Numnuts for cattle – proof of concept study

Summary

Forty eight entire Holstein Friesian male weaned calves approximately 13 weeks were group housed in large straw-bedded pens for 2 weeks to acclimatise.  Calves were weighed and randomly assigned to one of three groups, with groups balanced for weight.  Average weight was 91Kg and the range was 45 to 130 Kg. There were sixteen calves in each treatment group:  1 Handled Controls, 2. Band with no analgesia, 3. Band with 10 ml Lignocaine 2% (LA) centrally injected between the two spermatic cords proximal to the band.  10 mL was chosen as the maximum practical safe dose of lignocaine.  The Handled Control calves were re-used throughout the experiment to make up a 4th treatment group (Band + 2 LA) where a band was applied and 5ml of 2% lignocaine injected carefully into each spermatic cord proximal to the band. The two cryptorchid calves were excluded, so n = 14 in this group.

Calves were castrated with a standard band (LG-Bands) applied to the neck of the scrotum using a standard tri-pronged applicator (LG-Bander).  Calves in the LA groups were then injected immediately proximal to the band between the band and the abdomen, with 10 ml of 2% Lignocaine using a 10 ml syringe and a 20 gauge 1" needle.  Calves in the Band LA group had the entire volume injected centrally in the neck of the scrotum. Calves in the Band + 2LA group had 5ml LA injected into each spermatic cord.

After treatment the behaviour of the calves was digitally recorded for a minimum of 3 hours. This footage was delivered to CSIRO, Armidale for Behavioural analysis. The behavioural analysis is commercial in confidence and may be released before May 2018.