PMID- 22978593
OWN - NLM
STAT- MEDLINE
DCOM- 20130208
LR  - 20131121
IS  - 1466-1799 (Electronic)
IS  - 0007-1668 (Linking)
VI  - 53
IP  - 3
DP  - 2012
TI  - Serum and tissue concentrations of doxycycline in broilers after the 
      sub-cutaneous injection of a long-acting formulation.
PG  - 366-73
LID - 10.1080/00071668.2012.701004 [doi]
AB  - 1. The antibacterial agent doxycycline hyclate (Dox) is usually administered to 
      broilers in drinking water or as a feed supplement. Parenteral injection is not 
      the usual route for administration, so a long-acting formulation (Dox-LA) was 
      tested to evaluate if serum concentrations can achieve the 
      pharmacokinetic/pharmacodynamic (PK/PD) ratios regarded as adequate for the drug. 
      2. A poloxamer-based matrix was used to provide Dox-LA. Serum and tissue 
      concentrations of Dox vs time were determined in two day-old broilers after 
      subcutaneous (SC) injection of Dox-LA or oral administration of a single bolus of 
      aqueous Dox (Dox-PO), at a dose of 20 mg/kg. Weight gain, feed conversion rate, 
      haematological variables, aspartate aminotransferase and alanine aminotransferase 
      activities, blood urea and creatinine were determined and compared for Dox-LA 
      with Dox-PO and non-medicated controls. 3. Dox-LA had a high relative 
      bioavailability (1200%). Maximum serum concentrations were not statistically 
      different (5.1 +/- 1.1 microg/ml for Dox-LA and 6.1 +/- 1.4 microg/ml for Dox-PO), but 
      half-life of Dox-LA was much greater than the value obtained for Dox-PO (73.0 +/- 
      0.9 h and 2.0 +/- 0.02 h, respectively). Tissue concentrations were higher, and 
      stayed higher for longer periods in the Dox-LA group. 4. In conclusion, 
      considering the minimum effective serum concentration against Mycoplasma spp is 
      0.5 microg/ml, a dose-interval of 180 h can be achieved with Dox-LA, but only for 24 
      h after Dox-PO. Better PK/PD ratios for Dox-LA should result in improved clinical 
      outcomes compared with Dox-PO.
FAU - Gutierrez, L
AU  - Gutierrez L
AD  - Departamento de Fisiologia y Farmacologia, Facultad de Medicina Veterinaria y 
      Zootecnia, Universidad Nacional Autonoma de Mexico, Av. Universidad 3000, 
      Delegacion Coyoacan, Ciudad de Mexico C.P. 04510.
FAU - Vargas-Estrada, D
AU  - Vargas-Estrada D
FAU - Rosario, C
AU  - Rosario C
FAU - Sumano, H
AU  - Sumano H
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Br Poult Sci
JT  - British poultry science
JID - 15740290R
RN  - 0 (Anti-Bacterial Agents)
RN  - N12000U13O (Doxycycline)
SB  - IM
MH  - Administration, Oral
MH  - Animals
MH  - Animals, Newborn/metabolism
MH  - Anti-Bacterial Agents/administration & dosage/blood/*pharmacokinetics
MH  - Biological Availability
MH  - Chickens/*metabolism
MH  - Doxycycline/administration & dosage/blood/*pharmacokinetics
MH  - Half-Life
MH  - Injections, Subcutaneous/veterinary
MH  - Microbial Sensitivity Tests
MH  - Tissue Distribution
EDAT- 2012/09/18 06:00
MHDA- 2013/02/09 06:00
CRDT- 2012/09/18 06:00
PHST- 2012/09/18 06:00 [entrez]
PHST- 2012/09/18 06:00 [pubmed]
PHST- 2013/02/09 06:00 [medline]
AID - 10.1080/00071668.2012.701004 [doi]
PST - ppublish
SO  - Br Poult Sci. 2012;53(3):366-73. doi: 10.1080/00071668.2012.701004.