1. Factors affecting drugs include dose, dosage form, route of administration, course of treatment, combination of drugs, etc. Animal aspects include species differences, physiological differences, pathological factors, individual differences, feeding management, and environmental factors.
2. Penicillin can bind to the penicillin-binding protein of the bacterial cytoplasmic membrane, causing the loss of transpeptidase and endopeptidase activities, resulting in the blockage of the cross-association of mucopeptides of sensitive bacteria and the defect of the cell wall, thus causing the death of bacteria.
3. Antiasthmatic drugs refer to a class of drugs that relieve bronchial smooth muscle spasm and dilate bronchial tubes, such as aminophylline, which mainly has a strong relaxing effect on bronchial smooth muscle, and is commonly used to relieve the symptoms of bronchial asthma in livestock, and can also be used for cardiac insufficiency or pulmonary edema.
4. Mammary gland secretory cells take nutrients from the blood and synthesize lactose, milk fat and milk protein. Lactose is made of glucose and galactose, glucose in breast cells ** in the blood, most of the galactose is converted from glucose, lactose is the main factor in maintaining osmotic pressure in milk, so lactation is closely related to lactose concentration, sudden change of feed will cause stress, decreased feed intake, and reduced lactose synthesis.
5. African swine fever is a virulent infectious disease of pigs caused by African swine fever virus, which can spread rapidly and cause a high mortality rate, which is characterized by reddening, necrotizing dermatitis, and severe bleeding of internal organs, and can manifest acute, subacute, chronic, and **infection in the course of the disease. African swine fever virus is the only DNA arbovirus discovered so far. Only infected pigs, including wild boars and domestic pigs, are the protective reservoir and vector of ticks.
6. Mycotoxin poisoning mainly causes stem cell degeneration, necrosis, bleeding, bile duct and hepatocyte proliferation, clinically characterized by systemic hemorrhage, digestive disorders, ascites, jaundice, and neurological symptoms, and damp heat is the main environmental factor leading to feed mildew.
7. Porcine lung disease (pasteurella): extreme difficulty in breathing, increased body temperature;Acute death, high case fatality rate. Autopsy revealed lobar pneumonia and lung abscess;Intestinal inflammation is evident. Pasteurella Switzerland stains in the shape of a bilical rod with a strong pole, and gram-negative bacteria are sensitive to streptomycin, causing lobar pneumonia and hemorrhagic inflammation of the intestines.
Mycoplasma infection can cause lobar pneumonia, and pleural effusions after autopsy quickly coagulate into jelly when exposed to air.
8. Pseudorabies: is an acute infectious disease of pigs caused by porcine pseudorabies virus, which can cause abortion, stillbirth, etc., the onset of pigs shows obvious neurological symptoms, necropsy shows that the kidneys have needle-sized bleeding points, sometimes pulmonary edema, meningeal surface congestion, hemorrhage, and gray necrotic lesions in the organs. The laboratory method for confirming wild virus infection is whole-virus GE-ELISA.
9. Yellow dysentery in piglets: yellow loose feces, intestinal distention, containing yellow contents and gases, and acute catarrhal inflammatory changes in the intestinal mucosa, especially the duodenum. Porcine colibacillosis presents with a white dysentery type at the age of 10-30 days, excreting gray-white or milky pasty, pasty feces. After 30 days of age, the internal edema type is manifested, mostly occurring in healthy and fast-growing piglets, edema is a special symptom of E. coliformosis, which is common in the face, eyelids, etc. Isolation and identification of pathogens are commonly used in the diagnosis of the disease.
10. Prevention and control of PRRS:
1. Improve the biosecurity system.
The biosecurity system of pig farms is a multi-layered barrier to prevent the invasion of pathogens, and has become an important means of disease prevention and control. Biosecurity is not just about disinfection, it is not the same as disinfection. The perfect biosecurity system is a very complex multidisciplinary system engineering, starting from the planning and construction of the pig farm, throughout all aspects of the production and operation management of the pig farm, the main task is to achieve effective control of the "four flows" (i.e., pig flow, vehicle flow, logistics) and biological media related to production and operation management. Select the site, build and manage the decontamination center, transit area, staff kitchen, and control people, vehicles, objects, pigs and other animals, etc., so as to prevent PRRSV from entering the farmAir filtration system (according to the actual assessment of the pig farm), one-way flow, partition management, isolation and disinfection between various areas, after all the nursery pigs are cleared, the barn is thoroughly cleaned, disinfected and left vacant for more than 1 week, and the stillborn and afterborn are treated harmlessly in a timely manner, and the weak, disabled, secondary, stiff, and sick pigs are decisively disposed of to reduce the viral load in the environment and reduce or avoid bringing the virus in the positive environment to the negative environment. Biosecurity needs to have a well-developed system and must be implemented in place.
In reality, there are four main types of biosecurity imperfections:
First, biosecurity measures are too cumbersome, and employees are resistant to them, making it difficult to implement them in place
Second, the biosecurity system is not perfect, there are many loopholes, and there are many opportunities for viruses to take advantage of
The third is that there is no assessment, just "done", how well it is done, I don't know;
Fourth, a biosecurity system has been established, but it has not been implemented due to various reasons. Pig farms need to establish a scientific supervision, assessment and incentive mechanism to ensure the strong execution of pig farm employees, and regularly review and continuously improve the biosecurity system.
2. Scientific feeding management.
PRSV is also a conditional pathogen. Therefore, the concept of PRRS prevention and control should be changed from the past elimination of pathogens, reliance on vaccines and drugs, and neglect of the health and disease resistance of the pig herd to enhance the quality of the pig herd and control the pathogen. The prevention and control of PRRS in feeding management is mainly to reduce or avoid various environmental stresses and production stresses, control feeding density, provide clean, nutritious and comprehensive diets and clean, sufficient, and suitable temperature drinking water. In addition to strengthening routine feeding management, special attention is paid to anti-stress management and environmental management.