Injection Of Oxytetracycline Research Articles

The Effect of Subcutaneous Injection of Oxytetracycline and Vitamins in Day-Old Broiler Chicks

Day-old broiler chicks were divided into two treatment groups; one received a single subcutaneous injection of oxytetracycline and vitamins; the second remained nonmedicated. Individual body weights were taken on days 7, 14, and 56 posttreatment, and a significant difference (P≤.05) was observed due to treatment at days 7 and 14. No significant differences were observed for overall mortality or body weight at day 56.

Distribution of penicillin G, dihydrostreptomycin, oxytetracycline, and chloramphenicol in serum and subcutaneous chamber fluid.

Penetration of penicillin G, dihydrostreptomycin, oxytetracycline, and chloramphenicol into interstitial fluid of calves was estimated using subcutaneously implanted, multiple perforated spherical polypropylene capsules as a model. Antibiotic concentrations were determined in simultaneously withdrawn serum and capsular fluid (CF) samples at intervals after single and multiple intramuscular injections of antibiotics at recommended dose schedules. Peak concentrations of penicillin G in CF were 57% of those in serum, and the drug was eliminated from CF at a slower rate than from serum. Dihydrostreptomycin diffused into CF to a limited degree and was eliminated from CF much more slowly than from serum leading to gradual drug accumulation in CF upon repeated dosing. Multiple injections of oxytetracycline resulted in CF drug levels comparable with those in serum. Concentrations of chloramphenicol in CF were generally similar to free (non-protein bound) serum drug levels. CF concentrations of penicillin G were within the range of the minimal inhibitory concentrations of the drug for pathogenic gram positive micro-organisms and CF levels of dihydrostreptomycin, oxytetracycline, and chloramphenicol were apparently sufficient to inhibit the majority of gram negative pathogens involved in bovine injections. Advantages and limitations of the tissue cage model are briefly discussed.

Tetracycline labeling of bone in vivo.

We have analyzed various aspects of tetracycline labeling technique for the measurement of bone apposition rate in vivo. Our efforts were restricted to those aspects that are frequently questioned when data obtained using this technique are interpreted as representing the rate of bone apposition. Rat bone was labeled in vivo by sequential injections of oxytetracycline at a dose range of 3 to 24 mg/kg body weight and at intervals ranging from 24 to 72 h. The bone apposition rate was calculated by measuring the distance from the first dose of label to the subsequent ones. As these distances are by far too small to be determined accurately by any available micrometer eyepiece, we have used a scanning microscope photometer which allows measurements on slow-forming sites that otherwise would have been considered nongrowing sites. Using these techniques, we have demonstrated that oxytetracycline has no effect on the bone apposition rate when used in the concentrations indicated. In addition, we found that at labeling intervals of 96 h or more, periods of osteoblastic inactivity are likely to be included in measurements at individual sites. The instantaneous apposition rate is thus underestimated at these long time intervals.

Blood Levels of Oxytetracycline After the Use of a Long-Acting Formulation to Eliminate the Carrier State of Bovine Anaplasmosis

The purpose of this paper is to present data on the blood plasma levels of oxytetracycline which resulted when cattle were injected intramuscularly (IM) once a week with a strengthened and improved formulation of oxytetracycline containing 200 mg/ml of base drug. One injection of this formulation has been reported to have an inhibitory effect on the parasitemia in acute anaplasmosis equivalent to three daily injections of oxytetracycline containing 50 mg/ml (2). Also, the former formulation has been recently reported to effect the elimination of the carrier state of bovine anaplasmosis when administered IM at seven-day intervals (3).
 The use of tetracycline drugs at relatively high dosage levels for varying periods of time has been an accepted procedure for eliminating A. marginale infection. Either prolonged feeding of chlortetracycline or daily injection of oxytetracycline have been used for this purpose in a number of earlier studies. The present study suggests that the use of a long-acting oxytetracycline will effectively eliminate the carrier state of sensitive strains of A. marginale. Also, the present study shows that in a limited ·number of cattle, detectable blood levels were present in 10 of 12 cattle seven days after one treatment with the long-acting formulation of oxytetracycline. It will be necessary to further evaluate the use of this treatment regimen to determine if similar results can be achieved under field conditions.

Carcass and Liver Composition Following Acute Oxytetracycline Treatment of ob/ob Mice

Fully mature (24-week old) C57BL/6J ob/ob mice and their lean littermates received daily oxytetracycline injections (50 or 100 mg/kg) during a 10 day period. The effects of the drug on the glucose, IRI, corticosterone levels, and on hepatic and body composition of ad libitum fed obese mice were compared with those of food-restricted and ad libitum fed lean and obese control animals. When compared with food-restricted obese mice, drug treatment led to substantial reductions of serum glucose, serum IRI, carcass fat, and hepatic lipid content, while it increased lean body mass and liver glycogen concentration. Similarly, oxytetracycline decreased body weight, and serum glucose in lean mice, but the drug had no substantial effect on circulating IRI levels or on the lipid content of carcass. A significant increase in hepatic lipid was observed in drug-treated lean mice. No effects of the drug on basal corticosterone levels were noted in either phenotype. These data support previous findings showing the effectiveness of oxytetracycline to reverse many of the metabolic abnormalities of ob/ob mice. In addition, the present results suggest that the drug acts by independently altering abnormal metabolism in many target organs, including pancreas, adipose tissue, liver, and muscle, rather than by merely reducing circulating insulin levels or by generally increasing insulin sensitivity.

Age dependent effects of oxytetracycline in ob/ob mice.

The effects of daily oxytetracycline injections on the metabolism and growth of prepubertal, 10 and 24-week old ob/ob and lean mice were examined. Drug treatment (100 mg/kg) between 17 and 28 days of age similarly reduced body weight gain and skeletal growth of both ob/ob and lean mice, but had little effect on obesity, serum glucose, or IRI levels. In older obese mice, 6 days of oxytetracycline led to substantial reductions of serum glucose, serum IRI, and obesity when compared with either ad libitum fed obese mice or food-restricted ob/ob mice serving as weight loss controls. In lean mice oxytetracycline also significantly reduced body weight and serum glucose, while no effects on obesity or IRI levels were noted. The present data show that oxytetracycline reduces the severity of many of the diabetic symptoms of ob/ob mice, but that only the ameliorative effects on obesity and hyperinsulinaemia appear to be specific to the ob/ob genotype.

A microfluorescent and scanning electron microscope study of the effects of acrylic reinforced and rapid palatal expansion appliances on the mid-palatal suture in Macaca mulatta

The use of acrylic-free and acrylic-reinforced appliances in cases of maxillary constriction has been reported extensively, but no controlled investigation has evaluated these two appliances by means of microfluorescence and the scanning electron microscope. In three groups of dentally matched Mncaca ntulatta female pairs, each received either an acrylic-reinforced or an acrylic-free appliance. A seventh animal served as a control. Weekly intravenous injections of oxytetracycline labeled new bone formation. In addition to the microfluorescent evaluation of the suture, the soft-tissue palate was critically dried, coated with gold and carbon, and examined under the scanning electron microscope. Preliminary results indicate that little difference is evident in the midpalatal suture between the acrylic-free and the acrylic-reinforced appliances. The scanning electron microscope indicated that acrylic-reinforced appliances are more likely to cause tissue irritation and sloughing.

A comparative microfluorescent study of the effects of acrylic-reinforced and acrylic-free rapid palatal expansion appliances on the alveolus and palatal shelves

Seven rhesus monkeys were used, with matched pairs having the same or different appliances. There was one control animal. Previous to and at regular intervals throughout treatment the monkeys were given intravenous injections of oxytetracycline to label new cellular activity in the bone. Sections of the maxillae were taken and analyzed by means of microfluorescence for changes in the bone and soft tissue. Evidence indicates that the two appliances are equally effective in widening the maxillary palates. Differences included both a wider maintained palatal vault with the acrylic-free appliances, and more softand hard-tissue necrosis with the acrylic-reinforced appliances. Both appliances tipped the teeth to the same degree in the early stages of activation, and the teeth became equally uprighted with either appliance. The retention and maintenance of the increased arch width were the same with both appliances, as also were the rate and degree of relapse. Both appliances proved to be very effective in achieving increased arch width, although the acrylic-free (Hyrax) appliance permitted healthier soft tissue and a wider vault maintenance.

An investigation of antibiotic and drug residues in fish.

The use of antibiotics and drugs in fish farming has prompted an investigation into the elimination of these residues from fish muscle. Young rainbow trout were given intraperitoneal injections of either chloramphenicol, framycetin, oxytetracycline or sulphadiazine/ trimethoprim and muscle tissue was examined by microbiological assay over a period of weeks for the presence of active residues. The effect of the method of administration of two of the drugs was also investigated and the results discussed.

Effect of oxytetracyclineand purified calcein (DCAF) on theapposition and mineralization of rat incisor dentin

Thirty male rats in groups of ten were given intraperitoneal injections of oxytetracycline and purified calcein (DCAF) every day for 10 d in order to determine whether these fluorescent hard tissue markers per se had any adverse effects on weight development and dentin apposition and mineralization. It was found that oxytetracycline and DCAF in doses of 15 mg/kg, which are the routine doses used by the author in hard tissue studies, do not seem to have any measurable influence on these parameters, while their ability to cause fluorescence is fully satisfying in dentin as well as in bone.

Environmental Impact of Lethal Yellowing Disease of Coconut Palms

Lethal Yellowing disease has been devastating Coconut, and presumably 14 other species of palms (including Palmyra and Date Palms), in mainland Florida since 1971. The urban environment has changed rapidly with the death of palm trees along streets, parks, and beaches. The disease is now present around the Caribbean Sea and presumably in West Africa.Widespread injections of oxytetracycline into both diseased and healthy palms are now being carried out in Florida in an effort to control the disease temporarily. The vector has not yet been identified. ‘Malayan Dwarf’ variety and the newly developed ‘Maypan’ hybrid are resistant to the disease and are being used to replace more susceptible varieties.The potential for environmental and economic disaster from the introduction of the disease to unaffected tropical countries, and the need for controlling its spread, are emphasized.

Effect of hypophysectomy on longitudinal bone growth in the rat.

The effect of hypophysectomy on the growth in length from the proximal growth plate of the tibia in female Sprague-Dawley rats was studied with the tetracycline method. The body weight was registered. The completeness of the hypophysectomy was determined microscopically on serial sections of the sella turcica. Hypophysectomy was found to have a retarding effect on longitudinal bone growth. In animals operated at 40 days of age the growth does not cease. The longitudinal growth decreases and reaches a low basal level about 10 days postoperatively. A single dose of 45 mg/kg cortisone acetate given at hypophysectomy has a growth retarding effect postoperatively. When hypophysectomy was performed at 30, 40, 50, or 60 days of age, young animals have a higher basal growth rate than older animals. The width of the fluorescent band, corresponding to a postoperative injection of oxytetracycline, is correlated to the growth rate and can be used as an index of the growth rate. The postoperative accumulated growth and the width of the fluorescent band indicate the functional efficacy of the hypophysectomy, and make it possible to separate animals with complete and incomplete hypophysectomy. Knowledge about the basal growth is important for the evaluation of the growth stimulating effect of different hormones.

The effect of roentgen irradiation on the formation of enamel and dentin in maxillary rat incisors

abstract – An investigation of roentgen‐ray induced enamel and dentin changes in the maxillary incisor in the rat was undertaken to assess the relative radiosensitivity of amelogenesis and dentinogenesis. Seventy Sprague‐Dawley rats received whole body irradiation with exposures between 500 and 950 rad. Five animals served as controls. During the experimental period all the animals were given an injection of oxytetracycline. The animals were killed 5–21 d after irradiation. Ground sagittal sections of the incisors were examined microradiographically and with fluorescence microscopy. The irradiation produced elongated external hypoplastic lesions in the enamel and niches in the dentin. The extent of the lesions varied with the radiation dose. The variation in the extent and appearance of the lesions was much greater in the dentin than in the enamel. Even the smallest dose regularly produced changes in the enamel but seldom in the dentin. Amelogenesis thus proved to be more radiosensitive than dentinogenesis.

Evidence on Possible Mycoplasma Etiology of Aster Yellows Disease II. Suppression of Aster Yellows in Insect Vectors

Chlortetracycline or chloramphenicol (but not kanamycin, penicillin, or erythromycin), when administered in hydroponic solution to diseased aster, reduced the availability of the aster yellows (AY) agent to nymphs of Macrosteles fascifrons (Stål). Insects exposed to healthy plants whose roots were immersed in chlortetracycline were able to acquire AY agent from diseased plants the day after removal from the antibiotic-treated plants, but the latent period of the ensuing disease in the insects was prolonged. Chlortetracycline or tylosin tartrate blocked AY infection in nymphs injected with a mixture of antibiotic and the AY agent, but polymyxin, neomycin, vancomycin, penicillin, carbomycin, or chloramphenicol did not. All tetracyclines tested, methacycline, oxytetracycline, and chlortetracycline, produced a dramatic reduction in the ability of infected vectors to transmit AY agent. Tylosin tartrate also reduced transmission when injected into AY-transmitting vectors, but carbomycin, spectinomycin, cycloserine, penicillin, erythromycin, or kanamycin had no such effect. During the first 10 days after injection of tylosin tartrate or oxytetracycline into transmitting vectors, ability of the insects to transmit AY decayed rapidly. Transmission by insects injected with buffer alone, after decreasing the first day after injection, gradually returned to its normal level in less than 1 week. By 2 to 3 weeks after injection with tylosin or oxytetracycline, ability to transmit AY was regained by vectors. The results suggest that tetracycline antibiotics and tylosin tartrate inhibit multiplication of AY agent in the insect. The spectrum of antibiotic activity in the insect is consistent with the hypothesis that AY and other plant yellows diseases are caused by mycoplasma-like organisms.

The influence of antibiotics on experimental moniliasis

The effects of the intraperitoneal administration of oxytetracycline and chlortetracycline on mice of strain CBA each inoculated by the same route with 6 million cells ofCandida albicans were assessed primarily on the basis of histological examination. An injection of oxytetracycline given at a dosage of 2.5 mg two hours after fungal inoculation, and repeated 24 hours later, resulted in the appearance of enhanced forms of systemic infection as indicated by early mortality. Enhancement of infection was referred to two forms:—1. Degenerative enhancement determined the deaths of some animals following the appearance of cloudy swelling in the cellular elements of the heart and kidneys, and was not related to the degree of fungal colonisation, which was frequently meagre or occasionally absent. 2. Colonial enhancement was regarded as involving a rapid colonisation of the tissues of the heart and kidneys by a pseudomycelial growth form of the fungus. In this type of infection, histological evidence of an impairment of leucocytic function in the host was obtained. Inoculated mice, previously treated with oxytetracycline or chlortetracycline (both at dosages of 2.5 mg) and variously treated 2 to 72 hours later with these antibiotics, gave no evidence of enhancement of infection. Both antibiotics, however, contributed to an increase in regional infection within the peritoneal cavity. Multiple regional infection was increased by 60% by the use of oxytetracycline, and by 50% by the use of chlortetracycline. The percentage of systemic disease reactions rose in inoculated animals receiving oxytetracycline: it fell significantly where chlortetracycline had been employed, denoting the existence of protection from systemic infection. Both enhancement of and protection from infection were viewed as manifestations of the modification of a basic, systemic mechanism of host defence.

Treatment of acute gonorrhoeal urethritis in the male with a single injection of oxytetracycline.

Treatment of acute gonorrhoeal urethritis in the male with a single injection of oxytetracycline.