Randomized noninferiority field trial comparing 2 first-generation cephalosporin products at dry off in quarters receiving an internal teat sealant in dairy cows.
The study objective was to compare 2 commercial dry cow mastitis products at the quarter level, with concurrent internal teat sealant application, evaluating the cure risk difference, odds of a cure, odds of a new intramammary infection (NIMI) during the dry period, and risk for a clinical mastitis (CM) case between calving and 60d in milk (DIM). A total of 590 cows (2,360 quarters) from 8 commercial dairy herds in Italy were enrolled and randomized to 1 of the 2 treatments at dry off: Cefovet A (CF; 250mg of cephazoline; Merial Italia SpA, Milan, Italy), and Cepravin (CP; 250mg of cephalonium dehydrate MSD Animal Health Srl, Segrate, Italy). Quarter milk samples were collected before dry cow therapy treatment at dry off, 2 to 9 DIM, and 10 to 17 DIM. Quarter milk samples from CM cases were collected during the first 60 DIM. Noninferiority analysis was used to evaluate the effect of treatment on the risk difference of a bacteriological cure during the dry period, the primary outcome. The odds of cure, developing a NIMI during the dry period, and the risk of a CM event within 60 DIM were evaluated with multivariable logistic regression and hazard analysis, respectively. The overall crude quarter-level prevalence of NIMI at dry off was 15.3%. The most common pathogen isolated from milk samples at dry-off was coagulase-negative staphylococci. Noninferiority analysis showed no effect of treatment on the risk difference for a cure between dry off and both postpartum samples, difference was 0.013. The least squares means from the multivariable model evaluating the odds of cure was 94% for CF and 95%for CP. We observed no effect of treatment on the odds for the presence of a NIMI at 2 to 9 DIM (least squares means: CF=0.09 and CP=0.07), nor did we note a difference in risk of experiencing a CM event between calving and 60 DIM (hazard ratio=0.8). In conclusion, no difference was observed between the 2 products evaluated when assessing the aforementioned outcomes in quarters also receiving an internal teat sealant.
Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, Italy.
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Ospina
Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, via Celoria 10, 20133 Milan, Italy.
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Rota
Dipartimento di Scienze Veterinarie per la Salute, la Produzione Animale e la Sicurezza Alimentare, Università degli Studi di Milano, via Celoria 10, 20133 Milan, Italy.
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Locatelli
Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, via Celoria 10, 20133 Milan, Italy.
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Colombo
Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, via Celoria 10, 20133 Milan, Italy.
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Pollera
Istituto Zooprofilattico Sperimentale del Lazio e della Toscana Mario Aleandri, Via Appia Nuova 1411, 00178, Rome, Italy.
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Giacinti
Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, via Celoria 10, 20133 Milan, Italy.
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Bronzo
Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, via Celoria 10, 20133 Milan, Italy.
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Casula
Practitioner, via S. Bernadette 31, 00167 Rome, Italy.
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Arpinelli
Practitioner, via Guido Reni 96/66, 10136 Turin, Italy.
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Brossette
Studio Associato Veterinari Bergamaschi via Verdi 8, 24060 Castelli Calepio, Bergamo, Italy.
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Facchi
Embryovet Cascina Bosco 6, 25028 Verolonuova, Brescia, Italy.
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Patelli
Armigio via Donatori di Sangue 36, 25020 San Paolo, Brescia, Italy.
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Ruggeri
Istituto Zooprofilattico Sperimentale delle Venezie, Sez. Terr. Vicenza, 36100 Vicenza, Italia.
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Barberio
Merial Italia SpA, Viale Bodio, 37, 20158 Milan, Italy.
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Potenza
Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, Italy.
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Nydam
Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, Italy; Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, via Celoria 10, 20133 Milan, Italy. Electronic address: pm389@cornell.edu.
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Moroni
D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002417:Cattle; D002511:Cephalosporins / Q000627:therapeutic use; D005260:Female; D007774:Lactation; D008321:Mammary Glands, Animal / Q000187:drug effects; D008414:Mastitis, Bovine / Q000453:epidemiology*; D008892:Milk / Q000187:drug effects
D000900:Anti-Bacterial Agents; D002511:Cephalosporins
dry cow therapy; first-generation cephalosporin; intramammary infection; randomized noninferiority field-trial