Scope and Branches of Medical Zoology : • Biology (Gr. "bios" = life+ "logos" = study) is the branch of science which investigates the origin, structure, functions and distribution of life in all its forms. • Biology is the combination of Botany and Zoology, therefore it is nothing but study of living things. • Botany deals with the study of plants. • Zoology (Gr. "Zoion" = animal + "logos" = study) is the branch of life sciences that deals with the study of animals • This world contains a great number of animals living in diverse habitats. • They exhibit a great diversity and variations. • These large number of known species are classified in various phyla of Animal Kingdom. •There are large number of animals which are free living and some are leading life with symbiotic association with other animals. • These animal associations may be beneficial like; commensalism, mutualism or they may be harmful like parasitism. •In parasitism one organism lives on or in another organism using its nourishment. •These animals influence man's welfare in harmful ways. •Parasites injure man and his domestic animals. •Many animals carry disease (vectors) and others themselves are disease agents such as those causing malaria, filariasis. •Destruction of crops and fruits by insect pests is a problem for agriculture. •Thus in Zoology, there are variety of organisms which are economically important and hence economic Zoology is the special branch in which one can Study the useful and harmful animals for man kind. •Thus, Parasitology is the branch of Zoology which deals with the study of parasitic animals. •There are large number of parasitic animals in some phyla like Protozoa, Platyhelminthes, Nematoda and Arthropoda which are harmful to man and cause various diseases or may kil human population. •Hence, these parasitic animals are medically important and separate branch called Medical Zoology is evolved. Medical Zoology : Medical Zoology is the branch of medical science which deals with parasite found inman, their morphology, life cycle along with their pathogenic effects. Sometimes it is treated as a branch of Microbiology. It deals with harmful bacteria, viruses and protozoans. Under medical zoology, the animal parasite , which medical men have to deal with are divided into four main group: 1. Medical protozoology 2. Medical Helminthology 3. Medical Entomology 4. Forensic Entomology •There have many animals that are beneficial to man and on the other hand many of them are quite harmful to man. •The harmful animals affect the Humane Society in various ways. •Some of them are used to damage the food crops and food, some of them are destroying the domestic animals and even the parasite in animals and as a result causing diseases to man. • Medical zoology deals with the scientific study of such animals. •In the human body the parasitic animals get entry either move the drinking water and food or sometimes directly to the body and as a result the human beings the human beings suffer from some disease. Medical protozoology : It is the branch of science which deals with the study of protozoal parasites which consist of a single cell like unit which is morphologically and functionally comple • All classes of protozoa have disease producing members, but they are more in Flagellata and Sporozoa. • Human beings alone have over 15 species of parasitic protozoa. • The various diseases caused by protozoans in human being are; Amoebiasis, Diarrhoea, Trypanosomiasis, Leishmaniasis, Trichomoniasis, Malaria, Toxoplasmosis, Balantidial dysentery. • Therefore, medical protozoology is very important branch and every Zoology student should study it. 2. Medical Helminthology: •It is the branch of medical science which deals with the study of helminth parasites of medical importance to human beings. •Helminth parasites are divided into two groups which are: Platyhelminthes and Nemathelminthes. • Platyhelminthes are flatworms which include various cestod worms like; Taenia and trematods like liver flukes. •Nemathelminthes consist of round worms like; Ascaris, Filaria, Trichinella, Guinea worms. •All the helminthes are endoparasites of gut and blood in the human body and cause various diseases collectively called helminthiasis. •The diseases caused by the nematode worms constitute nematodiasis. The most common human diseases caused due to infestation with the nematodes. Medical Entomology: •It is the branch of science which deals with the study of harmful insects to man and his domestic animals, their morphology, life cycle and pathogenic effects or diseases caused by them. • Insects are constantly attacking man and his domestic animals by spreading various kinds of diseases in them. •They destroy his property and his crops. Hence, study of insects is of very great importance to man. •Insects impart diseases in two ways: (i) They bring harmful effects by destroying tissues of their hosts and (ii) Some insects transmit disease producing bacteria and protozoans. •Many insects act as a vector which carry disease causing organisms from one host to another. •Houseflies, flies, mosquitoes, bugs, fleas, lice, etc. act as a vector. •Several species of mosquitoes are vectors of human malaria. • Female Anopheles transmits malarial parasite to human beings. • Culex mosquitoes act as intermediate host and vector of the larvae of a nematode filaría. •Aedes aegypti is the vector of virus of yellow fever. •Flies like houseflies transmit germs of typhoid, cholera, dysentery and diarrhoea. •Glossing or Tse tse fly is the vector of Trypanosoma from animals to man causing disease African sleeping sickness. •Phleotomus, Tabanus, Chrysops etc. •flies are biting and blood sucking, causing kala azar, oriental sores, calabar swellings. 4. Forensic Entomology : • It is the recent branch of applied entomology in which thestudy of insect and other arthropods found in and on human bodies suspected of criminal action helps in the investigation and initiation of civil proceedings. • From forensic entomology, one can only know the time, approximate or nearer the occurrence of crime (murder), which of course can go a long way in solving the mystery of the crime. • The insects provide the information because they consistently feed or breed on or inside the corpse. • Do so more accurately, because of their precisely timed developmental stages, eggs, larvae, pupae and adults. • Thus, throughout the time of investigation, the stages of insects on the dead body can give clue to the time since death'. • There are number of arthropods which may appear in postmortem which include Dipteran flies like, winter gnat, blow fly, screw worm, flesh fly; coleopterans (bettles), Lepidoptera (moths), Hymenoptera (ants and wasps) and even cockroaches. •These animals can give many forensically important facts like; when did the death take place (time since death)?, environmental condition in which the death occured, possible cause of death in suspected cases of suicides, etc.
