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1.
An. acad. bras. ciênc ; 90(1): 219-229, Mar. 2018. tab
Article de Anglais | LILACS | ID: biblio-886877

RÉSUMÉ

ABSTRACT This study was done to discover any beneficial effect of a medicinal mushroom Agaricus brasiliensis extract on the honey bee. Firstly, a laboratory experiment was conducted on 640 bees reared in 32 single-use plastic rearing cups. A. brasiliensis extract proved safe in all doses tested (50, 100 and 150 mg/kg/day) irrespective of feeding mode (sugar syrup or candy). Secondly, a three-year field experiment was conducted on 26 colonies treated with a single dose of A. brasiliensis extract (100 mg/kg/day) added to syrup. Each year the colonies were treated once in autumn and twice in spring. The treatments significantly increased colony strength parameters: brood rearing improvement and adult population growth were noticed more often than the increase in honey production and pollen reserves. These positive effects were mainly observed in April. In conclusion, A. brasiliensis extract is safe for the bees and helps maintaining strong colonies, especially in spring.


Sujet(s)
Animaux , Abeilles/effets des médicaments et des substances chimiques , Agaricus/composition chimique , Miel , Pollen/physiologie , Saisons , Facteurs temps , Abeilles/physiologie , Reproductibilité des résultats , Croissance démographique , Statistique non paramétrique , Phénomènes physiologiques nutritionnels chez l'animal/effets des médicaments et des substances chimiques
2.
An Acad Bras Cienc ; 90(1): 219-229, 2018.
Article de Anglais | MEDLINE | ID: mdl-29424386

RÉSUMÉ

This study was done to discover any beneficial effect of a medicinal mushroom Agaricus brasiliensis extract on the honey bee. Firstly, a laboratory experiment was conducted on 640 bees reared in 32 single-use plastic rearing cups. A. brasiliensis extract proved safe in all doses tested (50, 100 and 150 mg/kg/day) irrespective of feeding mode (sugar syrup or candy). Secondly, a three-year field experiment was conducted on 26 colonies treated with a single dose of A. brasiliensis extract (100 mg/kg/day) added to syrup. Each year the colonies were treated once in autumn and twice in spring. The treatments significantly increased colony strength parameters: brood rearing improvement and adult population growth were noticed more often than the increase in honey production and pollen reserves. These positive effects were mainly observed in April. In conclusion, A. brasiliensis extract is safe for the bees and helps maintaining strong colonies, especially in spring.


Sujet(s)
Agaricus/composition chimique , Abeilles/effets des médicaments et des substances chimiques , Miel , Phénomènes physiologiques nutritionnels chez l'animal/effets des médicaments et des substances chimiques , Animaux , Abeilles/physiologie , Pollen/physiologie , Croissance démographique , Reproductibilité des résultats , Saisons , Statistique non paramétrique , Facteurs temps
3.
Int J Med Mushrooms ; 17(4): 321-30, 2015.
Article de Anglais | MEDLINE | ID: mdl-25954958

RÉSUMÉ

The aim of this investigation was to evaluate the possible protective activity of Agaricus brasiliensis (=A. blazei sensu Murrill) ethanol extract against thymol-induced DNA damage in human lymphocytes. Before we studied the possible interaction of thymol and A. brasiliensis extract, each component was tested in the comet assay. Thymol significantly increased DNA damage in human lymphocytes at higher concentrations (20, 50, 100, 150, and 200 µg/mL), whereas no genotoxic effect of A. brasiliensis ethanol extract was observed. In simultaneous treatment with thymol (200 µg/mL) and A. brasiliensis ethanol extract (50, 100, 150, and 200 µg/mL), the latter failed to reduce a thymol-induced DNA damaging effect regardless of the applied concentrations. To confirm that thymol induces DNA damage via reactive oxygen species, we performed cotreatment with quercetin. Cotreatment with quercetin (100 and 500 µmol/L) significantly reduced DNA damage caused by thymol (200 µg/mL), indicating that thymol exhibits genotoxicity mainly through induction of reactive oxygen species.


Sujet(s)
Agaricus/composition chimique , Antigènes fongiques/toxicité , Altération de l'ADN/effets des médicaments et des substances chimiques , Lymphocytes/effets des médicaments et des substances chimiques , Mutagènes/toxicité , Thymol/toxicité , Adulte , Antigènes fongiques/isolement et purification , Test des comètes , Humains , Mâle , Espèces réactives de l'oxygène/antagonistes et inhibiteurs , Espèces réactives de l'oxygène/toxicité
4.
Acta sci. vet. (Impr.) ; 41: Pub. 1128, 2013. tab
Article de Anglais | VETINDEX | ID: biblio-1372417

RÉSUMÉ

Background: Production diseases, such as those associated with improper nutrition or management are common in transitional high-yielding dairy cows. The diseases listed in this include: the fat liver syndrome, ketosis, oxidative stress, laminitis, mastitis, milk fever, retained placenta, metritis and infertility. The diseases occur mainly around calving. They are all interrelated and form the so-called periparturient disease complex. The term transition is to underscore the important physiological, metabolic, nutritional and endocrine changes occurring in this time frame. Diagnosing liver lipidosis and susceptibility of ketosis in dairy cows may include liver biopsy or ecography, but a less invasive and more economical analytical method may be the measurement of blood biochemical metabolites. The objective of the present study was to determine a relationship among blood indicators of hepatic function and lipid content in the liver during transitional period in high-yielding dairy cows. Materials, Methods & Results: Late pregnant and calved cows (n = 40) were selected from a Holstein dairy herd and allocated to four groups: a late pregnant cows (n = 10) from day 15 to day 5 before calving; late pregnant cows (n = 10) from day 4 to day 1 before calving; clinically puerperal healthy cows (n = 10) and clinically ketotic puerperal cows (n = 10). Liver and blood samples were taken from all cows. The blood metabolites concentrations were determined by photometric methods using a Cobas Mira automatic analyzer. Liver specimens were histopathologically analyzed for lipid contents using a freezing microtome. The statistical analysis of the obtained data was carried out by ANOVA-procedure. The results of present investigation have shown that the lipid content in the liver and the blood non-esterificed fatty acids, ß-hydroxybutyrate, total bilirubin concentrations and the AST activities were significantly higher (P < 0.05) as well the blood glucose, total cholesterol, triglycerides and albumin concentrations were significantly lower (P < 0.05) in puerperal ketotic cows as compared to the values of these parameters in the blood of healthy cows in the transition period. Discussion: Liver biopsy is the only reliable method to determine severity of fatty liver in dairy cattle in the transitional period. Blood, urine and milk metabolites or blood enzyme activity have been proposed as diagnostic tools. This investigation demonstrated that in healthy transitional cows a mild fatty infiltration occurred in liver during the late pregnancy and early lactation. The histopathological examination showed a moderate to severe degree of fatty liver in ketotic cows. The lipomobilisation markers, serum BHB and NEFA concentrations, were markedly enhanced in puerperal ketotic cows. However, liver steatosis compromised hepatocyte metabolism, leading to signifi cantly weaker circulating concentrations of glucose, TG and total cholesterol, and induced some cellular lesions as evidenced by significant increases in the serum bilirubin concentrations and in the AST enzyme activities in puerperal ketotic cows. All these biochemical metabolites may be used as important biochemical indicators in the determination of the functional status of the liver in high-yielding dairy cows during the transition period.


Sujet(s)
Animaux , Femelle , Bovins , Lipidoses/médecine vétérinaire , Tests de la fonction hépatique/médecine vétérinaire
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