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Arthropods, comprising over 80% of Earth's living organisms and play a vital role to the animal industry. These invertebrates, many of which are ectoparasites, inhabit the bodies of hosts, causing numerous detrimental effects to both animals and humans. Their significance extends beyond their pathogenic effects, as they also function as vectors for major diseases such as Trypanosomosis, Theileriosis, and Blue Tongue in livestock, additionally they transmit various human diseases, including Lyme disease, Tularemia, and Kyasanur Forest Disease. The economic impact caused by the class Arachnida amounts to 46,199.31 million INR, underscoring that the cumulative damage inflicted by the entire phylum Arthropoda can significantly disrupt the livestock industry. Consequently, a comprehensive understanding of this phylum is essential for developing effective control and management strategies. Recognizing their importance, the Veterinary Council of India has established a specialized course, "Arthropods of Veterinary Importance," for veterinary graduates. This book aims to elucidate the key morphological characteristics, life cycles significance, pathogenesis, control, and treatment of major arthropod parasites relevant to veterinary science. It includes detailed line diagrams highlighting essential morphological features for accurate identification. Additionally, the book addresses integrated pest management and acaricide resistance, providing readers with up-to-date strategies for managing arthropods. A dedicated chapter on common laboratory techniques in entomology and acarology will guide readers in preserving arthropod specimens for educational and research purposes. The authors have thoughtfully structured the text into bullet points where necessary, facilitating quick topic recaps.

Entomology is the science, which deals with study of arthropods which parasitize or affect the domesticated animals. Since these arthropods can cause damage or injury to their host by several ways, thorough understanding of the subject is very essential. Most of these arthropods are ectoparasites living on the body of the host or at the most in subcutaneous tissues while very few are endoparasites, living inside the body of the host. Similarly, most of the arthropods are temporary parasites, while very few like lice and mites are permanent parasites. Arthropods comprise of more than 80% of living creatures on earth. Harmful Effects Caused by Arthropods to the Body of the Host 1. Injury to the skin: Most of the arthropods have biting tendency and cause injury to the skin by bites. As a result, micro-wounds are produced on the body which may later on be infected with bacteria leading to localised or generalised pyoderma condition or pyodermatic patches. Similarly, such wounds are predisposed to attack of blow flies which cause a condition called as “Blow fly myiasis.” Animals in order to escape the attack of flies try to run all around leading to phenomenon known as “Entomophobia”. 2. Blood sucking Habits: Most of the arthropods have blood sucking tendency like mosquitoes and ticks which may lead to anaemia. 3. Release toxins: Few of the arthropods release poisonous substances while biting. They inject certain poisons and toxins in the body of host. Eg. Some species of ticks release toxins causing paralysis in host known as tick paralysis. 4. Transmission of diseases: Arthropods have ability to transmit various bacterial, viral, protozoal, helminthic and mycotic pathogens. While sucking blood, they collect infective stages of the organism and while biting to the other host, they transmit the pathogens.

Class: Insecta It is the biggest class in animal kingdom. About 70% of species of animals are included in class insecta. General Morphological Characters 1. All the character of arthropoda are also present in this class. 2. Body is divided into three tagmas i.e. head, thorax and abdomen. Normally body of arthropods consists of twenty segments. Head region is formed by the fusion of 1st six segments. Thorax is formed by next three segments and abdomen formed by last 11 segments. Modification of six pair of appendages of head: 1st pair of appendages is modified into eyes. 2nd pair is modified into antennae. 3rd pair is lost. 4th pair of appendages is modified into mandible. 5th pair modified into first maxillae and 6th pair modified into 2nd maxillae means mouth part is nothing but modification of 4th, 5th and 6th pair of appendages. On abdomen, appendages or legs are lost. Morphology of head region of insects Highest point of head known as “Vertex”. Anterior portion sloping in forward direction known as “Frons”. Posterior portion sloping towards thorax is “Occiput”. On the medial aspect of head, there is a pair of compound eyes. Each compound eye is made of number of lenses called as “facet”. Compound eyes may meet one another in mid line (holoptic) or are wide apart (dichoptic). Just medial to compound eyes, there is a pair of non-functioning simple eyes known as “ocellus.” Just in front of these two eyes on either side, there is a pair of antennae. Antennae are made up of three parts, base, pedicle and f ilaments. Pedicle is non segment basal piece. On these antennae, hair may be present. At the base of each antenna, there is olfactory pin. Lateral part of head is known as “Gena”. Just below the frons, there is a chitinous plate known as “Clypeus”. Below clypeus, there is mouth part. Mouth parts are located on ventral side. Mouth part consists of labrum which forms the upper boundary of mouth and labium which forms the lower lip or lower boundary of mouth. On underneath the labrum, there is membranous structure called epipharynx which bears the organ of taste. On upper surface of labium, there is another membranous structure called hypopharynx which bears the opening of salivary duct. Between labrum and labium there is one pair of mandibles and one pair of maxillae. Mouth parts are collectively known as “Proboscis”.

Characters 1) They are called true flies. 2) It is one of the largest orders in the class Insecta, having more than 1, 20, 000 described species. 3) On thorax, there is only one pair of wing (Di = two; ptera = wings) i.e. Mesothoracic wing. Metathoracic pair of wings are modified into structures called “Halters or balancers.” Halter is a rod like structure having knob at distal end. During flight, this halter goes on vibrating @ 300 vibrations/sec. Its main function is to keep fly balanced during flying/flight. 4) One pair of compound eyes is present which is dichoptic in female and holoptic in male. 5) Larvae are apodous which is called maggots. 6) The order Diptera is divided into suborders, Orthorrhapha and Cyclorrhapha. These sub orders are distinguished morphologically by wing venation and structure of antennae.

Order: Diptera Sub Order: Orthorrhapha Series: Nematocera Family: Ceratopogonidae Genus: Culicoides Species: Culicoides oxystoma, C. imicola  Common name: Biting midges or Biting gnats or punkies or No see-ums. Hosts: Animals and man  Distribution: Worldwide  Morphology of fly 1. Size is 1-3 mm in length. They are the smallest blood sucking flies. They can easily pass through mosquito nets.

Order: Coleoptera (beetles) Class: Insecta Subclass: Pterygota  Division: Endopterygota  Order: Coleoptera Characters 1. They are commonly known as beetles. 2. It is the largest order and contributes 40% of total insects. 3. They bear two pairs of wings of which front pair is fully thickened,hence called as elytra, meet edge in the mid dorsal line act as hard or leathery cover for the posterior pairs of membranous wings. 4. Mouthparts are strongly mandibulated i.e. biting & chewing type. 5. Life cycle shows complete metamorphosis. Pupa is free or exarate type.

Order: Siphonptera (Fleas) Class: Insecta Subclass: Pterygota  Division: Endopterygota Order: Siphonaptera Siphonaptera derived from two greek words viz. siphon (sucking) and apteron (wingless) General characters of fleas 1. Body is laterally compressed. 2. Tegument is highly scleritized. Outer chitinous layer is very thick and it is dark brown in colour. 3. A pair of simple eye or ocelli are present on head. Compound eyes absent.

Lice Class: Insecta Subclass: Pterygota  Division: Exopterygota Order: Mallophaga (Biting louse) and order Siphunculata or Anoplura  (sucking louse) General characters of lice 1. Lice are permanent obligatory ecto-parasites of animals and birds.  2. They are very host and site specific.  3. Lice are dorsoventrally flattened, wingless creatures.  4. Body is divided into head, thorax and abdomen.  5. Eyes are reduced or absent in certain species. Compound eyes are absent. 6. Antennae are short. 

Bugs Class: Insecta Subclass: Pterygota  Division: Exopterygota Order: Hemiptera (Bugs) Characters 1. These are true bugs. 2. Mouth parts adapted for piercing and sucking. Proboscis kept folded in head when not in use. 3. Two pairs of wings usually present, anterior harder pair called hemelytra.Posterior pair is membranous. 4. Both male and female are blood suckers. 5. Metamorphosis is incomplete

Order: Orthoptera This order includes cockroaches and grasshoppers. They bear the following characters: 1. The body is oval and flattened in cockroach and elongated in grasshopper. 2. Two pairs of wings are present. Mesothoracic pair of wings is thickened (Tegmina) and act as cover for membranous metathoracic pair of wings. 3. Antennae are long and multi-jointed. 4. The legs are modified for fast running (cockroach) or jumping (grasshopper). 5. Metamorphosis is incomplete.

Class- Arachnida  •Class Arachnida includes scorpions, spiders, ticks and mites.  •Antennae, wings and compound eyes are absent.  •Body divided into head, thorax and abdomen.  •Mouth is small and adapted for suck blood or tissue fluids of host.  •Most of the members have poison glands or claws for paralyzing the host before sucking.  •The first and second pair of appendages is known as chelicerae and pedipalps, respectively.  •The first six segments of body are termed as prosoma and rest segments as opisthosoma.

 Family: Argasidae  •The family includes fowl ticks and tampans.  •The integument is leather like, frequently mammillated and without dorsal shield.  •Capitulum and mouth parts are situated anteriorly and on ventral side, thus invisible from dorsal side.  •In general eyes are absent, if present these are two pairs and situated on lateral sides of supracoxal folds.  •Spiracles are one pair and situated posteriolaterally to the third coxae.  •Sexual dimorphism is not evident.  •The important genera are Argas, Otobius and Ornithodoros.

Family: Ixodidae (Hard ticks) General characters •These ticks have hard chitinous shield called scutum on their dorsal surface, so they are called hard ticks. Scutum extends over the entire dorsal surface in male and only anterior one-third of dorsal surface in larvae, nymph and female.  •Mouth parts are anterior and visible from dorsal aspect.  •Eyes are one pair (if present) situated on the lateral margin of scutum. •Spiracles are one pair and situated posterolaterally to the fourth coxae.   •Basis capituli or capitulum present at anterior, and have mouthparts and palps. •The body of female may have one pair marginal grooves at lateral side of behind the scutum.

Mites Subclass: Acari Order: Parasitiformes  Suborder: Gamasida/Mesostigmata Characters 1. Mites of this group have the stigmata or spiracles in the middle of the body, hence suborder Gamasida is also called suborder mesostigmata. Mites of this group are referred as gamasid mite. 2. Size of these mites are large about 0.6-2.5 mm in length and hence visible via naked eye. 3. They parasitisize birds and mammals.

Class: Pentastomida General characters 1. Usually, they are considered as aberrant arthropods as some authors suggest it to be related to annelids. 2. They are elongated, tongue like and transversely striated or sometimes, deeply ringed giving beaded appearance especially at the anterior end. 3. Two pairs of strong hooked claws are present at anterior-ventral surface. 4. Eggs contain fully developed larvae when laid

Integrated Pest Management (IPM) is an effective and environmentally friendly step towards pest control based on a combination of common practices. IPM programs use up-to-date and comprehensive information about the life cycle of pests and their interactions with the environment. This information, along with existing pest control methods, is used to control pest damage in the most cost-effective manner and with the least possible risk to people, property and the environment. The IPM methods can be used in agricultural and non agricultural areas, including homes, gardens and workplaces. IPM uses all pest control options, but not limited to the appropriate use of pesticides. In contrast, organic food production shares many of the same concepts as IPM, but limits the use of pesticides to those that come from natural sources rather than synthetic chemicals. IPM is a set of pest management assessments, choices, and actions rather than a single approach of pest control. Growers using integrated pest management (IPM) that recognize the possibility of insect invasion employ a four-tiered strategy including establishing action levels, keep a look out for and recognize pests, its prevention and control. IPM establishes an action threshold—a point at which insect populations or environmental circumstances suggest that pest control intervention is necessary—before implementing any pest control measures. It’s not always necessary to take action when one pest is seen. Future decisions about pest treatment must take into account the degree to which pests will pose an economic risk. Set thresholds through systematic, regular, and consistent monitoring. Develop thresholds that are appropriate for your circumstance. Modifying thresholds, management and monitoring techniques if necessary. For the majority of pest monitoring techniques, quantitative thresholds can be created, such as treating when specific circumstances are favorable for the onset of a disease or when the number or percentage of invertebrate pests or damaged plant parts surpasses predetermined limits. A good monitoring procedure involves knowledge of pest and beneficial species likely to be present, awareness of the critical crop development stages, good sampling and recording techniques and an estimate of infestation level.

Acaricides: Acaricides are agents that kill members of class Arachnida like ticks and mites. Acaricides are used both in medicine and agriculture, although the desired selective toxicity differs between the two fields. What is acaricide resistance? The ability of a parasite strain to survive and/or to multiply despite the administration and absorption of a drug given in doses equal to or higher than those usually recommended but within the limits of tolerance of the subject. How does resistance develop? • Animals are treated with the chemical (Acaricide), exposing nearly all of the tick population to the toxin. • Susceptible individuals are killed, and those rare individuals that have some genetic resistance, survive. • They reproduce, and pass along those “resistance genes” to the general tick population.

1. Collection of arthropods a. Collection of arthropods from the host’s body: The collection of arthropods from the host’s body involves various techniques tailored to different species and circumstances. For instance, the extraction of small ectoparasites such as lice, fleas, and wingless keds typically employs usage of forceps with pointed tips for precision. In poultry, a method of brushing against the grain of feathers enables dislodgement of ectoparasites, which are then collected on a black surface for examination. A highly effective strategy for harvesting ectoparasites from small or deceased hosts, such as poultry, involves sealing the carcasses within a polyethylene bag. This confinement prompts ectoparasites to detach from the host and accumulate within the bag, facilitating subsequent collection using a brush. The retrieval of ticks to prevent the rupture of their mouthparts is achieved by straightening the tick forward and pulling backwards before extraction. These ticks are further placed in a tube sealed with a ventilated stopper or a gauze covered with cotton wool plug. The tubes ought to include paper for the ticks to cling onto, along with a labelled piece of paper. These tubes are stored in a cool and humid container for transportation to the laboratory. This container should be well-insulated and equipped with ice blocks or freezer packs as well as damp pads to sustain elevated humidity levels. It’s crucial to ensure that the ticks do not directly touch the ice. A sizable thermos flask can be utilized for this purpose. Mange mites, on the other hand, are obtained by conducting deep skin scrapings from the periphery of affected lesions, enabling the collection of specimens for analysis.