A PMP EDUCATIONAL UPDATE  |  SEPTEMBER 2018  
DTY Cockroach
 
A letter from the rat
What you need to know to identify this resilient foe

By DR. STUART MITCHELL

My world is dangerous, and I bring my danger into your world. I’m in your sewers. I swim for hours and can enter structures through toilets. I gnaw into your buildings. I’ll get in! I carry fleas, worms, bacteria and viruses to your environment. I evolve 10 times faster than you. I’m smarter than you. I’m the most successful mammal on the planet.

I know you rarely want to see me, but we, the rats, are everywhere!

I’m built for survival. My body is divided into a head and a short broad neck, trunk and tail. I’m covered by a thick pelage, or fur. My tail is covered with flarrable scales.

My head has both a lower and upper lip. My upper lip has a prominent indentation known as the philtrum. I have a pair of long yellow teeth known as incisors. Protruding from my lower jaw is a second set of incisors. Enamel covers only the outer surface of my incisors. The soft dentine of the back of my incisors wears quickly and keeps a very useful sharp edge.

On the top of my head are my external nares, the openings to my ears, which are surrounded by the pinnae. The function of my pinna is to channel sound waves into my ear.

Long whiskers, or vibrissae, extend out from the sides of my head. These are extremely sensitive to touch. My eyes are protected by an upper and lower eyelid. In the corners of my eyes are nictitating membranes (plica semilunaris), which keep my eyes clean.

My body is divided into a thorax and abdomen. A sheet of muscular tissue, or diaphragm, divides my thorax and abdomen. On the bottom of my body is a row of 12 nipples, the external openings to my mammillary glands.

As a female, I have three external openings at the end of my body: the urethral orifice, or opening, to my urinary system; vagina or vulva; and at the base of my tail, the anus, or opening, to my digestive tract.

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In my male partner, two openings are at the base of his tail: the anal opening, which is covered over by the scrotum and contains the testes; these descend only during our reproductive season. The scrotum allows the testes, which are very sensitive to high temperature, to be held outside his body. The cremaster muscles control the ascent and descent of the testes. The urogenital opening is at the penis; it releases sperm and urine from his body.

On my feet are specialized byproducts of my skin, claws, footpads and vestigial thumbs. I walk on my toes with soles elevated; this is called digitgrade locomotion. You walk on your entire foot; this is called plantigrade locomotion. I get into places you can’t.

Now that you know me, do you think you can kill me?


Stuart Mitchell, D.O., DVM, PsyD, BCE, is a board-certified family practitioner and entomologist, and a regular contributor to Pest Management Professional's Direct to You series.

PMP’s Direct To You provides pest management professionals with educational refreshers on timely and critical topics essential to operational success. This content is not be used as a substitute for obtaining legal advice from an attorney licensed to practice where you live. Look for the content-rich PMP Direct To You archives at mypmp.net/direct-to-you-archive.

This newsletter was produced by North Coast Media’s content marketing staff in collaboration with Bell Laboratories.

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