Exam Flashcards
How are sperm released in isthmus?
Capacitation
what is capacitation
biochemical changes that cause destabilisation of the sprem membrane
when does capacitation occur
ass soon as they are in the female reproductive tract
what is hyperactive motility
shift in flagellar movement from progressive linear to accelerated excited
how is sperm guided to oocyte
thermotaxis and chemotaxis
what is acrosome reaction
release of enzymes after membrane fusion which allows sperm to penetrate zona pellucida
where does fertilisation occur
perivitelline space
steps in oocyte activation (4)
increase in intracellular ca
cortical reaction
resumption of meiosis
decondensation of sperm nucleus
what is cortical reaction and why is it good
exocyotosis of cortical granules in to perivitelline space. it causes a change in zona pellucida so sperm cannot enter
purpose of cortical reaction
prevention of polyspermy
what is superfecundation
fertilisation of 2 or more ova from same cycle, separate from acts of intercourse (in bitches and queens)
fertile life of sperm in cow
28-50h
fertile life of sperm in mare
144h
fertile life of sperm in bitch
144h
fertile life of sperm in sow
36h
what is spermatogenesis
process by which spermatozoa are formed
where does spermatogenesis occur
seminiferous tubules
puberty age bull
10-12 months
puberty age stallion
13-18 months
puberty age dog
5-10 months
puberty age boar
4-8 months
puberty age ram
4-6 months
purpose of leydig cells
interstitial
have LH receptors
produce testosterone
purpose of sertoli cells
supportive cells
remove excess cytoplasm from spermatids
produce estradiol, inhibin and antimullerian hormone
spermiogenesis
morphologic differentiation of spermatids
phases of spermiogenesis (4)
Golgi phase - golgi vesicles form to produce large acrosomal vesicle
cap phase - golgi migrates to caudal part of cell, formation of cap and flagella
acrosomal phase - nucleus elongates and neck and annulus is formed
maturation - mitochondria form spiral around flagella and plasma membrane formed
spermiation
release of spermatozoa from Sertoli cells in to lumen of seminiferous tubules
where does maturation of sperm occur
epididymis
semen contains
sperm and accessory gland secrete
fertilisation
union of nuclei of male and female gametes
what do cumulus cells do during fertilisation (2)
attract, trap and select sperm
facilitate capacitation and acrosome reaction
natural semen deposition stallion
intracervical or intrauterine
natural semen deposition bull
intravaginal
natural semen deposition dog and tom
intravaginal
natural semen deposition boar
intracervical
who has high volume, dilute semen
boar and stallion
who has low volume, highly concentrated semen
bull, dog, ram
what is retrograde flow
sperm getting washed out in mucous
how to prevent retrograde flow
ejaculate fractions - boar, stallion, dog
uterine deposition - stallion
2 types of sperm transport
rapid - sperm reach oviduct within a few mins
sustained - sperm reach oviduct in 4-6h and will be involved in fertilisation
types of cervical mucous
sialomucin - high viscosity in central part of cervical channel
sulfomucin - low viscosity in cervical folds
4 events of follicular phase
increase GnRH from pituitary
follicular growth and prep for ovulation
sexual receptivity
ovulation
stages in follicle wave and hormones (4)
recruitment - increase FSH, decrease LH, inhibin and estradiol
selection - decrease FSH, moderate LH, decrease inhibin
dominance - increase LH and inhibin, decrease FSH
atresia - degeneration
what initiates ovulation
LH surge
who are induced ovulators
queen, ferret, rabbit
how does induced ovulation work
copulation causes GnRH release, then LH and LH acts on follicle
luteal phase
formation of CL and secretion of progesterone
CL development (4)
basement membrane cells deteriorate due to collagenase
complete separation causes granulose and theca internal cells to mingle, there is local bleeding and follicle collapses
basement membrane forms connective tissue of CL and C hemorrgahicum lasts 2-3d
CL made from large luteal (granulosa) and small luteal (theca international) cells and connective tissue and produces progesterone
oogenesis
formation, development and maturation of an ovum
3 steps of oocyte maturation
meiosis
cytoplasmic maturation
expansion of cumulus oophorus
what triggers meiosis
preovulatory LH surge
when does meiosis 1 occur
during fetal life
what is purpose of mitotic arrest
to protect genetic material
what causes super ovulation
too much eCG, FSH or for embryo transfer
in what stage is oocyte ovulated
metaphase of meiosis 1 - finishes meiosis after fertilisation
5 sexual reflexes
approach
erection
mounting
copulation
ejaculation
what is a sexual reflex
response to external stimulus, received by sensory organs. congenital or acquired
what happens during approach
sperm moves from epididymis to ampulla of vas deferens so there is optimum amount in ejaculate
what happens during erection
muscle relaxation and vasodilation so blood can’t drain from corpus cavernosum leading to prolapse
what do you need for ejaculation
correct temperature, pressure, and moisture
best AI method in mare
frozen 12h before (up to 6h after) ovulation
signs of pending ovulation in the mare
orange slice uterus on US
fish bone cervix
43mm piriform shape, soft fluctuating follicle
white dots in follicular fluid
where to deposit semen doing AI in the mare
intrauterine through vagina
fractions of dog semen
urethral - 0.5-2ml, no sperm, cloudy
sperm - 0.5-6ml, milky
prostatic - 30ml, clear
AI bitch with fresh
when progesterone is 4-10ng/ml, 2-3d post ovulation or 1d and 3d after ovulation if 2x, intravaginally. raise pelvis for 15mins
AI bitch with chilled
day 2 and day 3 post ovulation intravaginal or intrauterine
AI bitch with frozen
day 2 or day 3 post ovulation transcervically or laparoscopic
when to AI bitch best on vaginal cytology
when 80% are cornfield cells
when to AI cow
12h after end of esters or 28-30h after start of standing heat
what is AM/PM rule
if estrous in morning, AI in evening and vice versa
where to put semen when AI cow
uterine body
method for AI of cow
rectovaginal method
how long do sperm have to be in cow to be able to fertilise
6h
when is ovulation in sows
37-41h after start of estrous
3 extenders for boar semen
Guelph, Beltsville, Zorlesco
boar semen and cold
sperm are highly sensitive to cold shock sp have to use ambient temperature extenders
AI semen deposition ewes
intravaginal or cervical
intrauterine if laparoscopic
when is ovulation in ewes
25-30h after start of estrous
when to AI ewe if using natural heat
12-18h after start of oestrus
cervical or vaginal
when to AI ewe if using sponges
45-58h after sponge removal if cervical or vaginal
48-65h after removal if intrauterine
semen deposition when AI goats
intracervical is most common
intravaginal - fresh only
intrauterine - laparoscopic
when to AI if not synchronised goats
12-24h after first positive heat detection
when to AI using sponges goats
1x AI - 43-46h after removal
2x AI - 30 and 50h after removal
nanny goat - 45h after removal
how to AI goats
very quickly (20s)
pipette through cervix 1-2cm
need speculum and light source
non-return rate
number of cows not rebred within a certain specified time post AI
ideal calving interval
365days
ideal calving index
365-375 days
calving index
average calving interval of all cows in the herd
ideal calving to first service interval
60-65 days
voluntary waiting period
time after calving when cows are deliberately left unserved
voluntary waiting period length
45-55days
heat detection rate
cows correctly identified in heat out of those eligible for heat in a certain time period
target heat detection rate
70%
3 week submission rate
percentage of cows receiving at least 1 insemination in first 3 weeks of mating period (after VWP)
target submission rate
70%
calving to conception interval target
85-95 day
days open
average number of days from calving to conception for cows conceiving and days from calving to culling for those that don’t conceive
days open target
120days
first pregnancy rate target
55%
insemination index
number of semen doses divided by pregnant cows
good insemination index
1.4-2
pathogens in cow uterus (3)
E.coli
T.pyogenes
Fusobacterium
acute metritis in cow
within 10d post partum
general health disturbance
red-brown fluid in uterus, white purulent discharge
bad smell
chronic endometritis in cow
21d pp purulent discharge
26d pp mucopurulent discharge
general condition unchanged
post partum metritis in mares
life threatening
causes = dystocia, RFM, older animals (poor uterine tone and fluid pooling)
pathogen = E.coli
signs = increased HR and temp, bad smelling discharge and lethargy
complications = laminitis, MODS, death
treatment = ate, lavage, oxytocin, NSAIDs etc
postpartum metritis in bitch
cause = dystocia, RFM or foetus
pathogen = E.coli, Staph, Strep
signs = anorexia, vomiting, bad smelling discharge, increased temp, no milk
therapy = electrolytes, atb, PGF, oxytocin, ovariohysterectomy
puerperium length in mare
early 5-6d
late 12d
when is involution complete in mares
9-10d pp
what is foal heat
5-12d postpartum. conception can be less due to incomplete involution
lochia in mares
is light and stops 24-48h post partum
puerperium length in sheep
early 7d
late 30d
puerperium length in goat
early 14d
late 25-45d
when is involution complete in sheep
20-25d
when is involution complete in goat
28d
lochia in sheep and goat
red-brown colour then goes pus like
sheep = 5-6d
goat = 12-14d
when in involution complete queen
5-6d fully by 30d
length on puerperium in sow
early 7d
late 18d
involution in sow
rapid for first 5d, then finished by 28d
lochia in sows
lasts no longer than 5d, red then whitish
weaning and ovarian rebound in sows
rapid regression of CL 3d pp
follicles are small during suckling and grow rapidly after weaning
preovulatory LH surge within 7d of weaning
without suckling, oestrus can be 8d pp
length of puerperium in bitch affected by
constitution of bitch
number of pups
delivery duration
involution in bitch
can take 12weeks
lochia in the bitch
black green due to hemochlorin (uteroverdin)
within 12-48h pp changes to mucoid and blood stained
often not seen as bitch licks
bitches and temp pp
3-6d pp there can be temp up to 39.3
steps in puerperium (5)
involution of genital tract
restoration of endometrium
elimination of bacterial contamination
return of cyclic activity
onset of lactation
factors influencing puerperium
age, climate, movement, dystocia, RFM, delayed return to cyclic activity
involution of uterus begins due to
muscle fibre and fatty degeneration with formation of glycogen which enters circulation
what does uterine involution involve
remodelling of caruncles
regeneration of endometrial tissue
decreased blood flow and smooth muscle mass
involution of cervix
constricts within 10-12h
starts cranially and moves caudally
atrophy and shrinkage due to elimination of fluid and decrease in collagen and smooth muscle
restoration of endometrium first 7-10d
loss of fluid and debris (secundus)
lochia
fetal fluids and membranes, mucus of uterine glands, sloshed caruncles and blood from umbilicus
length, composition nd amount depends on species
what happens to caruncles pp
remain in form for 2-3d then blood vessels become constricted leading to necrosis
by 5d pp storm compactum sloughs off as lochia
by 15d pp sloughing is complete
everything is smooth by d19 due to vessel disappearance
elimination of bacterial contamination
uterus sterile by 6-8w pp in normal healthy cow
phagocytosis by migrating leukocytes and uterine contractions remove bacteria
why is early return to cyclic activity good in terms of puerperium
estrogen dominated uterus is more resistant to bacteria
however if contamination is enough to survive first heat then luteal phase may allow bacterial proliferation
factors affecting post partum ovarian cyclicality
BCS, NEB, parity, disease
phases of return to cyclicality
puerperal - from calving until pituitary becomes responsive to GnRH 12-14d
immediate - pituitary responsive to GnRH until first ovulation 14-25d
post ovulatory phase - first ovulation until involution is finished 25-45d
what can increase involution speed
PGF2a 3d pp
when should first ovulation be pp in cow
21d
how to check cyclic return pp in cow
measure progesterone
why does co in NEB not cycle
there is a smaller concentration of LH and IFN-1 which can lead to inactive ovaries, cysts and non functioning CL
classification of abortion
by stage - imminens, incipiens, intractu
by ejected content - completus (viral), incompletus (bacterial)
etiology - infectious, non-infectious
non infectious internal causes of abortion
hormone or endocrine imbalance
umbilical torsion
colic/bloat
twins
weak cervix
non infectious external causes
mechanical - trauma
thermal - cold or heat stress
artificially induced on purpose or accidental with steroids, PGF2a and estrogen
toxic plants and substances
nutritional deficits
early abortions
often complete and no changes suggesting abortion
late abortion
proceeded by changes - swelling of mammary gland, colostrum secretion, softening of pelvic ligaments
prognosis of abortion
favourable for mother providing no complications
early embryonic mortality
up to 15d
autolysis and resorption
causes - gene incompatibility, stress, age, diet, rough rectal, late AI/ovulation
infections - Tritrichomonas foetus, BVD, BHV1, Campylobacter
late embryonic mortality
15-45d
resorption and autolysis, maybe some discharge
causes - luteal deficiency, infections
embryonic phase
from fertilisation to onset of placentation or end of embryo differentiation
still birth
birth of dead foetus from 260d (cow) to term at time when it should be alive
abortion
from 45d-265d in cow
fetal death after organogenesis and before it can survive in environment
embryo differentiation in mare
40d
embryonic differentiation in ruminants
45d
embryonic differentiation in sow
30d
embryonic differentiation in bitch and queen
20-22d
preterm delivery
foetus reached size but organs are not mature enough and can’t live without help
preterm delivery in mare
less than 320d
preterm delivery in bitch
8 weeks
preterm delivery in cow
after 32 weeks
what is normal abortion rate in herd
3-5% per herd per year
outcomes of twins in mares
1 - smaller dies and abortion in 8-9th month of pregnancy
2 - equal sized foetuses delivered to term but weak and die
3 - small dies early and mummifies, large is normal and delivered to term
causes of abortion in mares
twins, fetal abnormalities, umbilical torsion, hydrops of metal membranes
causes of abortion in sows
stress, nutrition, climate
causes of abortion in sheep and goats
stress, nutrition
causes of abortion in bitches
fetal abnormalities, cystic endometrial hyperplasia, pregnancy in body of uterus, low progesterone, toxic/teratogenic substances
infectious abortion causes in queen
FeLV, FHV1, FIP, toxoplasmosis
signs of bacterial or fungal abortion
exudate between chorion and endometrium
congested and oedematous villi
necrotic changes
fetus is autolytic
signs of viral abortion
minimal visible changes on placenta
fetus not autolytic
signs of parasitic abortion
necrosis of cotyledons, fluid and fibrin in cavities, enlarged ln and spleen, lesions on placenta and fetus depend on duration of process
why take FSC as a sample
most agents infect the placenta, enter amniotic fluid and is swallowed by fetus
infectious abortion causes in sow
PRRSV
SMEDI
Aujeskys
infectious abortion causes in cow
Brucellosis
Camplyobacteriosis
Neosporosis
infectious abortion causes in mare
leptospirosis
salmonella
streptococcus
EHV
infectious abortion causes in sheep
brucella
campylobacter
q-fever
infectious abortion causes in goat
brucella
chlamydia abortus
listeria
parturition
delivery of fetus through birth canal on completion of gestation period
stages of parturition
initiation of myometrial contactions
expulsion of fetus
expulsion of fetal membranes
prepartum fetal changes
maturation of lungs
increased thyroid hromones and catecholamines
closure of ductus arteriosus and foramen ovals
increased glycogen reserves in liver
signs of approaching parturition
cow - udder enlargement, vaginal discharge, relaxed ligaments
bitch - drop in rectal temp by 1-2 degrees 24h before, vomiting
mare - waxing up
trigger for beginning of parturition
increase in cortisol from foetus causes increased synthesis of enzymes that convert progesterone to estrogen
physical cause of parturition
increased fetal size causes increased uterine irritability
biochemical cause of parturition
increased fetal activity causes increased CO2 in maternal blood so increased uterine contractility
maternal cause of parturition
relaxin and proinflammatory cytokines cause dilation of birth canal
oxytocin causes uterine contactions
increased placental oestrogen causes PGF release
first stage of labour signs
myometrial contactions
cervical dilation
appearance and rupture of chorioallantois
ends when part of fetus is in birth canal
second stage of labour signs
uterine and abdominal contractions
maternal recumbency and straining
third stage of labour
uterine contractions - helped by suckling which releases oxytocin
loosening of chorionic villi
what is Ferguson reflex
occurs during second stage of parturition, when foetus hits roof of vaginal wall, it triggers abdominal contractions
length of parturition in cow
1 - 4-24h
2 - 0.5-3h
3 - 12-16h
length of parturition in mare
1 - 1-12h
2- 15-30mins
3 - within 3h
length of parturition in sow
1 - 12-24h
2 - 0.5-4h
3 - after 2/3 piglets or within 4h pp
length of parturition sheep and goat
1 - 6-12h
2 - 0.5-1h
3 - within 3-6h
length of parturition in bitches
1 - 4-24h
2 - 1st pup within 2h of start of second stage, 5-60min between pups, up to 24h total
3 - after each pup or within 2h of last pup
3 ways of inducing parturition
induced fetal maturation - ACTH?
induced birth canal relaxation
induced contractions - oxytocin
consequences of prolonged parturition in the mare
uterine cavity decreases in size, pressure applied to umbilicus leading to decreased blood flow, tachycardia, hypoxia and fetal death
gestation length of mare
336 days (11months)
term in mare
300 days
what is maladjusted foal
neurosteroids not working properly and foal hasn’t transitioned properly from sleepy to awake
how to fix maladjusted foal
Madigan method squeeze 20 mins?
red bag presentation
placenta (chorioallantois) has partially or fully separated from endometrium before foal is delivered so foal is not getting any oxygen - have to rupture bag immediately
milking procedure
forestripping - to detect abnormal milk and stimulate complete let down of milk
predipping - do decrease amount of bacteria on teat
wiping - and dry
unit attachment - prevent air entering
post-dipping - post-milking teat is relaxed for 20-30mins, post dip to prevent germs entering (offer food etc to prevent cow from lying down)
why to avoid over milking
can lead to hyperkeratosis which increases the risk of infection so remove cluster when milk flow is decreasing
stages of dry period
active involution 0-30d
steady state involution
lactogenesis and colostrogenesis 15-20d pre partum
nutrition during dry period
2 weeks before dry period - less concentrates, higher fibre
during dry - less concentrates, higher fibres
2 weeks before calving - lower fibre, higher concentrates
groups during dry period
far off dry group
close dry off group (2-3weeks before calving)
milk leakage
due to impaired teat sphincter, often in higher yielding cows at dry off due to incomplete keratin plug formation
increases chance of mastitis
factors of pregnancy
early pregnancy factor (EPF)
progesterone
estrogen
interferon tau
cG
placental lactogen
specific for pregnancy
pregnancy associated glycoproteins (PAG)
what does EPF do
binds to T lymphocytes to prevent embryo destruction and creates a reaction rosette
how does cow and ewe prevent luteolysis during pregancy
interferon tau from conceptus
how does sow prevent luteolysis
estradiol reroutes PGF2a in to uterine lumen where it is destroyed
there are interferons from embryo that
- limit synthesis, release and transfer of PGF2a,
- stimulate PGE formation instead of PGF2a
- change PGF2a from endocrine (blood) to exocrine (uterine cavity)
what is interferon tau good for
biomarker for embryonic mortality and vitality
in mares, when do PAG appear
24d to 35d post abortion or 70d post partum
role of PAG
detection and determination of feto-placental function and survival of foetus
when does placental lactogen appear in cow
from 160d to parturition - higher in fetal blood than dam
what does placental lactogen do
influence on fetal growth and body weight in neonatal calf
synergistic effect to prolactin and IGF1 and 2
can you detect PL in mares
no
endometrial cups
secrete eCG - for development of CL
active 70-130d
possible false positive finding 3 months post abortion
progesterone during pregnancy in the mare
CL 40-70d
fetoplacental unit 150d to parturition
estrogen in pregnant mare
in urine from fetal gonads
important for diagnostic 150-300d
take first urine in the morning
PAG in ruminants
synthesised in cotyledons in mono/binucleate cells of trophoblast
released in to maternal blood after migration and fusion with maternal epithelial cells of endometrium
When is it RFM in cow
12h+ pp
causes of RFM in cow
mechanical obstruction, dystocia, twins, uterine atony, placentitis, abortion
RFM ‘treatment’ in cow
remove manually
as gently as possible, remove uterus content with catheter, oxytocin if atonic, PGF2a to help detachment 5d pp
drugs in cows with RFM
give broad spec atb parenterally if signs of metritis
foam oxytetracycline intrauterine when removed and control involution to prevent accumulation
don’t give intrauterine atb as will decrease the rate of phagocytosis and so prolong retention
when is RFM in mare
2-3h+ pp
drugs in RFM mares
oxytocin not later than 6h after retention
flunxine meglumine
Ca borogluconate due to low serum ionised Ca in mare with RFM
removal of RFM mare
If not out after oxytocin then manual removal - tie outer part in knot, wrap tail, disinfect, press fingers between chorion and endometrium while lightly pulling and twisting outer part
if difficult give oxytocin, NSAID, atb and retry in 4-6h or uterotonics and 10L warm saline in allantochorial membrane
after RFM removal mare
rinse uterus with 10-15L warm saline or water with mild disinfectant (to remove microretentions which could cause metriti, septicaemia and laminitis) 1-2x/d for several days and oxytocin
after rinsing - 2 oxytetracycline foam tablets
antihistamine every 6h and board spec atb
when is RFM in small rums
12h+ pp
RFM in small rums
try to remove manually 2-4h after birth while canal is still open
oxytocin several times a day and atb
RFM in sows
rare
possible for membrane and foetus to be retained and decompose in situ
RFM in bitch
remove manually if possible - if not, oxytocin and atb and monitor for necrosis of placental sites
if nothing helps - ovariohysterectomy
RFM in queens
very rare
treatment is oxytocin and atb
version and flexion of gravid uterus
more of a parturition problem in large animals
therapy is cesearean hysterotomy
torsion of gravid uterus definition
rotation of pregnant uterus on its longitudinal axis which leads to narrowing of birth canal
cause of torsion of uterus
instability of uterus during single horn pregnancy (doesnt happen in twins)
predisposing factors for uterus torsion
excessive movements of dam or foetus
decreased amount of fetal fluid, fall/kick, small non-gravid horn, cow tied up for long periods of time
signs of uterine torsion
uneasy restlessness, parturition not progressing
diagnosis of uterine torsion
vagina - conically closed, can feel rotation of mucosa, shrinkage of front part if greater than 180
rectal - palpate twisted horn and broad ligaments. can only diagnose precervical torsion rectally
important to know side of torsion
treatment of uterine torsion
retorsion - rotate fetus per vagina or roll dam
c-section - if other methods don’t work, long duration or fetus dead
prognosis of uterine torsion
depends on degree of torsion, duration of process and condition of dam
parturient paresis
also called milk fever/hypocalcemia
peracute-acute afebrile, severe metabolic disease
in 72h pp in high producing dairy cows
signs of milk fever
decreased appetite, tremors, hypersensitivity, recumbency, decreased temp, increased HR, bloat, S shape curve of neck, coma, death
treatment of milk fever
Ca gluconate IV
Ca propionate in propylene glycol gel
powdered Ca propionate PO to avoid cardio toxic effecst
vitamin D, P and Mg
repeat for 3-4d to prevent relapse
complications = decubitus, pneumonia
species and prognosis of uterine prolapse
cow = most favourable
mare = dubious, complications -sepsis and laminitis
sows = unfavourable, esp if poor signs
small rums = very sensitive esp if deficient
carnivores = favourable if not too long lasting
prognosis is worse if bladder or rectal prolapse too
treatment of uterine prolapse mare and ruminants
epidural, wrap tail, raise hind end
support uterus above the vulva, rinse with cold water to shrink, check for laceration, lubricate, replace little by little, start near vagina being careful not to invert labia
using fist, put pressure inside whole arm length, make sure uterus is passed cervix and horns are fully everted
empty bladder before replacing
check for bleeding
rinse replaced uterus with warm saline and give small doses of oxytocin
maybe sutures on labia
treatment of uterine prolapse in bitch and queen
laparotomy and pull uterus back through abdomen
if damaged then ovariohysterectomy
atb and NSAIDs
uterine invagination
gravid horn inverts in to its own lumen and then prolapses during 3rd stage of labour
phases of uterine prolapse
1 - uterine wall inverts in to lumen and increased abdominal straining further inverts the wall
2 - inverted wall passes through cervix and vulva etc and gravity pulls more out
causes of uterine prolapse
dystocia, uterine atony, too big fetus, older or cachetic animal, no movement, injuries to repro tract or broad ligaments, forced extraction of RFM in mares
necrosis of placental sites in bitch
cause = uterine infection, dead emphysematous fetus and retained placenta
signs = rapid onset septicaemia and yellow brown lochia
therapy = ovariohysterectomy, abdominal lavage and atb
subinvolution of placental sites
in bitches
most common cause of hemmorhagic vaginal discharge pp
discharge can last 7-12weeks (suspect If more than 3)
common in bitches under 3y and after first whelp
pathogenesis = trophoblast cells down regress or degenerate normally, continue to invade endometrium or myometrium and prevent normal involution
diagnosis = history, signs, biopsy, histopath
treatment is progestogens
MMA in sows
12h-3d pp
bacterial invasion of udder and or urogenital tract and production of endotoxins (if E.coli) which can change hormone levels involved in lactation (insulin, cortisol, prolactin,oxytocin etc)
signs of MMA in sows
anorexia, depression, fever, loss of piglets, vulvar discharge, constipation
treatment of MMA in sows
frequent small doses of oxytocin, atb, flunixin, corticosteroids.
feed piglets
prevention of MMA in sows
10-14d before farrowing move to clean pens, decrease feed to 1/5th a few days before farrowing
first day pp complete feed restriction but water ad lib
why tetany occurs in hypocalcemia
loss of membrane stabilising Ca ions, nerves become more permeable to Na and need smaller magnitude stimulus to depolarise so there is repetitive spontaneous firing of motor nerve fibres
diagnosis of eclampsia in bitches
history, sigs, decreased blood Ca, decreased Mg or K, prolonged QT interval, ventricular premature contractions
mammary gland
modified tubuloalveolar apocrine sweat gland
mammogenesis
from embryonic ectoderm
first there si just parallellinera thickening on the ventral abdominal wall
the ridge is broken in to mammary buds from which functional part of the gland is formed
fetal development of gland under genetic and endocrine control
hormones involved in mammary gland
estrogen - proliferation of duct system
progesterone - development of alveoli
prolactin - development of alveoli and initiation and continuity of lactation
GH - influences growth of duct system and level of milk secretion
adrenal hormone s- small amounts needed for production, too much is harmful
thyroid - regualte speed of metabolic processes
insulin - moves glucose across membranes for milk synthesis
PTH - regulates Ca and P level
oxytocin - causes contraction of myoepithelial cells for milk letdown
false labour in latin
dolores praesagientes
causes fo preterm labour
extreme physical exertion
trauma
drinking cold water
rough vaginal or rectal exma
signs of false labour
restlessness, hunched over, increase HR and RR, smal and empty udder, peliv ligaments tense, closed cervix
therapy of false labour
leave animal alone
wam thigh ans sacrum area with blanket
maybe Xylazine or procaine epidural
mastitis definition
inflammation of parenchyma of mammary gland, regardless of cause
clinical v subclinical mastitsi
clinical - physical and chemical changes in milk and gland
subclinical - not really detectable / no obvious signs
pathogens of mastitis can be
contagious - S.aureus, M.bovis
opportunistic - Coagulase neg Staph
Environmental - coliform - E.coli, Klebsiella
sources of mastitis infection
contagious - through milking process
environment - pathogens in beddign etc
risk factors for mastitis
older, increase temp, low SCC, udder hygiene, milkin hygiene, early dry period and first 2 months of lactation
pathogen risk factors
viability - contagious more susceptible to disinfection
virulence -
colonzing ability
toxins
pathogenesis of mastitis
invasion - pathogen moves from teat end in to milk in canal
infection - pathogens multiply rapidly and invade mammary tissue, maybe toxin release
inflammation - clinical mastitis, mamyeb udder changes, milk changes
severity and duration of mastitis related to
promptness of neutrophil migratory response and bactericidal activity
if bacteria survive initial host repsonse, the inflam continues and neutrophils move to alveolar lumen, damagaing tissue and decreasign milk production
severity of mastitis
paracute - severe inflam, swelling, heat, pain, marked systemic reaction. can be fatal
acute - severe inflam without marked systemic reaction
subacute - milk inflam with persistent abnormality in milk
cchronic
duration of mastitis
short - E.coli, Klebsiella
recurrent - S.aureus, S. dysgalactiae
persistent - M.bovis, S.agalactiae
risk factors and pathogenesis of S.aureus mastitis
Hornflies in heifers
colonisation of teat epithelium and adherence. prodution of b toxin, coagulase and extracellular lipopolysaccharide layer biofil. formation of microabcsesses and conversion to L form which is not susceptible to antimicrobials
sigsn of S.aureus mastitis
severe systemic signs, anorexia, sudden onset and highly fatal
gangrene, secondary infections, sloughing of whole quarter
chronic form = atrophy, decrease milk, high SCC, most common form
treatment of S.aureus mastitis
ampicillin has low bacteriologic cure
L- form = lifetime infection, B lactase production
stop lactation - flunixin, atb, iodine
fluids and electrolytes
prevention of S.aureus mastitis
cull infected cows, good milking hygiene, dry therpay on all cows, milk infceted last
Mycoplasma mastitis transmission
poor milking hygiene
hematogenic spread betwen quarters and colonisation of respiratory or urogenital epithelium
in heifers - systemic infection and then localisation in udder
signs of mycoplasma mastitis
classic = severe clinical mastitis in multiple quarters of multiple cows with little to no systemic signs
purulent discharge, decreased milk, otitis in suckling calves
colostrum/cheese curd looking secretion, milk has fine, flakes, purulent but no large clots
almost complete stop of lactation
treatment of mycoplasma mastitis
cull the cow
control of mycoplasma mastitis
prevent entry of infected cows
cull affected cows
vaccination
Streptococcus agalactiae mastitis
sign s= individual, repeat episodes of acute inflammation, watery milk with clots
diagnosis = milk culture and LATEX agglutination test
treatment = IMM penicillin, maintain good milk levels for 72h
blitz therapy = treat all cows then have good sanitation
risk factors for coliform mastitis
low SCC
decreased neutrophil function in puerperium
inadequate vit E and Se levels
wet bedding
highest rate of E.coli mastitis
2 weeks before and after calving
pathogenesis of E.coli mastitis
proliferate and produce endotoxin. there si a large change in vascular permeability and edema of gland
in recently calved cows there si a delay of neutrophil diapedesis (no chnage in milk but bad endotoxemia)
outcome of E.coli mastitis depends on
neutrophil response
e.coli mastitis out comes depending on neutrophil response
rapid - mild undetected clincial disease, self curing, milk negative for bacteria
failing - release fo endotoxin and highly fatal endotoxemi
delayed - acute clinical mastitis, progressive inflammation and permanent loss of secretory function
latency of e.coli
can remain in neutrophils. new infection occur in last 30d of dry off but remain latent til parturition and then there is peracute mastitis
peracute e.coli mastitis
severe toxemia, fever, increased HR, flaky, watery yellow milk, uremia, acidosis, death in 6-48h
acute e.coli mastitis
swollen gland, watery milk with small flakes
recover in days if good treatment
chronic e.coli mastitis
repeat episodes of subacute
subclinical e.coli mastitis
1 - only abnormal secretion
2 - 1 and abnormal gland
3 - 2 and abnormal cow
treatment of e.coli mastitis
mild - B lactasmase resistance atb IMM in lactation
severe - cephalosporins, IV oxytetracycline, IMM for 3-5d, fluids, elctrolytes, NSAIDs
control of e.coli mastitis
hygienic environment
vaccine in dry period to decrease incidence of clinical disease
T.pyogenes mastitis
summer mastitis as associated with biting flies
T.pyogenes mastitis is most common in
dry cows or pregnant heifers
signs of T.pyogenes mastitis
peracute- 1 hot swollen front quarter, watery with clots durign purulent secretion, lamness, swollen hind joints, ABSCESSES
diagnosis of T.pyogenes mastitis
summer
abscesses
culture milk
treating T.pyogenes mastitsi
affected quarter almost always lost
poor repsonse to IMM oxytetracycline
