17 April 2023

What do cockroaches eat?

By Killian

What do cockroaches eat?

The term cockroach corresponds to a varied group of insects belonging to the Blattodea order, which are also grouped into three superfamilies, within which there are different families and, therefore, a diversity of species. Some of the more well-known types of cockroaches are giant, wood, American, and brown-hooded. Certain species have a restricted distribution, but others, such as the American cockroach (american periplanet), native to Africa, are found all over the world, even being considered a pest in certain regions.

Some of these insects are very common in urban areas, since they have associated with humans, particularly because they have found a fairly abundant environment to feed on. So, if you’ve ever wondered what these animals eat, keep reading this AnimalWised article and find out what do cockroaches eat.

Type of diet of cockroaches

In general, cockroaches They tend to have an omnivorous diet.. In fact, their diet is very varied, but, depending on the species and the habitat where they develop, some may have a predilection for certain foods, so we can also find that certain types of cockroaches have a diet based on vegetable matter, fungi and detritus.

Although cockroaches have a preference for a diet based on organic foods, they can also eat processed products that are commonly used in households.

cockroach digestive system

The digestive system of cockroaches, in general, corresponds to that of insects. In this sense, we can distinguish three parts. The first is known as part former and includes the mouth, made up of chewing-type mouthparts, which have the mechanical function of processing food and then mixing with saliva, which fulfills a chemical function in their processing. In the anterior part we also find the pharynx, the crop and the esophagus. Then we have the part half, which is made up of the stomach and intestine. Here it is worth mentioning that cockroaches eat plant materials made of cellulose, which they cannot digest on their own and, therefore, they rely on a symbiotic relationship with microorganisms that digest this type of material. Finally, there is the region laterlocated towards the end of the abdomen and where the rectum and anus are.

Some species that feed mainly on wood, such as the Australian wood cockroach (Panesthia cribrata), degrade cellulose from specific digestive enzymes produced by the animal.

On the other hand, in relation to the symbiotic bacteria that a large part of the species of cockroaches have, it is important to mention that, at birth, they do not have these symbionts to degrade the cellulose present in plant matter. To acquire these microorganisms, a transfer mechanism known as “proctodeal trophallaxis” occurs, so that the parents transfer them from their anuses to the mouth of the small newborn nymphs. Trophalaxis is common in other types of insects, which can also occur from mouth to mouth.

What do cockroach nymphs eat?

The life cycle of cockroaches includes three stages, which are: egg, nymph, and adult. These insects have a type of development known as hemimetabolous, which means that their metamorphosis is not complete, so that nymphs emerge from the eggs very similar to the adults, but without wings and in some cases with different colors.

So what do small cockroaches eat? When the nymphs emerge from the egg, it is common for the first food let them eat what’s left of the ootheca, which is the structure produced by the female to deposit and protect the eggs while they develop. Then, the nymphs begin to feed on practically the same as the adults, depending on the food available in the place where they are. During this stage, cockroaches can move on their own and take food on their own, but it is common for the parents to provide food at first.

What do adult cockroaches eat?

As we have mentioned, cockroaches are animals that have a very broad diet and this can be somewhat more specific depending on the species or the habitat where the animal develops. In this way, since there are different species that have been commonly associated with people in urbanized sites, they consume a variety of foods that are present in cities.

In this sense, below, we mention a list of foods that adult cockroaches eat:

  • Starch
  • sugars
  • Milk
  • Cheese
  • meats
  • Grain
  • Sweets
  • Bread
  • Eggs
  • Fungus
  • debris
  • Wood
  • Faeces
  • Blood
  • Fur
  • Nails
  • Cortex
  • Starch
  • Paper
  • Wool
  • Soap
  • Leather
  • animal remains
  • other cockroaches

Given the above, if you wonder what house cockroaches eat, you can already see that they can feed on practically everything in your home, especially what is in the kitchen, which is why this is one of their favorite places.

It is common for cockroaches to carry different pathogens on their legs and mouths that cause diseases in people and pets because they move through an infinite number of places, including spaces with microorganisms present in feces remains, contaminated food, and animals in decomposition. Then, these insects enter homes loaded with these pathogens such as bacteria, fungi, viruses, and helminths, so that they finally end up in people’s common spaces where food, water, and objects for personal use are found. In this way, it is important to maintain adequate hygiene and cockroach control measures. In this other article we explain how to drive away cockroaches without harming them.

What do cockroaches eat?  - What do adult cockroaches eat?

If you want to read more articles similar to What do cockroaches eat?we recommend that you enter our section on balanced diets.


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