[Intradermal versus intramuscular vaccine application in suckling piglets - Comparison with regard to dermal...

The aim of this study was the scientific evaluation of an intradermal vaccination method in comparison to an intramuscular vaccination against Mycoplasma hyopneumoniae in suckling piglets with regard to skin reactions, performance parameters and procedural aspects. Possible effects on animal welfare should be deduced.

Under field conditions, 672 suckling piglets in three batches were vaccinated; 338 intradermally and 334 intramuscularly. In addition to a detailed scoring of the integument, the injection site with the local reaction was evaluated, scoring the swelling size (score 0-5), and rubor and incrustation (score 0-3). Moreover, piglets were weighed individually 1 day before vaccination and 8 days later. In addition, the time required for each vaccination was documented.

On the first day after vaccination, 71.3 % of the intramuscularly vaccinated piglets and 2.7 % of the intradermally vaccinated piglets displayed no swelling at the vaccination site. No differences remained by the 7th day after vaccination. Daily weight gain did not differ significantly between the piglets in the intramuscularly (248 g) and intradermally (258 g) vaccinated groups. Intradermal vaccination took a mean of 11 seconds per piglet, while 17 seconds were required for intramuscular vaccination.

In this first study, no negative effects of the intradermal vaccination on performance parameters and no long-standing skin reactions were detected in the suckling piglets. Skin reactions were related to the desired immune reaction of the intradermal vaccination, but were no longer present after 7 days. Moreover, with regard to procedural aspects, the intradermal vaccination offered time saving advantages. To evaluate further possible effects on animal welfare, further analyses via video recordings are required.