August 6, 2018
Injectable trace minerals boost cow's ability to combat aflatoxin related problems
An adequate amount of trace minerals can help a dairy cow's liver better deal with aflatoxin, which can impact animal performance, appetite, milk productivity and immunity, according to the lead author of a study conducted by researchers at the University of Illinois.
"If we are providing enough trace minerals to manufacture more detoxifying enzymes, the liver has a better chance of fighting the aflatoxin," Russell Pate of the Department of Animal Sciences said. Pate's research focused on the role of injectable trace minerals in mitigating aflatoxin-linked damages and keeping cows healthier.
An injectable product could potentially benefit a cow when its appetite is affected by aflatoxin related issue, Phil Cardoso, assistant professor in the department and co-author on the paper, commented.
"Our idea for injecting is that it might help during a time when [a cow's] intake is impacted. If something is causing her to eat less, she'll consume less of any diet-based mineral too," Cardoso explained.
As part of the study, the researchers administered lactating Holsteins with Multimin®90, a commercially available injectable trace mineral formulation. This was done twice, about a month apart.
Another set of animals received a saline injection only, but both sets received the recommended amount of trace minerals in their diet.
About a month after the second injection, the researchers used a balling gun to introduce aflatoxin-contaminated feed to half of the animals.
Cows receiving aflatoxin and saline had greater liver inflammation and lower feed efficiencies than cows which weren't exposed to aflatoxin.
However, introducing Multimin®90 to aflatoxin-challenged cows increased liver concentrations of selenium and iron. It also induced the activity of serum glutathione peroxidase, whose role is to protect cells from oxidative damage by neutralising free-radicals.
"As we had hypothesised, supplying cows with trace minerals via injection, independent of minerals ingested in the feed, resulted in an improved immune response and reduced oxidative stress when cows were challenged with aflatoxin," Pate said. Trace minerals are co-factors of enzymes responsible for alleviating the oxidative stress in animals.
Aflatoxin M1 was present in all milk samples for cows which received the contaminated feed. In other words, injectable trace minerals did not prevent transfer of the toxin into the milk.
"We knew it would not help with transference to the milk. If the cow is exposed, she needs to excrete that toxin through milk, urine, feces," Cardoso explained. "To stop transference to the milk, you have to first identify the source of the aflatoxin and avoid feeding it. But sometimes, you just can't. In those cases, we are showing for the first time that an injectable trace mineral will provide a benefit."
The article, "Injectable trace minerals (selenium, copper, zinc, and manganese) alleviates inflammation and oxidative stress during an aflatoxin challenge in lactating multiparous Holstein cows," is published in the Journal of Dairy Science.
- University of Illinois at Urbana-Champaign / Phys.org