The Rumen Inside & Out Ruminant Digestive System Rumen Rumen - - PDF document

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Livestock Management CDE Dairy: Nutritional Management

• K. J. Clark, Erin Marotz, and B.A. Reiling

January 26, 2017

University of Nebraska–Lincoln

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Nutritional Management – Objectives

 Students should understand ...

• Ruminant Digestive System Anatomy/Physiology
• Nutritionally based Metabolic Disorders
• Feedstuff ID & Characterization
• Ration and forage sampling & analysis
• Body Condition Scoring
• Scale
• Stage of growth and lactation

University of Nebraska–Lincoln

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Ruminant Digestive System

 Rumen

• Storage (up to 50 gallon capacity)
• Physical mixing
• Fermentation chamber
• Microbes break down cellulose
• Microbes release volatile fatty acids (VFAs) = ENERGY
• Acetate, from “forage digesters”  milk fat synthesis
• Bacterial synthesis of protein & vitamins

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The Rumen – Inside & Out

Rumen Pappillae

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Ruminant Digestive System

 Reticulum – the “honeycomb”

• Forces the “cud” back to the mouth
• Continguous with the rumen (rumeno-reticulum)

Reticulum

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Ruminant Digestive System

 Omasum – “manyplies”; “Stockman’s Bible”

• Absorption of water

Omasum

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Ruminant Digestive System

 Abomasum (true stomach)

• Acidic digestion

Abomasum

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Small Intestine

 Small Intestine (pH ~ 6-7)

• Enzymatic digestion
• Absorption of nutrients
• Glucose, AA’s, Minerals
• Everything except VFAs

Jejunum

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 Large Intestine

• Water resorption
• Storage of undigested food
• Microbial fermentation
• limited absorption

 https://www.youtube.com/watch?v=JSlZjgpF_7g&li st=PLsNJI1PtT462txiSTVe6dgrMEbCDhYjSz

Large Intestine

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Metabolic Disorders to Know

 Milk Fever  Displaced Abomasum  Ketosis  Retained Placenta  Hypocalcemia  Acidocis  Fat Cow Syndrome  Fat Cow Syndrome  Bloat  Liver Absesses  Bloat  Laminitis  Hardware Disease  Udder edema

NebGuide: Dairy Cow Health & Metabolic Disease … University of Nebraska–Lincoln

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Metabolic Disorders What to know?

 What is it?  When is it most likely to occur?  What are the physical signs/symptoms?  How can it be prevented/treated?

University of Nebraska–Lincoln

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Example – Displaced Abomasum (DA)  Definition (What is it?)

• Abomasum distended (gas/fluid)  abnormal position

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University of Nebraska–Lincoln

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Example – Displaced Abomasum  When is it most likely to occur?

• Within 2 wks of calving
• High grains diets before & after calving  DAs

 What are the physical signs/symptoms?

• off-feed, scant bowel movements,
•  milk production, general discomfort

 How can it be treated?

• Surgery

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Feedstuff ID & Characterization

 Corn

 Soybean Meal  Alfalfa hay  Alfalfa silage  Corn silage  Blood meal  Distillers grains  Tallow  Dicalcium phosphate  Beet pulp  Brome hay  Soyhulls  Cottonseed  Limestone  Magnesium oxide  Selenium  Wheat midds  Canola  Salt  Citrus pulp

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Characteristics of Feeds

Feed Energy Protein Fiber Mineral Vitamin Corn X Soybean Meal X Alfalfa Hay X X Limestone X Distillers Grains X X X

Why are each of the following ingredients commonly incorporated into a Dairy Ration?

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Sample Feed and Forage Analysis

 Sample Questions to Answer (from the analysis)

• What is the fat content of this ration?
• What is the dry matter content of this ration?
• How much is the cow expected to consume?
• What is the cost/day to feed this ration?
• What is the expected CP of the milk produced?

What is fat content of this ration? What is DM content of this ration? How much is cow expected to consume?

• - as fed basis
• - DM basis

What is cost/day to feed this ration? What is expected CP of milk produced? What is the % crude protein of the hay? What is the dry matter of the hay?

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 Proper Forage & Ration Sampling  Analysis

• Hay Sampling
• NebGuide: Sampling Feeds for Analysis
• https://www.youtube.com/watch?v=MVfWWaTdB9o
• https://www.youtube.com/watch?v=uQT8w7bHfuA

Possible Skill Activities (Hands-on)

• Ration/Silage Sampling

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Possible Skill Activities (Hands-on)

 Body Condition Scoring

• What is the proper scale for Dairy cattle?
• Know proper BCS for different stages of

production and growth

• Proper assignment of BCS to cows.

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What is the BCS?

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What is the BCS?

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What is the BCS?

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What is the BCS?

 NebGuide: How to Body Condition Score Dairy Cows  https://www.youtube.com/watch?v=wASXNn_CTCU

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Dairy Industry Acronyms

 AA = Amino Acid  ADF = Acid Detergent Fiber  AF = As-fed  BCS = Body Condition Score  CF = Crude Fiber  CP = Crude Protein  DA = Displaced abomasum  DHIA = Dairy Herd Information Association  DIM = Days in milk  DM = Dry Matter  DMI = Dry Matter Intake  EE = Ether Extract (fat)  Mcal = Megacalories, energy  NEL = Net Energy, Lactation  NDF = Neutral Detergent Fiber  Ppm =Parts per million  TDN = Total Digestible Nutrients  TMR = Total Mixed Ration

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Questions & Discussion

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Thank You

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• f Agriculture.