Different types of rodent. Enjoy!

Vector and Pest Management: Rodents.

Characterized by single pair of incisor teeth on each jaw and by absence of canine teeth.Have tail with fine scales and few hairs.

PROBLEMS?

• Spread serious disease such as salmonellosis which is food poisoning, leptospirosis, ricketsialpox and etc.
• Carry fleas, which is potentially spread disease such as bubonic plague.
• Consume and contaminate about 20 percent of the world's food supply.
• Gnaw, expensive structural damage, start fires if they gnaw on electrical wires.
• Cause a great deal of anxiety for occupants of infested building.
• Pose serious risks for food facilities.

RODENTS IN MALAYSIA.

Species of rodents we deal most are:-

• Roof rats (Rattus Rattus)

Sometimes called as black rats 

Appearance: 16-24cm in lenght, with a tail longer than head and bodies. 150-200g in weight and pointed nose, large ears, slender body when compared to the Norway rat.

Life cycle: 5-10 young per litter, 3-6 litter a year. Gestation period about 3 weeks and 12-16 weeks from birth to sexual maturity.

Habits: Rarely in Malaysia. Can climbs, agile and rarely burrowing and outdoor in Malaysia. Preferred food is moist fruits. Will eat around 15g of food and drink 15ml.

• Norway rats (Rattus norvagicus)

Sometimes called as brown or sewer rats. Usually found along building foundations, beneath rubbish or woodpiles and in moist area in garden or fields. May be lined with shredded paper, cloth or other fibrous material.

Their appearance is up to 40 cm in lenght, tail shorter than the head and body. Their weight is 350-500g and they has blunt nose, small ears and a thicker body when compared to the Roof Rat.

Lifecycle: 7-8 young per liter, 3-6 litter a year. Gestation period about 3 weeks and 10-12 weeks from birth to sexual maturity.

Habits, usually ground living and burrowing, but sometimes climbs. The only species to occur in sewers in Malaysia. Preferred food is cereal and will eat around 30g of food a day and drink 60ml.

• House Mice (Mus Musculus)

Called as domestic house mouse which is live and thrive under a variety of condition in and around homes or farms. In addition, contaminate food preparation surface with their feces, which can contain the bacterium that causes food poisoning such as Salmonellosis.

Appearance: 7-9.5 cm in lenght, with a tail around the same lenght. 12-30 g in weight and has small feet & head and large eyes & ears.

Life Cycle: 4-16 young per litter, 7-8 litter a year. Gestation period of about 3 weeks. 8-12 weeks from birth to sexual maturity.

Habits: Usually ground living and burrowing but often climbs. Preferred food is cereals. Will eat 3g of food a day and can survive without any additional water and they will drink up to 3 ml a day if their diet is particularly dry.

COMMENSAL RODENTS.

• Members of Rodentia, Family Muridae.
• They destroy property, frighten people & compete with human for food.
• These rodents are "commensal" because they tend to live in close proximity to humans and eat the same food as we do.
• Rats plague many store owners and farmers.
• undesirable in feed and seed stores because destroy the seed, corn and etc.
• Destroy & contaminate structure as well as harm young birds and chicks.

DID YOU KNOW?

• In some areas of the world, rats destroy as much as one-third of entire harvest.
• Rats gnaw and burrows, they can cause structural damage of buildings.
• Also gnaw insulation off wiring which has started fired in building.

BIONOMIC FACTORS OF RATS.

SENSORY ORGAN 

• long mustache and other fine hairs on their body.
• sensitive hair helps them.

SMELLING ORGAN

• Very sharp.
• When active, they shake their head and smell.
• Leave special odour as movement guide such as urine and genital fluid.

HEARING.

• Detect sound up to 100kHz
• House rats-90kHz.
• Afraid of high level noise.

VISION.

• Useful for night vision.
• High sensitively of light.
• Can see as far as 15m distance.

TASTE.

• Very good tasting organ.
• Ability to different between a plain bate and a poisonous bate.

PHYSICAL ABILITIES.

• A good swimmer and diver.
• It can swim up to 1.4km/h.
• It can climb anywhere.
• Can fall from 15feet without any injury.
• Good balancing.

SIGNS OF RATS PRESENCE.

• Feces.
• Footprints.
• Runway.
• Smears.
• Bitemarks.
• Burrows.
• Smell.
• Urine.
• Live rat.
• Carcass.
• Nest.

WHAT IS PUBLIC HEALTH ISSUES FOR RATS?

- Rats play an important role as host for certain infectious disease and its can spread directly or indirectly.

• Directly: Rat carry germs inside their body. Organism eg: bacilli, nematodes, viruses and etc.
• Indirectly: Rats being host for fleas, mites and etc.

RODENTS AND HUMAN HEALTH.

Disease related to rodents such as.

1. Hantavirus Pulmonary syndrome.
2. Haemorrhagic Fever.
3. Leptospirosis.
4. Human Lymphocytic Choriomeningitis.
5. Plague.
6. Rat-Bite Fever.
7. salmonellosis.
8. Murine Typhus.

RODENTS CONTROL MEASURES.

• Eliminating sources of food.
• Eliminating breeding and nesting places.
• Rat-proofing buildings and other structures.
• Killing them.