Brazilian study shows how small changes on farms can lower stress levels of cattle.
Corrals are used on livestock farms around the world to round up the animals when they need to be weighed or vaccinated. Setting up these corrals so that the cow has nothing to be paranoid about makes the cows far less likely to have a mental and be hard to handle.
So what makes a cow jumpy and hard to manage? Splashes of colour, water puddles, noisy interactions, dogs and cattle prods. Things that pretty much everyone is nervous of. Getting rid of these factors can dramatically reduce the cattle’s experience of stress.
Maria Lima of the Instituto de Zootecnia Sertãozinho in Brazil, says best practices are not standard in the construction of the traditional corrals used on Brazilian farms. Facilities are often inadequate, and farm workers know little about how to properly handle cattle. Even minor changes in a corral structure and better handling methods can affect the behaviour and stress levels of cattle.
The study took place on two commercial cattle farms in Brazil using a type of humpbacked Zebu breed called Nellore. This type of cow is known to be more temperamental than other cattle breeds. They can become quite aggressive when raised in extensive farming systems.
The corrals on the farms included wooden restraining devices and head stanchions and were surrounded by 1.8 metre-high wood board fencing. Cows were restrained in a squeeze chute by head holders that exerted light pressure on the neck of the animals.
Lima’s team studied the behaviour of the animals before and after specific interventions were put in place. Blood samples were drawn to measure the levels of the stress hormone cortisol. This indicated how stressed the animals were during handling.
Interventions incorporated into the corral included the installation of a solid panel to block the cows’ view of the handler when he was working within the path of the animals’ flight zone. Bright objects or ones with definite colour contrasts were removed. Water puddles were filled with dirt. Shadowy or dark areas with a high contrast between light and dark were also cut out.
Handlers received one-off training on how to work calmly and quietly with the animals. They were instructed not to shout, push or hit the cows, or to use dogs or electric prods. The handlers had to walk slowly to move the cows. They were also advised to use only flags to encourage the flow of animals.
The blood samples taken show that the cortisol levels of cows handled in the usual way was on average 60.4 ng/mL. It dropped to 41.03 ng/mL thanks to the improved methods. The percentage of calm cows during restraint in the chute increased from 42 percent for the usual methods to 68 percent for the improved corral-handling method.
“Minor changes made in the corral and the adoption of good handling practices reduced agitation during restraint in the squeeze chute, the time spent for blood collection, and cortisol release,” says Lima.
So there you go. Happy cows, happy burgers. Or something like that.