Pig's mineral feed and its nutritional characteristics
Mineral feeds include mineral feeds that provide major elements such as calcium and phosphorus, and inorganic salts that provide trace elements such as iron, copper, manganese, zinc, and selenium. (l) Calcium source feed The calcium content of the natural plant feed is insufficient compared to the calcium requirement of the animal. Therefore, calcium source feed must be added to the diet. Stone powder is a product of comprehensive exploitation of limestone and marble. The basic ingredient is calcium carbonate, which contains 34% to 38% of calcium. It is the cheapest source of calcium. Shell powder shells are shells of seawater and freshwater mollusks. The main component of the shell is also calcium carbonate. The amount of calcium is similar to stone powder. Fresh shells must be heated and crushed to prevent transmission of disease. The dead shell's shell organic matter has been decomposed and safer. Shells are often mixed with fine sand and mud. Shell powder containing these impurities contains low amounts of calcium. (2) Phosphorus sources, phosphorus, and calcium sources The source of mineral feeds for providing provenance is limited to phosphoric acid, sodium phosphate, etc. Phosphoric acid is liquid and corrosive. It is inconvenient to use compound feed for production. Sodium phosphate provides both phosphorus and sodium. Most of the commonly used calcium and phosphorus feeds contain both calcium and phosphorus. The bone meal is dried and crushed by animal bones after hot pressing, degreasing and degumming. The basic composition is calcium phosphate. High quality bone meal contains 28% calcium and 13.1% phosphorus. The ratio of calcium to phosphorus is 2:1. It is a balance between calcium and phosphorus. Mineral feed. The simple method of producing bone meal is directly crushed without degreasing, degumming, and autoclaving. There are many fats and proteins in the product, which are prone to spoilage and deterioration. There are also risks of transmission of disease, and care should be taken when using it. Calcium hydrogen phosphate without crystal water contains 29.46% of calcium phosphate and 22.77% of phosphorus. 2 Crystalline water contains 23.29% of calcium phosphate and 18.01% of phosphorus. Calcium and phosphorus in calcium hydrogen phosphate are easily absorbed by animals. Is the most commonly used calcium phosphate feed. In addition, calcium phosphate and superphosphate are calcium- and phosphorus-rich feeds, but their absorption rate is not as high as calcium hydrogen phosphate. (3) Salt The main component of salt is sodium chloride, which can provide two kinds of sodium and chlorine, which are relatively lack of plant feed. At the same time, it has a flavoring effect and can enhance animal appetite. (4) Trace Element Additives According to the required amount of trace elements in animals, trace mineral additives or traces of trace elements may be used to prepare trace element additives to supplement the deficiency of trace elements in feed. At present, there are many kinds of trace element additives. When using them, it is necessary to carefully identify the quality and to pay attention to the content of trace elements in different compounds.
Ventilator block diagram Medical Positive Pressure Breathing Machine Positive Pressure Breathing Machine,Continuous Positive Pressure Ventilation,Intermittent Positive Pressure Ventilation,Intermittent Positive Pressure Breathing Machine Guangzhou Zhongzhinan Supply Chain Co.,Ltd. , https://www.gzzhongzhinan.com
One. Main mechanical ventilation modes
(1) Intermittent Positive Pressure Ventilation (IPPV): positive pressure in the inspiratory phase and zero pressure in the expiratory phase. 1. Working principle: The ventilator generates positive pressure in the inspiratory phase and presses the gas into the lungs. After the pressure rises to a certain level or the inhaled volume reaches a certain level, the ventilator stops supplying air, the exhalation valve opens, and the patient's thorax Passive collapse of the lungs and exhalation. 2. Clinical application: Various patients with respiratory failure mainly based on ventilation function, such as COPD.
(2) Intermittent positive and negative pressure ventilation (IPNPV): the inspiratory phase is positive pressure and the expiratory phase is negative pressure. 1. How it works: The ventilator works both in the inspiratory and exhaled phases. 2. Clinical application: Expiratory negative pressure can cause alveolar collapse and cause iatrogenic atelectasis.
(3) Continuous positive pressure airway ventilation (CPAP): Refers to the patient's spontaneous breathing and artificial positive airway pressure during the entire respiratory cycle. 1. Working principle: Inspiratory phase gives continuous positive pressure air flow, and exhalation phase also gives a certain resistance, so that the airway pressure of inhalation and exhalation phases are higher than atmospheric pressure. 2. Advantages: The continuous positive pressure airflow during inhalation is greater than the inspiratory airflow, which saves the patient's inhalation effort, increases FRC, and prevents the collapse of the airway and alveoli. Can be used for exercise before going offline. 3. Disadvantages: great interference to circulation, large pressure injury of lung tissue.
(4) Intermittent command ventilation and synchronized intermittent command ventilation (IMV / SIMV) IMV: There is no synchronization device, the ventilator air supply does not require the patient's spontaneous breathing trigger, and the time of each air supply in the breathing cycle is not constant. 2. SIMV: There is a synchronization device. The ventilator gives the patient a commanded breath according to the pre-designed breathing parameters every minute. The patient can breathe spontaneously without being affected by the ventilator. 3. Advantages: It exerts its ability to regulate breathing while offline; it has less influence on circulation and lungs than IPPV; it reduces the use of shock medicine to a certain extent. 4. Application: It is generally considered to be used when off-line. When R <5 times / min, it still maintains a good oxygenation state. You can consider off-line. Generally, PSV is added to avoid respiratory muscle fatigue.
(5) Mandatory ventilation per minute (MMV) When spontaneous breathing> preset minute ventilation, the ventilator does not command ventilation, but only provides a continuous positive pressure. 2. When spontaneous breathing is less than the preset minute ventilation volume, the ventilator performs command ventilation to increase the minute ventilation volume to reach the preset level.
(6) Pressure Support Ventilation (PSV) Definition: Under the prerequisite of spontaneous breathing, each inhalation receives a certain level of pressure support, increasing the patient's inhalation depth and inhalation volume. 2. How it works: The inspiratory pressure begins with the patient's inspiratory action, and ends when the inspiratory flow rate decreases to a certain level or the patient attempts to exhale hard. Compared with IPPV, the pressure it supports is constant, and it is adjusted by the feedback of the inspiratory flow rate. Compared with SIMV, it can get pressure support for each inhalation, but the level of support can be set according to different needs. 3. Application: SIMV + PSV: used for preparation before off-line, can reduce breathing work and oxygen consumption Indications: Exercise the ventilator; prepare before going offline; the ventilator is weak due to various reasons; severe flail chest causes abnormal breathing. 5. Note: Generally not used alone, it will produce insufficient or excessive ventilation.
(7) Volume Supported Ventilation (VSV): Each breath is triggered by the patient's spontaneous breathing. The patient can also breathe without any support and can reach the expected TV and MV levels. The ventilator will allow the patient to be truly autonomous Breathing also applies to preparations before going offline.
(8) Capacity control of pressure regulation
(IX) Biphasic or bilevel positive pressure ventilation How it works: P1 is equivalent to inspiratory pressure, P2 is equivalent to breathing pressure, T1 is equivalent to inspiratory time, and T2 is equivalent to exhalation time. 2. Clinical application: (1) When P1 = inspiratory pressure, T1 = inspiratory time, P2 = 0 or PEEP, T2 = expiratory time, which is equivalent to IPPV. (2) When P1 = PEEP, T1 = infinity, P2 = 0, T2 = O, which is equivalent to CPAP. (3) When P1 = inspiratory pressure, T1 = inspiratory time, P2-0 or PEEP, T2 = desired controlled inhalation cycle, equivalent to SIMV.