate the influence of VE on bacterial colonization, intestinal mucosal architecture and inflammation, and intestinal epithelial proliferation and apoptosis. VE did not affect EPEC colonization and did not give significant protection against EPEC-induced changes and diarrhoea. Although VE had no effect on the EPEC-related increase of enterocyte apoptosis, it clearly contributed to an acceleration of epithelial cell proliferation in the ileal crypts. This finding may explain why ileal morphometry undertaken in this study showed that VE ameliorated somewhat the effects of EPEC on intestinal mucosal architecture. Quantitative studies on inflammatory cells in the intestinal mucosa revealed that VE nutritional supplementation resulted in an increased neutrophilic and mononuclear inflammatory cell response to EPEC infection, which did not contribute, however, to the clearance of infection.

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BACKGROUND AND OBJECTIVE: We conducted this study in order to evaluate the potential myotoxic effects of ropivacaine after single injection in rats and the time-course of the possible damage. METHODS: One hundred and twenty-eight male Wistar rats were allocated to four different groups. The first three groups received intramuscular injections with ropivacaine 0.75%, ropivacaine 0.5% and normal saline, respectively, into the right tibialis anterior muscle. The fourth group received needle puncture without injection. Eight rats from each group were sacrificed 2, 4, 7 and 30 days after injection. Samples were blindly examined under light microscope for evidence of myotoxicity, scored as 0 = no damage to 3 = myonecrosis and statistically analysed. Samples obtained 7 days after injection were also examined under transmission electron microscope. RESULTS: Ropivacaine 0.75% and ropivacaine 0.5% caused extensive destruction to muscles fibres, compared to saline or needle on days 2, 4 and 7. Statistically significant differences were found in muscle damage by drug injections among all groups except for saline vs. needle groups. Thirty days after injections all sample appearances had returned to normal. CONCLUSIONS: Ropivacaine after single intramuscular injection caused reversible muscle damage in a dose-dependent manner.

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