A SINGLE vaccination against the principal bacterium from respiratory disease in cattle, Mannheimia haemolytica (MH), at feedlot entry has been shown to lift average daily weight gains in non-backgrounded stock.
The research, undertaken by Charles Sturt University animal sciences student Liam Mowbray, aimed to delve into the health and production outcomes of using the single vaccination at induction as an alternative to on-farm and backgrounding vaccination.
The latter has long been known to reduce the incidence of bovine respiratory disease, or BRD, during subsequent time in the feedlot but there has been little control trial work done on the alternative.
Mr Mowbray gave an overview of his work at the recent Graham Centre Livestock Forum.
ALSO SEE:
He explained BRD was a non-specific respiratory disease in cattle, caused by stress from mixing, handling, restraint and transport allowing pathogens in.
It's typically seen as coughing, discharge and wheezing in cattle and estimated to cost the feedlot industry $40 million each year in drug expenses, mortality and loss in average daily gain.
Currently in Australia, there are commercially available vaccines for MH and bovine herpes virus-1 (BHV-1).
The trial
A randomised double-blind control trial was conducted using 1571 head of cattle of mixed sex, breed, origin, age and feedlot entry weight at a commercial feedlot in South East Queensland.
Cattle were allocated to one of three treatment groups - a control, single vaccination with Bovilis MH and single vaccination with Bovishield.
All cattle also received an intranasal modified live BHV-1 vaccine and a pour-on fly control treatment.
They were fed a total mixed ration for 60 to 70 days.
Overall the incidence of clinical BRD during the trial was 1.65 per cent, which was quite low, Mr Mowbray said.
Distribution was spread evenly between the three groups.
"Because of that low incidence we couldn't make statistical conclusions about the effects of single vaccination on the incidence of BRD, but what we did find was an increase in average daily gain among both vaccinated groups compared to the control group," he said.
"This was statistically significant in the Bovilis group, but not so much in the Bovishield group."