Efficacy dose determination study of tilmicosin phosphate in feed for control of pneumonia caused by Actinobacillus pleuropneumoniae in swine.
OBJECTIVE
To determine the effective dosage of tilmicosin phosphate when fed to pigs for the control of pneumonia attributable to Actinobacillus pleuropneumoniae.


METHODS
Randomized complete block design, with initial weight as the blocking factor.


METHODS
Seeder pigs were used to infect clinically normal male and female pigs weighing between 13.6 and 36.3 kg at each of 4 trials.


METHODS
Five doses of tilmicosin phosphate (0, 100, 200, 300, and 400 micrograms/g) were fed to pigs for 21 days. Pigs received experimental feeds 7 days before the seeder pigs were placed into pens. Feeding continued for an additional 14 days, with seeder pigs removed 3 to 8 days after placement. All pigs were euthanatized and necropsied, with lung bacterial flora and percentages of pneumonic involvement determined.


RESULTS
Improvement in clinical impression score, daily rectal temperature, and weight gain were seen for all doses of tilmicosin, compared with controls. For the same variables, tilmicosin administered at 200 to 400 micrograms/g resulted in improvements over the 100 micrograms/g dose.


CONCLUSIONS
Data indicate that tilmicosin phosphate fed to pigs at 200 to 400 micrograms/g is effective in controlling and preventing A pleuropneumoniae-induced pneumonia, when administered in feed for 21 days.
Moore
G M
GM
Elanco Animal Health Animal Science Field Development Research, Eli Lilly and Co, Greenfield, IN 46140, USA.
Mowrey
D H
DH
Tonkinson
L V
LV
Lechtenberg
K F
KF
Schneider
J H
JH
D000189:Actinobacillus Infections / Q000517:prevention & control / Q000662:veterinary*; D016977:Actinobacillus pleuropneumoniae; D000821:Animal Feed; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001831:Body Temperature / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D005260:Female; D005527:Food, Fortified; D018942:Macrolides; D008297:Male; D018410:Pneumonia, Bacterial / Q000517:prevention & control / Q000662:veterinary*; D013552:Swine; D013553:Swine Diseases / Q000517:prevention & control*; D015645:Tylosin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D015430:Weight Gain / Q000502:physiology
D000900:Anti-Bacterial Agents; D018942:Macrolides; C052319:tilmicosin; D015645:Tylosin