Alok Kumar Singh¹, Shailendra Singh², Deepali Tiwari³, Ravi Kumar Khare¹ and Baleshwari Dixit⁴

¹Department of Veterinary Parasitology, College of Veterinary Science & A.H., Rewa

²Department of Veterinary Pathology, College of Veterinary Science, & A.H., Rewa

³B.V.Sc & A.H., Student, College of Veterinary Science & A.H., Rewa

⁴Department of Veterinary Public Health & Epidemiology, College of Veterinary Science & A.H., Rewa

^#corresponding author- email: alok122@gmail.com

Introduction

Arthropods are generally external parasite which feeds on body tissues such as blood, skin and hairs of the host. External parasite causes wound and skin irritation which cause discomfort in   animal and secondary infection. Heavy infestation causes blood loss i.e. anaemia, weight loss, reduced milk production and nervousness in animal. External parasite can transmit disease from sick to healthy animal in herd. It causes huge economic loss through skin damage and affect rendering process making it unsuitable for leather                  industry.

Major External parasites

(i)  Lice

• Lice are external parasite which spends its entire lifetime in host. Both mature and immature stages are feed on host.
  • Lice infested animal have dull and depressed, matted coat. Usually sucking lice pierce skin and draws blood while biting lice has chewing mouth part which feed on hair, scab exudation.
  • Louse population varies seasonally depending on condition of host, also reaches maximum during late winter or early spring. And get minimal during summer.
  • Animal during stress generally support more numbers of louse.
  • Transmission between animals takes by direct contact. Usually in herd or by different animals from different farm when introduce to new population.
  • Saliva and faeces of lice contain allergic substance which causes skin irritation. Severe pruritus, thriftiness, dull tuft of fleece of sheep is noticed.
  • Population of lice varies seasonally depending on condition of host. Lice population is greater during rainy season.
  • Louse control is difficult since pesticide is unable to kill its egg. The best control of lice is by animal residual spray and retreatment is done generally   after 2 week of primary application.
• Biting lice
  • Biting lice generally more prevalent in winter time in goats causing severe   losses.
  • Biting lice feeds on skin debris, on scales, bits of hair of goat and sheep. Life cycle completes in 1 month and eggs usually hatch in 9-12 days.
  • Bovicola limbata and holokartikos crassipes are two major biting lice species.

(b) Sucking lice

Predominant species of sucking lice in goats are:

1. African body louse-generally found in semi tropical climates in India, US. Louse generally found in body, neck, head of goat.
2. Foot louse – generally found in feet of sheep and goat during heavy infestation ii..e. in spring lice may affect belly region. In bucks scrotum region is severely affect. Lambs   are more affected than adults. This louse species eggs take more time to hatch than other   therefore treatment is preferred after 3 weeks of infection.
3. Goat sucking lice – found all over body of sheep and goat.
4. Face and body louse and long nosed cattle louse are minor pest of goat.
5. Nose bot fly. Nose bot fly infects nostril of sheep and goats. Larvae are laid in nostrils from where it migrate to nasal passage and feeds on mucous and mucous membrane. It can cause eye damage in humans. Symptoms are shaking of head, loss of appetite, and discharge from           nostrils. In presence of flies in nasal tract animal get excited, snort and rush its nose in dust and shake its head which causes uneasiness in sheep.
6. Keds
7. Keds also known as louse flies which are large, flattened, wingless parasite flies.
8. Keds biting causes irritation which lead to rolling of animal on   ground to relieve irritation.
9. Ked usually don’t cause much damage if animal is fed on nutritional     diet and it is more prevalent in winters.
10. Eggs are retaining in female ked body and develop to larvae and pupate which get stick to the hairs of animal. Female ked develops one larva at a time.
11. In total lifespan of 100-120 days female ked produces 10-15 young   ones and gives birth in every 8-9 days. Pupal stage generally last for 18-30 days.
12. Mites
13. Itch or mange mites (psoroptes , sarcoptes ) feeds on skin or burrow deep in skin making tunnels from .1 to 1 inch in depth.
14. Fluid discharge at opening of burrow lead to nodule formation       also toxins is released by mites who cause irritation and itching.
15. Infected animal scratch and rub continuously to relief irritation. Infestation is       contagious to the animal in herd hence control is required.
16.  Most common mange of goat is psoroptic ear mite (psoroptes  caniculi )which lives in auditory canal and temporarily on body .
17. Mites are microscopic cannot be seen by naked eyes. Life cycle is similar to ticks containing egg, larvae, nymph, and adult stages. Lifecycle may complete in 1 month and female laid 16 eggs in a lifetime.
18. Demodectic mange – which invade hair follicle and sweat gland of animal.
19. It causes thick scab over skin and leads to nodule and pustule formation over skin.
20. For control dipping is more effective than spraying some common acaricide are Diazinon 60% and ivermectin (200mg/kg) is effective treatment.

(iv)   Stick tight flea

• Flea are small, wingless, dorsoventrally flatten, posterior legs are well developed and can jump upto 7-8 inches.
• Under favourable conditions female flea attaches to face and   ears of  host and during this time eggs are laid which further drops to ground and develops into larvae. Generally development takes place in bedding material of host.
• Larvae are small worm like legless insects with chewing            mouth parts which feed on organic debris.
• Larvae develops into pupal stage which give rise to newly developed flea which feed on blood within 24 hr. causing impact on host.

• Tick
• Ticks are the most common ectoparasite which causes economic losses. Ticks may be divided into soft tick (Argasids) and hard tick (ixodids). Hard ticks can be further divided into one, two, three host tick based on number of host involved in lifecycle.
• Ticks common effects on host  are reduced growth, milk production, damaged hide and skin, transmission of various tick borne diseases in herds
• Also predispose to other secondary infection of screw worm flies and infection by pathogen Dermatophilus congolensis.
• Some common tick borne diseases common in sheep and goat and it’s causative agent are as follows :
• Babesia ovis: transmitted by Rhipicepalus bursa and Rhipicepalus evertsi; Babesia motasi transmitted by Haemophysalis spp, Dermacentor spp, and Rhipicepalus bursa; Theileria ovis: transmitted by Rhipicepalus bursa and Rhipicepalus evertsi:
• Anaplasma ovis: transmitted by Rhipicepalus bursa and Rhipicepalus evertsi;
• Heart water: transmitted by Ambylomma herbarium and Ambylomma variegatum
• Tick paralysis: transmitted by Ixodes rubicundus. Rhipicepalus evertsi, Ambyloma and Dermacentor.
• Acaricides are most common method of tick control.

Prevention of external parasite

• Conduct regular physical examination of sheep and goat once in a  week . Check for flaky skin, hair loss, crusty skin or bumpy region for parasite infestation.
• Separate and isolate infected animal showing infestation of parasite from herd to prevent spread of parasite to other animals.
• Practice good sanitation practices that are to clean animal barn properly, removing bedding material regularly.
• Seal cracks and crevices with mud or cements in animal    shed and regularly clean litter.
• Reduce parasitic load on pasture by rotating animals grazing land which provide minimal exposure to parasite.

Treatment and control of parasite

• Use of suitable pesticides for effective killing by dipping,        spraying on animal to reduce infestation.
• Once the animal are treated with acaricides clean building and bedding with chemical but it overuse can cause development of resistant in external parasite.
• Effect and incidence of ectoparasite can be reduced by   improving nutrition which improves overall health and immune system of animal also, hygiene of animal and houses should be managed.
• Do not recommend unnecessary ectoparasite control as it can cause acaricide resistance and waste of farmer money. Implement cost effective strategies with minimal input and maximum gain of production.

In all by proper management, control and preventive measure by farmer can minimize parasitic infestation and ensures well being of its livestock and minimal damage to host and lead to proper farm management.