Thoughts on the Development trend of Egg (Meat) Chicken Diseases

At present, with the scale and intensification of breeding, poultry diseases gradually tend to be younger and more complicated, especially the development of egg (meat) chicken diseases is becoming more and more complicated. once the disease occurs, it is difficult to eradicate and greatly reduce the economic benefits. now the new characteristics of disease epidemic in the production process of egg (meat) chicken are summarized as follows, which can be used as a reference for the majority of breeding friends.

First, tend to develop at a younger age

Early onset: especially meat birds appear respiratory symptoms at the age of 3-5 days, characterized by slight nose swinging and coughing, especially after the first immunization with small triple vaccine, which aggravates respiratory symptoms due to immune response and stress stimulation to the respiratory tract. Some chickens broke out of Newcastle disease at the age of 6 days before they had time to make the Newcastle vaccine, and some were earlier, with typical symptoms, and with untimely treatment, the mortality rate increased day by day; some 7-9-day-old outbreak of bursitis, accompanied by respiratory tract, enteritis symptoms, as the body just got out of the protection of maternal antibodies, did not have time for immunity, the treatment is very difficult, the mortality rate is often very high, even if the cure is very disadvantageous to the later growth.

Inseparable from the quality of breeder chickens: due to unscientific breeding, unreasonable disease treatment and drug abuse, breeder chickens have a disease or even several diseases for life, especially infection with mycoplasma, Escherichia coli, renal branch, leukemia and other effects on breeder eggs can be imagined, hatched chicks are infected with bacteria and virus, and their growth and development in the later stage is not optimistic, so it is recommended that the majority of farmers must enter the chicken from the SPF breeding farm.

Second, the analysis of the reasons for the complication.

1. The disinfection of the inside and outside of the chicken house and the utensils is not strict, and the randomness is very strong: after a batch of chickens are out of the pen, the henhouse is empty for at least two weeks, remove all items inside and outside the house that have nothing to do with brooding, wash the walls and floors, repair doors and windows and spray disinfectant. In the first five days of brooding, drinking fountains, buckets and other supplies should be placed in the house, and the doors and windows should be fumigated with formaldehyde (formaldehyde 42ml per cubic meter, 21 grams of potassium permanganate). After being sealed for 24 hours, open the doors and windows for 24 hours. And now farmers map convenience with little effort, with some manufacturers produced "smoke bombs" instead of formaldehyde fumigation disinfection, disinfection is routine for them, there is such a thing, anyway, there is no immediate effect, some farmers simply use one or two kinds of disinfectant spray disinfection. Due to the weak concept of disinfection, there are patients in the chicken coop for a long time, and the germs multiply to a certain extent, which makes the chicks get sick very early and it is difficult to eradicate.

2. The immunity is not scientific and the method is not standard.

For example, the first immunity of bursitis of Fabricius is often fine, which causes mental depression in large groups of chickens, obvious respiratory and intestinal symptoms, accompanied by death. During this period, a large number of anti-intestinal and respiratory infection drugs are used, and the effects are different. During this period, the mortality rate began to rise. Considering that the chickens were in the incubation period of bursal disease at that time, immunity caused the body's resistance to be low, and the source of the disease occurred through respiratory tract infection at any time, and a series of symptoms appeared, precisely because the immunity was low in the incubation period. the effect of immune bursa vaccine is very bad, but it causes respiratory and intestinal symptoms to be more serious after immunization. at this time, the immune organ of bursa of Fabricius has come on, so a series of symptoms appear immediately. At this time, the effects of all kinds of Chinese and western medicine on respiratory tract, intestinal tract and anti-bursal disease are not significant; the first drop-free mouth of bursa of Fabricius is a scientific way of immunity, but in reality, people often use drinking water for the first time to save trouble. the result is also one of the reasons for the above situation. What is even more ridiculous is that the fowlpox vaccine is vaccinated not by thorns but by drinking water, which is often vaccinated at the same time as Ⅰ, while Ⅰ does not use injection but drinking water, which is a serious violation of science. Infectious laryngitis vaccine is one of the most harmful vaccines for the majority of farmers. Wiping the anus or eye drops is the most desirable method, but people are afraid of the stress caused by immunity, but they are immunized with drinking water. Some farmers use the method of wiping the anus, but the operation is seriously wrong. It is not wiped into the anus at all, and the due immune effect is not achieved, so it is difficult to cure in the event of an outbreak in the later stage. Because the antibody level of Newcastle disease is low or uneven after the peak of laying, commercial laying hens need to be immunized with Newcastle disease vaccine every certain period of time. Generally, they are immunized with Ⅰ, Ⅳ or co-30. In theory, the most reasonable way to use Ⅰ is intramuscular injection, but in reality, people often use drinking water, and the dose is frightening. Ⅰ is 5-6 times the amount of drinking water every other month. The correct way to add immunity to Newcastle disease in commercial laying hens after the laying peak should be: alternately immunized with Ⅳ or co-30 drinking water and spray every other month or two months, the immune dose depends on the local situation, why adopt the alternative immunization of Ⅳ line, co-30 drinking water and spray, the reason is that the digestive system is most easily absorbed by drinking water immunity, and the protection rate to respiratory system is almost zero. Ⅳ can improve the antibody level of Newcastle disease, while co-30 can make the antibody level neat. The alternate use of the two can improve the antibody level on the basis of neatness, so as to achieve the purpose of disease prevention. In addition, when immunization is injected intramuscularly or subcutaneously, needles should be changed to avoid the unscientific and irrational practice of hitting the whole group with one needle.

3. The effect of nutrition level on the prevention and treatment of poultry diseases.

For a long time, people often only pay attention to the effect of nutrition level (protein, fat, vitamins, minerals, etc.) on poultry production performance, but ignore its role in disease prevention. In recent years, research in this area has become the focus of animal science research. Preliminary studies at home and abroad have shown that lack or excess of nutrition will lead to poultry immune failure, increase in morbidity, thus affecting the rate of return on breeding investment.

For example, chicken chicks are prone to infectious renal transmission in the early stage, and the ways of mitigation are as follows: one is to increase the temperature by 1-2 ℃; the second is to reduce the level of protein in feeding, which can be used to add chopped corn in feed; the third is symptomatic treatment and adding drugs. If we do not pay attention to the effect of nutrition level on the prevention and treatment of chicken diseases, blindly increase the amount of drug treatment and ignore it, because the use of large doses of drugs increases the burden on the kidney and fails to improve the metabolic balance of the body in time, the disease becomes more and more serious, and finally there is mortality, delaying the best period of treatment. There are chicken outbreaks of gout, in drug treatment at the same time must pay attention to reduce the protein in the feed. When chickens suffer from respiratory and intestinal diseases, they must pay attention to the supplement of vitamins to make up for the loss of the body.

4. There are many factors affecting the outbreak of poultry diseases, among which the level of feeding and management (temperature, humidity, feeding density and the content of harmful gases produced by metabolism, etc.) is a daily work that can not be ignored. The most inconspicuous and most important task in daily work is the cleaning of feces, which often fails to attract people's attention. in theory, it should be one day to remove feces and one day to disinfect, but in reality, very few people do this. It gives the disease a great opportunity to get in. Most farmers clear their feces once a week to half a month, but in winter it is better that in summer, because the chickens drink a lot of water, the feces are very thin, the humidity of the chicken coop can be imagined, and the smell is unpleasant and full of flies. Harmful gases, especially the inner stove in the chicken house in winter, can not be well combined with ventilation and warmth, resulting in a strong ammonia smell in the chicken house and a poor feeding environment. For broiler chicks raised with padding, farmers are greedy for cheap bedding not one batch after another, but one batch after another, so that the source of the disease can not be effectively killed, but survive in the chicken coop for a long time, and the opportunity is mature to make the chickens get sick again. This is also one of the reasons why it is difficult to eradicate coccidiosis by feeding coccidiosis.

III. Thoughts on current disease prevention and treatment

1. Understanding of respiratory diseases

At present, there are two kinds of infected mycoplasma disease that are difficult to eradicate, one is vertical transmission, the other is vaccine contamination. If the above opening drugs targeted selection or immunization after the use of special drugs to prevent respiratory tract infection, the therapeutic effect is relatively accurate. Infectious rhinitis is also an infectious disease which is stubborn and difficult to eradicate, and its recurrence rate is very high, which has a lot to do with the poor environment of the chicken house. It is suggested that the drugs combined with the treatment of colibacillosis should be used in the treatment of respiratory diseases, because the concentration of the drugs in the airbag is very low, it is best to use aerosol administration in the treatment of pneumonitis, because aerosol administration can be achieved directly through the respiratory tract and act on the surface of the airbag; it can also be administered through intramuscular injection to rapidly increase the drug concentration in the blood and act on the airbag quickly. Large groups adopt the treatment method of combination of traditional Chinese and western medicine, and traditional Chinese medicine uses drugs to relieve cough, resolve phlegm, relieve asthma and improve immunity. In addition, cod liver oil has a strong repairing effect on respiratory tract mucosa, and the adjuvant treatment of respiratory diseases can not be ignored.

2. Understanding of Escherichia coli in chickens.

There are two reasons for E. coli infection in chickens: one is vertical transmission, the other is cross-infection. For the first group, 33-34 ℃ is the best temperature value for yolk absorption by raising the temperature, and then regular drug prevention. In view of the second type, through the combination of environmental disinfection inside and outside the chicken house, drinking water disinfection and spray disinfection, we should pay attention to the prevention of drugs, and note that the use of high-sensitive antibiotics during the prevention period, once implemented, the effect was very significant at that time, and when the disease broke out in the later stage, it is even more difficult to cure.

3. The choice of vaccine is very important

We should choose regular brand products, preferably SPF vaccine, and reasonably and scientifically choose to use combined vaccine or single vaccine according to the epidemic situation of local diseases, adopt the correct vaccination method and immune dose, consult the technicians of the vaccine factory, the best dose and time to use the vaccine, and do not blindly increase or reduce the dose. Third, we should pay attention to the drug filling in the immune blank period, which can not only prevent the virus invasion in the immune blank period, but also improve the body immunity and antibody titer and reduce the immune response.