Digestive system

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What Are the Three Main Functions of the Digestive System?
The seven major parts of the digestive system are the salivary glands, the pharynx, the esophagus, the stomach, the small intestine, the large intestine and the rectum. The crop functions to both soften food and regulate its flow through the system by storing it temporarily. Chickens do not have teeth, so they cannot chew their food. In the large intestine the remaining semi-solid substance is referred to as faeces. Very often the intestine proximal to the intussusception is distended, and the strangulated portion is thickened.

Digestive System of the Dog

Avian Digestive System

The Raticator Here is a safe, humane, non-poisonous way to protect your aviary from from rats and mice. The Raticator will also help protect you and your family from the dangers of Hantavirus and other rodent-spread diseases. This item was formerly known as the Ratzapper. These high-quality products are designed to provide a reliable breeding environment for snakes, geckos, bearded dragons, and other reptiles. General Safety Here is the common-sense approach to keeping your bird safe.

The author discusses subjects from clipping wings to buying toys wisely. Even experienced bird owners should read this article. Foundation for a Healthy Bird A bird suffering from malnutrition will eventually die from organ failure or from secondary bacterial or viral infections that plague a compromised immune system.

Prevent Heavy Metal Poisoning Parrots like to chew on everything, including things that are dangerous to them. Check their environment for items that contain lead, zinc, brass, and copper. These metals can kill or greatly harm your bird.

Please read this important article. How to Manage Feather Picking Does your parrot pluck at his feathers? Most caged birds seem prone to feather picking, but the condition can be treated and prevented.

This article sheds light on the causes and remedies of feather picking. Vitamin A Deficiency Vitamin A deficiency affects the cells that line the respiratory, reproductive, and digestive tracts. As a result, birds can die from secondary infections caused by a weakened immune system and the inability of the bird to heal itself.

Bird Care Guide Must-Reading for those of you who are considering adding a bird to your family. Another Bird Care Guide More required reading for the new bird owner. This article supplements and reinforces the information contained in the bird care article listed above. Avian Health Care Tips Dr. Print out this chart that lists plants, fruits, vegetables and household items that can be dangerous to your bird.

Safe Plants for Birds This is the companion article to the one above. Here is a list of plants that are safe for your bird, at least in reasonable quantities. Egg Binding in Birds Egg binding is the inability of a bird to pass a developed or partially developed egg.

The author of this article believes that nutrition is at the root of egg binding problems. Although the breeder may provide the bird with calcium from a variety of sources, the problem may be the inability of the bird to metabolize the calcium that is readily available in the diet.

Bird House Placement and Care Here's an article about the care and placement of your bird house. Although not a problem for most bird owners, bird dust and feather particles can cause serious damage to lungs. This article by a veterinarian explains why caffeine is so toxic.

How Clean is Clean? Mortality may be high. Campylobacter spp have also been isolated from free-living birds, including migratory birds and waterfowl, crows, gulls, and domestic pigeons; however, disease due to C jejuni jejuni , for example in naturally infected birds, is rare.

Campylobacter GI disease has been reported in exotic pets eg, ferrets, mink, primates, hamsters, guinea pigs, mice, and rats. Although clinical signs vary in these species, they generally include mucoid, watery, bile-streaked diarrhea sometimes with blood , anorexia, vomiting, and fever.

Prolonged infections are possible but uncommon; most infections are self-limiting with mild signs. The following species have been isolated from birds, shellfish, reptiles, marine mammals, and livestock not known to be associated with disease symptoms: C avium , C hyointestinalis lawsonii , C fetus subsp testudinum , C canadensis , C peloridis , C insulaenigrae , C subantarcticus , C volucris , and C ureolyticus previously Bacteroides ureolyticus.

Several of these are implicated in human diseases. Arcobacter spp infecting animals include A cryaerophilus livestock abortion , A butzleri livestock diarrhea, bovine and porcine abortions , A skirrowii sheep diarrhea, livestock abortions , and A thereius porcine abortion. Disease status is unknown, although these species have been isolated from food animals: A cibarious chicken meat, piggery effluent , A trophiarum fattening pigs , and A suis pork meat.

Approximately 11 additional Arcobacter spp found in shellfish, sewage, seawater, sediments, and salt marsh plants are not known to cause diseases in animals or people. C jejuni can stably colonize the small and large intestines, although most animals show cecal and colonic lesions with typhlocolitis. In swine and mice, gross lesions observed in C jejuni enteritis include enlarged and fluid-filled ceca and proximal colons with thickened walls.

Lymph nodes ileocecocolic and mesenteric draining infected sites become significantly enlarged. Infection with particular strains of C jejuni produces bloody exudates with mucus. Histopathologic features include a marked inflammation of the lamina propria, dominated by neutrophilic polymorphonuclear cells and mononuclear cells that sometimes extend into submucosa. Immune cells such as plasma cells, macrophages, and mononuclear cells have been found in smaller numbers in the lamina propria.

Damage to, sloughing of, and ulceration of the epithelial surface and edema have also been seen in most infected species. In pigs and mice, damage to the epithelial surface is associated with the presence of C jejuni at the basolateral surface of the epithelium, in paracellular junctions of the epithelium, and in erosive and ulcerative lesions of the epithelium; there is often a mucopurulent neutrophilic exudate with sloughed and lysed epithelial cells and erosive or ulcerative lesions where C jejuni is associated with the basolateral aspect of sloughing villous tip cells in the colon.

Crypt abscesses and damage to the crypt epithelium are also common findings. Campylobacter spp can be found in both healthy and diarrheic animals; thus, clinical signs and postmortem findings depend on the species and the host animal and its age. Diagnosis of enteric campylobacteriosis relies on isolation of the causative agent using selective media under microaerophilic conditions.

Fresh fecal samples should be collected and transported to the laboratory preferably on the same day and within at least 2 days for processing. Campylobacters are very sensitive to environmental conditions, including dehydration, atmospheric oxygen, sunlight, and increased temperature. Organisms are thin 0. They exhibit a typical spiraling motility. In unfavorable growth conditions, spiral rods undergo a degenerate conversion to coccoid forms.

Campylobacters can be quickly outgrown by contaminating microbes during prolonged transport to the laboratory, and isolation of pure colonies for downstream testing can be difficult. Enrichment is required for most clinical sampling unless material can be transported to the laboratory immediately.

When samples are collected in swabs, the use of commercially available transport tubes containing medium, such as Amies, is recommended. The medium can be plain agar or charcoal-based.

Several transport media have been described for transport of fecal specimens, including Cary-Blair, modified Cary-Blair, modified Stuart medium, Campy thioglycolate medium, alkaline peptone water, and semisolid motility test medium.

Other media are recommended for the isolation of campylobacters associated with reproductive losses. Campylobacter spp do not ferment carbohydrates, and other biochemical characteristics are thus used to identify different species. C jejuni is differentiated on its ability to hydrolyze hippurate, and C upsaliensis has negative or weak catalase production and is differentiated from other campylobacters because of its sensitivity to nalidixic acid. C helveticus is also catalase negative but can be difficult to differentiate biochemically from C upsaliensis relying on distinctive colony morphologies.

Differentiation of subspecies can be necessary for identification of significant pathogens. C jejuni subsp jejuni is the main cause of enteritis, whereas C jejuni subsp doylei has been isolated only from enteritis cases of children and not animals. They can be differentiated by the ability of C jejuni doylei to reduce nitrate. Similarly, C hyointestinalis subsp hyointestinalis can cause bovine and porcine enteritis; however, C hyointestinalis subsp lawsonii has been isolated from the porcine stomach, but it is not known to cause disease.

The subspecies can be differentiated by testing the intolerance of C hyointestinalis lawsonii to 1. Arcobacter spp previously known as aerotolerant campylobacters can also be associated with human and animal diarrhea and with animal abortions. Arcobacters are usually not thermophilic but can be confused with the nonthermophilic Campylobacter spp if aerotolerance is confirmed using standardized suspensions of organisms.

Although most cases of human enteritis are attributed to C jejuni jejuni , C coli , C lari , and C upsaliensis , it has been suggested that the importance of other species also associated with GI illness may be significantly underdiagnosed as a consequence of inappropriate isolation and identification methods.

PCR-based methods effectively identify infection, especially if cultivation is difficult or if the sample has been somewhat mishandled. However, a positive test is not sufficient evidence to determine causation and must be considered in conjunction with clinical signs. Clindamycin , gentamicin , tetracyclines, erythromycin , cephalosporins eg, cephalothin , and fluoroquinolones eg, nalidixic acid are effective against C jejuni , C helveticus , and C upsaliensis.

C fetus , C hyointestinalis , C mucosalis , and C sputorum are usually resistant to the fluoroquinolones yet sensitive to cephalosporins. C coli are sensitive to fluoroquinolones but resistant to cephalosporins.

Susceptibilities to penicillins and trimethoprim are variable across Campylobacter spp. Resistance to the fluoroquinolones, tetracycline , kanamycin , and some other antibiotics has been documented among the Campylobacter spp, mediated by both chromosomal and plasmid mechanisms.