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B Faye

Publications and source records attributed to B Faye.

At least 91 records · Page 5Linked to original sources
PubMed1987

[Effects of the ingestion of oxidized fish oils on hepatic microsomal enzyme activities and membrane fluidity in rats. Influence of tocopherol overload].

Rats fed a dietary peroxidized fish oil showed an increase in cytochrome P-450 content and ethoxy-coumarin deethylase (ECDE) activity in liver microsomes. Administration of DL-alpha-tocopherol led to different effects according to the extent of the peroxidation in the fish oil. In rats fed a de-peroxidized oil, the inductive effect of phenobarbital on UDP-glucuronosyltransferase (UDGPT) activity was depressed by tocopherol. By the same time, induction of P-450 and ECDE remained unchanged, that of epoxide hydrase slightly increased. By contrast tocopherol strongly potentiated the inductive effect of phenobarbital toward UDPGT activity (group I substrates) in rats fed the peroxidized fish oil. The modification of the inductive effect of phenobarbital in combination with tocopherol on UDPGT activities was concomitant with an increase in seric transaminase activity and with a reverse effect as revealed from the study of the rate of fluorescent probes penetration in microsomes. The possible toxicity of the strong dose of tocopherol is discussed.

Animals↗
PubMed1986

Kinetic constant determination of liver microsomal and purified UDP-glucuronosyltransferase after phenobarbital and 3-methylcholanthrene treatments in rats.

After induction by phenobarbital and 3-methylcholanthrene, UDP-glucuronosyltransferase involved mainly in the conjugation of planar substrates was purified. Compared to the microsomal enzyme, the purified protein exhibited less affinity towards the substrates, but the corresponding Vmaxs were increased. These results were attributed to a change in the lipid environment of the purified enzyme. The conjugation rate for 4-hydroxycoumarine was 15-45 times less than that measured for the 7-hydroxyisomer with the microsomal or the purified enzymes. Immunoprecipitation studies of the enzyme revealed that the two compounds were transformed by the same enzyme, or metabolized by two separate enzymes presenting the same antigenic site. The orientation of the hydroxyl group of planar aglycones in the active site is the determinant for the efficiency of catalysis.

Animals↗
PubMed1986

Modulation of UDPglucuronosyltransferase activity in rats by dietary lipids.

Male Wistar rats were fed for 40 d a purified diet whose lipid source (60 g/kg diet) was coconut, peanut, corn or fish (herring) oil. A low lipid (lipid-deficient) diet (corn oil, 2 g/kg diet) was also fed to some rats. There were no significant differences in final body weights of rats fed the coconut, peanut, and corn oil diets. Rats fed the fish oil diet gained less weight than those fed any other diet. However, liver weight, ratio of liver to body weight, and protein content were not affected by any of the diets. The plasma cholesterol concentration of rats fed fish oil was lower than that of the other groups of rats. This diet resulted in the highest cytochrome P-450 concentration and markedly enhanced epoxide hydrolase activity. No difference in the level in cytochrome P-450 was noted between the groups of rats fed the vegetable oils. Epoxide hydrolase activity was also significantly higher with the corn oil diet. Interestingly, only glucuronidation of group I substrates was stimulated by the fish or corn oil diets and lowered by the coconut oil diet. Liver microsomes of rats fed fish oil contained a high level of lipid peroxides; this diet greatly stimulated NADPH-dependent peroxidation. The differential stimulation of UDPglucuronosyltransferase activity towards group I substrates could be the results of a toxic action of the fish oil diet as suggested by the concomitant enhancements of epoxide hydrolase, transaminase activities and peroxide content.

Animals↗
PubMed1986

[Effects of ingestion of oxidized fish oils on membrane fluidity, and the activity of hepatic microsome enzymes in rats. Influence of vitamin A overload].

Oxidized fish oil (OFO) feeding is followed in the rat by the increase of vitamin A plasmatic level, and modifications of microsomal membranes (decrease of fluorophore ANS fixation). This inhibit the microsomal increase of cytochrome P 450, mixed function oxidase (MFO), any UDP-glucuronosyl transferases (group I) induced by phenobarbital treatment. On the other hand, vit A over load modify the microsomal structure of the opposite way (increase of ANS fixation). This effect is enlarged when OFO is added. In this case cyt P 450 is decreased. It seems that the magnification of vit. A effect is similar to increased microsomal membrane lability by oxidized fish oil addition.

Animals↗
PubMed1986

[Continuing eco-pathological survey: 11. Development of pathological frequency in dairy cow stock as a function of the stage of lactation].

The study of disease distribution observed during lactation shows that three patterns of pathology may be described: diseases for which critical period is post-partum time: we observed during the first month of lactation 32.2% of cases of clinical mastitis, 43.9% of cases of metritis, 37.9% of digestive disorders, 59.6% of appetite troubles, 23.1% of treat lesions and 52.9% of udder edema. The monthly curve squares with asymptotic function. foot disorders for which the high milk yield production period is the more sensible time (three first month of lactation). The monthly curve, near a linear decreasing, squares with a quadratic or square-root function. ovarian pathology for which frequencies depends more acute attention from breeders or clinicians to reproductive disorders than objective observation of ovarian dysfunction.

Animals↗
PubMed1986

[Continuing eco-pathological survey: 4. Demonstration of pathologic associations in dairy cow stock: herd data].

Data concerning frequencies of 17 main diseases in 59 dairy farms from continual eco-pathological survey, are analyzed by classical regression test, principal components analysis and analysis of variance. Thirty-three statistical relations (positive simple correlations) are shown. Clinical mastitis and retained placenta are associated to nine diseases each, metritis, stillbirth and non-infectious foot disorders to six, dystocia and infectious foot disorders to four, pathology of calf and abortion to three, mammary edema and appetite disorders to two. Ovarian pathology, digestive disorders and teat lesions are "isolated", being associated to only one other disease. The pathological frequencies in dairy farms seem to change in the same way, indicating the existence of common risk factors, and leading to propose a global hygienic prevention. The pathological associations allow to definite some groups of dairy farms showing one or other dominant pathological complex. In the frame of our sample of dairy farms, two groups seem to be determined: one with calving disorders and calf pathology centred on retained placenta, the other with foot disorders, infectious and metabolic troubles, centred on mastitis, as dominant diseases.

Abortion, Veterinary↗
PubMed1986

[Continuing eco-pathological survey: 5. Demonstration of pathologic associations in dairy cow stock: individual data].

The calculation of pathological association ratio (or relative risk) from two ways contingency tables, allowed to show numerous interrelationships between diseases of 1,205 dairy cows. The analysis concerns the animal during productive life, the lactation (all lactation mixed), a particular one (1st, 2nd, 3rd and more) and the beginning of productive life of cow (three first lactations). The relationships are discussed according to the level of calculation (animal, lactation, or beginning of life). There is some triangular relations: calving trilogy (dystocia-stillbirth-retained placenta), infectious trilogy (foul of the foot-metritis-mastitis), metabolic trilogy (appetite disorders-ketosis-digestive disorders), foot disorders trilogy (lameness-non infectious diseases of foot-foul of the foot). These pathological groups seem to depend from common risk factors (climate-feeding-cowshed hygiene-control of heat-age-culling policy-genetic factors-anatomical or physiological predisposition, animal size...), but, numerous interactions between groups are also shown, leading to consider pathology in farm like a complex entity.

Age Factors↗
PubMed1986

[Continuing eco-pathological survey: 6. Influence of zootechnical and space-time factors on some biochemical variables in the dairy cow].

Several hundred of blood samplings were performed on dairy cows in four French departments, from 1978 to 1982. They were used to analyse the effect of eight factors on the physiological variations of twelve biochemical variables. Only the blood withdrawal date related to calving date or milk production were able to explain more than 15% of the variance of free or total cholesterol or phospholipids.

3-Hydroxybutyric Acid↗
PubMed1986

[Continuing eco-pathological survey: 10. Variation of pathological frequency in dairy cow stock as a function of season, year and number of lactations].

The distribution of main herd diseases in course of time is studied with the season, the year and number of lactation. There is a seasonal effect for retained placenta, spring and summer being a favorable time for the increase of their frequency. Milk fever is also more frequent during summer. Out-calving pathologies are more frequent during housing time, but we do not observe any monthly variation for ovarian pathology. The age is a risk factor for milk fever and retained placenta. On the contrary, dystocia and stillbirth are more common on heifers. All the metabolic disorders and infectious diseases (mastitis-metritis) seem to be more frequent on old cows. The variations between years are interpretable with difficulty because they depend on the regularity in the quality of collected data. More, the necessity for the breeders to observe conscientiously their animals is a favouring factor for the improvement of the health status of the herd.

Age Factors↗
PubMed1986

[Continuing eco-pathological survey: 7. Epidemiological approach to postpartum mastitis in the dairy cow: descriptive study and typology of the herd].

In this study, post-partum mastitis are considered as an epidemiological entity because of their high frequency (20% of cases of mastitis are observed in the seven first days after calving). The rate increases in May-June-July and after the fourth calving. Characteristics of herds with high frequency of post-partum mastitis are the same that those from herds with high frequency of mastitis or metritis, their risk factors seeming to exert an effect on all infectious diseases. Among these factors, straw bedding quantity seems to be the more important one: a low quantity of straw, even in herds where prophylaxis against mastitis is largely used (teat dipping, dry cow therapy, disinfection), is a favouring factor for apparition of mastitis just after calving. On the contrary, use of individual towels, an abrupt dry cow therapy and a vitamin prevention during the last part of pregnancy, appear more favorable.

Animal Husbandry↗
PubMed1986

[Continuing eco-pathological survey: 8. Epidemiological approach to postpartum mastitis in the dairy cow: discriminating biochemical parameters].

To discriminate two groups of dairy cows (with or without post-partum mastitis), with blood parameters, we used discriminant analysis on two samples of dairy cows: one sample where blood was collected around parturition (15 days before and 15 days after calving); one sample where blood was collected at any time of the lactation, but with the same mean interval calving-blood collection in the two groups of animals. Blood parameters which differenciate the two groups (ill and safe) are essentially parameters of energetic metabolism i.e. glucose and 3-hydroxybutyrate. Results are discussed according to the possibility of glucose to be an indicator of energetic status.

3-Hydroxybutyric Acid↗
PubMed1985

[Effect of thyroid status on microsomal enzymes during liver regeneration in the rat].

The effects of thyroid status upon cyt. P 450 concentration and ethoxycoumarin deethylase, benzopyrene hydroxylase and UDP-glucuronosyltransferase activities in the liver microsome fraction were far more important in partially hepatectomized rats than in control animals. The partial hepatectomy simultaneously lowered the MFO enzymes activities in the hepatic microsome fraction and made them more sensitive to thyroid hormones effects.

7-Alkoxycoumarin O-Dealkylase↗