A non-inferiority study evaluating a new extended-release preparation of tilmicosin injected subcutaneously vs. ceftiofur administered intramammary, as dry-cow therapy in Holstein Friesian cows
Por:
Ortega, Esteban, Alfonseca-Silva, Edgar, POSADAS, EDUARDO, Tapia, Graciela, Sumano, Hector
Publicada:
1 nov 2020
Categoría:
Veterinary (miscellaneous)
Resumen:
Background: A new, extended long-acting tilmicosin (TLAe) preparation
was tested against intramammary ceftiofur (CEF) using a non-inferiority
trial model during dry-cow therapy (DCT) in a farm with high bovine
population density and deficient hygiene application.
Objectives: To evaluate the possibility that TLAe administered
parenterally can achieve non-inferiority status compared to CEF
administered intramammary for DCT.
Methods: Cows were randomly assigned to TLAe (20 mg/kg subcutaneous; n =
53) or CEF (CEF-HCl, 125 mg/quarter; n = 38 cows) treatment groups.
California mastitis testing, colony-forming unit assessment (CFU/mL),
and number of cases positive for Staphylococcus aureus were quantified
before DCT and 7 d after calving. A complete cure was defined as no
bacteria isolated; partial cure when CFU/mL ranged from 150 to 700, and
cure-failure when CFU/mL was above 700.
Results: TLAe and CEF had overall cure rates of 57% and 53% (p> 0.05)
and S. aureus cure rates of 77.7% and 25%, respectively (p < 0.05).
The pathogens detected at DCT and 7 days after calving were S. aureus
(62.71% and 35.55%), Staphylococcus spp. (22.03% and 35.55%),
Streptococcus uberis (10.16% and 13.33%), and Escherichia coli (5.08%
and 15.55%). Non-inferiority and binary logistic regression analyses
revealed a lack of difference in overall efficacies of TLAe and CEF.
Apart from S. aureus, S. uben's was the predominant pathogen found in
both groups.
Conclusions: This study is the first successful report of parenteral DCT
showing comparable efficacy as CEF, the gold-standard. The extended
long-term pharmacokinetic activity of TLAe explains these results.
Filiaciones:
Ortega, Esteban:
Univ Nacl Autonoma Mexico, Sch Vet Med, Dept Anim Prod Ruminants, Mexico City 04510, DF, Mexico
Alfonseca-Silva, Edgar:
Univ Nacl Autonoma Mexico, Sch Vet Med, Dept Microbiol & Immunol, Mexico City 04510, DF, Mexico
POSADAS, EDUARDO:
Univ Nacl Autonoma Mexico, Sch Vet Med, Dept Anim Prod Ruminants, Mexico City 04510, DF, Mexico
Tapia, Graciela:
Univ Nacl Autonoma Mexico, Sch Vet Med, Dept Genet & Biostat, Mexico City 04510, DF, Mexico
Sumano, Hector:
Univ Nacl Autonoma Mexico, Sch Vet Med, Dept Physiol & Pharmacol, Ave Insurgentes Sur 3000, Mexico City 04510, DF, Mexico
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