We caught up with Sylvia Kehoe, associate professor of dairy science at the University of Wisconsin River Falls, to talk about her work with pre-weaned dairy cattle.
“With young calves we have about an 8% mortality [rate] of those born alive, and about 60% [of those] die because of diarrhea,” she told FeedNavigator. “Sometimes it is environmental or nutritional, but mostly it’s bacterial, so it’s about reducing the amount of bacteria and viruses in the environment.”
Hydration
In addition to her research into gut health, she also has been working with producers to improve understanding of hydration and how that can boost calf health.
“Most people jump straight to antibiotics, but it’s really about hydration,” said Kehoe. “I educate producers on how to rehydrate that calf and how to monitor that calf. If you can catch it [the disease challenge] early on and hydrate the calf really well then you won’t need antibiotics.”
Kehoe said several of the projects she has carried out have been looking at promoting health without the use of sub-therapeutic antibiotics,
One of those recent studies, published in the journal, Professional Animal Scientist, looked at results when 36 young dairy cattle were offered one of three diets – a control milk replacer, that diet along with an antibiotic supplement of neomycin and oxytetracycline, and the control diet but with a series of non-medicated supplements added including dried whey, whey protein concentrate, fat, spray-dried animal plasma, b-glucan, vitamin C and DFM.
The study found no differences between the young cows getting either the medicated diet or the supplemented diet after 35 days, she said. But both groups out-performed the control cattle.
“You don’t need the non-medicated group to be better than the antibiotic group, but they have to be at the same level,” she said. She added that most milk replacers do need some type of supplement.
However, often a combination of additives is used, said Kehoe. “Most of the time you throw in a hodgepodge, probiotics, prebiotics and vitamins – it’s hard to say what’s having an effect,” she added.
Symbiosis effect
Although there has been research looking at many of the supplement types individually, less work has been done to understand how multiple additives may work in combination, she said. And most farms are using a mix of products.
“It would be to everybody’s benefits to see where the symbiosis is,” she said. “If we could start researching the interactions slowly between two products at the most, and really looking at the interactions and the enhancements, that would be [hugely] to our benefit – then we wouldn’t have to hope for the best.”
Some probiotics and vitamins do not give consistent results, she said. “It really depends on the species of the bacteria in the probiotics, it really does depend on the type and the levels of the colony forming units,” she added.
“[And] it depends on the farm,” said Kehoe. “If you have a well-run establishment it can be hard to see the results [from using additives like probiotics], but you also can have a situation where the animals are extremely stressed due to environment and weather and you might not see a result because it’s too much for them to overcome.”
But she said that it may not matter as much to a producer what is happening inside a calf if factors like feed efficiency or weight gain aren’t also improved when a new feed ingredient or supplement is used.
Source: The Professional Animal Scientist
Title: Influence of non-medicated additives as alternatives to antibiotics on calf growth and health
DOI: doi.org/10.15232/pas.2015-01416
Authors: S. Kehoe and D. Carlson