Catching a killer — vibriosis
It wasn’t even smoko time, and already the Wrights were worried.
One June morning, the Wrights of Mt Spencer Station, 60 kilometres south-west of Mackay, yarded 570 shiny maiden heifers and remarked what good nick they were in. They were right; their composite heifers averaged around 330 kg liveweight and 3-3.5 body condition score (BCS). Within the first hour of pregnancy testing however, as empty after empty was called, the Wrights and their vet, Brendan Brieffies from Clermont Vet Surgery, were suspicious that something was amiss. The ‘empties’ yard looked different than normal: where usually there are predominantly grey brahmans, there was a cross section of the herd. By the time they broke for smoko, Raeleen Wright was already consulting her weight records from the previous years’ heifer cohort.
At the end of testing, only 41% of the maiden heifers were found to be pregnant; a low result compared with the previous year that were over 65% pregnant.
What would your first thought be? The season? Maybe these heifers are just a bit light?
That’s what Raeleen reckoned too, so she checked. These heifers were not significantly lighter than last year’s. Maybe a dodgy preg test? Brendan is accredited through the Australian Cattle Vets, and the Wrights are very confident in his diagnoses. “We can rely on what he says. The data we collect and calves on the ground always back up the testing”.
What about three-day sickness (bovine ephemeral fever)? It was a big year for it, and they’d seen some of the bulls down… Otherwise the bulls couldn’t cop the blame, as they had been through a full bull breeding soundness examination (BBSE) either at point of sale or the previous year, so they knew they were up to the job.
“I can’t emphasise enough, we had to stop hypothesising and get some evidence” says Raeleen.
The next week, Brendan returned to Mt Spencer to test the bulls and 15 heifers. No effect of three-day sickness was picked up in the bulls, and bloods and vaginal swabs were collected from the heifers to test for vibrio and pestivirus.
The results came back showing a vibrio infection in a high proportion of the herd. All the bulls on Mt Spencer are vaccinated for vibrio, so it was suggested that the culprit was a staggy steer. Maiden heifers do not go in the same paddock every year at Mt Spencer, and this year’s heifers had been in the boundary paddock, sharing a fence with cattle that were new to the area. This is likely how the disease was introduced. Brendan elaborated that “for vibrio, like any disease, a biosecurity plan is important. Knowing what’s in your herd, what’s coming in when you introduce new cattle or people, and having an idea of what’s next door is very influential in managing disease”.
The heifers were isolated from other cattle, and under recommendations from Brendan and consultant John Bertram, a vaccination program was implemented. All pregnant heifers were vaccinated with Vibrovax, as were 200 of the empties. Culling all the empties would have been an easier option, and 130 heifers were sold to a feedlot, but after significant investment in genetics in recent years Mt Spencer opted to retain some. Any mature pregnant cows were also vaccinated for vibrio, and this year’s maiden heifers will be vaccinated with Longrange Botulinum, Pestigard, Vibrovax and 7in1 prior to joining.
The negative pestivirus test confirmed previous tests indicating the herd’s naïve status. For this reason maiden heifers will continue to be vaccinated with Pestigard, which adds a significant amount to animal health costs, but Raeleen says “we can’t afford not to”, as pestivirus would have an even greater effect on herd productivity than vibrio.
The bulls that were running with the heifers at the time of infection were treated with Draxxn antibiotic to ensure no vibrio was retained, and all mature bulls were also treated with Erymycin antibiotic. This year all bulls on Mt Spencer will be vaccinated for three-day sickness as further insurance.
“Vibrio is the same as any disease. If you can catch it early there’s a good chance of managing it before it costs you a lot of money. At Mt Spencer we were able to pick it up pretty quick through the data, having data available is a massive tool.” – Brendan Brieffies from Clermont Vet Surgery
Raeleen sourced competitive vaccine prices by shopping around with multiple agents and encourages others to do the same. Mt Spencer spent approximately $20/head to manage the vibrio outbreak. This included nearly $20,000 on vaccines and antibiotics, and excluded mustering and handling costs. A 20% drop in pregnancy rate of maiden heifers cost the business 110 calves – based on today’s prices, in 2021 those weaners would have made nearly $90,000. Had such a proactive approach not been taken, that 20% loss could have spread across all 2500 breeders on Mt Spencer.
As Raeleen emphasises, “you don’t just sit on it for a year, you can’t assume it was the season. A year later, vibrio could be through the whole herd — test and find out”.
More information is available at futurebeef.com.au (search for ‘vaccinations’).
This article has been prepared by Peta Stockwell, beef extension officer located in Mackay, and has been previously published in the FutureBeef Beef Features in the Queensland Country Life and North Queensland Register.