An injection system comprising: - a bird restraint apparatus; and - an injection unit, wherein the bird restraint apparatus is operably connected to the injection unit, and wherein the bird restraint apparatus is configured to restrain a bird in a selected position relative to the injection unit, the injection unit comprising: a first needle assembly comprising a first injection needle and a first needle actuator (24, 27, 28) operably connected to the first injection needle, wherein the first needle actuator (24, 27, 28) is configured to move the first injection needle between an injection position and a retracted position along a first injection axis; a needle carriage operably connected to a carriage actuator (54; 350), wherein the first needle assembly is mounted on the needle carriage, wherein the carriage actuator (54; 350) is configured to rotate the needle carriage about a carriage axis between a standby position and an actuation position, wherein the first injection needle is configured to contact a bird restrained in the bird restraint apparatus when the needle carriage moves into the actuation position, and wherein the first injection needle is configured to be positioned subcutaneously in a bird restrained in the bird restraint apparatus when the needle carriage is in its actuation position and the first injection needle is in the injection position, characterized in that the carriage axis extends through the first injection axis. - a bird restraint apparatus; and - an injection unit, wherein the bird restraint apparatus is operably connected to the injection unit, and wherein the bird restraint apparatus is configured to restrain a bird in a selected position relative to the injection unit, the injection unit comprising: a first needle assembly comprising a first injection needle and a first needle actuator (24, 27, 28) operably connected to the first injection needle, wherein the first needle actuator (24, 27, 28) is configured to move the first injection needle between an injection position and a retracted position along a first injection axis; a needle carriage operably connected to a carriage actuator (54; 350), wherein the first needle assembly is mounted on the needle carriage, wherein the carriage actuator (54; 350) is configured to rotate the needle carriage about a carriage axis between a standby position and an actuation position, wherein the first injection needle is configured to contact a bird restrained in the bird restraint apparatus when the needle carriage moves into the actuation position, and wherein the first injection needle is configured to be positioned subcutaneously in a bird restrained in the bird restraint apparatus when the needle carriage is in its actuation position and the first injection needle is in the injection position, characterized in that the carriage axis extends through the first injection axis. a first needle assembly comprising a first injection needle and a first needle actuator (24, 27, 28) operably connected to the first injection needle, wherein the first needle actuator (24, 27, 28) is configured to move the first injection needle between an injection position and a retracted position along a first injection axis; a needle carriage operably connected to a carriage actuator (54; 350), wherein the first needle assembly is mounted on the needle carriage, wherein the carriage actuator (54; 350) is configured to rotate the needle carriage about a carriage axis between a standby position and an actuation position, wherein the first injection needle is configured to contact a bird restrained in the bird restraint apparatus when the needle carriage moves into the actuation position, and wherein the first injection needle is configured to be positioned subcutaneously in a bird restrained in the bird restraint apparatus when the needle carriage is in its actuation position and the first injection needle is in the injection position, characterized in that the carriage axis extends through the first injection axis. wherein the carriage actuator (54; 350) is configured to rotate the needle carriage about a carriage axis between a standby position and an actuation position, wherein the first injection needle is configured to contact a bird restrained in the bird restraint apparatus when the needle carriage moves into the actuation position, and wherein the first injection needle is configured to be positioned subcutaneously in a bird restrained in the bird restraint apparatus when the needle carriage is in its actuation position and the first injection needle is in the injection position, characterized in that the carriage axis extends through the first injection axis.