English to Spanish Science Livestock / Animal Husbandry field study - vaccines

Alguna opción diferente a "se les colocó un collar en el cuello"? Gracias!

The birds in Group 5 were sham-inoculated by the SQ route with 0.2ml of Marek’s disease vaccine diluent, Lot DJ544 Exp.
SEP17, before they were placed in the isolation units.
On Study Day 27, all birds were neck-banded by un-blinded personnel and reduced to 30 birds per group (10 birds per unit) using a randomization schedule and the extra birds were terminated.

On Study Day 25, the number of birds was reduced to 10 per unit (30 birds per group) for Groups 1-5 using a randomization schedule and all the extra birds were terminated.
The remaining birds were neck-banded for individual identification.