What are the common diseases in laying duck farming? How to prevent and treat them

The key to laying duck farming lies in the prevention and treatment of laying duck diseases, so the vast number of laying duck farmers must figure out what diseases laying ducks have. Only by mastering the characteristics of some of its diseases and the treatment methods, and by prescribing the right medicine in the daily farming process, can its production be increased.

What diseases do laying ducks have

1. Duck influenza

1. Symptoms. Acute septicemic type: sudden onset, sudden death. With a slightly longer course, cases show a drooping head and shrunken neck, deep lethargy, ruffled feathers, elevated body temperature, reduced or lost appetite, drinking only water, passing white or pale yellow watery diarrhea, and weak, limp legs. After laying ducks are infected, egg production drops rapidly within a few days, and may even stop; acute respiratory type: subcutaneous edema of the head or face, tearing and runny nose, watery diarrhea, high morbidity, low mortality, and a marked drop in egg production and hatchability.

2. Prevention and treatment. Carry out immunization properly; generally the first vaccination is given at 15-20 days of age, the second 2 months later, and another immunization before laying, which can achieve control of the outbreak of this disease.

Once this disease occurs, the epidemic point and area should be immediately blocked off, diseased birds culled and subjected to harmless disposal, the site and equipment thoroughly disinfected, and emergency vaccination of the unaffected duck flock with antiserum or yolk antibody has a certain protective effect.

2. Duck plague (commonly known as “big-head plague”)

1. Symptoms. At the beginning of the disease, body temperature suddenly rises to 43-44°C; sick ducks are listless, with a shrunken neck, loss of appetite, increased thirst, and weak legs. Sick ducks are unwilling to enter water, have moist eyes with tearing, and some have purulent discharge. The nasal cavity discharges serous fluid, breathing is difficult, and moist rales are often present. Some sick ducks have swelling of the head and neck, forming a “big-head duck”. Sick ducks excrete green or grayish-white diarrhea. In severe cases, sick ducks die in 2-3 days, generally not exceeding 10 days, and the whole epidemic process lasts 2-6 weeks.

2. Prevention and treatment. Once this disease is found, isolate immediately and thoroughly disinfect the duck flock and site. For early treatment, use anti-duck-plague hyperimmune serum, injecting 0.5 ml intramuscularly per duck; polycytosine (an endogenous interferon) can also be used, injecting 1 ml intramuscularly per adult duck, once every 3 days, for 2-3 consecutive times.

3. Duck viral hepatitis  

1. Symptoms. The incubation period is 1-4 days. Some ducklings often die suddenly without any symptoms when the disease occurs, and within a few hours the whole flock is affected. Sick ducks are listless, stand still and doze, and completely lose appetite; some cases develop diarrhea, after which neurological symptoms appear, with uncoordinated movement, the body tilting to one side, the head tilted back, the back touching the ground, circling and squatting, and spasmodic kicking of both feet, assuming an opisthotonus posture, hence it is also called “back-neck disease”.

2. Prevention and treatment. Specific hyperimmune serum or hyperimmune yolk fluid can be used to treat and prevent this disease. Once this disease is found, immediately inject antiserum, 0.5 ml intramuscularly per duckling, which can stop the spread of the epidemic and reduce deaths, with a protection rate of 90%-100%. Use duckling viral hepatitis attenuated vaccine or inactivated vaccine, immunizing each mother duck twice, 1 ml each time, with an interval of 14 days. Ducklings hatched from eggs laid by immunized mother ducks can, through passive immunity, remain free of this disease for 2-3 weeks.

4. Duck cholera  

1. Symptoms. The main features of sick ducks are passing green diarrhea, small bleeding points on the serosa, and the liver covered with grayish-yellow punctate necrotic spots. This disease has a sudden onset and rapid death.

2. Prevention and treatment. At present, the poultry cholera vaccines produced in China are of two kinds: one is attenuated vaccine; the other is oil-emulsion inactivated bacterin, which can be vaccinated regularly. Treatment mostly uses a two-pronged approach of intramuscular injection and medicated feed. Use penicillin sodium 800,000 IU, diluted with compound aminopyrine solution, injecting 10,000-20,000 IU intramuscularly per duck, once a day for 2 consecutive days, while adding 40-50 g of oxytetracycline per 50 kg of feed for feeding, for 5-7 consecutive days; or, in cases of secondary infection by Gram-negative bacteria, dissolve penicillin sodium 800,000 IU per bottle and streptomycin 1,000,000 IU in normal saline to treat 40-80 sick ducks, with 0.5-1 ml intramuscularly per duck, once a day for 2 consecutive days, while feeding oxytetracycline for 5-7 days.

5. Duck colibacillosis

1. Symptoms. Newly hatched ducklings, after becoming ill, are weak in constitution, with closed eyes and a shrunken neck, a relatively large abdominal girth, and often diarrhea, mostly dying from septicemia. Older ducklings show listlessness, no appetite, standing still with a shrunken neck and lethargy, thick sticky discharge from both eyes and nostrils, passing grayish-green diarrhea, panting, and weakness, often dying from septicemia and dehydration. Sick adult ducks show a preference for lying down and unwillingness to move; when standing, the abdomen can be seen enlarged and sagging, in a penguin-like posture, with a fluid wave felt on hand pressure and ascites flowing out on puncture.

2. Prevention and treatment. Prevention: pay attention to disinfection of tools and equipment, regularly disinfect the duck house, and regularly add antibiotics to drinking water and feed; treatment: antibiotics are effective against this disease. Since bacteria in the general intestinal tract readily develop drug resistance, a drug sensitivity test is needed to select sensitive drugs. For example, use norfloxacin mixed into feed at 0.01% for feeding, for 3 consecutive days.

6. Coccidiosis

1. Symptoms. Coccidiosis is an acute disease that seriously harms ducks, characterized by bloody feces. Morbidity is high, growth is stunted, and weight gain is slow. Acute cases mostly occur in ducklings, especially ducks 2-3 weeks of age. Usually 3 days after infection, symptoms such as chilling, a shrunken neck, no eating, great thirst, and a preference for lying down appear, with dark red or deep purple bloody stool, and acute death often occurs.

2. Prevention and treatment. Prevent insects from entering the duck house and kill vector insects around the duck house. For drug prevention, sulfadimethoxine 25-73 mg/kg or compound sulfaquinoxaline 200 mg/kg can be mixed into feed for feeding. For treatment, sulfadimethoxine 500 mg/L in drinking water for 3-7 days can be chosen, then 300 mg/L in drinking water for 2 days; sulfadimethoxine 400 mg/kg and pyrimethamine 4 mg/kg mixed into feed, used for 1 week, then switched to a preventive dose; compound sulfaquinoxaline 200 mg/kg mixed into feed continuously; to prevent drug poisoning, use it first for 5 days, stop for 2-3 days, then use again. Note to change drugs in good time to avoid causing drug resistance.

Four tips for disease prevention and treatment in laying ducks

1. Look at body weight: if the flock's laying rate is above 80% and the ducks' body weight shows a slight downward trend, animal feed should be appropriately increased; if the ducks' body weight increases and the body also shows a tendency to fatten, but the laying rate is still 80%, roughage and green feed can be appropriately increased, or feed intake can be controlled so the ducks do not eat too much concentrated feed, but animal protein feed should still be maintained at the original level or slightly increased; if body weight is normal and the laying rate is also relatively high, the protein level in the feed should be slightly increased compared with the previous stage; when the laying rate drops to 60% and is difficult to bring back up, there is no need to add feed.

2. Look at feces: if the ducks' feces are thick, large, loose, in strips, with a glossy surface, and can be divided into several segments after being lightly stirred with a foot, it indicates that the combination of concentrated, rough, and green feed is reasonable; if the feces are small, fine, and firm, black in color, and the cross-section after stirring is granular, it indicates that the amount of concentrated feed is too much and the amount of green feed is too little, and digestion and absorption are abnormal, so the amount of concentrated feed should be reduced and green feed increased; if the feces are light in color and unformed, scattering as soon as they are passed, it indicates that the concentrated feed is insufficient and the nutritional level is on the low side, so concentrated feed should be supplemented; if the feces are yellow-white or grayish-green with a foul odor, it indicates that the ducks are sick and should be isolated for treatment.

3. Look at egg production: if the eggs are abnormal in shape and small, it indicates insufficient nutrition, and feeds rich in protein such as soybean cake, peanut cake, and fish meal must be added, raising the crude protein content in the daily ration to 20%, and appropriately increasing the total amount of the daily ration; if the eggshells become thin and translucent, with sand holes, rough or soft shells, it indicates that the feed quality is poor, especially insufficient calcium or lack of vitamin D, and feeds rich in minerals such as bone meal, shell powder, and lime powder and rich in vitamin D should be added; if egg weight decreases, cod liver oil and inorganic salt additives can be increased; if egg laying time is concentrated at 2 a.m., it indicates that feeding is appropriate; if egg laying is delayed each day and the eggs become smaller, then feed should be increased.

4. Look at vitality: healthy ducks with a high laying rate are full of energy and can stay submerged for a long time; after coming ashore, their feathers are smooth and not wet, and water droplets splash in all directions when they shake their feathers. If ducks are listless, move weakly, are afraid to enter water after being let out, and their feathers get wet or they even sink after entering water, it indicates that their daily ration is nutritionally insufficient, and animal-based fresh feed should be added in good time, along with sufficient cod liver oil, preferably clear cod liver oil, mixed into powder feed and fed at 1 ml per duck per day, fed for 3 days and stopped for 7 days as one course of treatment; alternatively, feed 0.5 ml per duck per day for 10 consecutive days.

Brooding techniques for laying ducks  

1. Select healthy ducklings: select ducklings that hatch on time, have a well-healed umbilical ring, a robust constitution, are lively and active, have bulging and spirited eyes, have no bloodstains or scabs, and are uniform in size.  

2. Pay attention to releasing into water: “releasing into water” is also called “testing water” and “dipping water”. Note that they must be released into water before first feeding, otherwise death is easily caused. The time for releasing into water is before first feeding on the 2nd day. The method of releasing into water is: on a sunny day with a temperature above 14°C, they can be released directly into cold water. If it rains, they can be released into water inside the duck house, using a basin of shallow water, just enough to soak over the insteps. After 2 days, the ducks can be allowed to enter water freely.  

3. Timely first feeding: first feeding is the first time feed is given. Note not to feed within 24 hours, to facilitate absorption of the yolk in the abdomen. After releasing into water, cooked rice mixed with 10% chopped bitter lettuce can be used for first feeding.  

4. Feeding frequency: from 1-7 days, feed 6 times a day, 4 times during the day and 2 times at night. From 7-21 days, feed 5 times a day. From 21-28 days, the number of times can be reduced further. When feeding, they should be divided into batches and groups, with 250 birds per group being suitable. The feeding principle is from fine to coarse, from cooked to raw, from soft to hard, from less to more, achieving fixed quantity, fixed amount, fixed quality, and fewer meals with more feeding, to avoid waste.  

5. Introduce meat as early as possible: introducing meat as early as possible means feeding animal feed as early as possible. As the saying goes, “geese need green, ducks need fishy”; on the 3rd day, animal feed can be given at a ratio of 10%-20%, choosing river snails, small fish and shrimp, earthworms, silkworm pupae, freshwater mussels, etc. Animal feed is required to be fresh and clean, chopped and mashed, and compound feed containing fish meal can also be used for feeding.  

6. Keep warm and prevent crushing: the brooding temperature for ducklings must be maintained uniformly, and “temperature according to the ducks” should be applied based on the ducklings' state of vitality combined with changes in outside air temperature. Generally, the temperature requirement is 32°C on the 1st day, 31-28°C from 2-7 days, 28-25°C from 8-14 days, and maintained at 25-20°C after 15 days. Special attention should be paid to keeping warm on rainy days and at night, while also ensuring good air circulation, dryness, and no draft, to prevent suffocation and freezing to death.  

7. Reasonable grouping: each group of ducklings should not exceed 300-500 birds, with 25-30 birds/sq m from 1-7 days, 20-25 birds/sq m from 7-14 days, and 15-20 birds/sq m from 15-28 days. Group them in good time according to the above requirements and strengthen group management.

Laying ducks are now raised by many people in rural areas, and the profits from laying ducks are very considerable, but in raising laying ducks, besides paying attention to their egg production, even more attention should be paid to the prevention of their diseases, giving timely treatment according to their symptoms.