Effect of thymol on the broiler chicken antioxidative defence system after sustained dietary thyme oil application.

1. The purpose of this study was to examine if the concentration of thymol as the main compound of Thymus vulgaris essential oil (TEO) influenced the antioxidant defence system in broilers. 2. Twenty-four broiler chickens were randomly divided at the day of hatching into three dietary treatment groups (0%, 0.05% and 0.1%, w/w TEO) with eight birds in each and were fed until four weeks of age. 3. Thymol content in plasma, duodenal wall and breast muscle significantly increased when 0.1% of thyme oil was added to the diet (P < 0.05). Thymol concentration in plasma significantly correlated with levels measured in the duodenal wall and feed (rs = 0.7857, P < 0.05; rs = 0.7647, P < 0.05). Superoxide dismutase (SOD) activity increased, and malondialdehyde (MDA) concentration decreased significantly (P < 0.05) in blood from chickens fed 0.1% TEO supplementation. Although the thymol concentration did not significantly decrease MDA amounts in breast muscle, a declining trend was observed. 4. The trial data confirmed the efficient absorption of thymol from the digestive tract into the systemic circulation, but only traces were found in breast muscle. Thymol content was sufficient for expressing its antioxidant properties in blood, but its low content in breast muscle was insufficient to significantly affect lipid oxidation and fatty acid composition.

Fortification of dried distillers grains plus solubles with grape seed meal in the diet modulates methane mitigation and rumen microbiota in Rusitec.

The role of dried distillers grains plus solubles (DDGS) and associative effects of different levels of grape seed meal (GSM) fortified in DDGS, used as both protein and energy sources in the diet, on ruminal fermentation and microbiota were investigated using rumen-simulation technique. All diets consisted of hay and concentrate mixture with a ratio of 48:52 [dry matter (DM) basis], but were different in the concentrate composition. The control diet contained soybean meal (13.5% of diet DM) and barley grain (37%), whereas DDGS treatments, unfortified DDGS (19.5% of diet DM), or DDGS fortified with GSM, either at 1, 5, 10, or 20% were used entirely in place of soybean meal and part of barley grain at a 19.5 to 25% inclusion level. All diets had similar DM, organic matter, and crude protein contents, but consisted of increasing neutral detergent fiber and decreasing nonfiber carbohydrates levels with DDGS-GSM inclusion. Compared with the soy-based control diet, the unfortified DDGS treatment elevated ammonia concentration (19.1%) of rumen fluid associated with greater crude protein degradation (~19.5%). Methane formation decreased with increasing GSM fortification levels (≥ 5%) in DDGS by which the methane concentration significantly decreased by 18.9 to 23.4 and 12.8 to 17.6% compared with control and unfortified DDGS, respectively. Compared with control, unfortified DDGS decreased butyrate proportion, and GSM fortification in the diet further decreased this variable. The proportions of genus Prevotella and Clostridium cluster XIVa were enhanced by the presence of DDGS without any associative effect of GSM fortification. The abundance of methanogenic archaea was similar, but their composition differed among treatments; whereas Methanosphaera spp. remained unchanged, proportion of Methanobrevibacter spp. decreased in DDGS-based diets, being the lowest with 20% GSM inclusion. The abundance of Ruminococcus flavefaciens, anaerobic fungi, and protozoa were decreased by the GSM inclusion. As revealed by principal component analysis, these variables were the microorganisms associated with the methane formation. Grape seed meal fortification level in the diet decreased DM and organic matter degradation, but this effect was more related to a depression of nonfiber carbohydrates degradation. It can be concluded that DDGS fortified with GSM can favorably modulate ruminal fermentation.

[Use of copper oxide wire particles (Copinox) for the prevention of congenital copper deficiency in a herd of German Improved Fawn breed of goat]. / Einsatz von Kupferoxid-Boli (Copinox) zur Prävention des kongenitalen Kupfermangels in einer Herde Bunter Deutscher Edelziegen.

In a herd of German Improved Fawn breed of goat in the year 2000 neonatal kid losses due to congenital copper deficiencies were observed. To clarify the problems and to prevent losses in the next breeding season serum copper levels of 10 dams and four control Boer goats were investigated at four time points during one year. Additionally ten kids of the following year were sampled and the serum copper levels were studied. Immediatly after parturition and 8 weeks later the dams showed low serum copper levels (10.4 +/- 11.1 micromol/l, 5.7 +/- 2.9 micromol/l resp.). At the end of the pasture season an increase of serum copper could be measured (19.3 +/- 16.0 micromol/l). To prevent enzootic ataxia due to congenital copper deficiency, the dams were treated with copper oxide wire particles in the next late gestation. At this time point serum copper concentrations started to decrease (18.5 +/- 8.4 micromol/l). The re-examination 3 month later demonstrated an increase of the serum mean copper concentrations up to 23.4 micromol/l in the dams and to 16.2 micromol/l in the kids. The serum copper levels were significantly higher compared to the levels the year before. Big variation of the serum copper levels in the control Boer goats occurred during the year, but no clinical symptoms of copper deficiency could be observed. The copper levels in the grass and soil samples were 6.8 mg/kg and 0.2 mg/kg dry substance, respectively. A secondary copper deficiency based on cadmium could be excluded through the low levels of soil samples. The contents of sulphur and molybdenum were not determined. The results indicate that the German Improved Fawn breed of goats suffered from a primary copper deficiency due to the inefficient mineral supplementation. The administration of Copinox in the last third of the gestation leads to a continious raising of the copper concentrations in the serum and is suited to prevent ataxia due to congential copper deficiency in neonatal kids.

GC analysis of essential oils in the rumen fluid after incubation of Thuja orientalis twigs in the Rusitec system.

Methods for the chemical analysis of toxic plant substances in the rumen of ruminants are of importance for the diagnosis of intoxications with poisonous plants. The present work establishes a method to estimate monoterpene components of the essential oil of thuja (Thuja orientalis, Cupressaceae) in these types of samples. Alpha-thujone, which is regarded as the toxic principle, is present at a concentration of 50-60% in the essential oil. The rumen simulation technique (Rusitec) was used to simulate natural digestion. Chopped twigs of thuja were subjected to rumen content in a closed container with an overflow device. The flow of saliva was simulated by the continuous addition of a buffer solution. Samples for analysis were taken from the overflow at 24 and 48 h. A further sample was taken from the remaining liquid fraction of the rumen content in the container at 48 h. The essential oils were extracted with hexane and concentrated. A quantitative determination was done by capillary gas chromatography. Together in the three fractions analysed this resulted in total mean recoveries of 6.8% for alpha-thujone, 5.3% for beta-thujone, 18.9% for fenchone and 27.8% for camphor. The observation that the thujones were recovered to a lesser extent than other oil components is evidence of their fast decomposition in the rumen medium. Under these circumstances the calculated detection limit is 100-200 g thuja twigs in cows with rumen volumes of 60-100 litres. The main essential oil degradation products found in the rumen fluid of all three fractions in the Rusitec system were discovered to be iso-3-thujanol, neo-3-thujanol, carvomenthol and carvomenthone.

Variability in chemical constituents in Petasites hybridus from Austria.

Petasites hybridus (Asteraceae), butter bur, is an ancient medicinal plant with spasmolytic sesquiterpene esters. Two chemotypes, the petasine and the furanopetasine chemotype, occur in Austria. The first one is considered as pharmaceutically useful due to its spasmolytic constituents, but it is restricted to the northern parts of the Alps. This use, however, is impaired by the presence of low amounts of toxic pyrrolizidine alkaloids (PA), mainly senecionine and intergerrimine. PA are usually concentrated in the metabolically active parts of the complex rhizome which are the thickenings just below the leaves. They are also present in flower stalks but are almost absent in leaf buds, the petioles and the leaf blades. The alkaloids showed a great variability within and between populations; the values recorded ranged from less than 2 to 500mgkg(-1) PA, median PA of 77 populations varied from 2 to 191mgkg(-1) in the rhizomes. In nearly 25% of the samples analysed the PA content was below 10mgkg(-1), another 25% had between 10 and 20mgkg(-1) PA. Histograms of PA concentrations in a population often showed a distinct skewness toward lower alkaloid contents. Alkaloid content was independent of sesquiterpene chemotype. The seasonal influence on PA content of rhizomes was little in comparison to the variability within the population or within the rhizome itself. Nevertheless, when comparable rhizome parts within a population were considered, the PA content may remain stable over several years. Although plants totally free of PA could not yet be found, it is possible to select populations low in alkaloids. Several populations of the petasine chemotype containing less than 10mgkg(-1) in the rhizomes could be found in the area investigated.

A competitive enzyme immunoassay for the pyrrolizidine alkaloids of the senecionine type.

We developed an immunoassay with antibodies against retrorsine to detect the closely related senecionine, the main alkaloid in various Asteraceae. Sensitivity is about 23 pg (68 fmol) for senecionine. Cross reactivity of monocrotalin, retrorsine N-oxide, senkirkine (< 0.1%), and seneciphylline (3.6-34.5%) was resolved. The alkaloid content in leaves of Petasites hybridus (Asteraceae) was determined to be 3.86 ppm, calculated as senecionine, which was far less than in rhizomes (104.8 ppm). Additionally, we proved specificity by taking immunograms from different parts of Petasites hybridus. The test is a suitable tool for assessing the toxic potential of medicinal plants containing senecionine.

[Toxic effects in rabbits after immunization against the pyrrolizidine alkaloid retrorsine]. / Toxische Effekte beim Kaninchen durch Immunisierung gegen das Pyrrolizidinalkaloid Retrorsin.

Six rabbits were immunized against the pyrrolizidine alkaloid retrorsin, conjugated to bovine serum albumin. Seven i.v. inoculations were distributed over a period of half a year. The total antigen dose differed between animals. Towards the end of the experiment all animals (except 2 receiving the lowest antigen dose) suffered from apathy, anorexia and loss of body weight. Pathologically these symptoms correlated well with liver cirrhosis, gradually dependent on the total antigen dose. Blood-chemical parameters were disparate and contradictory.