Proper Methods for Processing and Storing Pig Feed

  Using appropriate methods to process and prepare feed can increase pigs' feed intake and improve the digestion and absorption of nutrients.

  I. Selection of Feed Ingredients

  A complete feed formula alone does not guarantee a nutritionally balanced, good feed. No matter how balanced the nutrition in the formula is, if problems arise with the ingredients or storage, all the effort is wasted. When considering ingredients for formulating diets, farmers often only pay attention to low-priced, easily obtainable materials while neglecting other unfavorable factors. The following issues should be noted when using ingredients:

  (1) Pay attention to ingredient quality. No matter how balanced the nutrients in a diet formula are, if adulterated feed is used, the formula loses its original value, and the conversion rate of the feed in the body will inevitably decline.

  Ingredients that may currently be adulterated include: fish meal adulterated with hydrolyzed feather meal and leather meal, urea, spoiled fish, cottonseed meal, etc., which lowers protein quality or leaves residual heavy metals and toxins; defatted rice bran adulterated with rice husk, sawdust, urea, etc., which worsens palatability and reduces feed quality; yeast powder adulterated with soybean flour, or soybean cake adulterated with soybean hulls, yellow corn flour, or soybean flour adulterated with stone powder and corn flour, etc., which reduces protein content; corn flour adulterated with corn cobs, miscellaneous grain flour adulterated with clay powder or stone powder, mineral additives adulterated with clay powder, meat and bone meal adulterated with feather meal or urea, etc., all of which result in insufficient content or failure to meet specifications. Therefore, when purchasing ingredients, be sure to identify whether they are genuine; ingredients that do not meet requirements must not be used even if the price is low.

  (2) Ingredients of unstable quality. Some ingredients do not decline in quality because of adulteration, but rather because improper processing methods increase their impurity content and make their nutrient composition unstable; or because different varieties and production areas cause great fluctuations in composition content, etc. For example: fish meal varies greatly in protein content and nutritional value depending on fish species and the amounts of phosphorus, viscera, fish bones, salt and moisture it contains, as well as whether it is defatted; the value of oil cakes depends on the oil pressing method, residual oil and moisture content, and the amount of impurities; bran types often have large shell content due to different levels of processing technology, and the degree of spoilage of rice bran containing fat, the amount of flour contained in wheat bran, etc., can cause great differences in quality; meat and bone meal varies in quality depending on the amounts of viscera, bones, hair, blood and other by-products it contains, its degree of spoilage, and processing technology; various additives also differ due to different carriers and ingredient quality. These inevitably cause nutrient imbalance: some nutrients exceed requirements and are wasted, while others are insufficient and affect animal development, and harmful substances can also affect poultry health and product quality. Therefore, ingredients of unstable quality cannot be used to formulate diets, otherwise it will result in poor feeding results, low conversion rates, and high costs; where conditions permit, their nutrient content and quality should be determined as much as possible before use.

  II. Feed Storage Methods

  Feed ingredients or prepared feed must be placed in a dry, ventilated place to prevent mold. During the plum rain season in summer and autumn, they must be turned and sun-dried, and bags must be restacked. During processing, materials purchased earlier should be processed first, and materials purchased later should be processed later, and the old material at the bottom must be cleaned out thoroughly.

  III. Feed Processing Techniques

  For energy and protein feeds, the following methods can be used for processing.

  (1) Grinding and flattening. Generally, grain feeds are rather hard in texture or have husks. Except for a few grains such as corn and sorghum, which can be fed whole when freely eaten, they usually need to be ground or flattened before feeding, with a particle diameter of 0.2-1.0 mm being appropriate.

  (2) Making pellets. After mixing various feeds, put them into a pellet machine to make columnar or spherical shapes for feeding piglets.

  (3) Cooking. Legume seeds such as peas, broad beans, and soybeans, after being cooked, can increase the nutritional value of their protein.

  (4) Roasting. Corn and soybeans are roasted and dried at high temperature (130-150°C), suitable for preparing piglet starter feed.

  (5) Detoxification. Cottonseed (kernel) cake and rapeseed cake can also undergo detoxification treatment before being fed to breeding boars and sows; those not detoxified can be fed to fattening pigs.

  IV. Processing Equipment

  Complete sets of feed processing equipment include the following: mixing machine equipment; ring-die pellet presses; crushing equipment; expansion, drying, and cooling equipment; breaking, grading, and dust removal equipment; conveying, cleaning, and impurity removal equipment.