Waste from the winemaking process shows promise as a replacement for antibiotics to keep broiler chickens healthy.
By Amelia Genis, senior journalist at African Farming and Landbouweekblad
Researchers in the United States have found that fermented grape waste has almost the same effect on chickens’ gut health and growth performance as antibiotics. According to a scientific article published in npj Biofilms and Microbiomes and an article on the website Anthropocene, American broiler producers are trying to move away from antibiotics because of concerns that poultry could develop resistance to them.
Although antibiotics can promote growth by combating harmful bacteria in chickens’ intestines and preventing poor growth performance, alternative solutions are needed. The researchers based their study on previous research showing that grape waste has the potential to combat bacteria.
They divided 126 chickens into different feed treatment groups. Some of the chickens received a diet containing 30% rice bran, which is known to cause intestinal inflammation, while a second group received rice bran plus zinc bacitracin, a conventional antibiotic. A third group of chickens received the rice bran diet with a small percentage of either untreated or fermented grape waste.
Also read: Study: Mushroom waste a five-star dish for chickens
Fermented waste performed best
The researchers found that even a small amount of grape waste made a significant difference in the chickens. Compared with chickens fed only rice bran, body weight gain increased by 79%, while average body weight increased by almost 20%, indicating improved gut health.
The fermented grape waste produced the most promising results. The researchers believe this is because the fermentation process changes the chemical composition of the grapes in a way that benefits the gut microbes responsible for improving intestinal health in chickens.
There were also physiological changes in the intestines of the chickens that consumed the grape waste. According to the article in Anthropocene, the benefits of feeding grape waste compared favourably with those obtained from antibiotics.
The researchers do not yet know exactly why grape waste has almost the same effect as antibiotics. They suspect it is linked to the flavonoids, polyphenols and tannins in grape waste – compounds with proven anti-inflammatory and antibacterial properties.
Also read:
From vine to feed: Unlocking the value of grape pomace for sustainable livestock farming in South Africa
A promising wine grape harvest for 2025-26 in South Africa
