[Biopharmaceutical and clinico-pharmacological research on the intramammary preparation Cephamasten]. / Biofarmatsevtichni i klinikofarmakologichni prouchvaniia na intramamarniia preparat tsefamasten.

An animal drug formula, Cephamasten, for intramammary application in the treatment of mastitis-affected cows, ewes, and goats in the lactation period was worked out on the base of microbiologic, technologic, biopharmaceutic, and clinico-pharmacologic studies. Its active ingredient was the Pharmachim cephalexin-monohydrate. The consistence of Cephamasten has proved suitable for intracisternal introduction. It is tolerated well within the udder of cows, and it rapidly releases the antibiotic incorporated in it. The milk of the treated quarters has proved free from cephalexin after the 72nd hour of the last infusion. Cephamasten has shown high effectiveness in the treatment both of the preclinical and of the acute clinical mastitis. In the first case best results were obtained with the twofold treatment at a 24-hour interval, and in the second case--with the sixfold treatment at 12-hour intervals (intracisternal introduction of the preparation). In the case of generalized mastitis, in dependence on the severity of the process Cephamasten is to be applied at 4-6-12 intervals along with frequent milking and the parenteral application of other agents.

[Toxicological research on a protein-vitamin B12 concentrate in broiler chicks]. / Toksikologichni prouchvaniia vurkhu beltuchno-vitaminen kontsentrat-B12 pri pileta broileri.

Studied were the acute and the subchronic toxicity, and the total tolerance of birds with regard to the Bulgarian protein-vitamin concentrate B12 (PVC-B12) with manifested activity of 230 mg per kilogram. With single introduction into the crop at rates of up to 20 g/kg PVC-B12 had no unfavourable effect on the health of birds. The same applied to its manifold use over a period of 10 days when given with the feed in amounts that exceeded ten and twenty times the recommended prophylactic and stimulating doses. As feed supplement at rates of 4 and 12 g/100 kg in the course of 56 days the preparation did not induce changes in the appetite, behaviour, general condition, clinical and biochemical composition of the blood, and structural organization and development of the viscera.

[Research on Pharmachim's ronidazole for its antifertility, embryotoxic and teratogenic action]. / Prouchvaniia vurkhu ronidazol "Farmakhim" za antifertilitetno, embriotoksichno i teratogenno deistvie.

Albino rats were used to study some remote side effects (total reproduction, embryotoxicity, and teratogenic action) of the Bulgaria Ronidazol-Pharmachim preparation, analogous to the one produced by the firm MS & D--USA (Ridzol 10 per cent water-soluble powder) used in veterinary practice as a prophylactic and therapeutic agent in the case of swine dysentery and turkey blackhead. It was found that at oral application of the amounts suggested as therapeutic means Ronidazol-Pharmachim did not show antifertility action. Orally (in the form of suspension), given over the entire period of pregnancy at rates of 20 mg per kg body mass (exceeding more than six times the recommended maximum of therapeutic doses) it did not produce embryotoxic and teratogenic effects. Certain hazards existed, however, of embryotoxicity (but not of teratogenic action) when used in doses that were twenty times higher.

[Trials using drugs in diseases of the silkworm (Bombyx mori L.)]. / Opiti za prilozhenie na lekarstveni sredstva pri bolestite po koprinenata buba (Bombyx mori L.).

Studied was the pharmacokinetic of chloramphenicol, tylosine, ampicillin, and penicillin in silkworm moths. The antibiotics were applied only once in the form of water solutions in concentrations of 0.062 to 1 per cent for chloramphenicol, 50 to 1500 IU/cm3 for tylosine, 0.03 to 0.5 per cent for ampicillin, and 300 to 2500 IU/cm3 for benzilpenicillin at the rate of 25 cm3/cm2 of a mulberry tree leaf. It was found that chloramphenicol in conc. 0.25 to 0.5 per cent was absorbed in the alimentary canal of the silkworm and was found in the haemolymph in bacteriostatic levels up to the 96th hour following treatment. Tylosine was also absorbed, and in concentrations of 500 to 1500 IU/cm3 was shown to maintain bacteriostatic levels in the haemolymph of the moths for a period of 24-32 hours. Ampicillin and penicillin were absorbed to a slight extent, and were eliminated from the haemolymph up to the eighth hour. It is suggested to use chloramphenicol and tylosine in the concentrations referred to for the control of the spontaneous nuclear polyhedria and flasheria in silkworm moths.

[Toxicological studies of a combination of technical tylosin phosphate with bentonite (farmazin TB)]. / Toksikologichni prouchvaniia vurkhu komibnatsiia na tekhnicheski tilozinov fosfat s bentonit (farmazin TB).

Studied were both the acute and subchronic toxicity of technical tylosine phosphate (TP), produced at the Research Chemical and Pharmaceutical Institute, Sofia, used in combination with bentonite, known as Pharmasine TB. Pharmasine TB was practically untoxic for albino mice and birds at oral application. Neither toxic nor lethal effects were observed after giving it once, twice, and three times at a 2-hour interval at rates of 5 and 10 g per kg body mass. Calves and pigs also showed very good tolerance for the preparation at oral application. At prolonged application via the feed (30 days) in amounts of 0.5, 1.5, and 2.5 per cent (equal to 100, resp., 300 and 500 ppm with regard to tylosine in active matter) Pharmasine TB was shown to stimulate the weight gain on the basis of the better utilization of feed, having no unfavourable effect on the appetite, behaviour, clinical and biochemical composition of blood, and the morphologic structure of the viscera in pigs. Used in the same way with birds at the rates of 3, 5, and 10 per cent (equal to 450, resp., 750 and 1500 ppm with regard to tylosine in active matter) for a time period of 60 days the preparation did not lead to deviations in terms of the most clinical and morphological indices, however, it inhibited the weight gain by 3.2 to 8.1 per cent. According to the authors, this was due incomplete biologic value of the medicated feeds and their improper utilization because of the introduction of rather greater amounts of bentonite with Pharmasine TB.

[Intramammary drug forms of neotil in treating mastitis during lactation]. / Prouchvaniia vurkhu intramamarnata lekarstvena forma "neotil" za lekuvane na mastiti po vreme na laktatsiia.

Technological, biopharmaceutical, and clinico-pharmacological studies were carried out on the varying composition of drug formulas that included a tylosin base and neomycin sulfate, intended for the treatment of mastitis-affected cows during the lactation period. A base was developed of suitable viscosity and physico-chemical properties, that rapidly released the active ingredients included in it and made them penetrate in depth in the udder glandular tissue. Both the base and the drug formula Neotil were shown to be well tolerated. Following the single intracisternal infusion tylosin was excreted with the milk up to fifth milking (the 60th hour), and neomycin--up to the 4th milking (the 48th hour). When applied therapeutically in the case of clinical and subclinical mastitis Neotil led to the clinical and bacteriological recovery of 92.5 per cent of the affected quarters. Developed was a microbiological method for the analysis of the active ingredients contained in the drug formula and the milk secretion.

[Toxicity of "Farmakhim" tetramisole in laboratory and farm animals]. / Prouchvaniia vurkhu toksichnostta na tetramizol "Farmakhim" pri laboratorni i selskostopanski zhivotni.

Tetramisole produced by ICI, England, and Tetramisole Pharmachim, Bulgaria, were comparatively studied in terms of their acute and subchronic toxicity, and the local and general tolerance and antinematode activity. No differences were found in their acute toxicity (LD50) for albino mice at oral, subcutaneous, and venous application, the index of resorption being 6.3. The same was true so far as the tolerance in calves, sheep, goats, and pigs was concerned. Orally at the rate of 45 mg/kg in sheep and over 30/kg with calves (3, resp., 2 times as high as the therapeutic dose) tetramisole produced nervous and locomotor excitement, tremor, salivation, higher respiration and pulse rate, frequent urination and defecation. Following the tenfold oral administration at intervals, of 3 days at rates of 15 and 45 mg/kg tetramisole Pharmachim did not affect unfavourably the appetite, behaviour, general status, and the clinical and biochemical composition of the blood as well as the structural pattern of the viscera in sheep. Tetramisole Pharmachim was shown to be well tolerated with regard to the conjunctivae at concentrations of up to 5 per cent, the subcutaneous tissues and muscles at conc. of up to 3 per cent, and mucous membranes of the stomach and intestines at conc. of up to 10 per cent.

[Treatment of bovine mastitis during the dry period and development of intramammary drug formulations]. / Lekuvane na mastitite po kravite prez sukhostoiniia period i problemi pri suzdavaneto na intramamarni lekarstveni formi.

Studied were the factors that govern the pharmacokinetics of the intracysternal introduction of therapeutic means into the dry udder (type of drug base, physical and chemical properties of the drugs themselves and the physiologic and functional status of the gland). It is stated that the development of intramammary drug formulas for cows in a dry period is a difficult and complex activity as it is associated with the requirement to overcome two main conditions that could hardly be combined from the standpoint of biopharmacy and pharmacology. These consist in that the need of high concentrations to produce a therapeutic effect is connected with the presence of active ingredients that can be readily released from the base, while the need of producing also of a prophylactic effect imposes the persistence of these concentrations in the glandular secretion, and this means that the active matter should be slowly released. There is no chemotherapeutic agent by now that could properly satisfy all these requirements in order to prepare intramammary drug formulations for dry cows. It is believed, therefore, that at present the need for such therapeutic means can be met through the modulation of the medicinal bases and the physical and chemical properties of the drugs themselves which are offered by the pharmaceutic industry.

[Pharmacological studies of Bulgarian gonadotropin preparations]. / Niakoi farmakologichni prouchvaniia vurkhu bulgarski gonadotropni preparati.

Experiments were carried out to prove the influence of SJK gonadotropic preparations (native and lyophilized), gravohormone and luteosiman, on the functional state of the central, the cardio-vascular and the respiratory systems, as well as that of the smooth musculature. It was proved that in doses under 20 MUI/kg t these preparations have no unfavorable effect upon the function of the cardio-vascular system (experiments were carried out on frog's hearts eliminated, on blood vessels of eliminated rabbit's ears and the hind limbs of frogs, on the blood pressure of cats and hens), upon the breathing (experiments on cats), the central nervous system and the muscular tonus (experiments on mice). In high dose SJK decreases blood pressure by slightly increasing in that direction the influence of histamine and acetylcholine. Breathing becomes uneven, stronger and accelerated. The muscular tonus is characterized by depression and decrease. A tonic effect was observed with the uterus, as well as increased contractions of the latter. The gravohormone taken in high doses provoked a decrease in blood pressure, an abatement and a depression of the tonus and motility of the eliminated uterus without any substantial changes of the rhythm and frequency of respiratory movements. In low and high doses (0,2, 20 and 60, 160 UI/kg t) it decreased the blood pressure of the narcotized hens, strengthened and increased the tonus of the motor activity of the uterus, which was probably due to residues of oxytocin.

[Clinical and pharmacological studies of technical tylosin phosphate from Pharmachem in poultry diseases]. / Kliniko-farmakologichni prouchvaniia na tekhnicheskiia tilozinov fosfat "Farmakhim" pri niakoi zaboliavaniia po ptitsite.

Investigations on the healing anbd prophylactic effectiveness of the technical tylosine phosphate "Pharmachim" with 50 IU/mg activity (pharmazin T-50) in some bird diseases were carried out. It was established that a dose of 20 g/kg fodder pharmazin T-50 applied 2 days pre- and 3 days post chicken Mycoplasma gallisepticum infection protects the chickens completely from respiratory mycoplasmosis. In order to attain a sure healing and prophylactic effect in hen spirohetosis control 10 g/kg fodder applied 2 days or on the 24th to 48th day after Borrelia anserina invasion are completely sufficient. It must be noted, moreover, that pharmazin T-50 application has not a negative effect on the build up of post-vaccinal immunity following the same illness. The good results obtained by pharmazin T-50 allow it to replace successfully the remaining medicinal preparations (some of which much more expensive) applied in the control of spirohetosis and respiratory mycoplasmosis of birds.

[Toxicological studies of Bulgarian activated bentonite]. / Toksikologichni prouchvaniia vurkhu bulgarski aktiviran bentonit.

We studied the endurance of calves, lambs and pigs as well as the acute, subchronic and chronic toxicity for chickens with regard to bentonite of local origin, extra activated in a physico-chemical way. It was proved that the medicine was rather endurable with calves, lambs and pigs without causing intoxication or death after a single internal introduction in doses respectively 4138, 4130 and 1860 mg/kg t. LD0 of the activated bentonite for the chickens in the case of intra-crop application was over 18000 mg/kg t. During a 33-day extra addition to the fodder of chickens in quantities of 2 and 6% and during a 90-day introduction into concentrations 1, 3 and 5% the activated bentonite and not provoke any changes in the behaviour, overall state and in the clinical biochemical and electrolytic composition (Ca, P, K, Na) of the blood, but it caused suppression of growth ranging from 6 to 27% and brought about a higher expenditure of food for a single growth unit ranging from 4.7 to 12.1%. This was also observed when it was added to the morning ration of pigs in doses 1 and 5% (6 and 30 d/pig) without any influence over the health state of the pigs, but it slowed down growth ranging from 17.2 to 21.3% and a lower utilization of the fodder taken by 19 to 26%.

[Pharmacokinetics of a new antibiotic preparation, novoolean]. / Farmakokinetika na noviia antibiotichen preparat novoolean.

We studied the resorption, the distribution, the duration of retention, as well as the routes of elimination by the organism of the complex antibiotic medicine (novobiocin salt of the oleandomycin). It was proved that after a single muscular injection of doses 20 and 50 mg/kg t the medicine, unlike its constituting components, possesses a retained action and keeps up bacteriostatic concentrations of blood in sheep, rabbits and chickens for a period of 12, respectively 24 hours. No substantial differences were observed between the blood levels created of the different species after the use of equal doses. No resorption was observed (or practically an insignificant one) in the digestive tract of rabbits. After its resorption from the place of its application the 'novoolean' penetrates into all organs studied, tissues and liquids of the organisms of guinea pigs, except for the brain. The longest period of retention is that in the lungs and in the kidneys. It is eliminated by the organism mainly through the urine and the bile secretion, and in the case of the lactating mammals-through the milk. The organism of the treated animals is practically free from 'novoolean' after the fourth day and as to the milk--after the second day of the last intramuscular injection.

[Acute and subchronic monensin toxicity for lambs]. / Ostra i subkhronichna toksichnost na monenzina za agneta.

The acute and subchronic toxicity of monenzine (preparation Elancoban -- 100 of Elanco Co., USA) to male lambs for fattening aged 3-4 months and weighing 16-28.5 kg was studied. It was established that the single per oral dose of 5 mg/kg weight of the natrium monoenzine salt causes a temporary lack of appetitie but no changes in the behavior and the general state of the animals. The use of a 10 and 30 mg/kg weight dose of the preparation led to death of the lambs on the 72nd-120th hour. The toxicity was clinically manifested by anurexia, arumination, ataxia, paresis, and paralysis of the limbs, tachicardia, taxipnea, hypothermia and showed down and weakened rumen movements. Erosive rumitis and abomasis, catharrhalhemorrhagis duodenitis, hemorrhages on the epicardis, hyperremia and parenchymal organ oedema, 3-4 times increased gall-bladder with numerous nodes having a sunken center on its walls were observed pathologo-anatomically, while microscopically blood vessel disturbances (hyperremia, hemorrhages and oedema) of the lungs, heart, spleen, endocrinal glands (thyroid, adrenal and hypophysis), the brain, and the leptomeninges, liver distrophy, distrophic nephrosis and necrotic holecystitis were obvious. Following a long term (30 days) application to the fodder in 10 and 50 g/t doses, monenzine-natrium does not have a negative effect on the behaviour, general condition, clinical and biochemical blood composition and the structural build up of the inner organs, but in the first 5-10 days of the treatment it causes loss of appetite. Additional specific investigations are needed to elucidate the effect of the preparation on body gain.

[Toxicological studies of the technical phosphate of Pharmachem tylosin]. / Toksikologichni prouchvaniia vurkhu tekhnicheskiia tilozinov fosfat "Farmakhim".

Studies on the acute, subchronic and chronic toxicity of technical tylosine phosphate (TTP) with 50 UI/mg activity, produced by Pharmachim were carried out. It was established that TTP does not cause lethality in white rats following application of 20, in white mice--of 40, in chickens--of 30 and in pigs--of 2 g/kg body weight. Long term application to the rations--of chickens for 40 days, in doses of 20, 40 and 60 g/kg fodder (=1.3 and 5 ED100) and of pigs for 32 days in doses of 2.6 and 10 g/kg fodder (=1.3 and 5 ED100) stimulates gain in weight of both species by 2-11.5% and improves the utilization of nutrition by 4.5-12.5% without any unfavourable effect on the clinical-biochemical composition of the blood and the structure and development of inner organs.

[Kinetic studies of the technical phosphate of Pharmachem tylosin in chickens and pigs]. / Prouchvaniia vurkhu kinetikata na tekhnicheskiia tilozinov fosfat "Farmakhim" pri pileta i praseta.

Studies on the pharmaco-kinetics of the technical tylosine phosphate (TTP) with an activity of 50 UI/mg were carried out using chickens and pigs. It was established that the tylosine phosphate contained in TTP is resorbed in the alimentary canal of the chickens and produces the needed bacteriological concentrations in the blood both following single intraingluvial application (in doses of 1 and 2 g/kg b.w.) and after application via fodder (in doses of 10 and 20 g/kg b.w.). Absorption of the preparation by the digestive tract of pigs following compulsory application is satisfactory, but it is very slight and uneven in case of application through the food ration. Therefore, the use of TTP in this way should be limited in swine only and exclusively for therapy or prophylaxis of intestinal infections (dysentery, necrotic enteritis, etc). Following resorption TTP penetrates to a varying extent in the individual organs, tissues and fluids of chicken and pig organisms and remains there for a long period of time. It is eliminated mainly through the gall bladder secretion and by the urine, as well as by the eggs (of layers). In order not to allow residual quantities of the antibiotic in the products obtained from treated mammals and birds TTP application must cease 4--5 days before decapitation. The use of preparation for hens of commodity farms is not appropriate.

[Several pharmacokinetic studies on "Farmakhim" tylosin phosphate]. / Niakoi farmakokinetichni prouchvaniia vurkhu tilozinoviia fosfat "Farmakhim".

Studies were carried out on the resorption in the digestive tract the binding with the tissue elements, the dissemination within the body, and the residual amounts of tylosine "Pharmachim" phosphate and its pelleted drug formulation tylosine-200. It was found that tylosine-200 was well resorbed by the intestinal mucosa of pigs and birds, and was weakly and variably utilized by calves. The blood concentrations of tylosine-200 in pigs and birds in the first hours following treatment surpassed by 1 to 5 times those resulting from the administering of the analogous therapeutic formula Tylan AF 99 of the Elanco Firm. The tylosine phosphate was found to combine reversely with the tissue in birds and pigs. The quantitative indices of this process were used to specify the actual content of the antibiotic in the body. Experiments with birds and pigs revealed that the tylosine phosphate released from tylosine 220 pellets invaded to a virious extent organs, tissues, and fluids and passed through seroses, and the blood-brain and blood-ocular barriers. It was excreted in substantial amounts with the urine and the bile. It was established that on the 5th day after the administration of the drug was discontinued the body of mammals and birds was practically free from the preparation. No differences in the distribution within the body and the retention were found between tylosine-200 and Tylan AF 99.

[Control of mycoplasmosis via poultry eggs and sperm by using tylosin]. / Izsledvaniia za ogranichavane na mikoplazmozata chrez iaitsata i spermata na ptitsite s pomoshtta na tilozin.

A review is made on the existing references concerning the utilization of tilosin and some other antibiotics for limiting the distribution of or complitely eliminating mycoplasmosis in poultry and turkeys. Opportunities are discussed for preventing the emission of mycoplasmae with the eggs and spermal liquid of the diseased birds (treatment of the egg layer or of the sperm), as well as methods for elimination of the infection on the eggs (pre-incubation heating, dipping in antibiotic solutions or injection of various antibiotics). Most effective proved to be the methods of tilosin injection in the air camera of the eggs (1--3 mg/egg between the 7th and the 11th day from the beginning of incubation) and pre-incubation dipping of the eggs in tilosin solutions of 1000--3000 ppm concentrations. Cheaper and more suitable for practical use is the first method. Precise recommendations are given for obtaining PPLO-free bird flocks.

[Pharmacological and toxicological studies of novoolean]. / Niakoi farmakologichni i toksikologichni prouchvaniia na novooleana.

A toxicologic study and some pharmacologic investigations were carried out with the novobiocin salt of oleandomycin, formulated as novoolean. The LD50 of the of the preparation for i/m application to mice proved equal to 1500, and to rats--1800 mg per kg of body weight. For oral introduction the average lethal dose for mice amounts to 3250 mg/kg. At such route of application on deaths were observed in rats after the administration of 5 000 mg/kg. A 30-day treatment via i/m application to rats of 180 mg/kg (which is equal to one tenth part of LD50) did not lead to changes in the growth, blood picture, and a number of clinical and biochemical indices of the blood and urine; there were no changes in the development and the structure of the viscera as well as the reproductive capacity of the test animals. Electron-microscope studies with rats treated in the same period with 360 mg/kg (one fifth of the LD50 value) revealed certain injuries of the liver kidneys. With cats the venous infusion of the preparation at rates of up to 15 mg/kg showed no changes in the blood pressure and the rhythm and pulse rate, and the addition of novoolean to the nutrient solution in concentrations of up to 100 mg/cu. cm did not influence the tonus and the motor function of isolated (after Magnus) sectioned portions of the small intestine of rabbits and guinea pigs.

[Physicochemical studies of Pharmachem's tylosin]. / Niakoi fiziko-khimichni prouchvaniia vurkhu tilozin "Farmakhim".

Studied is the effect of high temperature, light, moisture, the type of the solvent and the reaction in the medium on the chemical stability and biological activity of the tylosine base, tylosine tartarate and tylosine phosphate, produced by the "PHARMACHIM" State Economic Corporation. The evaluation of the effect is carried out by using the spectrophotometric (in the UV-region) and microbiological methods (diffusion in agar with Sarcina lutea A. T. C. C. 7341 as a test microorganism). It is found that tylosine is stable thermally both as substance and as solution, yet it loses a large part of its activity when the solutions are exposed to ultraviolet or direct sun light. This calls the solutions of the antibiotics in the course of their preparation, storage and application to be protected from the direct effect of light and that they should be packed in light-proof material. Depending on the air moisture (72--98 per cent), the tylosine base absorbs water from 4 to 11 per cent, the tartarate--from 9 to 37.5 per cent, the phosphate--from 8 to 28.5 per cent, the tylosine tartarate (water-soluble form)--from 7 to 32 per cent, and the tylosine phosphate (granules)--from 12 to 39 per cent of their weights. This requires their storage to be limited to dry, airy premises or they should be hermetically packed. Water, ethanol, methanol, phosphate buffers with pH 6--10.0, dimethylformamide and dimethylsulphoxide do not affect the activity of tylosine, but the last two solvents inhibit the diffusion of the antibiotic in agar and are unsuitable for biological tests. The tylosine base, manufactured by the "Elanco" Company, manifests similar properties in relation to thermal stability, light sensitivity, hygroscopicity and diffusions in agar.

[Toxicity studies of Pharmachem's tylosin tartrate for broilers and turkeys]. / Prouchvane vurkhu toksichnostta na tilozinoviia tartarat "Farmakhim" za pileta broileri i puiki.

Studied were the acute, subchronic, and chronic toxicity of the Pharmachim tylosin tartrate as well as the tolerance of chicken broilers and turkeys. The mean lethal dose of the antibiotic at subcutaneous application to 28-32 day-old broilers was 620 mg/kg; the oral dose was 1500 mg/kg. In the case of 42-45-day-old broilers these values were 740 and 5400 mg/kg. The LD50 at i/v infusion for 75-77-day-old ones was 48 mg/kg. Beside the age and route of introduction toxicity was found to depend on the initial biologic activity of tylosin tartrate. The subcutaneous injection of tylosin tartrate at the rate of 30 mg/kg for 20 days did not lead to changes in the appetite, behaviour, growth, and structure of viscera. A 42-day treatment at the same rate, however, resulted in slightly manifested and fully reversible dystrophic changes in the liver and kidneys. Higher doses (90 and 150 mg/kg) led to transient depression, stunting of growth, and a rise of the urea level and the activity of blood transaminases as well as to moderate destructive changes in the liver and kidneys. The stimulation of growth and the improvement of feed conversion (without deviations in the clinical and biochemical indices of the blood and the structure and development of the viscera in broilers) were recorded after the application of a water-soluble formula of tylosin tartrate for a period of 98 days offered via the drinking water in amounts equal to or exceeding 2 to 4 times the ED50. Turkeys' tolerance for the preparation was evaluated as very good so far as single i/m injective applications were concerned in doses exceeding 3, 5, and 10 times the average effective rates, no differences in this respect being noted with the comparative use of tylosin tartrate produced by the Elanco firm.