EARLY results in a study looking at the impact of shade on feedlot production, have found significant gains in using waterproof shelters over shade cloth.
Funded by Meat & Livestock Australia, the University of New England study has been comparing the performance of three different pen setups at its Tulimba Feedlot – looking at a plastic waterproof cover, shade cloth and unshaded.
Talking the Australian Lot Feeders’ Association’s shade webinar yesterday, UNE researcher Dr Angela Lees said one of the main aims of the study was to gather data for southern feedlots, with Tulimba based in the colder New England region of New South Wales and Bos taurus cattle used in the pens.
“The majority of the feedlot shade research has happened in Queensland, in tropical and sub-tropical environments,” Dr Lees said.
“Because of this there’s always questions about the benefits of shade to southern or more temperate environments. Although we’re still in an active data analysis phase, we’ve really made some progress towards answering some of those questions in the study.”
Weight gains in waterproof shade
Two 360 head cohorts were inducted into Tulimba a month apart – one at the end of December 2020 and another at the end of January 2021.
They were fitted with rumen boluses to send to check their temperature every 10 minutes and an on-site weather station was also updating in real time. Behavioural observations, including posture, rumination, shade utilisation and panting score were taken four-times-a-day.
With the separate induction times, one cohort was fed for 104 days and the other was fed for 109 days before they were sent to Qld for processing. Weight gains were measured and independent Meat Standards Australia (MSA) assessors studied the carcasses.
Dr Lees said one of the main findings of the study so far was the increased weight gains of cattle in the waterproof pens. Cattle in waterproof pens also outperformed the others in hot carcass weight and rib-fat measurements.
“We know the cattle under the waterproof treatment were substantially heavier than those in the shade cloth and unshaded pens. We had a 10kg difference in final liveweight between waterproof and shade cloth alone,” she said.
Production benefits were more related to the management of wet pens rather than heat stress
“We also observed an increase in average daily gain until exit the cattle in waterproof pens were more efficient with the gain-to-feed ratio.
“I think a lot of the production benefits were more related to the management of wet pens rather than heat stress.”
With the cattle in waterproof pens performing better at the processor, Dr Lees further quantified the results to MLA last month.
“Assuming a price of $9.00/kg HSCW, our data showed lot feeders would gross over $63/head more for the cattle under the waterproof shelter compared to the no shade or shade cloth treatments,” she said.
Dr Lees said one of the issues with the study was the wet and cool summer in 2021 – which did not test too many heat-stress barriers.
“It was one of the coolest and wettest summers I have experienced in my time in Armidale,” she said.
“We still experienced some nice warm days, but most of the summer was spent in these cool and mild conditions.”
Waterproof shade gives animal welfare benefits
While the objective production gains were easy to see, Dr Lees said the behavioural observations also revealed animal welfare benefits.
“Looking at the panting score data, the waterproof cattle had lower panting scores than the shade cloth cattle, who had lower panting scores than the unshaded cattle,” she said.
“Even though we had the cool and mild summer, we still had enough warm days to see trend and extract some good panting score data – which showed those animal welfare outcomes.”
Dr Lees said shade utilisation was a lot higher in the waterproof pens than the others.
“Shade utilisation across both the shade cloth and waterproof pens was high on all the sunny days we experienced,” she said.
“But during the cool and wet conditions, the waterproof pens had a lot higher shade utilisation than the other pens.
“The waterproof pens were much drier and much less muddy during the cool and wet period. The top layer went to a clay that was like play doe, whereas the other pens had water laying around and became quite muddy.”
More study to come
More cattle were inducted into Tulimba in July last year on a 120 program, with the results still to be analysed.
Building sheds over the top of feedlot pens also comes at a significant and the cost/benefit analysis of building them is still to come.