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The artificial intelligence (AI) world is quickly growing as it reaches several different industries. You currently will see AI used for many different purposes from agriculture to automotive; with the passage of time you will see even more of it. Agriculture is one of the most important branches of the IT industry. Agriculture is an important industry and is a big part of our economy’s base. In terms of annual sales, the agricultural industry contributes to our economy almost 17%.AI is becoming a technical advancement that boost and protects crop yield, as climate change and populations rise. Here in this chapter basics of Artificial Intelligence have been discussed how it can be related to agriculture.

1. Introduction

Artificial Intelligence has become most prominent in current generation. Every field is utilizing Artificial Intelligence for their better results and which also result in saving a lot of time. As Artificial intelligence is boosting different sectors to increase the productivity and efficiency and its utilization across different sectors like in the field of CIVIL Artificial Intelligence can be used to analyze the structures of buildings, dams etc., and Artificial Intelligence solutions are assisting in so many ways to overcome the traditional challenges in every field.

I. What is Artificial Intelligence

Artificial Intelligence is one of the most prominent field of Computer Science Engineering which attempts to redefine the tasks which are carried out by humans in their daily life with better results and maximum accuracy. Artificial Intelligence is actually meant to ease the work of human where the word artificial states the work done without any human interference and intelligence states the capabilities like human brain to perform tasks. The field artificial Intelligence has given so many definitions from time to time which can be typically stated as

Micropropagation through artificial seeds may be commercially exploited on a large scale, generating millions of plantlets within a few days, and this may become a profitable multibillion rupees industry in near future. This technology would be feasible and even competitive economically with the other seed production methods.

In the near future, the synthetic seed technology could be the key to overcome these problems, e.g., through automated procedures of artificial seed production (Aitken-Christie et al. 1995) followed by autotrophic micropropagation (Jeong et al. 1995). The synthetic seed systems coupled with artificial intelligence and microcomputer systems like the most advanced robots, which can mimic the motions, and functions of living beings (i.e. automated encapsulations). It would tremendously increase the efficiency of encapsulation and production of artificial seeds, and revolutionized the plant propagation method in the years ahead. This technology is gradually moving towards the commercial propagation of high value crops. However, there is a great need for refinement of this technology by tackling of certain technical problems such as the need to produce high quality and high fidelity somatic embryos and to avoid the genetic instability and variability of tissue culture derived plants. The somatic variation can be overcome if the process and regulation of somatic embryogenesis and origin of somaclonal variation are well understood. The understanding about the storage, transport, handling growth habit and harvest index of artificial seeds is essential. The efforts are also needed to increase the output of embryos or plants per gram of callus tissue and conversion frequency of artificial seeds are also needed.

Results of intensive researches in the field of synthetic seed technology seem promising for propagation of crop plants. However, as described in literature, the major stumbling block in establishing artificial seed production as a viable technology is a lack of understanding of the somatic embryo process and an inability to consistently produce high-quality propagules that can germinate in a soil environment with an acceptably high success rate7. Several aspects of the techniques are still underdeveloped and hinder its commercial application.

10.1. LACK OF STANDARD PROTOCOLS

The synthetic seed technology application in a commercial scale is still hampered by the low efficiency of the protocols and logistic behind it. Till today standard protocol for synthetic preparation is available for a limited number of plant species.

Artificial seeds have been widely used for micro-propagation of many plant species. Establishment of gene banks for ex situ conservation of plant germplasm in the form of field gene banks, seed gene banks, in vitro collections, and cryogenically preserved tissues is a common practice (Withers 1983; Rao, 2004; Borner, 2006). Alginate encapsulation provides a viable approach for in vitro germplasm conservation as it combines the advantages of clonal multiplication with those of seed propagation and storage (Standardi and Piccioni, 1998; Ara et al., 2000).

The main aim of artificial seeds is to obtain true to type plants to maintain the germplasm, but, however, during tissue culture, there is a chance of genetic aberration which is commonly known as somaclonal variations. Larkin and Scowcroft (1981) for the first time used the word ‘somaclonal variation’ to describe these variations as displayed among the plants derived from tissue culture. It is clearly understood that genomes modify themselves when exposed to unfamiliar conditions, and these modifications are best described as programmed loss of cellular control (Phillips et al., 1994).

Many researchers successfully prepared synthetic seeds of crop plants. The major success of this technology is being elaborated in this chapter.

8.1. FIELD CROPS

Rice is the world’s most important food crop and a primary food source for more than one third of the world’s population. This crop has received considerable attention in biotechnology research progammes. Research in artificial seeds in rice is not scanty and this technology through somatic embryogenesis would offer a great scope for large-scale propagation of superior elite hybrids (Brar and Khush, 1994). However, success on artificial seeds research in field crops, especially cereals is still in infancy. However, many workers successfully encapsulated somatic and androgenic embryos of cereal crops (Datta and Potrykus, 1989; Suprasanna et al., 1996; Roy and Mandal, 2004 & 2008). Brar et al. (1994) emphasized the need for research on artificial seeds in rice through embryogenesis and outlined its impact on mass propagation of true-breeding hybrids. Somatic embryogenesis can also be used in the regeneration of genetically transformed plants (Vicient and Martinez, 1998). Subsequently those somatic embryos could be economically and successfully propagated though synthetic seed technology.

Plant tissue culture is mainly referred to as mass-multiplication of in vitro derived plantlets grown under controlled environment. Subsequently, the production of artificial seeds from in vitro grown plant propagules is also a method of mass-production of true-to-type plantlets. Micropropagation allows rapid and mass production of high quality, disease free and uniform planting material irrespective of the season and weather. Micro-shoots on being transferred to ex vitro conditions are exposed to abiotic (altered temperature, light intensity and humidity conditions) and biotic stress conditions i.e. soil micro-flora, so there is need for acclimatization for successful establishment and survival of plantlets (Deb and Imchen, 2010). In order to increase growth and reduce mortality in plantlets at the acclimatisation stage, research has been focused on the control of the environmental conditions (both physical and chemical) and to acclimatize the plants to compete with soil microflora (Mathur et al., 2008). In this chapter methods of acclimatization of plantlets derived from simple plant tissue culture or from synthetic seeds are discussed.

In fact, as the concept of synthetic seed involves the use of small propagules and enables the direct sowing of this material in vitro or in vivo, the technology could provide great flexibility to the breeders by not only reducing the costs when large quantities of propagules are required for handling, shipping and planting, but also eliminating the acclimation step when direct sowing in vivo is applied (Onishi et al. 1994).

The artificial seed technology has been applied to a number of plant species belonging to angiosperms. The exact application of artificial seeds will vary from species to species. In self-pollinated crops that currently have good seed production systems, synthetic seeds will not have any practical applications, but in cross pollinating species, especially those where seed production is difficult and expensive, synthetic seeds offer many advantages and opportunities. The importance of encapsulation technique as an aid to propagation in various crop plants has been discussed by many workers. By combining the benefits of vegetative propagation system with the capability of long-term storage and with clonal multiplication, synthetic seeds have many diverse applications in agriculture (Gray and Purohit, 1991; Redenbaugh et al., 1991; Redenbaugh, 1993). In some species seed propagation is not successful. The reason behind this may be due to heterozygosity of seed, small sized seed, presence of reduced or insufficient endosperm, and seedless varieties of crop species like grapes, watermelon, mango, guava etc. Sometimes association of mycorrhizal fungi is essential for seed germination, for example orchids. The germination of these seeds under natural conditions or under control environment is not possible. Propagating of these species through synthetic seed is the added advantage. The possible implications of synthetic seed technology have been detailed hereunder.

As stated by Murashige’s definition, artificial seed (or synthetic/synseed) technology was initially restricted to species in which somatic embryogenesis was possible. Later, Bapat and co-workers (1987) proposed to broaden the technology to the encapsulation of various in vitro-derived propagules, and they used axillary buds of Morus indica as a first example of this new application. The new concept paved the way for the encapsulation of explants other than somatic embryos, and to the formulation of a new definition of artificial seeds (Aitken-Christie et al. 1995) as “artificially encapsulated somatic embryos, shoots, or other tissues which can be used for sowing under in vitro or ex vitro conditions”. In other words, the “new” artificial seed, lost the original bond of containing an embryo (zygotic or somatic), can now contain any kind of explant from tissue culture (such as axillary buds, shoot tips, nodal segments, bulblets, protocorms, callus samples, cells) which, following ‘germination’, will evolve into a plantlet or a shoot (artificial seed conversion) or will produce new cell proliferation (artificial seed regrowth).

Realization of synthetic seed technology requires manipulation of in vitro culture system for large-scale production of viable materials for preparation of synthetic seed, subsequently conversion into complete plants under in vitro as well as in vivo conditions. Somatic and gametic embryogenesis that enhanced axillary bud proliferation are the efficient techniques for rapid and large-scale multiplication of desirable plant species. Plant tissues such as somatic embryos, apical shoot tips, axillary shoot buds, embryogenic calli, and protocom-like bodies are potential micropropagules that have been considered for creating synthetic seeds. Encapsulations of somatic embryos, apical and axillary shoot buds, and regeneration of whole plants from them have been reported for a number of plant species (Redenbaug et al., 1986; Mathur et al., 1989; Ganapathi et al., 1992; Lulsdorf et al., 1993).

The artificial seed production technique was first used in clonal propagation to cultivate somatic embryos placed into an artificial endosperm and constrained by an artificial seed coat. Today artificial seeds represent capsules with a gel envelope, which contains not only somatic embryos but also axillary and apical buds or stem and root segments (Vdovitchenko and Kuzovkina, 2011).

The prime requirements for preparation of artificial seeds are high frequency somatic embryogeniccalli, synchronous embryo development and maximum conversion of embryos into plants. Success in production of synthetic seeds mainly depends on how best callus development and plantlet regeneration are achieved. However, over time the morphogenetic competence of differentiated cultures declines (Lynch and Benson, 1991). Therefore, the primary goal of synthetic seed production is to produce somatic embryos that resemble more closely to the true seed embryo in storage and handling characteristics so that they can be utilized as a unit for clonal propagation and germplasm conservation. Synthetic seeds may be hydrated or dehydrated and may be quiescent or not. Encapsulation of micropropagules enables to satisfy the requirements of synthetic seed development. The gelling agents used for encapsulation for production of synthetic seeds act as protective cover. The encapsulated synthetic seeds also contain growth nutrients, plant growth promoting microorganisms (mycorrhizah, Rhizobium, etc.), and/or other biochemical constituents necessary for optimal embryo-to-plant development (Fig. 4.1). Fungicides may also be used in the liquid gelling medium to protect them during storage and germination in vitro and in vivo.

To mimic the natural seeds, the embryos from cultures are encapsulated in a nutrient gel containing essential organic/inorganic salts, carbon sources, plant hormones and antimicrobial agents and coated completely to protect the embryos from mechanical damage during handling and to allow the development and germination without any undesirable variation. When looking at the history of synthetic seed technology, a wide number of encapsulating agents have been tested in time for their capacity to produce beads like, potassium alginate, sodium alginate, carregeenan, agar, agarose, guargum, polyox, gelrite, sodium pectate, carboxymethyl cellulose, nitrocellulose, ethylocellulose, polyethyleneamine (Kersulec et al., 1993), chitosane (Tay et al., 1993), tracanth gum etc. have been tested as hydrogels (Table 3.1), out of which alginate emasculation was found to be more suitable and practical for synthetic seed production. Some plants exudates of arabic (Acacia senegal), karaya (Stereculsia sp.), or seed gums of gaur (Cyamopsis tetragonoloba), tamarind (Tamarindus indica) or microbial products like dextran, xantham are also being used for encapsulation.

2.1. LABORATORY SETUP

The setting up of a tissue culture laboratory needs proper planning. It depends on the nature of research works to be under taken and/or commercialization of tissue culture technology and the availability of space. The ideal tissue culture laboratory should have the following components:

1. Store facility for chemicals
2. Media preparation room
3. Autoclave room
4. Storage facilities for autoclaved laboratory-ware and media
5. Washing facilit
6. Culture room
7. Inoculation room
8. Instrumentation room
9. Hardening facility

Introduction

Progress in plant biotechnological research has opened many avenues for basic and applied research in the field of crop plants. Plant tissue culture is an important component of biotechnology that involves in the improvement of crops. Besides this, plant tissue culture provides a good system for many basic studies in plant breeding, plant physiology, genetics and cell biology. Further, manipulation of cells through the modern technique of genetic engineering may lead to an introduction of new gene(s) to a host plant and the techniques of genetic engineering rely on plant tissue culture techniques. The regeneration of plants through plant tissue culture and their subsequent acclimatization and delivery to the field possesses many problems to make tissue culture technology a viable alternative proposition. The successful development of encapsulation technique for preparation of plant propagules in a nutrient gel has initiated a new line of research on artificial seeds. Application of this technology has been well recognized in several agronomically important crops and forest trees. Artificial seeds make a promising technique for propagation of transgenic plants, non-seeds producing plants, polyploids with elite traits and plant lines with problems in seed propagation.

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.

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.

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.

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

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%).

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.

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.

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.

Vitamin A

Source of Vitamin

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

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.

HAEMOPROTEUS

Host

Infection with Haemoproteus species is host specific.

H. meleagridis – domestic poultry and pet birds

H. olumbae in pigeons

H. nettionis in waterfowl.

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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

A turkey coronavirus (TCV).

Hosts

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

(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.

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.

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.

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:

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.

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.

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.

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.

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.