Pretoria - A study done by the University of Pretoria (UP) has shown that vitamin C and probiotics could help farmed chickens cope better with heat stress.
“Our findings need to be substantiated through replicated production studies with larger numbers of birds, which is the next stage of our study,” said Joseph Chamunorwa, head of the anatomy and physiology department at the Faculty of Veterinary Science.
As global warming turns up the heat, ascorbic acid (vitamin C) and probiotics added to the feed of chickens raised for meat on small-scale farms in South Africa could help them cope better with heat stress.
Chamunorwa said this simple solution – although yet to be tested on large numbers of birds – has produced promising results in initial research on chickens raised during the hot summer season of 2022.
Chamunorwa is part of a UP research team investigating nutrition-based solutions for the growing threat of heat stress among chickens at small-scale farms.
Heat stress is already a major factor in losses in the poultry meat industry – as was seen earlier this year when thousands of birds on commercial farms died during air conditioning failures linked to load shedding.
However, it is specifically small-scale farmers whom the UP researchers seek to assist, as global warming rises.
Chamunorwa said chickens (and in fact all bird species) do not have sweat glands and their normal cooling mechanisms are behavioural. One of the most important is respiration – chickens pant so heat can move out of their bodies via their lungs and air sacs.
If conditions are simply too hot for them, intensively farmed chickens experience heat stress and then oxidative stress, which can damage their cells, tissue and organs, impairing their health, inhibiting their growth and potentially causing death.
Ascorbic acid is known to inhibit the oxidation process, while yeast probiotics have both antioxidant and anti-stress characteristics. The UP research team therefore set out to evaluate the effectiveness of these two elements in mitigating the damaging effects of oxidative stress on chickens exposed to heat stress under natural conditions.
They carried out their experiment on 56-day-old chicks divided into four groups of 14. For the next 35 days, the control group received standard chicken feed, and the chicks in the other three groups received either the probiotic or the ascorbic acid or both.
While the control group experienced the negative effects of heat stress throughout the study, results for the other three groups were encouraging.
More details about the study and its findings can be found in the Animal Gene journal article titled “Effects of probiotic and ascorbic acid on oxidative gene damage biomarker, heat shock protein 70 and interleukin 10 in broiler chickens exposed to heat stress”.
Pretoria News