1Vitamin A deficiency
Vitamin A is an essential vitamin for normal growth and development of poultry, vision and mucosal integrity. It can maintain the integrity of the skin and mucous membranes, resist the invasion of microorganisms and parasitic diseases, enhance the specific immune function of the body; promote the growth of the body and bones, improve fertility, and increase visual pigment. The lack of vitamin A in poultry is mostly caused by insufficient supply in the diet or due to malabsorption, and this disease is prone to occur in young waterfowl.
1.1 Clinical symptoms
When ducks and geese are deficient in vitamin A, the sick birds suffer from mental fatigue, loss of appetite, growth stagnation and weight loss. The feathers are loose, the toes and claws are curled, the gait is unsteady, and severe breathing difficulties may occur.
The characteristic symptoms of this disease: there are a lot of caseous exudates in the conjunctival sac of the diseased birds, and the eyelid is swollen, glued, tearing, and the eyeball is atrophied and sunken, see Figure 1. The mucosa of the oral cavity, pharynx, and esophagus were inflamed, with scattered necrotic foci, and a gray-white pseudomembrane formed on the surface.
In addition, the lack of vitamin A can cause renal dysfunction, resulting in the inability to excrete urate normally. A large amount of urate can be accumulated in the renal tubules, and the deposition of urate can also be seen on the surface of the heart, pericardium, liver and spleen.
1.2 Diagnosis is
based on the history of ducks and geese lacking green feed for a long time and not adding vitamin A to the feed, combined with eye lesions in chicks, gray-white pseudomembranes in the mouth and esophagus, and the decline in egg production, fertilization, and hatchability of adult waterfowl. Make an initial diagnosis. Diagnostic treatment can be achieved by supplementation of green feed and vitamin A in the feed.
1.3 Prevention and control
1.3.1 Preventive measures to
ensure that there is enough vitamin A and carotene in the diet, feed the ducks and geese with green feed, carrots, roots and yellow corn, and if necessary, cod liver oil or vitamin A additives should be given. Once sick ducks are found, feed rich in vitamin A should be added to the diet as soon as possible. Vitamin A is a fat-soluble vitamin that is easily damaged by heat and oxidation. Therefore, it should not be stored for too long in the diet, and it should not be moldy, heated or oxidized.
1.3.2 Treatment measures
When this disease occurs in poultry flocks, 10,000 IU of vitamin A can be added to the diet per kilogram, and eye lesions can be washed with 3% boric acid water once a day, with good results.
2 Vitamin D and calcium and phosphorus deficiency
Vitamin D contributes to the absorption of calcium in the small intestine, and calcium and phosphorus are essential elements for the normal growth and development of bones in poultry. Therefore, when vitamin D, calcium-phosphorus deficiency, and calcium-phosphorus mixing ratio are inappropriate, adult poultry osteomalacia and young rickets are caused. The age of onset is concentrated in 1-6-week-old young birds and egg-laying birds at the peak of egg production, and ducks are more common. It is easy to occur when there is a lack of exercise and sun exposure in the house, and the rainy days are too long.
2.1 Clinical symptoms
2.1.1 The chicks
are manifested as lack of energy, unresponsive, loose feathers, slow growth or complete stop; weak legs, weak legs, deformed or paralyzed, unsteady walking, often crouching, like penguins , In severe cases, he could not stand, barely standing with his legs spread apart in a figure-eight shape; the beak became soft and curved; difficulty in feeding, diarrhea, and discharge of gray or gray-white watery feces.
2.1.2 Adult ducks and geese
are characterized by decreased egg production rate, soft-shelled eggs, and decreased hatching rate of hatching eggs; laying ducks have decreased production or increased soft-shelled eggs, and the tibia is deformed and easily broken; the keel is S-shaped; Lesions in ducks, mainly beak lightening, soft texture, can be bent. Long bones are poorly calcified, severely decalcified, bent and deformed; the junction of ribs and thoracic vertebrae are invaginated to form rickets.
Diagnosis Based on symptoms, a preliminary diagnosis can be made, and further diagnosis requires feed testing and blood biochemical assays.
Control and adjust feed, supply calcium and phosphorus, supplement green grass, and apply calcium injection.
2.3.1 Rational preparation of waterfowl feed, the ratio of calcium and phosphorus is 2:1, the egg laying period is 5~6:1, and grass is supplemented.
2.3.2 Prevent and treat intestinal parasitic diseases, liver and kidney diseases, and eliminate unfavorable factors for vitamin D absorption and transformation.
2.3.3 During the rainy and egg-laying peak periods, the supply of calcium, phosphorus and vitamin D should be appropriately increased.
Add 10~20ml of cod liver oil per kilogram to the feed, and it will return to normal in 2~3 weeks. In severe cases, 1ml of vitriol-based calcium can be injected intramuscularly.
3 vitamin E and selenium deficiency
vitamin E and selenium deficiency, also known as white muscle disease. Deficiency of selenium and vitamin E causes the antioxidant function of the body to be impaired. Clinically, it is a nutritional and metabolic disease characterized by exudative diathesis, encephalomalacia and leukemia. It can occur in waterfowl of different breeds and ages, but it is more common in juvenile waterfowl aged 1 to 6 weeks.
3.1.1 The feed lacks feed rich in vitamin E, or the compound feed does not add vitamin E preparations. Vitamin E mainly exists in vegetable oil, grain germ and green feed, and also has a certain content in rice bran, barley and wheat, followed by soybean cake and fish meal, and is relatively lacking in corn and bran.
3.1.2 When the feed is stored or processed improperly, rancidity and deterioration occur, and vitamin E is destroyed in large quantities, vitamin E deficiency is prone to occur.
3.1.3 Coccidiosis and other chronic gastric and intestinal diseases can reduce the absorption and utilization rate of vitamin E and lead to deficiency.
3.1.4 There is an antagonistic effect between cadmium, mercury, copper, molybdenum and other metal elements in the environment and selenium, which can interfere with the absorption and utilization of selenium.
Adult waterfowl generally do not show obvious symptoms when they are deficient in vitamin E. Egg-laying birds continue to lay eggs, and the egg-laying rate is basically normal; male birds often have shrunk testicles, which are manifested as weak libido and sperm in the semen. The number of eggs is reduced, even without sperm; the fertilization rate and hatching rate of the eggs are reduced, and the embryos die more during hatching.
3.2.2 When the chicks are deficient in vitamin E, the three main types are encephalomalacia, exudative diathesis and white muscle disease.
is most common in young birds aged 15 to 30 days. Symptoms are motor ataxia, with the head bent back or down, sometimes to one side, and rhythmic spasms of the legs. Sometimes incomplete paralysis of the wings or legs occurs, and eventually it collapses and dies.
At necropsy, the main lesions were in the cerebellum, followed by the striatum, oblongata, and midbrain. The cerebellum develops softening and swelling, meninges edema, and small hemorrhages are common on the cerebellar surface. In severe cases, the entire cerebellum is softened and deformed, or even soft and unformed, and chylous fluid flows out during incision. The gyrus was flattened, and a necrotic area with yellow-green opacity was seen in the brain.
18.104.22.168 Exudative diathesis
mostly occurs in 20-30-day-old chicks, characterized by edema in the neck, chest and subcutaneous tissue (this is the result of increased permeability of the capillary wall, so it is called exudative). sexual qualities). In severe cases, the chest and abdomen will be swollen, purple-red or gray-green. Because of the accumulation of a large amount of fluid under the skin of the abdomen, the sick bird stands with its legs far apart. A large amount of light blue-green viscous fluid can be seen under the skin, which is caused by the presence of blood in the edema fluid. There is also a lot of fluid in the pericardium.
22.214.171.124 White muscle disease (muscular dystrophy)
mostly occurs in chicks around 4 weeks of age, lack of vitamin E, accompanied by a lack of sulfur-containing amino acids, muscular dystrophy can occur, characterized by grayish-white stripes in the chest muscles (hence the name white muscle disease). This is due to degeneration and coagulation necrosis of muscle fiber bundles. The lack of vitamin E in ducklings can cause muscular dystrophy in the skeletal muscles of the whole body (especially the muscles of the chest and legs). Muscles were pale and anemic, and pectoral and leg muscles also had grayish-white streaks. It is manifested as general weakness, ataxia, inability to stand, and can cause a large number of deaths.
It is generally believed that when a single vitamin E is deficient, encephalomalacia is the main disease; when vitamin E and selenium are deficient at the same time, exudative quality is predominant; and when vitamin E, selenium and sulfur-containing amino acids are deficient at the same time, leukemia main.
3.3 Prevention and control
3.3.1 Preventive measures
Vitamin E is abundant in fresh green fodder and green hay, as well as in seed germ and vegetable oil. Therefore, vitamin E deficiency generally does not occur when there is sufficient green fodder. However, vitamin E is easily destroyed by alkali, so feeding more green feeds and grains can prevent the disease.
In low selenium areas, sodium selenite should also be added to the feed, while preventing the feeding of moldy and rancid feeds.
3.3.2 For the treatment
of encephalomalacia in chicks, each chick was fed with vitamin E5IU daily, and the mild cases were effective once, and 3-4 days were used as a course of treatment. At the same time, 0.05-0.1 mg of sodium selenite should be added to the diet per kilogram.
For exudative diathesis and white muscle disease of young birds, vitamin E 20IU or 10g vegetable oil, 0.2mg sodium selenite, and 2~3g methionine were added to the diet per kilogram for 2~3 weeks.
When adult birds lack vitamin E, add vitamin E 10~20IU or 5g vegetable oil per kilogram of diet for 2~4 weeks, and feed green feed as appropriate.
4Vitamin B deficiency
Vitamin B1, also known as thiamine, can be rapidly destroyed by heat and alkali. Absorbed mainly in the duodenum, as a coenzyme involved in glucose metabolism and the tricarboxylic acid cycle, when the deficiency leads to the accumulation of pyruvate and lactate in the blood and tissues, resulting in neuroinflammation and myocarditis symptoms.
4.1 The cause
of primary vitamin B1 deficiency is mainly seen in poultry that are fed a diet lacking this vitamin for a long time, and the refined grains lack bran feed; the feed is processed in a neutral or alkaline environment, and it becomes moldy and deteriorated after long-term storage.
Ducks eat animal feeds such as small fish and shrimp during grazing. These animals contain thiamine enzymes that can decompose vitamin B1 and cause vitamin B1 deficiency.
When suffering from digestive tract diseases, the ability to absorb and synthesize vitamin B1 is reduced, resulting in a deficiency.
When vitamin B1 is deficient in the body, acetylcholine is rapidly decomposed, resulting in weakened gastrointestinal secretion and peristalsis, and indigestion symptoms appear. Sick waterfowl have poor appetite, haggard, indigestion and thinness. Polyneuritis caused by peripheral nerve damage: opisthotonus, sitting or lying down, see Figure 8, head pulled back, stargazing posture, rigidity and frequent spasms.
4.3 Prevention and control
4.3.1 The feed is formulated to ensure sufficient vitamin B1 content. It is not appropriate to store the feed for a long time, and it should be used up within 7 to 10 days.
4.3.2 When eating a large amount of fish and shrimp feed, supplement vitamin B1.
Add 10-20 mg of thiamine hydrochloride per kilogram of feed for 1-2 weeks. Or take it with vitamin B complex solution, 0.2~0.5ml each time, twice a day 5 Vitamin B2 deficiency
Vitamin B2 is also called riboflavin, animals lack the ability to store riboflavin, which is involved in carbohydrates, Metabolism of fat and protein. The requirement of riboflavin in birds increases with the increase of the ambient temperature, and the requirement can be doubled if the ambient temperature differs by 25℃. Requirement: 2~4mg per kilogram of diet.
Slow growth, weakness, and weight loss in the absence of symptoms, but good appetite, diarrhea at 1 to 2 weeks of age, inward bending of the feet, see Figure 9, hock walking, paralysis of the legs, decreased egg production and hatchability. The disease is diagnosed by observing whether the symptoms are relieved after riboflavin supplementation.
There should be sufficient yeast, fish meal, bran, etc. in the control feed. Storage environment should avoid hot and alkaline environment. Injection or oral VB2 preparations after onset.