Lecture 1 2 animal feed and nutrition

Microsoft Word Lecture 12 Animal feed and nutrition docx Lecture 1 2 Animal Feed and Nutrition In this lesson you will study some of the key terminologies commonly used in Animal Feed and Nutrition.Chuyên ngành bác sĩ thú y

Lecture 1 & 2: Animal Feed and Nutrition

In this lesson you will study some of the key terminologies commonly used in Animal Feed and Nutrition Your class will be divided into small groups of 6-8 students and each group will discuss some aspects relating to the feed ingredients, nutrient categories, and digestive systems Additionally, you will be asked to do some exercises about those terms to make sure that you understand and use them correctly

vKey terminologies

-Abomasum (n): dạ múi khế

-Antinutrient (n): kháng dưỡng chất

-Antinutritional (adj): kháng dinh dưỡng

-B-complex vitamin: vitamin nhóm B

-Broiler (n): gà thịt

-Brush border (microvilli): vi nhung mao

-Bulk density: tỷ trọng khối, mật độ khối

-By-product (n): phụ phẩm

-Cattle (n): đại gia súc (chủ yếu là bò)

-Cecum (n): manh tràng

-Cereal (n): ngũ cốc

-Cleaning of rice: lau gạo

-Colon (n): kết tràng

-Compartmentalize (v): chia thành ngăn

-Conventional (adj): thông thường, truyền thống

-Coprophagy (n): sự ăn phân

-Dehull (v): tách vỏ

-Diagnose (v): chẩn đoán

-Digestibility (n): khả năng tiêu hóa

-Digestible energy: năng lượng tiêu hóa

-Dispensable (adj): không thiết yếu

-Disrupt (v): phá vỡ

-Duodenum (n): tá tràng

-Element (n): nguyên tố

-Energy-yielding ingredient: thực liệu cung năng lượng

-Epithelium (n): biểu mô

-Essential (n): chất thiết yếu, chất cần thiết

-Excrete (v): bài thải

-Fat-soluble vitamin: vitamin tan trong chất béo

-Feces (n): phân

-Fermentation (n): sự lên men

-Fiber (n): chất xơ

-Filamentous web: màng sợi

-Foreign matter: ngoại vật

-Germinate (v): nẩy mầm

-Gross energy: năng lượng thô

-Growth depression: suy giảm tăng trưởng

-Growth rate: tốc độ tăng trưởng

-Gut (n): ruột

-Heat treatment: xử lý nhiệt

-Hemagglutinin (n): ngưng kết hồng cầu

-Hypertrophy (n): triển dưỡng

-Ileum (n): hồi tràng

-Indispensable (adj): thiết yếu

-Inhabit (v): sống ở (nơi nào)

-Inhibitor (n): chất ức chế

-Jejunum (n): không tràng

-Kernel (n): hạt

-Macroelement (macromineral, n): khoáng đa lượng -Metabolizable energy: năng lượng trao đổi

-Microbe (n): vi sinh vật

-Microvilli (n): vi nhung mao

-Mineral (n): chất khoáng

-Mold infestation: sự nhiễm nấm mốc

-Net energy: năng lượng thuần

-Nutritive value: giá trị dinh dưỡng

-Omasum (n): dạ lá sách

-Pancreas (n): tụy tạng

-Polishing: lau bóng gạo

-Pollard (n): cám mịn

-Pouchlike (adj): dạng túi

-Poultry (n): gia cầm

-Projection (n): gai lồi

-Ration formulation: tổ hợp khẩu phần

-Rectum (n): trực tràng

-Reticulum (n): dạ tổ ong

-Rice bran: cám gạo

-Rumen (n): dạ cỏ

-Ruminant (n): thú nhai lại

-Secrete (v): tiết ra, tạo ra (1 chất, dịch)

-Soybean meal: khô dầu đậu nành

-Strain (n): giống

-Substance (n): chất

-Swine (n): heo

-Toxin (n): độc tố

-Trace element (microelement, n): khoáng vi lượng

-Uncooked (adj): chưa nấu chín, còn sống

-Under-heated (adj): gia nhiệt chưa đủ

-Variety (n): giống (thực vật)

-Water-soluble vitamin: vitamin tan trong nước

vReading

Corn

Corn has become the standard against which other cereals, cereal by-products and other energy-yielding ingredients are compared In most poultry diets, corn will be the major contributor

of metabolizable energy World production is around 600 m tonnes of which 240 m tonnes are produced by the U.S.A Although China is the world’s second largest producer at around 100 m tonnes, Brazil at 40 m tonnes, is the second largest world exporter The feed industry usually uses the equivalent of U.S.A grade #2 As grade number increases, bulk density declines and there are greater permissible levels of damaged kernels and foreign matter allowed in the sample Corn grade

#2 should contain no more than 5% damaged kernels and 3% foreign material While damaged kernels are unlikely to affect its energy value, foreign material is likely to reduce its energy value and hence monetary value Broken kernels are also potential sites for mold infestation Most corn samples contain 3 – 4% oil, although newer varieties are now available which contain up to 6–8% oil, and so contribute proportionally more energy

Rice by-products

Rice by-products are the result of dehulling and cleaning of brown rice, necessary for the production of white rice as a human food Rice products are one of the most common cereal by-products available to the feed industry, with world production estimated at around 45 m tonnes The by-product of preparing white rice, yields a product called rice bran, which itself is composed of about 30% by weight of rice polishings and 70% true bran In some regions, the two products are separated, being termed polishings and bran Alternatively, the mixture is sometimes called rice bran, whereas in other areas the mixture may be called rice pollards The polishings are very high in fat content and low in fiber while the true bran is low in fat and high in fiber The proportions of polishings and true bran in a mixed product will therefore have a major effect on its nutritive value

Soybean meal

Soybeans contain a number of natural toxins for poultry, the most problematic being trypsin inhibitor As with most types of beans, the trypsin inhibitors will disrupt protein digestion, and their presence is characterized by compensatory hypertrophy of the pancreas Apart from reduced growth rate and egg production, presence of inhibitors is therefore diagnosed by a 50-100% increase in size

of the pancreas Fortunately, the heat treatment employed during processing is usually adequate to destroy trypsin inhibitors and other less important toxins such as hemagglutinins (lectins) In developing countries, trypsin inhibitor levels are sometimes controlled by fermentation or

germinating beans, where after 48 hrs of treatment, protein digestibility is almost equivalent to that seen in conventionally heated beans

Discussion about soybean meal quality invariably involves the significance of trypsin inhibitor relative to other antinutrients It is often claimed that only about 50% of the growth depression resulting from consumption of under-heated soybean meal is due to active trypsin inhibitor The other antinutrients of importance are isoflavones, lectins and oligosaccharides Lectins are antinutritional glycoproteins that bind to the intestinal epithelium resulting in impaired brush border function Such ‘thickening’ of the epithelium results in reduced efficiency of absorption There are strains of soybeans that contain no lectins, and so studying their feeding value provides some information on importance or not of lectins Feeding uncooked lectin-free soybean meal produces greater broiler growth than does feeding regular uncooked soybean However, the growth is still less than using trypsin inhibitor-free soybeans These data support the concept that lectins are much less important than are trypsin inhibitors in assessing nutritive value of soybean meal

Nutrient categories

A nutrient is a dietary essential for one or more species of animals Not all animals require the same nutrients For example, ruminants (cattle, sheep, goats, etc.) have quite simple nutrient requirements in comparison to nonruminant (monogastric) species, such as swine, poultry, and humans All of the known nutrients are in one of the following categories: protein, carbohydrates, lipids (fats and oils), minerals, vitamins, and water

Protein: Protein is composed of substances called amino acids The indispensable amino

acids must be provided in the diet (or in the case of ruminants), are synthesized by microbes in the gut) Those that can be synthesized in animal tissues are referred to as dispensable amino acids, because they are nonessential in the diet They generally are not of concern in ration formulation

Minerals: Various mineral elements are dietary essentials for animals Some of them are

required in relatively large quantities These are termed the “macroelements” or macrominerals” Others are needed in very small (trace) amounts and are referred to as the “trace elements” or microelements”

Vitamins: Fat-soluble vitamins are stored in fatty tissues of the body and are poorly

excreted Thus, a long period of time on a deficient diet is needed for a deficiency of fat-soluble vitamins to occur In contrast, water-soluble vitamins (except vitamin B12) are readily excreted in the urine If they are not provided in the diet, they rapidly become deficient because they are poorly stored in the body Vitamin B12 is efficiently stored by the liver, unlike the other water-soluble vitamins With the exception of vitamin C, the water-soluble vitamins are also referred to as the B-complex vitamins

Digestive tract

Monogastric animals have a pouchlike, noncompartmentalized stomach and do not depend much upon microbial digestion in any part of the gut They accomplish their own work of digestion,

by digestive enzymes secreted into the gastrointestinal tract The major site of digestion and absorption in a monogastric animal is the small intestine, consisting of three segments, the duodenum, jejunum, and ileum Digestion is completed by enzymes in the brush border or intestinal mucosa The mucosa is made up of projections, called villi, which in turn have minute projections called microvilli At the tips of the microvilli are filamentous webs, the glycocalyx The stomach and small intestine are referred to as the foregut The hingut is composed of the the cecum, colon, and rectum Bacterial growth in the hingut results in synthesis of B-complex vitamins This can be

of nutritional significance in animals that consume their feces, a practice known as coprophagy

A ruminant animal differs from a monogastric animal in two major respects It has a large, compartmentalized stomach which consists of rumen, reticulum, omasum, and abomasum, and muck of the work of digestion is accomplished by microbes that inhabit the large stomach, rather than by enzymes the animal produces itself