**1. Introduction**

Domestic fowls are the most important protein sources of human populations in every part of the world. As is demonstrated that during the last 30 years, eggs and poultry meat were constantly increasing. Poultry industries make a significant contribution to improving the nutritional status and economic income of many countries of the world [1].

Animal welfare is a big problem in today's factory farming. And the widespread abuse of birds serves as an example of it. Every year, 9 billion chickens are grown and killed for food in America alone. Broiler chickens are the name given to chickens grown on factory farms for meat. They are kept in cramped, gloomy sheds. Despite the meat industry's best efforts to conjure up images of happy birds frolicking in green fields, 99.9% of hens raised for food are kept in factory farms where they are deprived of access to sunlight and fresh air. And it confines them to filthy areas that serve as ideal breeding grounds for disease [2].

Parasitic infections of poultry are the major factors responsible for economic losses through a reduction in productivity and increased mortality. A lot of losses in poultry are linked to disease-causing pathogens such as viruses, bacteria and parasites. Poultry is subjected to a wide variety of diseases including Newcastle disease, salmonellosis, respiratory disease and a large number of ecto-endoparasites. Their diseases are often fatal resulting in high mortality and low productivity. Domestic fowls feed on different types of food materials, these materials include grains, fruits and insects which may harbor infective stages of parasites, particularly gastrointestinal helminths [3].

Gastrointestinal helminths of poultry are commonly divided into three main groups: nematodes, cestodes and trematodes. Nematodes are considered the most important group of helminths of poultry such as the species which belong to the genera *Capillaria*, *Heterakis* and *Ascaridia*. The most important genera of cestodes are *Railleitina* and *Hymenolepsis*. Regarding the types of trematodes, they are not very common like the other groups [4].

Gastrointestinal tract worms, in particular, are known to cause poor feed conversion and utilization that lead to emaciation and poor weight gains. Various ectoparasites are reported in the local fowls such as lice, fleas, mites and soft ticks [5].

In general, there is a need to understand the epidemiology of the various fowl parasites in order to plan strategies to increase the productivity of chickens [6]. Limited work has been done on ectoparasites and endoparasites of fowls in Iraq including the Kurdistan Region [7].

## **2. Types of ectoparasites in fowls**

Ectoparasites of poultry are arthropods that live on the skin and feathers including lice, fleas, soft ticks and mites [8]. Ectoparasite problems may be controlled by:


Members of the animal phylum Arthropoda, which is distinguished by having outwardly segmented bodies, jointed legs, appendages, and chitinous exoskeletons, include poultry ectoparasites [10].

One pair of antennae is linked to the head, three pairs of legs are attached to the thorax, and some mature insects have wings. These characteristics identify lice, flies, bugs, and fleas as members of the class Insecta [11].

Some ectoparasites of poultry such as lice eat the dead cells of the skin and skin acts as a medium through which they suck blood and from which they obtain shelter. Lice may be closely confined to their hosts during their entire life cycle, while other parasites wander freely from bird to bird. Some are highly hosted specific while; some species may maintain host nonspecific relationships [12].
