Exam 2 Review Flashcards
what is the vomeronasal organ? describe it including function and anatomy/location
- accessory olfactory organ
- under the nasal mucosa; connected to two ducts on the top of the mputh just behind the upper lip
- function: transmit info from pheremones to hypothalamus in Flehman response (sensory neurons in VNO evaluate from air wafted into it)
describe the hormonal changes that occur during the follicular phase of the mare estrous cycle including tissue structures involved
- GnRH from hypothalamus acts on anterior pituitary gland to produce FSH and LH
- FSH responsible for follicular recruitment and development in ovaries
- LH does follicular maturation, surges to induce ovulation, and CL development
how is S. vulgaris damaging to the cardiovascular system
- larvae migrate to anterior mesenteric artery
- once there, they disrupt blood flow, form thrombi, and irritate artery walls, further constricting blood flow
- as irritiation continues, artery walls can balloon out
- thrombi can dislodge and become embolie that travel around the circulatory system, disrupting bloow flow and causing damage as they migrate
name two models of artifical vaginas used with stallions; which is most popular and why?
- colorado
- missouri
missouri is most popular because it is not as heavy as colorado, which can weigh up to 25 lbs and is hard to maneuver during semen collection
what is the normal TPR for an adult horse?
temp: 99-101 F
pulse: 28-44 beats per minute
resp rate: 10-24 bpm or 8-16bpm
what are the common risk factors for heaves? (3)
- horse is six years or older (avg onset at 9 yrs old)
- horse has prolonged repeated exposure to dusty stall or dusty feed with poor ventilation
- horse if fed or bed with grass or cereal materials/feed
in the mare, what is meant by maternal recognition of pregnancy; what happens?
the presence of the cocneptus prevents luteolysis, decreases receptors for PFG2a, and block release of PGF2a; this is possibly related to the conceptus secreting enzymes for synthesis of prostaglandins E and F and pregnancy recognition factor
what are the 2 common clinical signs associated with laryngeal neuropathy that msot owners present to the veterinarian while taking a history of the horse?
exercise intolerance and inspiratory dyspnea (roaring) during exercise
what are endometrial cups? describe them
outpouchings of endometrium in the gravid uterine horn; these reach max size at day 70 of preg; and are sloughed by day 130; they secrete equine chorionic gonadotropinm, which aids in maintaining the CL and also aids in development of supplementary CLs, both of which secrete progesterone for preg maintenance until the placenta takes over for producing progesterone
what are the routine parameters to be evaluated for semen? include normal ranges
- volume: 25-100mL per ejaculate
- concentration: 30-800million sperm/mL
- motility: 60-100% progressively motile
morphology: 70-80% morphologically normal
what are the general effects of estrogen in the mare?
- initiates standing heat
- dilates the cervix and cuases it to secrete mucus
- changes the environment of the oviduct for favorable sperm passage by increasing motility and secretory activity
does estrogen affect the stallion? if so how?
yes; it aids in accessory sex gland function and in maintaining libido via feedback to regulate LH release from the anterior pituitary gland
describe recurrent airway obstruction
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describe exercise induced pulmonary hemorrhage
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describe laryngeal hemiplasia
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describe photoperiod in stallions
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describe S. vulgaris
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how long is spermatogenesis in stallions?
57-58 days
in the stallion, what regulates the leydig cells of the testis?
LH
what do they leydig cells in the testes of the stallion produce as regulated by LH?
estrogen and testosterone
describe the surgery to treat laryngeal hemiplasia in horses
ties back the arytenoid cartilage to improve air flow
give an example of a bronchodilator used for heaves?
clenbuterol (ventipulman)
describe cryptorchid testis
one that stays in the abdominal cavity or inguinal canal
what is a diuretic that is routinely given before exercise in horses with EIPH?
lasix (furosemide)
where are spermatozoa produced?
in the seminiferous tubules of the testes
give a symptom of chronic parasitism; then give one for acute parasitism
chronic: lethargy
acute: diarrhea
describe equine roundworms
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describe the sperm system
spermatogenesis begins in the seminiferous tubules of the testes. spermatozoa then travel through the straight, rete, and efferent tubules before entering the duct of the head of the epididymis, which concentrates spermatozoa as they mature into motile, viable sperm and are stored in the tail of the epididymis until shortly before ejaculation, where they mix with secretions from the prostate, seminal vesicles, and bulbourethral glands before ejaculation and exit from the penis
describe the possible etiologies for EIPH
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