The presence of undigested feed in droppings is commonly known as ‘feed Passage’. This will lead to poor performance of flock involving less weight gain, poor growth; disturb flock uniformity and ultimately the flock production.
This condition is more prevalent in young flocks rather than in older ones. If it is untreated it may cause the significant mortality from 2% to 50%.The mortality is not the actual loss in this condition but the flock get disturbed in skeleton development and flushing that leads to less uniform flock and ultimately future peak production and is persistency is at risk. Bird become immune compromised for other diseases.
This condition has not one or two causes but a list that can be the possible factors for this condition. It’s actually the disturbance in normal gut micro flora that leads to high count of clostridium in the gut that are gram-positive, obligate, anaerobic bacteria It is usually isolated on blood agar, incubated anaerobically at 37°C (98.6°F), on which it produces a double zone of hemolysis.
There are two primary C perfringens types, A and C, associated with necrotic enteritis in poultry. Toxins produced by the bacteria cause damage to the small intestine, liver lesions, and mortality. This disturbance in the normal gut micro flora can be named as Dysbiosis , Dysbacteriosis , Feed passage syndrome, wet litter syndrome, unspecific enteritis.
- Undigested feed in droppings
- Droppings lose their shape and compactness and watery and without white uric acid white cover.
- Reluctant to move, lethargic and depressed
- Bird Hides under drinkers
- Light weight , keel bone apparent
- Water to feed ratio increases
- Poor pigmentation of legs
- Ruff feathers
- Feed in the crop and Poor FCR
Possible Causes of the Undigested Feed:
Infectious diseases that affects gut , proventriculus , gizzard and intestinal epithelium includes worms infestation ,coccidiosis and enteritis
Mycotoxicosis different types of mycotoxins affect the functioning of the digestive system, hindering proper digestion of feed.
Antinutritional factors (gizzerozine, biogenic amines) and some vitamin deficiencies cause gizzard erosions, worsening the process of feed grinding.
Rancid fats are claimed by some authors as a common cause of feed passage, but many otherresearchers state that feeding broilers with of high peroxide value fats does not produce significant lesions in the digestive system (Choque et al, 2007; Baucells et al, 2008; McGill et al, 2011)
Intestinal changes in intestinal motility, modified cations of gastric acidit reduction in the production of bacteriostatic peptides in the pancreas alterations in the amounts of mucus produced or in its composition.
High water TDS level may cause the significant entritis in birds if condition remain unchecked for a longer time.Poultry safe level of TDS is 150 to 1000. Above this not acceptable in poultry as upto 500 is ideal one. pH of water should be from 6.5 to 7.5 .ideally its more like to 6.8 to 7.00
It is the main cause of many diseae outbrakes as litter should not too dry or not too humid. Dry litter may cause rspiratory problems . wet litter will provide the growing substrate to spores of clostridium .litter should have upto 30% moisture. Humidity inside the shed should not excede from 70 percnt.
Any perturbation in gastroenteric physiology or immunity of the bird caused by temperature stress (heat or cold) or other environmental discomfort can cause dysbiosis and/or enteritis associated with lower absorption of nutrients by the host.
Exposure to the stress hormones norepinephrine and epinephrine, signif cantly increases the proliferation of several enteropathogenic bacteria, Such as Escherichia coli, Yersinia enterocloitica, Pseudomonas aeurinosa, Salmonella enteritidis, Salmonella cholerasuis, and Salmonella typhimurium.
Even under the best nutritional conditions, environmental stresses in commercial production conditions can increase intestinal bacteria proliferation and make animals more prone to dysbiosis. This situation is more frequent in young animals with unstable and immature microflora or immunosuppressed animals.
Post Mortem Findings:
Emaciated and dehydrated bird that is due to enteritis and diarrhea
Cholangiohepatitis (CAH) in chickens is characterized by inflammatory proliferative and dystrophic necrobiotic alterations in bile ducts and the liver parenchyma. Usually, no clinical signs are observed. The increased daily mortality is insignificant, although in some chickens, a retarded growth and dehydration could be present.
- Undigested feed in the intestine increased water/feed ratio.
- Inflammation and congestion of intestines.
- Thin, transparent, fragile intestinal wall
- Intestinal wall loose its thickness
- Intestinal villi and mucosa slaughed off
- Presence of worms i.e ascardia
- Greenish or yellowish material inside the intestine
- Kidneys may be sawollened and urates deposit there
- Gas formation in intestine
- Severe enteritis including hemorrhages
In many occasions dysbacteriosis is accompanied by lesions in gizzard. The reason for this phenomenon is not known exactly, but could be explained by the investigations of some researchers that link increased occurrenceof gizzard erosions to flora imbalance, specially to higher Clostridium counts, in some parts of digestive tract (Novoa-garrido et al, 2007).
- 20% Bile Positive (+ve)
- Capsule Positive (+ve)
- Catalase Negative (-ve)
- Flagella Negative (-ve)
- Gas Positive (+ve)
- Gelatin Hydrolysis Positive (+ve)
- Gram Staining Gram-positive
- Hemolysis Positive (+ve)
- Indole Negative (-ve)
- Motility Negative (-ve)
- Nitrate Reduction Variable
- Oxidase Negative (-ve)
- Shape Rod shaped; straight rods with blunt ends
- Spore Positive (+ve)
- 2 % NaCl Positive (+ve)
- 6.5% NaCl Negative (-ve
Prevention and Treatment:
As mentioned above, the main situations in which feed passage occurs is either when there are erosions on thetissues of gut that impair its functioning or when there is intestinal flora imbalance.
Plant extracts can be used to Restore or maintain the integrity of digestive tissues Immunity. some phytochemicals, such as some compounds contained in garlic extract, are able tostimulate local gut immunity (Ota et al, 2012).
Antioxidant compounds, such as those contained in marjoram or cinnamon, are beneficial againstintestinal inflammation.
Improve feed digestibility: Sweet bay induces a higher secretion of bile acids; cinnamon stimulatesthe secretion of digestive enzymes. Improved digestion means that there are less substrates forpathogenic microorganisms to grow.
Direct action on tissues: Chicory is able to modify the morphology of the intestinal epithelium, by increasing the villus length and crypt depth, and thus amplifying the absorptive surface and and maintaining a healthy intestine.
Restore or maintain balance of intestinal microbiota
Microbiocide: cinnamon, marjoram or garlic have proven to be natural bactericides are able to reduce the load of pathogenic microorganisms in case of imbalance. Unlike antibiotics, they do not exert a germicidal action which can reduce the numbers of useful microbes.
Prebiotics: chicory feeds beneficial lactic acid bacteria and promotes their growth exponentially.
- Addition of antibiotics in the feed such
- virginiamycin 20 -40 g/ton feed
- Bacitracin 50 g/ton feed
- lincomycin 2 g/ton feed
- Neomycin 70-140 g /ton feed
- Oxytetracycline 400-600 g ton feed
The minimizing the level of fishmeal, wheat, barley, or rye in the diet can also help prevent this condition. When higher amounts of wheat, barley, or rye are necessary, use of enzymes for non-starch polysaccharides in the feed has reduced the level of necrotic enteritis in flocks fed these cereals.
Treatment for necrotic enteritis is most commonly administered in the drinking water, with bacitracin (200–400 mg/gal. for5–7 days), penicillin (1,500,000 u/gal. for 5 days), and lincomycin (64 mg/gal. for 7 days) most often used. In each case, the medicated drinking water should be the sole source of water. Moribund birds should be removed promptly, because they can serve as a source of toxicosis or infection due to cannibalism.