Seguridad y respuesta serológica de una vacuna multivalente marcada frente a la ERB, administrada a terneros de cebo de 2-4 semanas de vida
Pere Ordis Pla1, MARC VILA2, MARTA GIBERT3, MARINA SOLÉ2, WOJCIECH PTAK2, MASSIMILIANO BARATELLI3, CARLOS MONTBRAU3, JOSEP SOLER4
(1)-Laboratorios Hipra, S.A. (2)-HIPRA, S.A (3)-HIPRA, S.A.
(4)-IRODSERVET SLP
BACKGROUND and OBJECTIVE:
Bovine respiratory disease (BRD) affects up to 61% of veal herds, with particularly high incidence in pre-weaned calves. This highlights the need for safe early-life vaccination. Recently, a new multivalent marker vaccine designed to protect cattle against BRD, has proven to be safe and efficacious in older calves. Evidence in younger animals remains limited. This study evaluated safety and serological responses when the vaccine was administered to veal calves at 2 to 4 weeks of age.
MATERIALS and METHODS:
Seventy-one veal calves (male and female) from a commercial Spanish feedlot, representing different origins and breeds, were enrolled in the study. Each calf received two intramuscular doses (2 mL) at 2–4 weeks of age, with a booster administered 21 days later. Animals were monitored from the first vaccination day(D0) until 12 weeks post-vaccination (W12). Safety assessments were performed in a subgroup of fifteen calves and included rectal temperature, systemic and local reactions, and general health observations, at D0, D0+4h, D1, D2, D20, D21, D21+4h, D22, and D23. Serum samples were collected at D0, D21, W6, and W12. TheW12. The immune responses were evaluated using commercial ELISA kits: BoHV-1 gB and gE (IDEXX), BVDV p80 (CIVTEST), and Total BVDV antibodies (IDEXX).
RESULTS:
No anaphylactic reactions were reported in any of the 71 vaccinated animals during the monitoring period. Within the safety subgroup, 33% of calves developed transient hyperthermia after the first dose and 30% after the second dose. None of the calves required specific treatment, and all recovered within three days, consistent with the expected range described in the Summary of Product Characteristics (SPC). No systemic or local adverse reactions beyond the anticipated transient fever were observed. Serology demonstrated 100% seroconversion to BoHV-1 gB by D21. At D0, 66.7% of the animals were gE-negative, and this status was reduced until W12, with 76.9% of animals remaining gE-negative. These findings are consistent with the vaccine profile and highlight the vaccine’s efficacy. In addition, robust BVDV-specific antibody responses were detected, with 100% seroconversion achieved by W6, confirming the vaccine’s immunogenicity in this age group.
CONCLUSIONS:
The administration of the multivalent marker vaccine in calves at 2–4 weeks of age demonstrated a similar safety profile to the standard (SPC) profile, reinforcing its potential role in early-life immunization strategies against BRD.
