The Probiotics completed a pilot study for the effects of probiotics on foraging behaviour and we learned a lot! We have some slight alterations to complete before the weather warms up in September and we can have a better go at completing this assay.

The Probiotics team have been busy - we have commenced our behavioural experiment to see if the probiotics have an effect on pollination and foraging behaviours. We will apply the treatments to the larvae cells, individually tag the adults once they emerge and then film them in a large flight cage over 3 weeks to see if the treatments change the way bees forage for food. This experiment will span 9 weeks and finish towards the end of May 2025!

We're testing our probiotics on hand-reared larvae, grafted from our campus hives. Here are some week-old larvae preparing to pupate: they've been hand-fed and inoculated with some 'Native' probiotic mix so we can assess how the probiotics might affect their maturation into adulthood.

The Probiotics team have been busy perfecting the trial protocol. It starts with caging the Queen honeybee in a special frame cage, so that we can be sure of the age of the brood laid whilst she's inside. The workers can fit through the cage bars, but the queen cannot move through to the other frames inside the hive.

It's ok, we did it on purpose!

Last week the Probiotics Team started an infection assay to make sure we could inoculate the reared larvae with controlled amounts of the common honeybee diseases. One of them is Chalkbrood, a fungal pathogen that invades the guts of larvae and mummifies them from the inside out. It is next to impossible to fully get rid of chalkbrood from your honeybee hive because the spores can live for years preserved in the hive environments.

Here we have two larvae, close to pupation, covered in fungal growth.

We're aiming to create a probiotic mix that will help the larvae fight this fungus within the gut so the individual bee doesn't succumb to this disease.

The Probiotics Team started a pilot study in March 2024 to understand how we might inoculate bee larvae with pathogens that don't kill them off straight away - this is a complex method where we graft tiny bee larvae, just one day old after hatching from eggs, and place them into sterile containers in which to raise them to adulthood. We feed them a mix of royal jelly, yeast, fructose and glucose each day to they grow to pupation, and along the way gave them a micro-dose of one of three common brood diseases to understand how to infect them for future probiotic treatment experiments.

Did you know we have an apiary of hives at Macquarie University?

Having colonies on campus means we can have access to bees for all sorts of research, including understanding pollination behaviour, how temperature effects the colony and other ecological questions. In this photo, several adult bees are taking a drink of their stores, but we can also see some uncapped cells in the bottom left corner with tiny eggs inside, next to some capped cells that contain pupae that are developing into adults! The top of the photo shows capped cells full of honey, and in the middle is some cells with collected yellow pollen.

Watching bees go about their business and organise their living spaces is such a privilege to witness!

The Probiotics Team headed to the NSWAA conference in May 2023, and boy, did we learn a lot about Varroa mites! It was wonderful to meet so many apiarists, industry, government and researchers working with bees in Australia, as well as the plenary speaker, Prof. Samuel Ramsey from the USA, who gave two great talks on both Varroa and Tropilaelaps mites.

The Probiotics Team attended the annual Sydney Bee Day which was hosted by the University of Sydney this year. This meeting allows researchers working on bees in NSW to come together and introduce themselves and their work - USyd put on a fantastic day and fed us all very well. Fleur, Theo, Darsh and Vanessa each presented a brief insight into what we've been up to lately.

We invited the diagnostic team from the DPI EMAI Biosecurity branch to come and visit the lab facilities and have a chat over morning tea this month. It was a great opportunity to network with Mark Westman, Belinda O'Rourke and Khushbu Ghandi, who work with honey and bee pathogens directly from Australian Apiarists. We hope that connections such as these lead to exciting future collaborations.