Equine Reproduction Flashcards
1
Q
When does the mare cycle
A
during times of long daylight
2
Q
What kind of cycle do mares have
A
Seasonally polyestrous
cycle during times of long daylight
3
Q
How long is the mare’s cycle
A
21-23 days
Estrus: 5-7 days where she is receptive. Stands for stallion, leans, lifts tail, and urinates
Diestrus: 14-16 days, not receptive, walks away, ignores stallion, swishes tail, ears back, bites or kicks
4
Q
What kind of behavior changes is seen with estrus in the horse
A
5-7 days where she is receptive. Stands for stallion, leans, lifts tail, and urinates
5
Q
What kinds of behavior changes is seen with mares in diestrus
A
14-16 days, not receptive, walks away, ignores stallion, swishes tail, ears back, bites or kicks
6
Q
what is a speculum used for
A
to examine the vagina and posterior cervix
Determine
1) Stage of cycle
2) Abnormalities
3) Obtain culture sample
4) AI for mares in which standard AI insemination is difficult
7
Q
What 4 things might you use a speculum exam for
A
1) Stage of cycle
2) Abnormalities
3) Obtain culture sample
4) AI for mares in which standard AI insemination is difficult
8
Q
Cervix characteristics of a mare during estrus
A
Relaxes and softens
1) Open
2) Edema
3) Rests on ventral vagina
4) Clear mucus
5) Pink
9
Q
Cervix characteristics of a mare during diestrus
A
Tightens and closes
1) Closed
2) Protruding into vagina
3) Mucus tacky and dry
4) Pale pink coloration
10
Q
Upon a speculum exam you see that the cervix is resting on the ventral vagina, is pink with clear mucous, and have edema. What stage of her cycle is she in
A
Estrus
11
Q
Upon a speculum exam you see that the cervix is protruding into the vagina, closed, mucus tacky and dry with a pale pink coloration. What stage of her cycle is she in
A
Diestrus
12
Q
area of vulvovaginal fold that may contain circular opening or strands of tissue
may occasionally be complete
A
persistent hymen
13
Q
what can be a consequence of palpating mares
A
Rectal tears
14
Q
Why might rectal tears occur when palpating a mare
A
1) Improper technique
2) Distractions
3) Weakened tissue
15
Q
How might you be able to prevent the mare from excessive straining or movements to prevent rectal tears
A
Confine
Entertain
Twitch
Sedate
Buscapan
Palpate back- never push forward into the rectum
Always examine sleeve for blood after palpation
16
Q
provides movement of the rectum during palpation
A
Mesorectum
17
Q
Steps of tract palpation
A
1) Identify bifurcation of uterine forns
2) LSide hand along uterine horns to ovaries
3) Palpate cervix last
(1= tightly closed, 3 = wide open)
18
Q
Can you palpate a CL on a mare?
A
N- the CL is internal to the ovary cannot reliably palpate
19
Q
How many follicles do mares usually ovulate
A
single ovulation usually
*increases 3-5mm in diameter per day during estrus
about 45 mm diameter before ovulation
20
Q
How much does the mare’s follicle increase each day of estrus*
A
about 3-5 mm in diameter per day during estrus
about 45mm diameter before ovulation
21
Q
How can you measure follicle size on ultrasonography *
A
there are 10mm (1cm) increment marks on the top of the ultrasound
mark will point to front of transducer (be aware of direction)
22
Q
The bladder is ______ to the pelvis and _______ to the uterus
A
anterior to pelvis
ventral to the uterus
23
Q
What does the bladder look like on ultrasound
A
Echogenic (grey) urine
24
Q
What are the ultrasound goals of the uterus in the horse
A
1) Endometrial edema
2) Stage of cycle- edema during estris
25
What causes edema within the uterus
Estrogen
*most pronounced in early estrus
26
When is edema most prominent in the mare
early estris
estrogen causes edema within the uterus
27
What can you tell about the mare's ovary on ultrasound
Identify follicle and corpus luteum
28
How many waves do mares have
Most have 1 wave
however some mares have two waves but as long as there is a CL, the follicles will grow and then atresia- regression if ovulation doesnt occur
29
What do mare's follicles look like on ultrasound
1) Round
2) Black (anechoic)
3) Multiple follicles will be present on ovaries- growing and regressing
4) Dominant (ovulatory) follicle- grows 3-5mm per day, usually single ovulation at 45mm diamter
30
release of the oocyte
occurs rapidly
will see:
ultrasound- irregular shape and defined border
and
palpation: pain and softening
right before
Ovulation
31
How do you determine ovulation in the mare
difficult to determine/image with ultrasound
grey (similar appearance to stroma), no defined borders, can have central fluid
palpating edema, soft area, indentation, pain
32
How does the follicle shape size change prior to ovulation
irregular shape with a defined border
33
What will you see on ultrasound after a mare's ovulation
difficult to determine/image with ultrasound
grey (similar appearance to stroma), no defined borders, can have central fluid
34
What does an early luteum look like on ultrasound
Echoic: moderate to bright grey or white
easy to image
can have central trabeculated area
35
What will the mare's corpus luteum look like on ultrasound
Moderate gray
can have trabeculated center
36
When is the mare's CL considered mature
5 days
37
What does the corpus albicans (CL regression) look like under ultrasound in the horse
Small
Black ring
often bright center
14-16 days for natural luteolysis
prostaglandin administration
38
How is the mare's cycle manipulated
1) Induction of ovulation
2) Lysis of CL- short cycle
3) Time, shorten or synchronize cycles
39
What is the criteria for induction of ovulation in the mare
1) 35mm follicle
2) Estrus: Uterine edema, relaxed tone uterus, open cervix, estrus behavior
40
What drugs can you use to induce ovulation in mares
1) hCG
2) GnRH analogs- ie SucroMate
41
hCG for inducing ovulation in the horse
acts at the follicle
mare will ovulate 36 hours later
42
How long after hCG administration will the mare ovulate
36 hours later
43
What is a downside to hCG to induce ovulation in the mare
reduced response with repeated use in the same breeding season
44
a GnRH analog used to induce ovulation in the horse
SucroMate (Deslorelin acetate)
causes pituitary release of endogenous LH
45
What is the mechanism of action of SucroMate
causes pituitary release of endogenous LH to induce ovulation about 40 hours later
46
How long does it take for SucroMate to induce ovulation in the mare after injection
about 40 hours
47
What induces ovulation in the horse quicker?
SucroMate or hCG
hCG- 36 hours
SucroMate- 40 hours
48
What is the trade name of Deslorelin acetate
SucroMate
-used to induce ovulation in the horse
49
will cause the lysis of the CL and return to estrus in mares
short cycle about a week
prostaglandin
50
The CL is not fully susceptible to the luteolytic effects of prostaglandin until ________________ in the mare *
until 5 days after ovulation
51
What are different prostaglandins you can use to short cycle a mare
1) Cloprostenol (Estrumate) - most often used, 250ug, IM, prostaglandin analog
2) Dinoprost (Lutalyse) - 5-10mg, IM, native prostaglandin, more side effects
52
Cloprostenol in the mare is a ___________ used to ________ and has the trade name of _______
prostaglandin used to short cycle (lyse CL)
trade name of Estrumate
53
What is the trade name of Cloprostenol
Estrumate
54
What is the trade name of Dinoprost
Lutalyse
55
Dinoprost in the mare is a _____ used to _______ and has the trade name ______
prostaglandin
short cycle (lyse CL)
Lutalyse
56
________ is a synthetic prostaglandin while ______ is a native prostaglandin used to lyse the CL in horses, only susceptible about 5 days after ovulation
Cloprostenol (Estrumate) = synthetic
Dinoprost (Lutalyse) = native
57
What are the side effects of prostaglandins in the horse
Short duration
sweat
scour
mild colic
Dinoprost (Lutalyse) has more side effects than Cloprostenol (Estrumate)
58
Does Dinoprost (Lutalyse) or Cloprostenol (Estrumate) have more side effects
Dinoprost (Lutalyse)
Short duration
sweat
scour
mild colic
59
Following luteolysis, most horses will return to estrus in _____ days and ovulate in _______
Estrus in 2-5 days
Ovulation in about 9 days, varies depending on follicle sizes
if administer with smaller (~20mm) diestrus follicles, most mares will be ready to be breed in 1 week
often, ovulation induction in 5-6 days
60
What occurs if you administer prosaglanidns in a horse with smaller (~20mm) diestrus follciles
if administer with smaller (~20mm) diestrus follicles, most mares will be ready to be breed in 1 week
often, ovulation induction in 5-6 days
different from the normal 9 days *
61
What occurs during the winter in mares
Winter anestrus
1) Does not cycle
2) Minimal ovarian activity
3) Flaccid uterus
*More pronounced in colder climates and further from equator
62
How is the horse a seasonal breeder
1) Increase in day length stimulates the hypothalamic-pituitary-ovarian axis
2) Spring (vernal) transition: 2-3 months in length, FSH increases prior to LH; waves of follicular growth (increasing follicle diameters, no ovulation)
Estrus - long, variable periods
63
What occurs during the spring transition in the horse
2-3 months in length
FSH increases prior to LH causing waves of follicular growth
-Follicles increase in diameter but no ovulation
-Estrus is long and variable periods
-Most mares naturally ovulate in April
64
What commonly indicates that a mare is ready to ovulate after the spring transition
Shedding at the first ovulation
65
What is the natural breeding season of the horse
Varies with location
April to September
Longer as closer to the equator
66
What is the artificial horse breeding season
February 15- July 15
"January 1 considered birth date"
-a foal born anytime during the year is considered 1 year old on January 1 of the following year
67
How do you hasten ovulation because clients want foals early in the year
Artificial photoperiod
14 to 16 hours of light
~2months
Lights in December to breed in February
Also pertains to foaling mares and stallions (for max sperm output)
68
Horses kept under lights all year can eventually _____
go into an anestrous period
69
Is the stallion a seasonal breeder
yes but unlike the mare there is no cessation of sperm production
-Low number sperm during short daylight
70
How does the stallion produce less sperm in the winter
reduced GnRH secretion leading to lower LH and testosterone
*Artificial lighting- same as mare, will alter timing of peak sperm Feb 15-July
71
T/F: you can influence the stallion to artificial light, just like the mare to alter the timing of peak sperm
True
72
When do male horses hit puberty
about 2 years
generally start to breed at 3 year
sexually mature at 5-6 years
*Sperm production increases until 9-16 years
73
In the stallion, sperm production increases until about
9-16 years
74
stallion sexual behavior
libido is often a limiting factor
hormonal component
environmental factors: stallion handling, housing, frequent using
75
What is total scrotal width of a stallion
about 9.5-11.5cm
76
What is evaluated in the breeding soundness exam of a stallion
1) Scrotal width (9.5-11.5cm)
2) Libido and mating behavior
3) Cultures of urethra, seme
4) Semen evaluation 4-12 billion
5) Progressive motility
6) Sperm morphology
77
What are steps of artificial insemination
1) Restrain mare, wrap tail, wash with mild soap and rinse 3X or until clean
2) Introduce pipette into vestibule
3) Move hand dorsal above vulvo-vaginal fold to avoid urethral os
4) Pass through cervix and deposit semen into uterine body
78
What are the different types of semen used for insemination
fresh, cooled, and frozen
79
What type of semen has the best survivability
fresh (2 days) >
Cooled (1 day) >
Frozen (12 hours) >
80
What type of semen has the best fertility
fresh > cooled > frozen
81
What are the temperatures of the different kinds of semen
Fresh: room/body temp
Cooled: 5C
Frozen: Liquid nitrogen
82
What is the sperm dose for different kinds of semen in horse
Fresh: 500million
Cooled: 1 billion
Frozen: 800 million
83
when a mare is bred naturally
live cover
84
What is the longevity of different kinds of semen
Live cover: 2 days
Fresh AI: 2 days
Cooled: 1 day
Frozen: 0.5 day
85
What is the criteria for inducing ovulation in a mare ***
1) 35mm follicle
2) Endometrial edema
3) Estrus
4) relaxed uterine tone
5) Open cervix
Induce with hCG or GnRH analog: 1.5-2 days until ovulation
86
The equine oocyte will remain viable for ____- hours after ovulation
less than 12 hours after ovulation
Want to breed 6-8 hours after ovulation
87
you should breed the mare within _____ hours after ovulation
12 hours (aim for 6-8 hours)
the equine oocyte is not viable after 12 hours
88
How do you diagnose early pregnancy in the mare
12-16 days: initial detection
16: Return to estrus
25: Heartbeat
35: Cup formation
Checked later for mare management
89
When is palpation for pregnancy detection in the mare able to be done
25-35 days
earlier will feel toned uterus and tight cervix
ventral bulge at base of uterine horn
careful not to confused with bladder (60-90days): tight cervix and ovaries pulled central
90
when will a mare return to estrus if she is not pregnant
in about 16 days
91
maternal recognition of pregnancy in the mare
migration of embyo- uterine contractions
-prevents the release of prostaglandin and luteal regression
Until 17-19 days (depends on uterine and vesicle size)
92
when searching for an embryo in the mare, how do you ultrasound?
move across the horse and scan cross-section until you get to the body and then turn the probe to scan down
go back and forth to look for it
93
when does the mare's embryo proper begin to form
at about day 25- indicator of viability
"Heartbeat"
94
What does the chorionic girdle produce
ecG or PMSG on day 35 of gestation (act like FSH/LH)
95
When is eCG produced from the chorionic girdle
on about 35 day of gestation
96
When can you detect the pregnant mare's fetal heartbeat
day 25 of gestation
97
When do endometrial cups begin to form
Day 35
98
What occurs during the motility phase of the equine embryo
the embryo rapidly increases in size, round, and changes locations
99
100
What is importance of endometrial cups
important for equine pregnancy maintenance
specialized cells from the placenta that migrate into endometrium
produce eCG (PMSG)
maintained until programmed cell death 35-120 days
101
when do endometrial cups typically go away
day 120
individual variation
regardless of fetal survival after uterine invasion
prevents rebreeeds of mare until about 4 months from initial conception if pregnancy is lost after cup formation. failure of normal ovulation
102
secondary corpora lutea in the mare
large ovaries and luteinized structures that form during gestation
increase progesterone until they eventuall regress
103
If you do a blood assay and the mare is positive for eCG, what does this tell you
there are endometrial cups present. The mare is either pregnant or was pregnant
104
When might you have a false negative on eCG assay
the time of sample collection
endometrial cups are typically present from day 35-120 of the mare's gestation
105
When might you have a false positive on eCG assay
fetal death after cup formation
however, most pregnancy losses occur prior to cup formation
106
What maintains the mare's pregnancy after 120 days
placental progestins
-minimal ovarian activity
107
Can you measure progesterone for mare's pregnancy diagnosis
NO- not diagnostic, not progestins
variable results
depends on the cross reactivity
108
When do plancental progestins take over to maintain the mare's pregnancy
about 120 days (90-150)
109
Why might a pregnant mare act "studdy" during pregnancy
Fetal gonads increase in size in mid gestation but regress in late gestation
-Testosterone is produced (Colt or filly)
-can induce behavioral changes in the mare (more aggressive or stallion-like behavior)
110
How might you use estrogen-based pregnancy tests in mares
Estrone and estradiol are produced by the fetal-placental unit increasing at about day 90 of gestation
-estone sulfate initial increase on day 45 of gestation
from ovaries of mares stimulated by eCG
111
What stimulates the estrogen seen to increase around day 90 of gestation in the mare
estrogens are produced from the ovaries of mares
-stimualted by eCG
112
When can you sex the mare's fetus
After 60 ays - genital tubercle is identified
113
How do you tell the bladder vs pregnancy
1) allantoid fluid is anechoic
2) ovaries are pulled central
3) Cervix is tight
*Identify bladder or nonpregnant uterus
*Fetus and umbilical cord may be hard to image
114
what does allantoid fluid look like on ultrasound
Anechoic
115
Most twin pregnancies in the mare will
have a reduction with 60% resulting in live single deliveries
1% have two live foals but it is undesirable as insufficient uterine capacity
116
Most twins in a mare are caused by
two ovulations (identical twins are rare but seen more with ICSI programs)
117
When should you do manual reduction of equine twins
12-15 days
118
If you identify twins in the mare what should you do?
Manual reduction: 12-15 days - squish one of embryos after separating
Abortion: optimally before 35 days and formation of endometrial cups, repeated doses of prostaglandin
-Later procedures are less successful
119
How do you do abortion in a mare with twins
optimally before 35 days and formation of endometrial cups, repeated doses of prostaglandin
120
post fixation twins
outcome often relative to position and size
end pregnancy by 35 days to rebreed
-endometrial formation after 35 days
-will not return to estrus after cups form until regression
-probable bad outcome without intervention
Cessation of pregnancy with prostaglandin
121
What is the difference between bilateral equine twins vs unilateral equine twins
Bilateral: >80% maintain after 40 days
Unilateral: Most reduce to singleton- dissimilar size and location of cord
122
Early pregnancy maintaince in equine, progesterone needs to be
>4ng/mL
initial pregnancy maintenance from primary CL then secondary CLs
123
Should you supplement the mare's pregnancy with progesterone
precaution, for mares with
history of embryo loss
older, problem mares
seen when repro exam
-small ,regressing CL
-poor tone to uterus or cervix
-endometrial edema
use short acting or long acting progesterone (daily vs weekly administration)
Altrenogest (ReguMate)- supplement until placental maintenance (120days)
124
Why is Altrenogest nice
because you can determine the mare's endogenous progesterone
-not detected by progesterone assays
-supplement until placental maintenance (120 days)
125
What is another name for Altrenogest
Regu-Mate
126
Why might an embryo be lost?
-luteal insufficiency
-uterine inflammation
-uterine fibrosis
-embryo defects
-delayed fertilization
-embryo insult
-infectious/diseasese/ misc
127
How long is the mare's gestation *
Normal: 340 days
Range 320-260 days
Premature <320 days
128
What species has a gestation of 340 days but can range from 320 days
the horse
129
foals are considered premature when they are before before
320 days of gestation
130
What are some preparation need to be made for foaling
1) Move to foaling site about 1 month prior
2) Vaccinate- colostrum (Tetanus)
3) Open the caslicks
131
What are some signs that a mare is going to foal
1) Mammary gland development: 2-6 weeks
2) Ventral edema
3) Dropped abdomen: 2-3 weeks
4) Perineal relaxation: 1-3 weeks
5) Teat engorgement: 7-10 days
6) Mammary electrolyte changes
7) Waxing *: colostrum dripping 48-72 hours
8) Elongation of vulva: 0-24 hours
9) Behavior changes
132
What occurs during Stage I parturition in the mare
1) Uterine contractions: restless or nervous, frequent lying down, pawing, patchy sweating, running mild, dripping milk
2) Rupture of the chorioallantoic membrane
1-4 hour: foal repositioning
133
What marks the end of stage I of labor
rupture of chorioallantoic membrane
134
What occurs during Stage II of labor in the mare
active straining
appearance of amnion
birth of foal- front legs and nose, one foot in front of the other and nose
last 10-60minutes
135
what do you want to do to the foal once they are expelled from mom
1) clear nostrils
2) Dip umbilical cord (0.5% chlorhexadine or 1 part 2% novalsan solution and 3 parts distilled water)
136
What is stage III of parturition in the horse
Expel placenta via uterine involution and myometrial contractions (takes 15min to 3 hours (average 1.5 hours)
Mild colic signs
Retained if not passed in 3 hours
evaluate the placenta to make sure all is there
137
In the horse, the placenta is considered retained when it is not passed in
3 hours (average time is 1.5 hours)
tip of horn is most common spot, evaluate horn
138
premature separation of the placenta happens when
the chorioallantoic membrane fails to rupture and the placenta separates from the endometrium
*emergency condition - loss of blood supply to the fetus
139
What is red bag delivery
when the chorioallantoic membrane fails to rupture and the placenta separates from the endometrium
*emergency condition - loss of blood supply to the fetus- hypoxia, open membrane immediately and prompt delivery of foal and oxygen
140
the portion of the placenta in the mare that does not have microvilli because of contact to the cervix
cervical star
141
the most common early postpartum problem in the mare is
retained placenta - can be the full placenta or a tip of the nonpregnant horn
142
How do you prevent retained placenta
examine the placenta after foaling
have the client remove from stall and save for evaluation
143
What are symptoms of a retained placenta in the horse
fetid, red-brown discharge
depression
anorexia
fever
from
metritis and systemic issues- endotoxins, systemic endotoxemia
144
How do you treat retained placenta in a horse
1) Oxytocin
2) uterine lavage and treatments
infusion of fluid into allantoic space
3) Additional treatments
systemic and uterine antibiotics
uterine lavage
nsaids
laminitis support
*Be careful not to apply too much pressure, dont want to rip out
145
What is the interval to ovulation after parturition in the horse
short interval- based on season and lights, can be 7 days
often best to assure at least 9 days to ovulation after foaling if wanting to breed on foal heat
146
the first heat cycle a mare goes through after foaling and a manager's first opportunity to breed her. It typically occurs six to 12 days after foaling.
foal heat
often best to assure at least 9 days to ovulation after foaling if wanting to breed, endometrium needs to recover
147
What are some considerations in breeding a postpartum mare
1) often best to assure at least 9 days to ovulation after foaling if wanting to breed on foal heat
-mares may cycle earlier in summer, endometrium needs to recover
2) Confirm no discharge or signs of uterine fluid
3) If needed, allow to ovulate then short cycle for breeding
148
What issues might affect a mare's ability to get pregnant
-Systemic health
-Endocrine issues (Equine metabolic syndrome), PPID (pituitary pars intermedia dysfunction)
-Stress and pain
-Aging
-Drugs and diet
149
Why might a mare have no follicular growth
1) Winter anestrus- change hemisphere or other alter light exposure
2) Aging
3) Endocrine problems
4) Tumors
5) Chromosomal abnormalities
150
Why is the most common tumor of the mare reproductive tract
granuloma cell tumor
-leads to behavioral changes, stallion characteristics
-usually do not cycle on contralateral ovary
151
T/F: horses with granulosa cell tumors usually do not cycle on contralateral ovary
True
152
How do you diagnose granulosa cell tumors in mares
Endocrine paramaters:
Tumor profile- testosterone, inhibin
and AMH
153
What are reasons why a mare might try to mount another mare
1) Pregnant
2) Granulosa Cell Tumor
154
What do granulosa cell tumors look like grossely
typical cystic appearance
155
How do treat granulosa cell tumors in horses
surgical removal- they are able to be bred again with a single ovary
156
Are mares with granulosa cell tumors fertile
most mares will cycle and be fertile
157
What are other differentials for granulosa cell tumors in mares
1) Teratoma- variety of tissue types, echogenic and cystic areas
2) Cystadenoma- usually unilateral, does not affect the contralateral ovary
*You will not see any behavioral changes and will have an active contralateral ovary with these
158
How might you diagnose anovulatory follicles in horses
ultrasound- spot, strands in the follicle
typically occur in older mares in the spring and fall transition
159
Anovulatory follicles typically occur in mares that are
typically occur in older mares in the spring and fall transition
160
What are hemorrhagic follicles
follicles that fail to ovulate
increase in size
blood and fibrin in the antrum
oocyte trapped
regress over time
may respond to prostaglandin
161
the oocyte must be competent for fertilization and embryo development, what might affect the oocyte
age, heat, and stress
162
Fertilization in the mare occurs in the
ampulla
sperm reservoir at the UTJ or isthmus
163
a developmental remnant that is generally not clincially significant
may be confused with a follicle
palpation important to differentiate
may be large
Paraovarian cyst
164
hydrosalphynx
a fluid accumulation in the oviduct
rare unilateral
165
What are occluding masses to the oviduct
gelatinous with fibroblast leading to occluding of the oviduct
undiagnosed reproductive failure
difficult to confirm
treat with oviduct flush and/or PGE2
166
What are barrier to the uterus
1) Cervix
2) Vestibular sphincter
3) Vulva
167
What is the normal vulva confirmation of a hare
1/3 of vulva above the brim of the pelvic
2/3 below the brim of the pelvis
168
poor vulva conformation predisposed the mare to
uterine inflammation or infection and reduced fertility
169
common cervix issues in the mare
-anatomical defect
-fibrosis
-adhesions
-tears
*Cervical problems can be difficult to correct
170
A small amount of intraluminal fluid is normal in ______ but not normal in ______ of the mare
Normal in estrus
Not normal in diestrus
*grey appearance on ultrasound
171
What intraluminal apperance of the uterus is bad news in the mare
grey appearance - cellular debris
*Any fluid in diestrus is bad news, but if clear in estrus, it is okay
172
What causes uterine cysts
blocked lymphatic vessels- indication of scar tissue
173
What do uterine cysts look like on ultrasound
often multilobulated
variable shapes and locations
can be pedunculated or within uterine tissue
*Be careful to not confuse with embryo
cyst will not change location, size, or have a heartbeat
174
How do you differentiate uterine cysts from embryos
cyst will not change location, size, or have a heartbeat
175
What might cause pneumouterus or pneumovagina
poor perineal conformation
can also observe air within tract after AI or other procedures, try to prevent
176
What is the issue with pneumouterus/pneumovagina?
can be an irritant- prevent pregnancy or introduce infection
177
What does pneumouterus/pneumovagina look like on ultraound
hyperechoic areas- dots or line (reverberation)
178
types of foreign bodies that can occur in the reproductive tract?
-mummified fetal bones
-culture swab tip
-marbles
Diagnosis and Tx
-hyperechoic- shadow
-removal
179
What is one of the most common cocci found in mare's repro tract
Strep equi sbsp zooepidemicus
180
Uterine biopsies assess _____
1) Health of uterus
2) Glands- number and activity
3) Scar tissue
4) Cell types- inflammation and infection
*No nerve endings, cant hurt mare
181
Most common bacteria associated with endometritis in the mare
1) Streptococcus equi ssp zooepidemicus
2) Escherichia coli
3) Pseudomonas aerginosa
4) Klebsiella pneumoniae
also yeast and fungus
182
What mares are susceptible to endometritis
1) delayed uterine clearance
2) fibrotic cervix
3) poor perineal conformation
other causes: semen, contamination, techniques
183
How do you diagnose endometritis in the mare
1) failure to conceive
2) early return to estrus
3) vaginal discharge
4) fluid within lumen of uterus- grey on ultrasound
5)culture
6) cytology
184
How do you treat endometritis in mare
Treat predisposing problems
Prostaglandin to return to estrus
, uterus more resistant to infectious agents, cervix open to allow removal of debris
185
What are ecbolics
induce uterine contractions and promote clearance
1) oxytocin (10-20 IU): 30-60min contractions, 4 hours to reset receptors
2) Prostaglandin: 250ug cloprostenol (Estrumate): 2-4hours of contractions, could affect early luteal formation or induce ovulation
186
removal of dead cells and infectious organisms using LRS or saline solution of the uterus
remove debris prior to antibiotic treatments
1 L at a time, repeat until clear
uterine lavage
187
Do you want to do a uterine lavage before or after antibiotic treatments
remove debris prior to antibiotic treatments
188
For endometritis, antibiotic choice is based on
safety of antibiotic prior to use and based on culture and sensitivity information
-ampicillin, ceftiofur, gentocin, ticarcillin
189
What antibiotic is not for intrauterine use in horse
Baytryl
190
What antibiotic needs to be buffered with bicarb before intrauterine use in the mare
Gentamicin
191
T/F: mares with pyometra are systemically ill
FALSE
192
What is the prognosis of pyometra in mares returning to fertility
low prognosis for return to fertility
193
What is mating-induced endometritis in the mare
transient inflammatory response is normal
peaks about 8 hours after breeding
nromal mare will clear inflammation but some mare are susceptible to sustained inflammation
check uterus after AI/breeding
treat with ecbolic and/or lavage
194
degenerative changes in the uterine lining of the mare that can affect embryo survival and placental function
consequence of aging, inflammation, insults
not correctable- pregnancy failure
uterine fibrosis
195
How do you diagnose uterine fibrosis
uterine biopsy
196
urine poolin the the uterus in mares is common in
often older or postpartum mares with sunken uterus
pool urine in front of cervix, urine enters uterus in estrus when cervix is open
manage with time, weight and exercise
surgery
caslick is not a corrective surgery
197
T/F: A Caslick treats uterine pooling in a mare *
False- it is not a corrective surgery
198
It is April 1 in Colorado, and you go to Maybelle Mayberry’s house to check her mare, Sassy. Sassy is out in a pasture during the day; but in the evening, Ms. Mayberry puts her into a large pen with lights on one side. She has done so since January 20. She wants to breed her asap to get an early foal next year. Sassy is in good body condition, but she still has a long, winter hair coat. Ms. Mayberry says that Sassy has been showing signs of estrus during the last week to a gelding. The owner would like to get Sassy bred this week. Ultrasound images show Sassy’s uterus and left and right ovaries. What will you tell Ms. Mayberry?
Sassy is still transitional and not yet ready to breed this year. While there were lights in the pen, the pen was not lighted evenly, so Sassy may have been standing outside of the lighted areas. Consequently, she did not respond to the artificial lighting. This is supported by her long, winter hair coat.
199
Because of the artificial breeding season for horses, many mares are put under lights, so they foal in the winter. To get foaling mares to cycle early in the year after foaling, they also have to remain under artificial lighting. How does artificial lighting affect the stallion?
Increase daily sperm production earlier in the year.
200
Dash Me Too is to be bred to a local stallion. When you palpate her, you feel a large follicle on her left ovary; but her cervix is closed, and her uterus is toned. See images of Dash's ovaries and uterus. Please select the most appropriate statement.
Dash is in diestrus with a larger follicle. Either wait for her to return to estrus naturally or administer prostaglandin.
201
You are called to Mr. McDonald's farm to check two mares, Bessie and Boogie. Mr. McDonald has seen both mares “teasing” (showing signs of estrus) to his stallion for the last couple of days. He wants to breed them to his neighbor's stallion, and he would like to bring them there today. You ultrasound the mares' reproductive tracts.
Bessie has small follicles on her right ovary. Her uterus is relaxed, and her cervix is open. Her left ovary and uterine horn are imaged below.
Boogie had small follicles on her left ovary. Her uterus is only slightly toned, and her cervix is moderately open. The ultrasound image is of her uterine horn and her right ovary.
Breed Bessie today. Boogie has ovulated, so wait 5 days and give her prostaglandin if the owner wants to short cycle her.
202
a soft tissue structure that guides the movement of the testes during embryonic development
gubernaculum
203
What are the components of the spermatic cord
1) Cremaster muscle
2) Ductus deferens (continuation of epididymis)
3) Testicular artery
4) Pampiniform plexus (veins)
5) Nerves
6) Lymphatics
204
Should you always remove the smaller or larger horse testis first? *
always remove the smaller testis first
205
In horses, you should wait to castrate once ________ *
Both testes are descended and present
confirm with palpation +/- sedation
DO NOT REMOVE ONE TESTIS
206
T/F: monochordism is very rare in horses *
true
207
What is an open castration
a castration where you cut through the tunic and the testi is exposed
208
What is a closed castration
a castration where the tunic is intact and then you cut the cord
209
About 75% of the quarter horses that are cryptorchid have a _____abdominal testis
left
210
What should you confirm when castrating a horse
there are two structures - testi and epipididymis
and both testes are present
211
Is standing or recumbent castration more preferred
really the surgeon's preference but standing is more expensive and dangerous
some breeds like draft horses have a larger inguinal canal so when doing them standing, its hard to keep things from falling down the inguinal canal
212
Is open or closed castration better?
Based on personal preference and size of the horse
213
What kind of peri-operative medications can be given during equine castration *
1) Tetanus toxoid
2) Analgesics
3) Antibiotics? decided by the surgeon based on speed, environment, and experience
214
What supplies are needed for equine castration? *
-Antisepetic for site preparation
-Local anesthetic
-Roll cotton or gauze
-Container for antiseptics and cotton gauze
-scalpel handle and blade
-towel clamp
-hemostat
-needle holder for ligation?
-Metzenbaum scissors
-gauze
-emasculator (Serra triple cut or Reimer Ratchet)
215
During castration, which way should the emasculators should go
NUT to NUT- otherwise you will have a mangled testi
216
What are good sedation drugs for equine standing castration? *
Detomidine + Butorphanol
217
How should you apply local anesthetic for standing castration *
Into the skin and testes (testes takes about 10 minutes to desensitize)
218
How long does it take for the testes to desensitize after applying local anesthetic?
about 10 minutes
219
What drugs should you use for recumbent castration
Xylazine + Ketamine +/- valium
220
How do the drugs for recumbent castration differ from drugs for standing *
Standing: Detomidine + Butorphanol
Recumbent: Xylazine + Ketamine
221
Is local anesthetic worthwhile in equine castration
yes- some evidence for better recovery
222
based upon incising or not incising the common vaginal tunic
open vs closed castration
223
Why might you chose open vs closed castration *
Closed: theoretical that it limits ascending infection because it crushes the vaginal tunic which is continuous with the peritoneum
Open: larger / older horses you can open up the cord to view all the structures like the pampiniform plexus so you can do a double emasculation instead of just a single
224
What kind of castration is best for a young small horse up to 3 years old
Closed castration
225
A single emasculation is (more/less) secure on crushing larger testes and (more/less) secure on crushing small testes
single = less secure on larger testes and more secure on crushing small testes
226
How do you perform a closed castration in a horse
1) incise skin
2) Strip fat from tunic
3) Emasculate
227
An open castration is preferred in a horse
older horses with large testes and spermatic cords
*more secure crushing
228
How do you perform an open castration in a horse
1) incise tunic over testicle
2) extend incision proximally
3) separate vasculature
4) Double emasculate- nut to nut a) vasculature b) tunic/cremaster/ductus
229
What two structures do you hit when doing double emasculation in a horse *
1) Vasculature
2) Tunic/cremaster/ductus
230
What should you tell the owner with equine castration post-operative care
Rest for 1st 24 hours - hemostatsis and swelling
Exercise 7-10 days forced for encouraged drainage
231
What are the common equine castration complications *
1) Hemorrhage- too much if you cant count the drops
2) Excessive swelling
3) Infection
4) Eventration- internal inguinal ring, small intestine, omentum; in certain breeds (draft, mustang, standardbred)
5) Penile prolapse - drug related
6) Hydrocele- fluid within the retained vaginal tunic; varicocele is caused by dilated testicular veins
7) Penile amputation- be careful in youngsters
8) Scirrous cord
9) Peritonitis
232
failure of testicule to descent into the scrotum due to improper gubernaculum function
cryptorchid
233
After 2 weeks of age, the horse's testicles are either in the
scrotum
inguinal canal
abdomen
does not go back and forth
234
in the quarter horse, cryporchidism is more common in the
left testi
235
How do you diagnose cryptochidism in horses?
history
palpation +/0 sedation
Ultrasound- trans-abdominal, transrectal
hCG stimulation- history
236
How do you perform cryptochid castration
Inguinal- high flanker, routine castration, easier in dorsal recumbency, may need to go over external inguinal ring
Abdominal- inguinal, para-inguinal, or laparoscopic
237
What should you do in a horse with unknown castration histroy *
Do not rely on castration incisions
diagnose with palpation- external or rectal, ultrasound, testosterone and/or hCG stimulation
look for stallion-like behavior
238
What is the indication for performing the caslick procedure?
1) older mares
2) multiple pregnancies
3) Loss of condition
4) perineal lacerations
239
What is a normal perineal conformation in the horse *
almost perpendicular to the ground
10-20 degrees
240
What is an abnormal perineal conformation in the horse *
1) <80 degrees from vertical 2) >50% of the vulva above the ischial arch
anus can contaminate the vulva
need for life of the life, remove and replace for breeding/foaling
241
What is needed for the caslick procedure?
Sedation
tail wrap
anti-septic for preparation
local anesthesia with needle and syringe
scalpel (preferred) or scissors
needle holder and suture
thumb forceps
242
How far should you suture when doing a caslicks? *****
down to the level of the tuber ischii
243
What suture pattern should you use for the caslick procedure
simple continuous
244
What suture type should you use for caslick procedure
absorbable or absorbable
245
T/F: you can redo caslick throughout a mare's life
True- just do not remove too much skin/mucosa
a scalpel is much better than scissors at not doing this
246
T/F: you need to remove the caslick before doing AI
false- it does not need to be removed for AI
it does if you are doing live-cover
247
What are the 4 major common complication with equine castration *
which ones do you refer?
1) Hemorrhage- too much if you cant count the drops
2) Excessive swelling
3) Infection
4) Eventration- internal inguinal ring, small intestine, omentum; in certain breeds (draft, mustang, standardbred)
extreme hemorrhage and eventration
248
Should you remove the abdominal or scrotal testi first
abdominal
249
You pregnancy check a mare at 12 days, but she has numerous cysts within the uterus. How do you differentiate the cysts from an embryonic vesicle?
The embryo will grow, and cysts will not increase in size.
The embryo will change positions in the uterus, and the cysts will not.
The embryo is usually round, while cysts are often (but not always) irregular in shape.
