Quiz 5 Flashcards

Question

Process of Homogenization

Answer 1

Milk fat globules are forced through a narrow gap so they break into smaller globules that are stable in the emulsion Small droplets will still want to aggregate but they are easily separated Two-stage process

Answer 2

Most economically impactful disease in dairy production due to its prevalence and impact

Answer 3

Physical Force (Trauma) Infectious Agents (Bacteria)

Answer 4

Colonization by pathogen - adhesion to mammary epithelium - expression of virulence factors - production of toxins Inflammatory Response of Cow - increased vascular permeability - leukocyte migration - phagocytosis Spontaneous Cure, Clinical Case, Subclinical Case

Answer 5

18.6 Million Dollars in Virginia 2 Billion Dollars in US (OLD NUMBERS) 23% Replacement Cost 6% Discarded 5% Treatment 66% Reduced Milk Production

Answer 6

Milk loss begins at SCS of 3 or SCC 72,000-141,999 at 1.5 pounds less per day For every one increase in SCC there is a 1.5 pound increase in milk loss

Answer 7

- Inflammatio = set on fire - Response to injury ○ Inflammation is part of the healing response ○ Deliver defensive materials (cells and plasma proteins) to a site of injury - Role in repair and remodeling of tissue Heat, Redness, Swelling, Pain, Loss of Function

Answer 8

Clots in milk after stripping

Answer 9

Incidence of mastitis increases when defense mechanisms of the mammary gland are impaired. ○ The Transition Period - Reduces Immune function and increases susceptibility

Answer 10

Management and Environment - 90% Genetics - 10%

Answer 11

Calving Dry-Off ○ If there are pathogens in the mammary system, when we stop milking we are no longer flushing those out and they have the ability to grow in the mammary system Transition Period

Answer 12

Environment Bacteria Cow Environment x Cow = Stress Environment X Bacteria = Spread Bacteria x Cow = Exposure

Answer 13

Once a pathogen enters the mammary gland it can grow faster than it can be controlled and the bacteria adhere to the mammary epithelial and colonize the mammary gland Virulence factors improve the survivability of the pathogen in the mammary gland

Answer 14

Increased vascular permeability to move more immune cells into the interstitial fluid and mammary gland White blood cells engulf pathogens

Answer 15

Proper maintenance/use of milking equipment Teat Dips/Proper Milking Procedure Treat Clinical Cases Dry Cow Therapy Cull

Answer 16

Contagious ○ Spreads from animal to animal ○ Sometimes bacteria varieties are those which use the mammary system as a host Opportunistic ○ Cause infection if they have the opportunity but live other places Environmental ○ Found in the environment but may cause infection

Answer 17

Spread from cow to cow during milking § Preventing cross contamination between infected and healthy cows primary source is infected udders transmission at milking usually establish chronic subclinical mastitis

Answer 18

CONTAGIOUS PATHOGEN Gram positive cocci Beta hemolytic Capsule Obligate pathogen of the udder Problematic in the past but not seen often anymore

Answer 19

CONTAGIOUS PATHOGEN Gram positive cocci Sphere Shaped (cocci) Grow in Clusters (Staphylo) Colonize skin, nasal cavity, mucous membranes Thrives on unhealthy skin Multiple virulence factors § Help the organism be infective § Adhesin - ability to couple with the epithelial surface § Capsules, slime - factors that prevent access of IgG and Complement § Protein A - Bind antibodies in the wrong way § Coagulase - breaks fibrinogen S. aureus is very difficult to control within the dairy industry Can cause abscess and clot formation in the mammary system If the clot blocks the mammary ducts there is regression of the lobe or lobule

Answer 20

Contagious Pathogen

Answer 21

Coagulase Negative staphylococcus Primary Source is on healthy teat skin and milker's hands Transmission is related ti bacterial load on teat ends Common in heifers, often right after calving Detected in ~25% of lactating cows § Rate changes with stage and number of lactation About half of infections are persistent § Dependent on pathogen § Not easy to control Readily eliminated with efficacious post milking teat dipping Dry cow therapy eliminated most existing infections New infections at calving respond to lactation therapy

Answer 22

Primary source is the cow's environment Transmission of bacteria occurs between milkings Incidence is higher in herds that control the contagious pathogens § Eliminating one pathogen creates the opportunity for other pathogens to infect the mammary system due to decreased competition Coliforms § Present in the environment of all dairy cows □ Gram Negative Rods □ Differentiation ® MacConkey Agar ◊ Selective for gram negative and Lactose Fermentation = pink colonies

Answer 23

Staphylococcus chromogenes Staphylococcus hyicus Staphylococcus warneri Staphylococcus epidermidis Staphylococcus simulans Staphylococcus xylosus Staphylococcus sciuri

Answer 24

Escherichia coli Klebsiella species Enterobacter species Streptococcus uberis Streptococcus dysgalactiae

Answer 25

The immune system is responding to the toxins, not necessarily the bacteria In severe coliform infections, the infection can take over the whole body

Answer 26

Part of the cell wall of most gram negative bacteria Consists of three components - O Side Chain - Inner Core - Lipid A

Answer 27

Typically controlled by the cow herself Treatment Considerations ○ “Stripping out” mild clinical cases of coliform mastitis is preferred ○ Most coliform infections are cleared by natural defenses of the host ○ Supportive therapy is important § For when the infection is systemic § IV Fluids § Fever = Systemic Response ○ Vaccine § Does not prevent the infection but reduces the effect of the toxin

Answer 28

Opportunistic (soil pathogen) Bad infusion practices

Answer 29

◦ Opportunistic (soil pathogen) ◦ Bad infusion practices

Answer 30

Colorless algae (water/soil pathogen) ◦ Bad infusion practices

Answer 31

Bad infusion practices Bacillus spp. Bad infusion practices

Answer 32

Environmental Water Drop hoses

Answer 33

Environmental On blood agar, it will swarm across the plate

Answer 34

Contagious Outbreak preceded by respiratory disease

Answer 35

Used for Detection and Diagnosis of Mastitis Measures nuclear DNA Equal volume milk and CMT solution Mix by rotating in circular motion Determine gelling by rocking back and forth Degree of thickness will determine degree of inflammation

Answer 36

Increases in milk to combat bacteria

Answer 37

Identifies specific pathogens Therapy recommendations Culling decisions

Answer 38

Before drying off At calving Clinical symptoms High SCC

Answer 39

Inhibit Growth

Answer 40

Alexander Flemming - Penicillium notatum mold inhibited the S. aureus growth on his culture Howard Florey and Ernest Chain - Mass production of penicillin for human use

Answer 41

Inhibition of Cell Wall Synthesis Inhibition of Protein Synthesis Inhibition of Synthesis of Essential Metabolites Injury to Plasma Membrane Inhibition of Neucleic Acid Replication and Transcription

Answer 42

Nosocomical Infections Animal Treatments and Feed Additives Inappropriate Treatment Regimes Premature use of Last Resort Drug Failure to confirm culture and susceptibility

Answer 43

Many consumers have allergies to antibiotics

Answer 44

Pre and Post Milking Teat Disinfection Blanket Dry Cow Therapy Proper Treatment of Clinical Cases Regular Milking System Analysis and Maintenance Cull Chronically Infected Cows Monitor High SCC

Answer 45

Staphylococcus aureus Streptococcus agalactiae Prototheca C. bovis

Answer 46

Coliforms Streptococcus dysgalactiae Streptocuccus uberis Environmental Strepts