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Mylo®’s effect on the live weight of calves.


Independent research by the University of Queensland.

The long-term productivity benefits of improving health and growth of calves in their early stages of development is well documented and understood.

The Good Clinical Practice Research Centre at the University of Queensland’s School Veterinary Science conducted a double blinded, controlled, randomised study to evaluate the efficacy of Mylo® on the live weight of pre-weaned dairy calves.

Study Design and Methods:

Forty-four clinically healthy calves of approximately 3 days of age were randomly split into two equal sized groups – Test Group (22 calves) and Control Group (22 calves). Calves were housed in individual pens as part of a controlled study design to reduce the risk of cross contamination with commonly occurring health ailments.

All animals were tube-fed colostrum before reaching approximately one day of age. The feeding regime for all animals consisted of milk replacer at 15% of their body weight, fed in a bucket twice a day, plus ad lib access to hay, grain pellets, and clean water through the entire period of the Study. With exception to Monensin, there were no feed additives or antibiotics added to the feed. Mylo® was added to the milk replacer of the Treated Group.

Assessments were conducted fortnightly through the study which concluded when calves reached 56 days of age, consistent with the weaning age at this university dairy operation. At the end of the study, tissue and organ samples were taken from three calves in each Group after weaning, for measuring weights of their key gastrointestinal organs.


Calves in the Test Group were 8.4% heavier, and uniformity of liveweights was better, at weaning age compared with calves in the Control Group (p=0.02).

Average and total feed intake did not differ between the groups.

The initial histological examination of the organ tissue of the gastrointestinal tract indicates the treated animals exhibit accelerated development of gut structures. There was an observed increase in the surface area of the lining of the gut.


Calves in the Test Group were heavier at weaning (56 days) and had heavier gastrointestinal tract organs compared with calves from the Control Group, while average and total feed intake did not differ between the groups. These observations warrant further study into the impact of Mylo® on gastrointestinal tract development. Morphological examination - comparing the form, shape and size - of the organs is expected to be reported on later.