eChapters

ILT is an acute viral disease of chickens, pheasants and peafowl characterized by marked dyspnea, coughing, gasping and expectoration of bloody exudate. The disease is worldwide.

Hosts

Chickens particularly susceptible; reported to occur in pheasants and peafowl.

Age Range

All ages susceptible but is most often found in adult (mature or nearly mature) commercial chicken layers.

IB is an acute, highly contagious, viral disease of chickens characterized by respiratory signs (gasping, sneezing, coughing, and nasal discharge), the severe renal disease associated with neurotropic strains, and a marked decrease in egg production. It is a serious cause of sub-optimal egg production and poor egg quality. This disease is worldwide in ditribution.

Hosts

Chickens only. Recently IBV has been detected in species other than chickens. The disease may be produced only in chickens, IBV may multiply in other species of birds and be a source of infection.

Etiology

IB is caused by the avian coronavirus; numerous strains of infectious bronchitis virus (IBV) exist because of high genetic diversity and cross protection between strains is not reliable.

This ‘virus’ is widespread in commercial flocks worldwide, but its taxonomic position is not determined. The disease is characterized by aplastic anaemia and generalized lymphoid atrophy with a concomitant immunosuppression. Consequently, infectious anaemia is frequently complicated by viral, bacterial, or fungal infections.

Occurrence

Chickens up to 3 weeks of age are most susceptible.

Adenoviruses have been found in several species of birds and animals. There are at least 12 serotypes of chicken adenoviruses. The chicken adenoviruses are host specific, meaning they will not infect other animal species. Avian adenoviruses are divided into three major groups. Members of each type may share group antigens, but there is no common antigen shared between types.

Quail bronchitis (QB) is caused by group I (aviadenovirus). QB is an acute respiratory disease of bobwhite quail, occasionally with high mortality. Disease has sporadic occurrence many parts of the world. QB virus is closely related to the prototype CELO (chick embryo lethal orphan) virus, which is cause of high mortality in chicks.

IBH is an adenovirus infection of young chickens characterized by sudden onset and sharply increased mortality, short course, anaemia, and hepatitis often accompanied by intranuclear inclusion bodies. It is described in Canada, USA and many other countries.

Etiology

Group 1 adenovirus. First reported in Pakistan in 1987, where it caused a devastating effect on broiler industry. It has spread to all continents.

EDS 76 is an infectious disease of laying hens caused by hemagglutinating adenovirus and characterized by failure to achieve production targets or by the production of thin-shelled or shell-less eggs in otherwise healthy birds.

This important disease caused loss of egg production for several years - vaccination introduced the disease and a new vaccine virtually eradicated it.

(Tenosynovitis; Ruptured gastrocnemius tendon; Reovirus infection)

Viral arthritis is a reovirus infection primarily of broilers characterized by arthritis and tenosynovitis (primarily of the tarsus and metatarsus, the digital flexor and tarsometatarsal extensor tendons) and, occasionally, by rupture of the gastrocnemius tendon(s) resulting in lameness and condemnations at slaughter. The disease is reported worldwide.

Fowl pox is a slow spreading viral disease of chickens, turkeys and other birds characterized by cutaneous lesions on the un-feathered skin of the head, neck, legs and feet and/or by diphtheritic lesions in the upper digestive and respiratory tract. The disease is worldwide in distribution.

Occurrence

Among poultry chicken and turkey are more susceptible. Other birds include pigeons, canaries, psittacines and wild birds. Fowl pox has been reported from more than 200 species of birds. The incidence is severe in multiple age groups and intensive poultry farming areas.

IBD is an acute, contagious, viral disease of young chickens characterized by diarrhoea, vent pecking, trembling, incoordination, inflammation followed by atrophy of the bursa of Fabricius (BF) and by a variable degree of immunosuppression.

In the USA the disease was reported in Gumboro, Delaware in 1962, hence the name. The occurrence is worldwide.

Marek’s disease is a herpesvirus-induced neoplastic disease of chickens characterized by infiltration of various nerve trunks and/or organs with pleomorphic lymphoid cells. Marek’s disease is world wide in distribution. Marek’s Disease has been named after Josef Marek who published the disease in 4 roosters in 1907.

Occurrence

In chickens only, however turkeys and quail have limited susceptibility. Lesions similar to MD have been seen in pheasants, ducks, pigeons, geese, canaries, budgerigars, swans and great horned owls. However, aetiology for lesions in these species has not been proved. It may appear at 3-4 weeks but usually after eight weeks, with major losses from 12-25 weeks. Morbidity and mortality varies depending on the virulence of MDV.

LL is a retrovirus-causes, neoplastic disease of semi-mature or mature chickens characterized by a gradual onset in a flock, persistent low mortality and neoplasia of, the bursa of Fabricius (BF) with metastasis to many other internal organs especially the liver, spleen and kidney.

The neoplastic disease primarily of broiler breeders and broilers causing serious economic losses in the commercial poultry industry. A case has been recorded in a budgerigar.

Etiology

ALV-J subgroup, identified in 1988. It became widespread in commercial meat type poultry in the 1990’s. Transmission of ALV-J is much higher than other subgroups thus making control much more difficult.

Term endotheliosis designates a variety of syndrome caused by a reticuloendothelial virus (REV). REV caused syndromes have been demonstrated world wide.

Etiology

Based on replication of the virus in chicken fibroblast cell culture, two strains are known: replication defective T strain and the non-defective A strain. The REV manifests three distinct diseases syndromes:

Etiology

Avian Nephritis Virus (ANV), an RNA virus is Astro virus under the genus Avastrovirus in Astroviridae family. Strains of ANV exist. ANV is very resistant and stable in the environment.

AI is a viral disease affecting the respiratory, enteric or nervous system of many kinds of birds. The most virulent form is an acute, generalized disease characterized in poultry by a short course and extremely high mortality.

(AE; Epidemic Tremor; Infectious Avian Encephalomyelitis)

AE is a viral infection of chickens, turkeys, pheasants and cortunix quail characterized in young birds by ataxia progressing to paralysis and, usually, by tremors of the head and neck. Infected adults usually show no signs. AE is world wide in distribution.

Etiology

A turkey coronavirus (TCV).

Hosts

Turkeys of all ages, but the disease is mostly observed in young turkeys (first few weeks old).

It is an acute disease of turkeys, occurring in 6-7 wk. -Old turkeys, but has been seen in younger and older turkeys as well. The disease is worldwide in distribution.

Etiological Agent

It belongs to adenovirus type II. A serologically indistinguishable virus from HE virus, causes marble spleen disease (MSD) in confinement reared pheasants (3-8 months old). The disease shows predominantly respiratory signs. A virus of the same group causes avian adenovirus group II splenomegaly (AAS) in chickens.

Etiology Herpes Virus

Variation in pathogenicity of virus strains has been reported, but all strains appear identical immunologically.

Occurrence

The disease was first reported in the Netherlands in 1923. The disease has been confirmed in France, Belgium, Canada, India, Thailand, England, Hungary, Austria, Denmark and Vietnam, and suspected in China.

DVH is a highly fatal infection of young ducklings. Lesions are primarily in the liver.

It is an acute disease of pheasants, chukars, partridges, turkeys, ducks, pigeons and wild birds. The viruses of EEE and WEE are of public health importance as they infect humans and occasionally cause fatal disease. The disease is further significant because of its link to disease in horses.

Etiology

The arboviruses are grouped into 12 different families. The five arboviruses causing disease in birds are Eastern equine encephalitis (EEE) virus, Western equine encephalitis (WEE) virus, Highland J (HJ) virus, Israel turkey meningoencephalitis (IT) virus and West Nile Virus WNV. The first three are in Togaviridae, and IT and West Nile Virus (WNV) are in Flaviviridae.

WNV was first identified in the West Nile district of Uganda in 1937. Reported in Western Hemisphere for the first time in 1999, in New York City. The virus had until that time been found only in Africa, Eastern Europe, West Asia and the Middle East.

Introduction

This is a disease mainly of the respiratory system affecting domestic poultry, wild birds and zoo birds. Systemic aspergillosis affecting visceral organs and other tissues of the bird’s body is also reported. Reports are also available on eye and brain infections.

Introduction

1. Serious outbreaks of thrush have been observed in chickens, pigeons, geese, turkeys, pheasants, quail, peacock and many other species of birds.
2. Candida albicans is the most commonly isolated fungus from the outbreak. Mucor spp. and Aspergilli were also found in some cases.
3. The outbreaks are associated with unhygienic conditions and nutritional deficiencies. Infection is more common in young birds up to 10 weeks of age. Morbidity is very high and mortality ranges from 10-75%. Clinical signs are not specific. Poor growth and ruffled feathers are only clinical signs.

Etiology

Cryptococcosis (KRIP-toe-cock-co-sis) is caused by the fungus, Cryptococcus neoformans (KRIP-toe-cock-kus knee-O-for-mans). It is found worldwide and primarily affects cats and people with weak immune systems.

It is a fungal infection of skin and the term favus is used for the disease in poultry. The disease is world wide in distribution.

Etiology

Microsporum gallinae, a fungus. The fungus is zoonotic. Lesions of ring worm are produced in humans in contact with infected birds.

Diseases caused by toxic metabolites of fungi are called mycotoxicosis. It affects man and animals including birds. Fungi which grow on feeds and grains in an unfavorable environment mostly cause mycotoxicosis in birds.

The disease is worldwide in distribution and remains the major parasitic problem in the poultry industry. The problems occur principally in poultry maintained on deep litter.

Etiology

Coccidiosis of all classes of poultry is caused by one or more of the many species of coccidia of Eimeria species. In chickens nine main species are encountered. Eimeria tenella, E. necatrix, E. maxima, E. acervulina, E. mitis, E. mivati, E. hagani, E. brunetti and E. preacox.

Cryptosporidiosis is a protozoan disease.

Species

1. C. meleagridis: Infects small intestine.
2. C. baileyi: Infects digestive tract (bursa of Fabricius and cloaca), kidneys and respiratory tract.

Histomoniasis is a protozoan disease.

Etiology

Histomonas meleagridis.

Hosts

Mainly disease of turkey but has also been reported in chickens, peafowl, grouse, quail and gallinaceous birds.

Etiological Agent

Trichomonas gallinae, a flagellate protozoan. Strains vary in pathogenicity. The disease continues to be of significance in pigeons and doves. It has also been reported in raptors.

Introduction

Chickens are considered one of the most important hosts in the epidemiology of Toxoplasma gondii infection because they are an efficient source of infection for cats that excrete the environmentally resistant oocysts and because humans may become infected with this parasite after eating undercooked infected chicken meat.

Poultry meat is an important part of cuisine, consumed widely all over the world; therefore, consumption of uncooked or not properly cooked poultry meat may pose a risk factor for T. gondii infection in humans or animals.

Introduction

A. Common species of nematodes encountered in poultry are:

1. Syngamous trachea (in the respiratory tract) large 2.00cm size live in the trachea and larger bronchi. Many species of domestic and wild birds are affected. Dyspnea, gasping and head shaking are main clinical signs. Treatment is difficult.
2. Ascaridia galli (in the intestine) They parasitize chicken, turkey, pigeon, quail and guineas. In younger birds parasites cause enteritis. In heavily infected birds clinical signs are emaciation and diarrhea.

Introduction

1. Various genera of tapeworms are found in poultry. They are:
   1. Raillietina spp.
   2. Choanotaenia spp.
   3. Davainea spp.
   4. Amebotaenia spp. and
   5. Hymenolepis spp.
2. Tapeworms mainly parasitise the small intestine. Tape worms deprive the bird of its nutrition and cause weight loss and decreased egg production.
3. Out of 3 species of Raillitina, Raillietina echinobothrida is one of the pathogenic species as it produces granuloma at its attachment site (nodular disease).
4. They all require intermediate host for their development.
5. Intermediate hosts are common houseflies, ants, beetles and grasshoppers, which makes control of tapeworms difficult.

HAEMOPROTEUS

Host

Infection with Haemoproteus species is host specific.

H. meleagridis – domestic poultry and pet birds

H. olumbae in pigeons

H. nettionis in waterfowl.

LICE

Introduction

Lice are common ectoparasites of birds. There are many species of bird lice and are found on chicken, turkey, guinea fowl, duck, goose and pigeon. Lice species prefer a different part of the body. Most of them are straw colour and measure 1-10 mm. Lice from one host can parasitise another host if they are in close contact. For example, a louse from chicken can parasitise guinea fowls kept on the same premises. Hence, the species of lice is determined if cross contamination from another species is suspected. Lice are not highly pathogenic to mature birds. However, severe lousiness may lead to weight loss, as well as low production and death.

Vitamin A

Source of Vitamin

Berseem, legumes, alfalfa or other grass meal, fish oils, yellow corn, palm oil, commercial Vitamin A concentrate

CALCIUM & PHOSPHORUS

Source of mineral

Soluble grits (Limestone grits containing chiefly CaCo3) which is soluble in acid medium of crop. It differs from insoluble grits (gravel, granites, sand etc.) which acts only mechanically in the gizzard.

Pododermatitis or bumble foot has many causes including excess weight bearing from obesity or unequal weight bearing between the two feet as a result of lameness of one foot, causing less weight to be placed on that foot and more on the contralateral foot, or from abnormal abrasions of the plantar surface from inappropriate substrate (too sharp or rough, wire, etc.), decreased blood supply to the foot (sometimes from lack of exercise), trauma, or standing for prolonged periods of time, especially in ducks that are not provided with adequate swimming opportunities.

Bumble foot is commonly seen in waterfowl under one or more of the following conditions; obesity, hard substrate, lack of access to water to swim in, malnutrition and underlying disease.

This is localized infection of the feet. It is seen as bulbous swelling of the footpad and surrounding tissues. It appears usually after an injury to the foot pad and causes lameness in one or both feet. Pododermatitis is divided into varying grades depending on the literature source used, but generally includes mild, moderate, and severe grades with the severe grades including osteomyelitis. Infection by various bacteria commonly occurs and superficial wounds may not be present. Sometimes ulcers are formed on the planter surface of the foot. The layers become lame and production lowers, sometimes completely stops. On opening the swelling a foul smelling thick pus is found. The condition is more common in heavy breeds. Early surgery and antibiotic therapy may control the condition. Removal of high roosts reduces the incidence.

Cage layer fatigue is a term used to describe leg weakness and acute deaths in chickens in cages, and is caused by inadequate calcium, phosphorus and Vitamin D levels in the blood stream. Calcium is required for muscle function, bone formation, and egg shell formation. This condition may be seen even in floor birds under certain conditions. It is seen most often in young hens early in production.

Introduction

Although the causative agent for the condition has not been identified, experimental studies indicate the association of parvovirus and or Astrovirus. Under experimental conditions, the virus induces clinical signs onlyin fast growing broiler chickens. The clinical signs, based on experimental inoculation of chickens, consist of watery or mucoid mustard yellow colour diarrhoea within 3-5 days after infection. Chickens become stunted, and a variable number of such chickens die during 10 and 20 days. Pronounced weight loss is in around four week’s age. The mortality is low (5 - 10%) however, the morbidity is very high (50 - 80%).

Introduction

1. The condition has been reported the world wide in growing broiler chickens.
2. The affected birds show clinical signs usually during 4 - 5 weeks of age. The clinically affected birds are smaller, listless with ruffled feathers, pale head and shrunken comb. Severely affected birds have distended abdomen, which restricts their normal movement. Death may occur suddenly, and not all the broilers which die of the condition have ascites. The incidence of the disease varies between 2 to 20%.

Introduction

Hypoglycemia Spiking mortality syndrome is a disease in broilers, characterized by low mortality with sudden onset of high mortality. The affected birds are clinically hypoglycemic.

There is no known aetiology.

The condition is characterized by proventriculitis and dilatation of proventriculus.

Etiology

The cause of transmissible viral proventriculitis (TVP) is a birnavirus referred as Chicken proventricular necrosis virus (CPNV). TVP is a disease of 3-8 week-old broiler.

Seen in mature chickens. Condition results from myocardial degeneration which causes bilateral ventricular hypertrophy and dilation. Etiology is not known.

Round heart disease in turkey causes mortality in 1-4 weeks of age. Lesions are severe cardiomyopathy, ascites, hydropericardium and generalized congestion of tissues. No aetiology is known.

THEORETICAL ORIENTATION

The word “democracy” is derived from the Greek roots - ‘cracy’ meaning ‘rule of and ‘demos’ meaning ‘the people’. It is governance of the people, by the people, for the people. Rule by majority is, no doubt, an important feature of this system of governance; but the more important ingredient is rule by consultation - consultation between the people’s representatives on one hand and consultation with the officers on the other. ‘Decentralization’ means devolution of central authority among local units close to the areas served. Where authority is devolved by this process on people’s institution, it is ‘democratic decentralization’.

At the instance of the Prime Minister it was decided to give the process of the three-tier administration the strictly Indian name, “Panchayati Raj” which means a system of government. Panchayati Raj was conceived system of democratic local self-Government. Earlier, Mahatma Gandhi also advocated panchayati raj as the foundation of India’s political system, as a decentralized form of government in which each village would be responsible for its own affairs. The term for such a vision was Gram Swaraj (“village self-governance”). The institution of Panchayat represented not only the collective will, but also the collective wisdom of the entire rural community.

The Balwant Rai Mehta Committee, headed by M P Balwant Rai Mehta, was a committee appointed by the Government of India in January 1957 to examine the work of the Community Development Programme (1952) and the National Extension Service (1953) and to suggest measures for their better work. The committee recommended the establishment of the scheme of ‘democratic decentralisation’ which finally came to be known as 'Panchayati Raj' which would be a 3-tier system - 'Gram Panchayat' at the village level, Panchayat Samiti at the block level, and Zilla Parishad at the district level.

This practical assignment is designed in a way that students will acquire knowledge on various development departments in the district, especially on organizational structure, functioning and activities of any agency like District Rural Development Agency (DRDA).

PURPOSE

To get the students acquainted with the organization and functioning of DRDA.

To give the students a brief idea about the organizational structure and functions of other development departments at district level.

This practical assignment is conceptualized and designed to acquire practical learning experience through various activities implemented by NGOs in improving the livelihood of the targeted group. The assignment also projects a clear picture about the objectives, structure, functioning and activities of NGOs.

PURPOSE

To make the students acquainted with the NGOs and their learning experience in rural development.

THEORETICAL ORIENTATION

A non-governmental organization (NGO) is a not-for-profit organization that is independent from states and international governmental organizations. They are usually funded by donations but some avoid formal funding altogether and are run primarily by volunteers. NGOs are highly diverse groups of organizations engaged in a wide range of activities, and take different forms in different parts of the world.