Data crunching 100-day grainfed study

As part of a study, conducted with support from Harvey Beef, MLA and the Australian Meat Processor Corporation (AMPC), scientists measured stress indicators in cattle to determine the impact of handling conditions and new environments such as feedlots and processing plants.

Associate professor David Miller and Dr Fiona Anderson were the driving forces behind the project.

"Harvey Beef came to us and asked us to look at their 100-day grainfed program," Dr Miller said.

"There is increasing awareness of the value of welfare and they are very interested in promoting their brand in terms of ethics, welfare and social license, and also in the production benefits of monitoring welfare.

"They wanted to highlight points where improvements may need to be made, as well as areas where good things were already being done to validate their processes."

Dr Miller said from his perspective, welfare monitoring had been seen as a negative thing in the past, especially in relation to farming, because it was seen as just looking for negative welfare.

"But I think that is changing now," he said.

"Farmers, producers and others like Harvey Beef are looking at it from the perspective of trying to promote the positive aspects of welfare in production, and improve where they can - how to do that was the question we wanted to answer.

"They were particularly interested in highlighting timepoints during the 100-day finishing process, both good and bad, but also looking at variation and what impact that might have on individual animal performance (e.g. weight gain and meat quality)."

The project followed the stress levels of 240 cattle across the duration of Harvey Beef's 100-day grainfed program at a feedlot in the South West, with measurements taken at induction on day zero, as well at day 30, 70 and 100, prior to slaughter.

"Apart from the feedlot operations taking weights, ear tagging, and so on, we were there collecting blood samples and taking a number of behavioural measurements at those time points," Dr Miller said.

"Through blood sampling we measured various physiological indicators, not only of 'stress' per se, but also things like muscle damage, nutrition, immune status - all of which are associated with animal welfare.

"Along with that, we were also looking at behavioural markers such as docility, crush scores, and flight times."

The cattle which were selected for the project had all come from the same origin and similar genetic backgrounds, with minimal handling experience prior to transportation, which helped provide a balanced base for the project to work from.

"We didn't want to compare cattle that had been handled a lot to cattle that hadn't prior to induction to the feedlot," Dr Anderson said.

"So we tried to control as much as we could to ensure the cattle had similar experiences."

When the cattle arrived at the feedlot following transport, their stress response was measured.

"We wanted to see what was the same, or different, to how they behaved once they were in the feedlot," Dr Anderson said.

"We saw them as they were inducted into a novel environment so I guess looking at how animals respond to a novel environment was the premise of the study."

The main 'stress' point of the 100-day process was one of the most interesting findings.

"There are anecdotal theories that pre-slaughter is the most stressful period for an animal but we didn't find that," Dr Miller said.

"Actually we found the most stressful period in the process for an animal is the induction process, as indicated by the blood samples and behaviours we were looking at."

Dr Anderson said it was important to be careful, however, when using the term 'stress' when describing the findings at induction.

"Anything out of the norm will cause a short-term stress response," she said.

"One of our major findings was that for this particular feedlot and processing plant, the overall levels of stress were low to moderate in terms of how stressed cattle can be, and when we say induction was the most stressful period, it was just more stressful than the rest of the time points - but at no point did cattle ever demonstrate a high level of stress during the 100-day process.

"So in many ways it was actually showing that handling techniques at the feedlot, during induction, during transport and also in the pre-slaughter period at the processing plant were all very good because, in terms of how stressed cattle can be, these cattle were not very stressed at all."

A significant finding was that the cattle also improved over time.

"Throughout that 100-day process their stress markers improved," Dr Miller said.

"And that backed up the idea that this finishing process is not only about getting them to appropriate weight, but also about getting the animals in a condition where they're not going to be stressed prior to slaughter, especially if they're coming from extensive farming systems where their interactions with humans and yard environments have been quite limited.

"They adapted quite well to their environment and started doing that quickly.

"We found markers like flight speed showed a significant decrease by day 30, and continued to decline thereafter."

Dr Miller said there was variation among the cattle as well.

"That variation was one of the main things we were looking into because that variation might have been able to predict how those animals would perform throughout the process and maybe their ultimate eating quality as well."

Dr Miller mentioned temperament variability which was picked up at induction did indeed play out in terms of difference in performance and eating quality.

"The animals which were in the poorer range of temperament grew about half a kilogram per day slower than those in the better range of temperament," Dr Miller said.

"We also found their carcase weights were affected by the temperament as was meat tenderness."

When it comes to how this research is relevant to cattle producers back on-farm, a growing preference for selecting quiet breeding stock already has producers on the right track.

"Selecting for better temperament and making management choices related to temperament are probably the main factors which would be applicable on-farm," Dr Miller said.

"The heritability of things like temperament are low to moderate, and they are fairly variable as well, but there are some producers who say they have success with selecting through the docility EBV.

"But is that a simple fix, or do management changes and monitoring come into it as well?

"Those are the sorts of things worth thinking about on-farm."

Dr Anderson said that this study had also raised more questions and highlighted areas where more work has to be done.

"We're not saying farmers should select for temperament because it's going to make you 'x' amount of dollars, but certainly we have highlighted how important temperament is, as well as best practice cattle handling," Dr Anderson said.

What the study has done is effectively proven low stress handling in the feedlot situation is valuable. That translates back to the benefits of good stock management on-farm so well-tempered cattle are heading into the feedlot system.

"I guess it reinforces that best-practice management is actually going to translate," Dr Anderson said.

"And I think animal welfare is only going to become more important going forward.

"So it's good for processors and feedlots to have the sort of foresight to run projects like this to see what areas can be improved upon."

There is more research to do in this space, though the Murdoch team have no follow-up work planned as yet.

What might be next?

Putting a dollar value on temperament would be an interesting study to look at.

"Fortunately the two go well together," Dr Anderson said.

"It's not looking at welfare for welfare's sake or meat quality for meat quality's sake, because they are both inter-twined. Research findings like this are good for everybody involved."