Hymenopthor Ultra granular bait blends a complex range of two proteins, two oils and two sugars, to target a number of pest ant and cockroach species.
Whilst a particular ant species will have a primary food preference, within any colony this primary preference may at times be replaced by a different food requirement. For example, a colony with a primary preference for sugars will at some time change to prefer feeding on oils or proteins. It is well documented in the scientific literature that ants vary their feeding behaviour according to food characteristics, environmental conditions and to the colony’s requirements (after all, they are social insects!).
Recent research has shown this occurs through secretion of the biogenic amine serotonin (5-HT), which is involved in the control and modulation of the colony’s feeding preferences, and presumably regulated by the queen.
Cellular analysis of the ant alimentary canal reveals serotonin immunoreactive processes in the foregut (oesophagus, crop and proventriculus) and the frontal and sub-oesophageal ganglia, suggesting a reason for the taste preference changes observed in feeding worker ants. It is noteworthy that these receptors are at the start of the digestive process and therefore will more strongly influence what the ant chooses to eat. (Serotonin receptors are not present in the mid-gut or hind-gut.) This also means that the ant is consciously aware of required food needs so it will actively seek out the requirements for survival.
Steve Broadbent, regional director for Ensystex explained the impact of this behaviour on bait design. “This behavioural aspect of ant feeding makes it essential to have a bait that can target the colony at all stages through the provision of sugars, oils, and proteins as required. This will then also mean the bait can be used against all species, regardless of their primary food preferences.”
Species like the white-footed house ant (Technomyrmex albipes) and the black ant (Ochetellus glaber) are primarily sugar-feeders, other species such as coastal brown ants (Pheidole megacephala) are primarily oil-feeders and still others, such as the meat ants (Iridomyrmex spp.) and the Pharaoh ant (Monomorium pharaonis), are primarily protein feeders.
“With Hymenopthor Ultra, professionals have one bait that will control all ant species, as well as all cockroach species, both large and small. This is because Hymenopthor Ultra employs Ensystex ‘Advanced bait technology’ to blend together a complex range of two proteins, two oils and two sugars. This targets and eliminates the widest range of ant species, as well as all species of cockroaches, making it the only professional bait registered for all ant and cockroach species. No other company has been able to blend together the range of proteins, sugars and oils required to allow efficacy against all these species. Hymenopthor Ultra is also unique as the actual carrier particles are edible to the ants.”
Mr Broadbent highlighted its broad range of appeal. “In fact, we were exceptionally surprised to see the high success against the Pharaoh ant. Normally this species can only be baited with liver baits, or similarly complete animal protein sources; which is why it is a serious pest in hospitals, often infecting wounds. Initial trials with the Department of Medical Entomology in Thailand however, revealed great success against Pharaoh ant, and this has subsequently been confirmed in further studies in Australia and overseas.”
The performance of Hymenopthor Ultra is further enhanced through the use of Ensystex ‘Liquid oil phase release technology’ – the ‘dry’ granule gives up oil to the liquid feeding foragers.
“Adult ants feed exclusively on liquid foods. They collect these liquids from their prey or while tending Hemiptera and other insects. Solid prey, that which is most often seen being carried by workers, is generally intended as food for larvae. Thus most baits are only targeting these larval stages that can feed on solids.
“Adults that remain in the nest, including the queen, receive much or all of their food directly from returning foragers in a process called trophallaxis. During foraging, workers collect fluids that are then stored in the upper part of their digestive system. Upon returning to the nest, these workers regurgitate a portion of this stored fluid and pass it on to other workers. With ‘Liquid oil phase release technology’ we can therefore target the worker ants directly even with a granular bait.
“Ants are very resilient and many aspects of their biology work against their control. Foremost, worker ants place a greater value on their reproductives (queens) than they place on themselves. Therefore food is only passed to the queen after passing through several workers. If any workers suffer ill effects from a food source, they will compartmentalise themselves from the food chain thus ensuring the queen is not harmed.
“Secondly, worker ants are expendable – and their demise is of no great consequence to the future of the colony. Thus any control option that only reduces the number of workers will never be effective at eradicating the ant colony. This means that the effects of any bait need to be delayed to allow for the workers to return to the colony and feed it through to the queen.
“In Hymenopthor Ultra this is achieved by using a low level of fipronil, which is dissolved into the oils; this blend is then added in a manner to coat the granules. This is not a simple process as the granules are not a uniform size and have irregular shapes. This is deliberate as our trials showed that irregular shaped particles were preferred by the ants, presumably as they are easier to carry. And a range of sizes ensures we target all species, though even small species such as Pheidole megacephala will team up to take even the largest particles back to the nest, such is the palatability of the bait.”
Mr Broadbent pointed out that, “With such a unique bait we considered its application against other insect species. Various published scientific studies show cockroaches have an exceptionally high preference for solid based foods, with bread ranking higher than most cockroach gels as a preferred food. Trials with cockroaches showed they readily and aggressively fed on the cereal base used in Hymenopthor Ultra with results and speed of kill better than those achieved with gel cockroach baits.
“The ‘Liquid oil phase release’ ensures the fipronil is readily digested by the cockroaches and Hymenopthor Ultra satisfies their preference for a solid cereal based diet. Results were particularly good when targeting the larger Periplaneta cockroach species, especially the nymphal stages, the most difficult life-stage to control.
“Consequently, Hymenopthor Ultra is opening up new opportunities for professional pest managers when dealing with both of these troublesome pest species,” concluded Mr Broadbent.