George W. Bush
Ground was broken on the clubhouse building in mid-August Dès le début de son mandat, il bénéficie d'une majorité républicaine au Congrès des États-Unis. Dans son discours annuel sur l'état de l'Union le 31 janvier , George W. Other orally active oestrogens include ethynyl-oestradiol, a more slowly metabolized derivative of the true hormone, with higher activity.
A Story Bigger Than Texas
These gains represented a saving of about 23 billion kg of total digestible nitrogen per year, the volume of milk produced remaining relatively constant. L'association homosexuelle républicaine Log Cabin Republicans se désolidarise de sa candidature lors de l'élection présidentielle de à cause notamment de son hostilité au mariage homosexuel d'autant plus que Bush en soutient l'interdiction constitutionnelle. Bush défend son bilan et fait ses dernières recommandations , Le Monde , 16 janvier Cette décision se heurte à un congrès et une opinion publique hostile et majoritairement sceptique par cette démarche [ 78 ]. Number of animals treated 1 Steers Heifers. Extracts in the organic and aqueous phase mostly contained unchanged DES in the free and conjugated form respectively
Practice varies with management systems. Animals may be implanted at live weights from to kg. Depending upon the age and weight at the time of implantation, the animals are either slaughtered at the end of this first period, or fed for an additional period, either without further treatment or after a second implant to act for another 80 to days.
Most types of implants in use are not removable, but removable types have recently been tested and their effects described When tested in steers, no reduction in performance was recorded when the implants were withdrawn 32 and 39 days before slaughter.
Implantation is subcutaneous, usually at the base of the ear, thus eliminating the risk that residues of the implantation site will be present in edible tissue. In veal calves, hormone treatment may begin at a body weight of about 65 kg, the animals being slaughtered at about kg. The most extensive studies of the effects of hormones on growth and FCE have been carried out on steers, under strictly controlled conditions as well as in the field.
Hexoestrol implants, usually in doses of 30 to 60 mg, have been shown in numerous experiments to lead to considerable improvement in growth rate and FCE 23, 24, 25, 26, 27, 28, In 19 trials carried out over the years on experimental husbandry farms in the UK, the overall average increase in gain produced by 45 or 60 mg hexoestrol implants was 0. Zeranol implants , usually at 36 mg, have consistently improved gain as well as FCE 20, 23, 24, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, In a series of 21 UK trials over several years, the average response to zeranol implants alone was an increase in daily gain of 0.
Only in one trial was there no response Similar results have been obtained in Ireland cit. Positive effects on gain in steers have been observed under a variety of experimental conditions, under controlled feeding, on ad lib feeding of standardized rations, and on pasture.
TBA implants administered alone at a dose of mg have also had positive effects on growth 23, 24, 25, 26, 27, 29, 37, 40, 41 , even if combination with an oestrogen has yielded better responses vide infra.
In a series of 8 trials in the UK, the average additional daily gain amounted to 0. Similar results have been reported from Ireland cit. A number of trials have been carried out with implants containing two hormones. The combination of an oestrogen with an anabolic steroid, or with progesterone, has met with the greatest responses.
Hormone preparations have also been tested in combination with substances such as monensin, which increase FCE by promoting propionic acid formation in the rumen. Results have varied from no effect 38, 52 to marked additional gain Reimplantation, tested under various forms of management with varying results 25, 26, 32, 36, 52, 56, 57, 58 , has not gained general acceptance.
In addition, double implantation increases the possibility of exceeding the optimum dose rate and the chance of deleterious side effects occurring. The evidence for highly significant positive effects on the growth rate and FCE of steers is thus beyond dispute, the most marked effects being provoked by implants combining an oestrogen with an androgen of high anabolic activity. Since the entire male animal produces its own anabolic androgen, testosterone, an effect of additional hormones similar to that for steers is not to be expected.
The number of trials with bulls is also limited. Recent trials with beef-producing heifers have mostly been based on the use of an androgen, although oestrogens have been tested, alone or in combination. Thus, zeranol has been reported to increase gain 62, 63 , while in other trials no response has been observed 37, In other trials, combinations of an oestrogen with TBA 68 or testosterone 62 have yielded significant growth responses. Trials have mainly concerned wether lambs, and positive effects of hormonal treatment have been reported using DES 69 , hexoestrol 71 and zeranol 72, 73 , although other reports have indicated that zeranol yields no significant effects 74, In general, however, the results obtained in sheep thus far do not warrant the same clear-cut conclusions as for steers and heifers.
There is little evidence that existing hormonal preparations influence the growth rate and FCE to an extent that would be interesting from a practical point of view. In poultry, redistribution of fat in the body is a known effect of oestrogens. Recent research indicates improved growth rate and FCE using androgens in young male and female turkeys 13, cit. Reported side effects of hormone treatment for growth stimulation are few and generally concern the use of oestrogens in steers.
Changes in body conformation such as feminization and raised tail-heads were described as early as Similarly, bulling has occurred with increased frequency 57, , , although in most animals it is limited to the first few days after implantation However, it has been reported from Kansas that 2. In a study of the effect of reimplantation of oestrogens in steers, all animals were given a 30 mg DES implant at a live weight of kg, and then reimplanted 91 days later, with either 30 mg DES or Synovex S.
Following the second implant, the frequency of the steer-buller syndrome was 1. The steer-buller syndrome is a special problem in feedlots. No reliable explanation of how the growth-promoting hormones act has yet been furnished.
Some observations indicate an indirect influence through changes in the balance of endogenous hormones. However, others have found no such effect 49, 60, 67, 77, Recent experiments indicate that DES reduces the rate of muscle catabolism in steers As regards the anabolic androgens, evidence exists indicating competition with glucocorticoids for receptor sites on the muscle cell membrane.
Since glucocorticoids have a catabolic effect on tissues, their displacement from muscle cells would reduce catabolism. The significance of these findings is not yet clear. For a fuller discussion of possible mechanisms of action of the hormones, see references 2, 27 and Any discussion of possible health hazards connected with the use of hormones in animal production must take into account the normal occurrence of hormones and their metabolites in body fluids and tissues, and the fact that the levels of these hormones vary greatly, according to the physiological state of the animal.
Thus, oestrogen levels in the blood of female farm animals may vary from a few pg up to 5—6 pg per ml plasma 6. As to males, the plasma of stallions and entire male pigs contains high levels of oestrogens, although mainly in the conjugated form. More recently, reliable data have also become available concerning concentrations in edible tissues; some of these are presented in Table 2. For the sake of comparison, levels of oestrogen activity normally present in products of plant origin widely used in human nutrition are included.
The general patterns of metabolism and elimination of endogenous hormones in farm animals have been outlined Progesterone is partially converted to androgens before excretion. The faecal route of elimination dominates in ruminants, while in the pig urinary excretion is more important. After repeated injections of progesterone to cows and steers over 2 to 3 weeks followed by 14 C-progesterone for 2 to 5 days, the animals were slaughtered 2 to 3 hours after the last injections.
Activity levels were 2 to 7 times higher in the fat, 3 times higher in the kidneys, and 13 times higher in the liver than in the muscle. Cooking or frozen storage did not affect the nature or quantity of metabolites In fat the levels were 3 to 5 times higher.
Oestradiol was completely conjugated during absorption and its first passage through the liver. Some conversion to oestrone took place The metabolism of DES in food-producing animals has been reviewed recently The substance seems to be eliminated to a large extent in unaltered form.
After oral administration of 14 C-DES to beef cattle, Free radioactivity was almost completely associated with unchanged DES. At the time of slaughter, levels were less than 0.
In a study in steers implanted with 14 C-DES, on day after implantation radioactivity in muscle was not distinguishable from background. It was above background in spleen, lung, adrenal glands and kidney, but less than levels corresponding to 0. In a similar study on steers, days after implantation, levels in liver, kidney, lungs and salivary glands were in the range of 0. In a recent study of DES metabolism in rhesus monkeys and chimpanzees, most of the substance was excreted with the urine.
Extracts in the organic and aqueous phase mostly contained unchanged DES in the free and conjugated form respectively Current evidence indicates that the oxidative metabolism of DES leads to at least three compounds that may have cytotoxic or mutagenic activity , but these have not been identified as DES metabolites in ruminants, but in the mouse. Using a gas chromatographic method with a sensitivity limit of 20 ppb, no residues of zeranol could be detected in edible tissue from cattle slaughtered 65 days following implantation of 36 mg, or from lambs 40 days following implantation of 12 mg In another study, tritiated zeranol was implanted in cattle as part of mg doses.
Skeletal muscle obtained 10, 30 and 50 days following implantation contained no detectable residual activity This confirms previous results based on the use of 14 C-labelled zeranol Another metabolite of TBA in cattle is the keto compound, analogous to oestrone; quantitatively it appears to be of very little importance.
Other metabolites occurred in extremely small quantities in cattle , Similar findings have been reported in studies based on the use of implants cit. The major route of excretion is by faeces. Much work has been devoted to the development of sensitive methods of detecting hormone residues in meat from hormone-treated animals. As regards compounds given orally, it should in principle be possible to realize claims of zero-tolerance residue levels, by selecting the proper withdrawal time.
During recent years, the use of implants has, however, gained in importance. While removable implants have been tested in steers, with no decrease in performance when withdrawn 32 and 39 days before slaughter , the wide use of non-removable implants makes residue studies important.
Determination of normal levels of endogenously produced natural hormones is also important, to enable risk evaluation to be carried out in realistic terms. Several residue studies have been made of synthetic as well as natural compounds, mainly in cattle. In the latter case there was almost complete overlap between values for untreated and treated steers after days Zeranol implants have so far not left detectable residues in edible tissue 99, , Most studies of androgens have concentrated on TBA.
Results based on radio-immunoassay of extracts or on radioactivity measurements 88, , , , , , have indicated levels in edible tissue of the order of 1 ppb or below. In a recent study using implants containing tritiated TBA in heifers, it was found that when slaughter took place 60 days after implantation, the major proportion of tritium-containing residues was not extractable with organic solvents.
This suggests that the major part of the residues after TBA implantation occurs in a non-extractable, possible covalently bound form in tissues Residue levels of gestagens have been also measured, in connection with their use as growth stimulants. Residues of melengestrol acetate used as a feed additive in daily doses of 0. Table 3, which provides data on normal levels of these hormones in certain dairy foods, shows that some foods represent hormone sources vastly richer than meat from hormonetreated animals.
Based on these values, and averages for consumption of various foods, the relative contribution of meat from hormone-treated animals to the total consumption of hormones has been calculated on the assumption of proper use of the hormones see Table 4. It is clear that in most cases the contribution from meat of treated animals is insignificant when hormones have been properly used, and must be considered to be biologically without impact. This becomes even more evident when seen in relation to normal endogenous hormone production in man, as illustrated in Table 5.
It will be seen that even for oestrogens, the hormones considered the greatest risk, the maximal contribution from meat assuming proper use of the hormones is less than 0. Thus far the discussion has been limited to the natural hormones. For synthetic substances the situation may be different. But again, considering the very low residue levels found when hormones have been properly used, the question may be raised whether the risk to the consumers is being grossly overestimated.
Relative contribution of meat from hormone-treated steers to total hormone intake via food per cent. Contribution of hormones from hormone-treated steers relative to total daily hormone production in man 1 per cent. The improvement in FCE which usually accompanies the increase in gain adds to the economic benefits, and at the same time makes possible greater production of edible protein per unit energy used, and this in itself is of importance in a world lacking in protein supplies.
Few analyses of the economic advantages of using hormones as growth stimulants appear to have been made. Decline of Spanish Rule: Though it started as a mission, San Antonio de Valero was now secularized, and the Spanish military occupied the old mission compound and converted it into a frontier outpost and military garrison. The soldiers of the Alamo Company, named for their hometown Alamo de Parras south of the Rio Grande, shifted their allegiance to the newly formed independent nation of Mexico.
The Alamo, now a fortress under the command of year-old William Barret Travis, came under siege by dictator Santa Anna. He ordered the pre-dawn attack on March 6, in which Texians, Tejanos, Americans and Europeans sacrificed themselves to stop a tyrant. But the fighting did not end there. Mexico refused to give up its claim to Texas as well as the additional territory claimed by the new Republic, and launched military attacks on Texas several times in the ensuing years.
The Alamo remained a vital military garrison protecting San Antonio and supplying border forts from Mexican incursion and Indian attacks. The Army Moves In: San Antonio de Béxar and the Alamo greatly benefitted from annexation and statehood.
Centrally located and vital to Texas, San Antonio was already seen as an important civic and military asset. The Alamo became a U. Army outpost and depot. It was during this period that the Army added the Alamo's famous bell-shaped top.
Army departed the Alamo and established Fort Sam Houston to replace it in
Imsges: w rencontre
Les grands électeurs se répartissent ainsi: Bush concernant sa gestion de la guerre d'Irak ont commencé à basculer en juin et sont devenus négatifs à partir du mois de septembre Cette opposition géo-politique s'explique notamment par le profil sociologique des habitants de la plupart des grandes villes qui correspond ainsi à celui de l'électeur démocrate traditionnel prépondérance des célibataires, des femmes, et des minorités ethniques alors que la sociologie des banlieues le borough de Staten Island à New York ou le comté d'Orange près de Los Angeles par exemple et des villes rurales Charleston en Caroline du Sud correspond à celui de l'électeur républicain hommes blancs, couples mariés avec enfants.
On the evening of November 22, , Sen. Whatever management system is adopted, effective disease control is essential for productivity.
Average increase in daily gain kg 2 Steers Heifers. Depending upon the age and weight at the recnontre of implantation, the animals are either slaughtered at the end of this first period, or fed for an additional period, either without further treatment or after a second implant to act for another 80 to days. Morgan CompanyCharles D. At the end of the plantation era of Jekyll Island, Newton Finney, suggested to Dubignon, his w rencontre, that they might acquire w rencontre island and then sell it to Northern businessmen as a winter resort. New York real estate developer and director of The Chemical Bank. As to w rencontre, the plasma of stallions and entire male w rencontre contains high levels of oestrogens, although mainly in the conjugated form. Il est domicilié à Rencontres célibataires morbihanoù il possède un ranch dans lequel il passe ses vacances.
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