The larvae can also externally digest solid food brought back by adult ants. The larvae produce soluble proteins which are in turn sought from them by the adult ants. The larvae regurgitate the digested solid food back to the workers in a liquid form. This has led to the concept that ant larvae might also serve as a specialised digestive caste.
Recent studies to determine whether bait digestion by larvae is a key factor in the consumption and distribution of the toxicants from baits to worker ants, have shown interesting results. Understanding the mechanism that allows a bait toxicant to enter the colony is fundamental for effective control and enables us to develop baits that better target colony elimination.
What has been discovered is that more important than the provision of solid-phase or liquid-phase food to the larvae, is the fact that toxic baits are most effective by their action through the mouth parts, where food enters the cibarium, the space anterior of (in front of) the true mouth cavity. This chamber opens into a second chamber, the infrabuccal pocket, that is a collection site for solid food particles.
Whereas liquid food is directly imbibed by ants from the surface of their labium (tongue), and carried into the pharynx, through the oesophagus, and into the crop; particles of solid food, obtained by licking with the labium, or rasped off by the maxillae, are carried into the infrabuccal pocket where they are moulded into a nutritious pellet.
Ants also use their labium to cleanse one another and their brood, by which means many food particles may be carried more directly into the infrabuccal pocket. The solid portions, when no longer of any nutritive value, are cast out as a small pellet of refuse. This use of the labium for cleaning, can also spread the toxicant through the ants exoskeleton.
Ducts from the propharyngeal, postpharyngeal, maxillary, labial, and mandibular glands enter into the cibarium and infrabuccal pocket. It appears that baits stored in the infrabuccal pocket come into contact with these various glandular secretions and, if formulated to target this process, release their toxicant into a liquid form. Through trophallaxis among workers, the toxicant then spreads rapidly through the colony, without the need for digestion by larvae. Thus, the larvae are not critically important for the transmission of the toxicant in the colony.
Hymenopthor Ultra Granular Ant Bait was carefully formulated to target this feeding biology and provide the most effective means of colony control. Fipronil was chosen as the active, since it is non-repellent, readily transferred from one ant to the next and, due to Ensystex’s Liquid Oil Phase Release Technology™, it is released into the above glandular secretions and spread through the colony by direct worker to worker trophallaxis.
Traditionally, a difficulty with baiting for ants has been the wide range of feeding preferences of the different species (See Table 1). This is further complicated by the fact that the colony’s feeding preferences change during different seasons.
Hymenopthor Ultra was specifically developed to overcome this by employing a complex blend of sugars, animal proteins, and oils to ensure optimal palatability for all species of ants (and cockroaches). It works as both a liquid and a granular bait to optimally exploit the ants social/ feeding structure as discussed above.
Uniquely, Hymenopthor Ultra uses an edible cereal base as the carrier. Most granular baits use inedible grits as the base. This is why Hymenopthor Ultra works more effectively, as the actual cereal base is consumed and distributed through the colony through the infrabuccal pocket.
Hymenopthor Ultra effectively provides a better control solution than liquid or gel baits. It can be used indoors or outside, and it can be placed deep into cracks and harbourages, along ant trails, or if required, inside reusable Hymenopthor Ant Bait Stations. These Stations are cleverly designed to provide access to insects of different sizes and prevent bait spillage.
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