The effect of antibiotics and acidifier treatment on the count of lactobacillus SP., E. Coli and clostridium SP. In the intestine of chickens

الملخص EN

The effect of addition of some commonly used antibiotics and acidifier on the total bacterial count of defined intestinal micro flora as Lactobacillus sp., E.

coli, and Clostridium sp.

with special reference to Cl.

perfringens was studied.

Two antibiotic doses were used : from 14-16th day of age and again from 29th -31st day of age.

The second course was followed by an acidifier for 3 days Results showed that doxycycline and amoxicillin had the inhibitoriest effects on Lactobacillus sp.

This inhibitory effect was more pronounced if an acidifier was used after these antibiotics than if they were used alone.

Cephradin, spiramycin, doxycycline, tylosin, floramphenicol and enrofloxacin showed good inhibitory effects on E.

coli.

This result concerning E.

coli cannot be taken as a model of recommendation because the continuous change in the drug resistance of this bacterium.

Spiramycin, cephradin, amoxicillin, doxycycline, tylosin, lincospectin and enrofloxacin were effective against Cl.

perfringens and other Clostridium sp.

The antibacterial action of these antibiotics was increased if an acidifier was used afterwards.

One week after the end of the antibiotics and acidifier treatment, there was a decrease in Lactobacillus sp., E.

coli and Clostridium sp.

counts in the intestine with one log lower (104) than that count in case of antibiotics without acidifier (105).

This finding encourages us to recommend usage of acidifiers for chicken especially after antibiotic courses to prolong their antibacterial activity.