Midterm 2 Flashcards
mastitis
inflammation of the mammary gland
4 classic symptoms of mastitis
- swelling
- heat
- redness (or becomes bruise)
- tenderness (pain)
annual dollar loss due to mastitis
$ 1.5 - 2 billion
cost dollar loss due to
- milk income loss (65%)
- treatment costs
- culling losses
- discarded milk
clinical mastitis
observable (SHRT)
subclinical mastitis
unobservable
mild clinical degree of mastitis
- milk altered: no
- udder affected: maybe
- cow abnormal: no
severe clinical degree of mastitis
- milk altered: yes
- udder affected: yes
- cow abnormal: maybe
parachute (systemic) mastitis
- milk altered: yes
- udder affected: yes
- cow abnormal: yes
- caused by coliform and s. aureus
major mastitis causing pathogens
- coliform organisms
- environmental strep
- staph aureus (MRSA)
- strep ag
environmental organisms
- live in cows environment/ bed/ water/ fecal
- most often occur inbtwn milkings
- strep dysgalactiae
- strep uberis
- coliform organisms (fecal/ ecoli)
contagious organisms
- spread from poor milking techniques, faulty milking equipment, or improper sanitation
- staph aureus
- strep ag
strep ag
- only pathogen that can permanently be eliminated from herd
- can only survive outside of cow for few seconds
how many somatic cells does normal milk have
100,000 - 200,000 cells/ml
more in mastitis milk
macrophage
- white blood cell / leucocyte
- gate keeper/ 1st responder, signals to PMN
- found in uninfected mammary gland
PMN (polymorphonuclear neutrophils)
- white blood cell / leucocyte
- get called in by macrophages after infection to destroy pathogens
- found in infected mammary gland
dead secretory cells
- productive cells dying off
- not defensive
- fewest number of cells
how many somatic cells does mastitic milk have
500,000 - 4,000,000 cells/ml (salty)
mastitic milk vs normal
mastitic:
-more PMN than macrophage somatic cell count
normal:
-more macrophages than PMN
phagocytosis
-process of phagocytes (macrophages and PMN) searching out, ingesting and killing foreign bacteria
why do cows get infections
- insufficient number of leucocytes (previous or current infection, stress with calving)
- leukocytes not functioning properly (blood vs milk differences, hormone influence)
mastitis detection tests
- evaluate blood mammary gland leakage
- somatic cell count (SCC)
high scc / mastitic milk
- decrease because produce ate a lower rate (fat, lactose, total casein)
- increase of blood born components (sodium, chloride)
tests on bulk milk
- SCC (can detect bug, but not specifically which one)
- direct bacteriological screening (grow bacteria to tell pic bug) $$
- conductivity, lactose, NAGase, BSA tests
cow factors of mastitis
- udder / teat conformation
- age
- stage of lactation (dried off week, calving week)
- heredity
environmental factors of mastitis
- feeding times / content (will lay down after milking unless food out)
- housing
- general sanitation
microbial factors of mastitis
- general sanitation
- minimizes but does not eradicate mastitis
5 point plan mastitis prevention
- use good milking machines in correct manner
- dip teats after milking
- administer full series of antibiotics
- treat each quarter
- cull chronically infected animals (kill)
milk components that decrease due to mastitis (decreased synthesis)
- casein (2.8 -> 2.3)
- lactose (4.7 -> 4.0)
- fat (4.2 -> 3.7)
milk components that increase due to mastitis (leakage form blood)
- whey protein (.8 -> 1.3)
- chloride (.091 -> .147)
- sodium (.044 -> .06)
functional type traits
- feet, leg
- udder
- structure with reproduction
guidelines to evaluate dairy cows
- cow sense / knowledge of cow parts
- knowledge of ideal type for each breed
- remember cows
- fairness and honesty
- patience with cows
- fluent in dairy terms
- dedication to practice
frame
- 15 %
- silhouette of top line (withers to tail head)
- wide rump
- breed character
- strength in front end
- hooks to pins slope
rear feet and legs
- 20 %
- strong feet and legs placed right
- not puffy hocks
- short strong flexible pasterns
dairy strength
- 25 %
- cleanliness, sharpness, angles
- strong looking
- flat open ribs at angle
udder
- 40 %
- smooth/ flat/ thick fore attachment
- depth relative to hock (above hock good)
- deeper crease/ cleft = stronger median suspensory ligament
- teat placement
when are herds judged / classified
7 month intervals to see cows in different stages of lactations
animal analysis association (aAa)
- takes bull strength and cow weakness to produce desired offspring (corrective mating)
- bull value resides in his daughters
puberty
period wen animal reaches sexual maturity
estrous cycle
- 21 days
- cycle of egg development, ovulation, migration, regression
etrus
- 12-18 hrs
- specific time during estrous when female is receptive to male
open vs. settled
open: not pregnant
settled: recently diagnosed pregnant (40-60 days)
primary sex organ of male
testes
testes
- 1-4 degrees cooler tan body
- drop when hot, hide when cold
- produce testosterone (male sex hormone that develops secondary sex characteristics)
epididymus
- duct leading out of testes
- absorbes (reducing fluid volume)
- secretes (maintains sperm viability)
vas deferens
- duct connecting epididymis and ampulla
- ductus deferens
ampulla
- passageway for sperm
- powerful muscle tissue
- expulsion of semen from ductus deferens into urethra
urethra
passageway for urine and reproductive systems
accessory sex glands
- seminal vesicles
- prostate
- cowper’s gland (bulbourethral gland)
- secrete fluid to increase sperm viability
- secrete fructose and citric acid (buffers to resist changes in pH)
penis
-sigmoid flexure (s-saped curve) straightens wen excited to allow extension into vagina
sheath
- protective covering of penis in relaxed state
- grasped in AI (not penis!)
sperm secretion of bull
- 5 cc
- 2 billion sperm per cc
- 10 billion sperm overall
sperm secretion least to greatest
- ram (.8 - 1.2)
- human (2 - 6)
- bull (5)
- stallion (40 - 100)
- boar (150 - 200)
spermatogenesis
- bull produces less than stallion and boar
- total sperm productivity increases up until age 7
bull puberty
- occurs at 6-12 months (jerseys earlier than holsteins)
- used for regular collection at 18-20 months
ovary
- primary female reproductive organ
- produces eggs, hormones, secondary sex characteristics
- estrous cycle
- maintains pregnancy (secreting progesterone)
graafian follicle
- blisters on surface of ovary
- fluid filled cavity
- produces estrogen
corpus luteum
- produces progesterone
- thick yellow
- maintains pregnancy
ovulation
- release of egg from ovary
- 1 egg released per estrous cycle
- born with all eggs
fallopian tube / oviducts
- where fertilization occurs
- sperm meet egg
uterine horns
where calf forms
uterine body
where AI straw is administered (just after cervix)
cervix
- physical barrier against outside entities
- affects pregnancy bc many sperm cells die here
- separates vagina and uterus
- “non heat days” covered in thick mucus
- estrus hours mucus is thin, clear, stringy
vulva
only visible part of cow
polyestrous
- year round ovulation, cyclic
- ex. cows, sow, rats
seasonally polyestrous
- ovulation on a regular cycle for a portion of the year
- ex. mare, ewe
diestrous
- twice a year
- ex. dogs
monoestrous
- one fertile period per year
- some birds, whales
signs of estrus
- mucus
- mounting and riding other cows
- standing to be ridden
- off feed / milk production
- bawling
- nervous, excitable (pedometer track steps)
follicular phases of estrous cycle
- proestrous (1 day)
- estrus (12 - 18 hrs)
- ovulation 12 hrs after estrus (breed AI to match)
luteal phases of estrous cycle
- metestrus (7 days)
- diestrus (11 - 11.5 days)
cow puberty
- 6 - 9 months if fed correctly
- 800 - 850 lbs by 13-15 months old
gestation
283 days
parturition
- calving
- holstein calf: 80-120 lbs
- jersey calf: 45-80 lbs
1 ejaculate can impregnate ____ cows AI
300 cows
history of AI
- arabs started with mare
- italians with dogs
- russians with horses
- denmark with cows (1936)
- E.J Perry first us bull stud NJ
methods of AI
- copulation (spoon)
- massage
- electroejaculator
- artificial vagina
electroejaculator
- most common in majority species, exotic animals, untrained
- disadvantage: muscle tremors, injury to bull, spermless ejaculate
artificial vagina
- preparation and procedure try to imitate natural conditions
- temp (106-110 degrees)
- lube
- texture
semen evaluation
- concentration (enumeration)
- motility (ability to move effectively)
- viability (alive= clear, dead = blue / 85% live typical)
- morphology (shape and form)
extender / semen dilute
- egg yoke (nutrients for sperm)
- citric acid (prevents pH changes)
- antibiotics (protect against disease)
- glycerol (protect in negative effects of cooling and freezing in liquid nitrogen)
advantages of AI
- wider use / more daughters
- higer quality semen
- cost
- disease control
- injured bulls can do it
- bull proving (through daughters)
- danger w bulls
disadvantages of AI
- observe heats
- semen care and handling
- record keeping (cheats, semen inventory)
- time
- training
