Practical Beef Nutrition- Ruminant digestive anatomy o Basically comes down to degradable vs. undegradable protein in cattleo You have to remember that microbes change the nature of proteins- Protein in ruminantso Non-ruminant:  High quality protein in diet  high quality protein in tissues Medium quality protein in diet  medium quality protein in tissues Low quality protein in diet  low quality protein in tissueso Ruminant: High quality protein in diet medium quality protein in tissues Medium quality protein in diet  medium quality protein in tissues Low quality protein in diet  medium quality protein in tissueso Remember that ruminants have microbes that can change the nature of proteins This makes it not worth feeding them super high quality and exact amino acids need because the microbes can alter things so drastically- Rumen degradable proteino RDP (nonprotein nitrogen)- the portion of dietary protein that can be degraded in the rumen, the largest of the multi-compartmental stomach, by microorganisms (both bacteria and protozoa) that use the protein to manufacture high quality microbial cell proteins, also known as microbial crude protein (MCP) o RUP content is not constant across feedstuffso Sources High: NPN, CG (corn gluten) Feed, soybean mill, cottonseed (good source of RDP) Low: CSM, wet brewer’s grains, CG meal - Rumen Undegradable Protein:o RUP: the portion of dietary protein that escapes degradation by ruminal microorganisms and is passed into the small intestine for digestion andabsorption. The proportion of total feed protein that is undegradable is not constant from one feedstuff to another. Although frequently referred to as bypass proteins, they technically do not bypass the rumen, but are simply notutilized by the microorganisms as a substrate to make MCP. They do not “bypass” the rumen they are just not used in the rumen and go on through absorption and then absorbed later in its true form as its amino acid. - Protein dynamics of a ruminanto They can recycle the proteins in the saliva- How much protein do beef animals need?o If CP= RDP = RUPo RDP MCPo MCP +RUP =MP CP- Crude protein MCP-metabolize crude protein- Requirementso Energy o Protein o Mineralso Vitamins and water- Life stage considerationso Calf requirements Energy, proteino Gestation requirements- will need an increase in basically everything because now she is feeding for two now instead of one Protein (will gradually increase), energy, vitamins, minerals, o Lactation requirements Calcium, energy (really need this)o Development requirements (heifer and bull)- you want to restrict them a little bit, project out what you want them to grow and then make a diet for them. (you don’t want to over grow or over develop). Protein (growing requirements)o Growing requirements (beef) Energy (how much can you get in them in safely and quickly) - When calculating this remember to:o Program how much they will gaino How fast do you want them to gaino Everyone will require maintenance you have to exceed this for any growth you want them to achieve. o In a lactating mother you have to remember that the first few months she is producing milk (will peak around month 2&3) Then around months 3&4 she is rebred Earlier weinging is to save both the mother and the baby (when you can not meet all of the requirements) o You have to consider ADG (average daily gain) This is the minimum that they need to be fed  you can push this limit to make them gain - Requirement Calculationso Requirements are formulated by a committee using reported data from research studieso The committee has developed equations that used to calculate requirements based on various factors  Life stage Production goal  Environment o Can be complicated: NEm Numerous factors (age, physiological state, wind speed, temperature, heat production, terrain, breed, hide cleanliness, etc.)o Can be less complicated: MPmaint = 3.8 Ü SBW0.75 SBW- shrunk body weight  tries to calculate the actual weight of the body (we typically think of this as 96% of the live weight) - 4% (6-6%) is the rumen and other yucky stuff- Ruminant feedstuffso The ruminant digestive tract allows for nearly unlimited feedstuffso Feedstuffs are typically segregated into groups of similar nutritional content:o Forages Fresh or preserved Microbes help to break down the cell wall structure Used for both protein and energy Primary feedstuff for- Mature animals (bulls, cows)- Breeding animals (replacement heifers, cows, bulls) Highly variable- digestability can change due to lots of different factors (growing season, rain etc.) Examples:- Pasture, hay, silages, haylageso Proteins Feedstuffs that are used to balance protein deficiencies within a diet Examples:- Oilseed meals (cotton, soy, canola)- Some forages (alfalfa, clover)- By-products (WDGS, DDGS, Corn Gluten Meal, solubles)- Animal Meals (Feather, fish meat meals)- Protein tubs Soluble- the liquid from fermentation o Energy- Carbohydrates AKA: “High-concentrate” Feedstuffs Readily fermentable carbohydrates Can cause upset stomach  Examples: - Cereal grains- Tubers - Molasses Process so that it is easier to digest and so that they will eato Energy-By-products Used for both energy and protein  Wet and dry distillers grains (comes from ethanol production) Wet and dry corn gluten meal (comes from high glucose corn syrup extraction) Corn gluten feed Brewer’s grains (alcohol production) Grocery waste  Beet pulp Bakery waste Citrus pulp Ponch- the stomach/rumen contents from a kill planto Energy-Fats The most energy dense nutrient Key for high-energy diets Important limits that can hinder performance if exceeded Mainly for feed lot cattle  It can hinder performance so you have to be careful with amountso Supplements- Vitamins, Minerals, Feed Additives Usually fed as a meal, block, or pellet Includes all macro and micro mineral and vitamins  Can include feed supplements- MGA- used to reduce estrus in heifers (feedlots)- so aka birth control- Monensin- alters the rumen environment- Tylosin- antibiotic that isknown for preventing liver abscesses - Bloat preventative - Growth promotants - Nutritional disorders in beef cattleo Common disorders can be classified into major categories: Toxicities  Deficiencies Digestive upset-