Patent Application
20160095865
The invention belongs to the field of livestock and poultry breeding and specifically relates to application of an enrofloxacin salt in preparation of an oral preparation for pigs.
Enrofloxacin is the first special quinolone type antibiotic species for animals, has a broad-spectrum bactericidal effect and is effective to bacteria in a stationary phase and a growth phase. The enrofloxacin has a good antibacterial effect on a variety of gram-negative bacilli and cocci, and the MIC against the overwhelming majority of strains of sensitive bacteria is lower than 1 ug/ml. The enrofloxacin is widely applied in the aspect of treatment of animal bacterial infections. At present, the forms of the enrofloxacin in commercial products include enrofloxacin base, enrofloxacin sodium and enrofloxacin hydrochloride. It is found in the production practices that the enrofloxacin salt in the three forms has very poor palatability to the pigs and can not be orally administered or administered by mixing, possibly due to the special physiological basis of the pigs. Thus, the enrofloxacin has long been only limited to injections in the application in pig-raising industry.
An object of the invention is providing application of an enrofloxacin salt in preparation of an oral preparation for pigs.
In the testing process, the inventors found that salts formed by enrofloxacin and part of monovalent (Ag+ etc.) or divalent (Zn2+ or Cu3+ etc.) metal ions could significantly improve the palatability of the enrofloxacin, and could be developed into a preparation administered via the digestive tract, for pig-raising production without affecting the normal feed intake of the pigs. In addition, pharmacokinetics and artificial infection test prove that the salt formed by the enrofloxacin and the metal ions does not affect bioavailability.
Thus, the invention provides application of an enrofloxacin salt in preparation of an oral preparation for pigs, wherein the enrofloxacin salt is at least one of salts formed by enrofloxacin and metal ions, and the metal ions are zinc, copper, calcium, magnesium, iron, cobalt, manganese, chromium, silver or nickel.
The enrofloxacin salt is further preferably enrofloxacin zinc, enrofloxacin copper or enrofloxacin silver.
Preferably, the enrofloxacin zinc is a complex formed by the enrofloxacin and zinc ions according to the molar ratio of 2:1, the enrofloxacin copper is a complex formed by the enrofloxacin and copper ions respectively according to the molar ratio of 2:1, and the enrofloxacin silver is a salt formed by the enrofloxacin and silver ions according to the molar ratio of 1:1.
The oral preparation includes the oral preparation which is orally given or administered via feed or drinking water, and including, e.g., powder, granules, suspensions, emulsions, tablets and pills, etc.
The invention also provides an oral preparation for pigs containing an enrofloxacin salt as an active ingredient, wherein the enrofloxacin salt is at least one of salts formed by enrofloxacin and metal ions, and the metal ions are zinc, copper, calcium, magnesium, iron, cobalt, manganese, chromium, silver or nickel.
The enrofloxacin salt is further preferably enrofloxacin zinc, enrofloxacin copper or enrofloxacin silver.
Preferably, the enrofloxacin zinc is a complex formed by the enrofloxacin and zinc ions according to the molar ratio of 2:1, the enrofloxacin copper is a complex formed by the enrofloxacin and copper ions respectively according to the molar ratio of 2:1, and the enrofloxacin silver is a salt formed by the enrofloxacin and silver ions according to the molar ratio of 1:1.
The oral preparation includes the oral preparation which is orally given or administered via feed or drinking water, and including, e.g., powder, granules, suspensions, emulsions, tablets and pills, etc.
The enrofloxacin salt formed by the enrofloxacin and the metal ions in the invention can significantly improve the palatability of the enrofloxacin to pigs. Furthermore, pharmacokinetics study and artificial infection test prove that the enrofloxacin salt formed by the enrofloxacin and the metal ions does not affect bioavailability. As a result, the enrofloxacin salt can be developed into an oral preparation administrated via the digestive tract, for pig-raising without affecting normal feed intake of the pigs.
The following embodiments are used for further describing the invention rather than limiting the invention.
The general formula for the preparation of the enrofloxacin zinc is as follows. 100.0 g of enrofloxacin sodium was dissolved in water and the volume was set to 1000 mL to obtain an enrofloxacin sodium solution. 40.0 g of zinc sulfate heptahydrate was dissolved in water and the volume was set to 1000 ml to obtain a zinc sulfate solution. The zinc sulfate solution was slowly added dropwise into the enrofloxacin sodium solution at room-temperature under stirring for reaction, and the stirring for reaction was continuously performed for 1 h after the end of adding to complete reaction. A suction filtration was performed on the reaction solution, a suction filtration and washing were performed on the filter cake with 3000 ml of water, and the filtration residues were dried at 80° C. till constant weight so as to obtain the enrofloxacin zinc. 99.30 g of sample was produced, and the reaction yield was 96.9%.
2C19H21FN3O3Na+ZnSO4.7H2O═(C19H21FN3O3)2Zn+Na2SO4+7H2O
The general formula for the preparation of the enrofloxacin copper is as follows. 100.0 g of enrofloxacin sodium was dissolved in water and the volume was set to 1000 mL to obtain an enrofloxacin sodium solution. 40.0 g of copper sulfate pentahydrate was dissolved in water and the volume was set to 1000 ml to obtain a copper sulfate solution. The copper sulfate solution was slowly added dropwise into the enrofloxacin sodium solution at room-temperature under stirring for reaction, and the stirring for reaction was continuously performed for 1 h after the end of adding to complete reaction. A suction filtration was performed on the reaction solution, a suction filtration and washing were performed on the filter cake with 3000 ml of water, and the filtration residues were dried at 80° C. till constant weight so as to obtain the enrofloxacin copper. 98.2 g of sample was produced, and the reaction yield was 95.93%.
2C19H21FN3O3Na+CuSO4.5H2O═(C19H21FN3O3)2Cu+Na2SO4+5H2O
The general formula for the preparation of the enrofloxacin silver is as follows. 100.0 g of enrofloxacin sodium was dissolved in water and the volume was set to 1000 mL to obtain an enrofloxacin sodium solution. 50.0 g of silver nitrate was dissolved in water and the volume was set to 1000 ml to obtain a silver nitrate solution. The silver nitrate solution was slowly added dropwise into the enrofloxacin sodium solution at room-temperature under stirring for reaction, and the stirring for reaction was continuously performed for 1 h after the end of adding to complete reaction. A suction filtration was performed on the reaction solution, a suction filtration and washing were performed on the filter cake with 3000 ml of water, and filtration residues were dried at 80° C. till constant weight so as to obtain the enrofloxacin silver. 126.6 g of sample was produced, and the reaction yield was 96.89%.
C19H21FN3O3Na+AgNO3═C19H21FN3O3Ag+NaNO3
100 105-day-old healthy duroc-landrace-yorkshire hybrid pigs with similar body weights were divided into 10 test groups as shown in Table 1, and each group comprised 10 pigs. Enrofloxacin base, enrofloxacin sodium and enrofloxacin hydrochloride were respectively added in feed in each group. All the test pigs were synchronously fasted for 12 h before testing. The test pigs in each group were respectively subjected to free feed intake of feed containing enrofloxacin in different forms after the 12 h fast. Observation was performed for 30-60 minutes till the test pigs did not take feed any more. Feed consumption of different test groups was subjected to statistics and the influence of different forms of the enrofloxacin added in the feed on the feed intake of the pigs was evaluated. The pure feed which was not added with the enrofloxacin or the salt thereof was taken as control.
As the enrofloxacin base, the enrofloxacin sodium or the enrofloxacin hydrochloride was added in the feed, the feed intake of each test pig was significantly reduced. Comparing with a blank control group, the feed intake in each of the test groups added with 5 ppm of enrofloxacin base, enrofloxacin sodium or enrofloxacin hydrochloride respectively was reduced by 47.2%, 50.8% and 49.5% respectively, and the test pigs in the group added with 100 ppm of the enrofloxacin in different forms showed apastia (See table 2 for the results).
150 110-day-old healthy duroc-landrace-yorkshire hybrid pigs with similar body weights were divided into 5 test groups as shown in Table 3, and each group performed three repeats. The feed in each group was added with different doses of the enrofloxacin or the salt thereof. All the test pigs were synchronously fasted for 12 h before testing. The test pigs in each group were respectively subjected to free feed intake of feed containing enrofloxacin or the salt thereof after the 12 h fast. Observation was performed for 30-60 minutes till the test pigs did not take feed any more. Feed consumption of different test groups was subjected to statistics and the influence of different forms of the enrofloxacin on the palatability of pig feed was evaluated. The pure feed which was not added with the enrofloxacin or the salt thereof was taken as control.
As the enrofloxacin or the salt was added into the feed, enrofloxacin sodium basically completely inhibited the feed intake behavior of pigs, while salts formed by enrofloxacin and zinc, copper and silver had no significant influence on the feed intake of the test pigs (See table 4 for the results).
120 110-day-old healthy duroc-landrace-yorkshire hybrid pigs with similar body weights were divided into 4 test groups as shown in Table 5, each group performed three repeats, and each repeat was performed on 10 pigs. The feed in each group was added with different doses of the enrofloxacin zinc respectively. All the test pigs were synchronously fasted for 12 h before testing. The test pigs in each group were respectively subjected to free feed intake of feed containing enrofloxacin zinc in different forms after the 12 h fast. Observation was performed for 30-60 minutes till the test pigs did not take feed any more. Feed consumption of different test groups was subjected to statistics and the influence of different doses of the enrofloxacin zinc added into the feed on palatability of pig feed was evaluated. The pure feed which was not added with the enrofloxacin or the salt thereof was taken as control.
As feed was added with different doses of enrofloxacin zinc, the feed intake of the test pigs had no significant difference from that of a control group (the pure feed which was not added with enrofloxacin or the salt thereof) (See table 6 for the results).
120 115-day-old healthy duroc-landrace-yorkshire hybrid pigs with similar body weights were divided into 4 test groups as shown in Table 7, each group performed three repeats, and each repeat was performed on 10 pigs. The feed in each group was added with different doses of the enrofloxacin copper respectively. All the test pigs were synchronously fasted for 12 h before testing. The test pigs in each group were respectively subjected to free feed intake of feed containing enrofloxacin copper in different forms after the 12 h fast. Observation was performed for 30-60 minutes till the test pigs did not take feed any more. Feed consumption of different test groups was subjected to statistics and the influence of different doses of the enrofloxacin copper added into the feed on palatability of pig feed was evaluated. The pure feed which was not added with the enrofloxacin or the salt thereof was taken as control.
As feed was added with different doses of enrofloxacin copper, the feed intake of the test pigs had no significant difference from that of a control group (See table 8 for the results).
120 120-day-old healthy duroc-landrace-yorkshire hybrid pigs with similar body weights were divided into 4 test groups as shown in Table 9, each group performed three repeats, and each repeat was performed on 10 pigs. The feed in each group was added with different doses of the enrofloxacin silver respectively. All the test pigs were synchronously fasted for 12 h before testing. The test pigs in each group were respectively subjected to free feed intake of feed containing enrofloxacin silver in different forms after the 12 h fast, observation was performed for 30-60 minutes till the test pigs did not take feed any more. Feed consumption of different test groups was subjected to statistics and the influence of different doses of the enrofloxacin silver added into the feed on palatability of pig feed was evaluated. The pure feed which was not added with the enrofloxacin or the salt thereof was taken as control.
As feed was added with different doses of enrofloxacin silver, the feed intake of the test pigs had no significant difference from that of a control group (See table 10 for results).
120 120-day-old healthy duroc-landrace-yorkshire hybrid pigs with similar body weights were divided into 4 test groups as shown in Table 11, and each group performed three repeats. Feed in each group was respectively added with 100 ppm of enrofloxacin zinc, enrofloxacin copper or enrofloxacin silver. The feed intake of the test pigs for 7 continuous days was subjected to statistics, the average daily feed intake was calculated, and influence of the normal application of the enrofloxacin zinc and the like on the feed intake of the pigs was evaluated. The pure feed which was not added with the enrofloxacin or the salt thereof was taken as control.
Statistical results of the continuous 7 days showed that as feed was added with enrofloxacin zinc and the like, comparing with a control group which was not added with a medicament, the feed intake behavior and the feed intake of the test pigs were normal, and the feed intake had no significant difference statistically (See table 12 for the results).
20 40-day-old piglets were divided into four groups with five pigs in each group as shown in Table 13, and the pigs were fed with enrofloxacin in different forms by gastric tubes in an amount of 10 mg/kg body weight respectively. Jugular venous blood collection was performed at 30 min, 1 h, 2 h, 4 h, 8 h, 12 h and 24 h after administration. Plasma was separated, the concentration of the enrofloxacin in the plasma in the different test pigs after administration was determined by high-performance liquid chromatography respectively, and whether the difference in the concentration of the enrofloxacin in the plasma in each test group after administration was significant or not and whether the elimination rule of the enrofloxacin in blood was consistent or not was subjected to statistical analysis.
The concentration and the elimination rule of the enrofloxacin and ciprofloxacin in the plasma of the test pigs in each test group after administration are as shown in Table 14. The results showed that the peak values of the plasma concentrations of all the test groups were similar, and the elimination law was consistent, indicating that the salts formed by the enrofloxacin and metal ions, such as zinc, copper, silver and the like did not affect the absorption and metabolism processes of the enrofloxacin in vivo.
60 30-day-old weaned piglets were divided into six groups with 10 pigs in each group as shown in Table 15, feed was respectively added with enrofloxacin in different forms, and free feed intake was performed. The 33-day-old pigs were intramuscularly injected with pathogenic escherichia coli, the diarrhea and deaths of the pigs were observed, continuous observation was performed for one week, the onset and deaths were subjected to statistics, and the protection effects of the enrofloxacin in different forms against the pathogenic escherichia coli in the artificial infection were compared. Pure feed which was not added with the enrofloxacin in any form was taken as a control group, wherein one portion of pigs in the control group were intramuscularly injected with the pathogenic escherichia coli and was taken as the control group without administration but with challenge (the fifth group), and the remainder were not intramuscularly injected with the pathogenic escherichia coli and was taken as the control group without administration and without challenge (the sixth group).
escherichia coli
escherichia coli
escherichia coli
escherichia coli
escherichia coli
After artificial infection with an escherichia coli SGD strain, all the test pigs in the control group without administration but with challenge (the fifth group) showed diarrhea, wherein 6 pigs died in the test period, while all the test pigs in the control group without the administration and without challenge (the sixth group) grew normally without diarrhea and death. All the medication administration groups showed complete protection effects against escherichia coli artificial infection (See table 16 for the results).
| Number | Date | Country | Kind |
|---|---|---|---|
| 201310160828.9 | May 2013 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2013/075325 | 5/8/2013 | WO | 00 |
