Exam 3 Flashcards
(158 cards)
1
Q
When is the parasite successful
A
If the parasite does not damage or kill its host especially prior to propagation
2
Q
What is the benefit of not removing all parasites
A
Leaving a small number of parasites can be beneficial to the immune system of the host and reduce the likelihood of resistance
3
Q
What is hygiene hypothesis
A
Increasing societal frequency of diseases associated w/ hyperactivity of the immune system
4
Q
What are symptoms of heavy parasite loads
A
Poor performance, poor growth, weight loss, colic, diarrhea, dermatitis, and respiratory tract infection
5
Q
What is the most important GIT parasite
A
Small strongyles
6
Q
How can horses get tapeworms
A
Ingestion of a free living oribatid mite in the pasture that has ingested tapeworm eggs from an infected horse’s feces
7
Q
Where are adult tapeworms found
A
In the cecum hanging on to the lumen w/ suckers and hooks
8
Q
What can an abundance of tapeworms cause
A
An obstruction of the ileo-cecal junction, irritation to the epithelial lining, and mild colic
9
Q
How can you monitor for tapeworm presence
A
Fecal, spotting an egg in the feces, and blood test for antibodies
10
Q
How are tapeworms treated
A
With praziquantel specifically pyrantel
11
Q
What internal parasite is commonly found in foals
A
Roundworms/ascrids
12
Q
Why do ascrids last a long time in their environment
A
Because they have a tough membrane surrounding the egg
13
Q
How are ascrids transmitted
A
Oral ingestion of feces therefore they can be transmitted from foal to foal
14
Q
How are ascrid ova unique
A
They are ubiquitous to the area
15
Q
What does the life cycle of ascrids include
A
Larval migration in the body such as to the peritoneum, liver, lungs, and bronchi
16
Q
Why does deworming a foal typically cause colic
A
Because if the ascrids are killed they cant move w/ peristalsis
17
Q
What can you use to decrease the risk of colic after deworming
A
Mineral oil
18
Q
What is the immune self cure phenomenon
A
At 9-10 months of age the foal develops immunity to the parasite naturally removing them from the body
19
Q
What two parasites cant be determined between from their egg
A
Small and large strongyles
20
Q
How do horses get strongyles
A
They eat a blade of grass that has a 3rd stage larvae on it
21
Q
What type of strongyle can migrate past the gut
A
Large strongyles
22
Q
What do dormant small strongyles form
A
Cysts in the lining of the large intestine
23
Q
What is synchronous re emergence
A
When multiple small strongyle cysts burst at the same time causing hemorrhage
24
Q
What risk do strongyles bring to the horse
A
They tune into the endocrine system and infection can increase the risk of resistance
25
How do most horses infested w/ strongyles present
Asymptomatic but some can experience weight loss, reduced food intake, fever, anemia, diarrhea, and colic
26
How do horses get bot flies
They lay eggs on the horses hair shafts then the horse licks it of themselves or other horses
27
What is the life cycle of the bot fly
Hatch in the mouth and become larvae which develop in the stomach and are passed in the feces they the pupate and fly away
28
How are tapeworms managed
W/ a special treatment annually
29
How do you break the life cycle of internal parasites
Avoid overcrowding, low stocking density, removing manure, and deworming
30
What is the old method of internal parasite method
Rotation of different dewormers
31
What are the challenges of the old deworming method
Over deworming causing resistance
32
What are the benefits of deworming after determining the necessity w/ a fecal
As effective as treating all because 80% of horses dont have issues w/ parasites, cost efficient, reduces over use of dewormers, and reduces resistance
33
What are high shedders
Any horse less than 2 years old and horse at 500+ EPG
34
What are moderate shedders
200-500 EPG
35
What are low shedders
Under 200 EPG
36
When do we start deworming foals
At 2 months of age
37
What does killing every parasite do to a heavy shedder
Cause health issues such as colic
38
What is the prefered method for treating heavy shedders
A slow kill w/ 1/2 doses of dewormer over multiple days allowing the body to pass them efficiently
39
When are low shedders dewormed
In the fall (tapeworms) and spring
40
When do heavy shedders get dewormed
Fall, spring, and additional times throughout the year anywhere from every 6-12 weeks
41
How do you dose dewormer
Always at the higher end of the weight dose
42
What is avermectin products such as ivermectin and moxidectin used for
Adults for anything but roundworms
43
What dewormer are roundworms resistant too
Ivermectin
44
What dewormer can only be used to target encysted small strongyles
Moxidectin
45
What two types of dewormer are used for foals
Benzimidazole (fenbendazole and oxybendazole) and pyrimidine (pyrantel)
46
Why are benzimidazoles and pyrimidines only used in foals
Because there is a high amount of resistence seen w/ small strongyles
47
What type of horses is moxidectin bad for
Thin or small horses
48
What is the deworming protocol for foals
Begin treatment at 2 months of age, treat every 8 weeks until 1 year old, once over 9 months of age begin giving Moxidectin, and ivermectin at 12 months of age
49
What is the special deworming protocol for foaling mares
They get treated in the spring or w/ in 12 hrs of foaling w/ ivermectin
50
When are coggins tests done in the state of Missouri
Change of ownership, traveling, showing, breeding/boarding facility
51
What two diseases cant be protected against w/ vaccines
Equine Infectious Anemia (EIA) and Equine Protozoal Myeloencephalitis (EPM)
52
What is EIA
Immunodeficiency virus that is spread from blood to blood and causes fever, anemia, edema +/- weight loss
53
What is the treatment for EIA
There is no treatment typically horses are euthanized
54
How is spread of EIA reduced
By doing a coggins test
55
What is EPM
Neurologic disease that is spread by opossum feces that is ingested and causes progressive neurological symptoms such as muscle asymmetry
56
Can EPM be treated
Yes but can only be diagnosed w/ blood work and a spinal tap however most vets just treat if they feel thats what it is
57
What neurologic diseases can be treated w/ vaccines
Tetanus, Rabies, Eastern/Western Equine Encephalomyelitis (EEE/WEE), and West Nile Virus (WNV)
58
What is tetnus
A neurologic diseases caused by bacteria from the soil contaminating wounds that is known fo causing a prolapsed third eye lid and stiff tail/body
59
What is rabies
A neurologic disease that is spread by infected wildlife that causes +/- spasms, salivation, and sometimes aggression
60
What is the incubation period for tetanus
1-30 days and is often fatal but not contagious
61
What is the incubation period for rabies
2-8 weeks and is always fatal
62
What is EEE/WEE
Neurologic diseases that is spread by infected mosquitoes that get infected from a bird causing high fevers and neurologic symptoms
63
What is the incubation period for EEE/WEE
1-3 weeks, is often fatal, and is not contagious between horses
64
What is WNV
A neurologic disease that is caused by infected mosquitoes that get infected by birds causing neurologic symptoms and +/- fever
65
What is the incubation period of WNV
3-15 days, can be fatal, and is not contagious between horses
66
What is a core vaccine
Tetanus, rabies, EEE/WEE, and WNV are recommended vaccines for all horses regardless of their risk of exposure
67
What are common respiratory diseases that can be protected against w/ vaccines
Influenza, Equine Herpes Virus (EHV), and Strangles
68
What is the incubation period for the common respiratory diseases
7-14 days
69
What is the length of time horses are mildly ill w/ the flu and EHV
2-7 days
70
What diseases are highly contagious amongst horses
Flu, EHV, and Strangles
71
What is EHV Myeloenchephalopathy (EHM)
A neurologic strain of EHV that is fatal and not protected by vaccines
72
Which disease has one strain that can lead to late term abortions
EHV
73
What are risk based vaccines
Vaccines given based on the likelihood that the horse is exposed to an infected horse
74
What is pigeon fever
A bacteria infection that is spread by contact w/ the bacteria to a wound causing often external or internal abscesses
75
What type of environment does the pigeon fever bacteria thrive in
Dry drought like environements
76
Why can horses get pigeon fever multiple times
Because no immunity is build to the bacteria
77
What type of horses tend to be less susceptible to pigeon fever
Foals
78
What is Pars Pituitary Intermedia Dysfunction (PPID)
Cushings disease that is the result of something on or in the pituitary causing an increase in cortisol levels
79
What are symptoms of cushings
Lack of shedding, wooly coat, decrease in immune function (consistently sick), muscle atrophy, and +/- abnormal fat deposition on the crest of the neck
80
What does medication do for horses w/ cushings
Stops the excessive ACTH production but can not cure the disease or reverse the symptoms
81
What is Equine Metabolic Syndrome (EMS)
Insulin dysregulation that leads to abnormal chuncks of fat deposit all over the body including the crest of the neck, severe laminitis, difficulty losing weight, and insulin resistance
82
What is book in terms of a stallion
Reservation list of mares that are being bred to a particular stallion
83
What is service and cover in terms of a stallion
They are both another way to say breeding
84
When is breeding season for a stallion
Mid Feb to 1st of July
85
What is a teaser
A horses that is being used to determine behavior signs of estrus in mares
86
What is collection in terms of a stallion
Capture ejaculate from the stallion
87
What is belling out
Flaring of the glans penis that stretches the cervix and keeps the sperm from flowing out
88
What does the sheath produce and how often does it need cleaned
The sheath produces smegma and needs to be cleaned once a year
89
What is the function of the testis
Produce sperm and hormones
90
What is the location and orientation of the testis
Inguinal and horizontal in an oval shape
91
What is the size variation of the testis
Larger the testis the more sperm is produced so they are their largest during breeding season
92
What is average DSP
3-4 billion/day
93
When is puberty for horses male and female
Around 1 year w/ individual variation
94
What is the breeding season based on
Forage accessibility
95
What are the roles of testosterone
Development of secondary sex characteristics, sperm production, control of breeding behavior, and negative feedback control
96
What are secondary sex characteristics
Crusty neck, shiny coat, increased muscle mass, and large jowls
97
When are castrations done
6 months to 2 years
98
Why do we wait till at least 6 months
So they are easier to handle when sedating
99
How does testosterone affect growth
Allows for growth plates to close faster and build muscle faster
100
What is the preferred castration method
Field anesthesia so they can lay down either on their side or back for more visability
101
What does settled mean
The mare becomes pregnant
102
When is a mare typically bred for the first time
About 3 years old varying for different breeds or sizes
103
When is anestrus
Winter months
104
What is the function of the vestibular sphincter
Muscular sphincter that can tighten the vestibular area preventing urine from going towards the uterus
105
What is the function of the cervix
Muscluar sphincter that closes down tight to protect the uterus from infection and should only be open during heat
106
What is unique about the uterus
It is in a fixed location
107
What are the three barriers of defense
The vulva, vestibular sphincter, and cervix
108
What does a compromise to any barrier of defense mean
The mare is at high risk for consistent uterine infections and decreased pregnancy rates
109
What happens if the pelvic bone is lower than the uterus
The uterus will begin pulling the reproductive tract tilting the vulva resulting in a shelf and stretching the vulvar lips that the mare will defecate on and wind sucking will occur
110
What is the term used to describe the stretched out opening of the vulvar lips
Pneumovagina
111
What is the caslicks procedure
Done to manage a pneumovagina, tissue is trimmed from each side of the vulva then sown together closing the top of the vulva
112
What is a unique aspect of the cervix
It has longitudinal folds on the inside of the cervix that allows for sperm transportation and cervical expansion
113
What is a unique aspect of the uterus
Endometrial folds that helps w/ sperm transport
114
What are unique aspects of the ovaries
Cortex is on the inside, medulla is on the outside, mostly covered by mesothelium, ovulation can only occur at the ovulation fossa
115
What is the length of diestrus
14-15 days
116
What is the length of estrus
4-10 days
117
What is the timing for ovulation
24-48 hrs prior to end of estrus behavior
118
What is the concept of early cyclicity
To have foals born as close to Jan 1st as possible mares can be put under artificial lights so they are exposed to "day" light for a consecutive 16 hrs/day to trick their body it into cycling earlier
119
How long is the avg estrous cycle
21-22 days
120
When is foal heat
1-2 weeks post partum
121
What does estrogen control
Endometrial edema, relaxing cervix, estrogen increases as the follicle grows, and causes spike of LH for ovulation
122
What does progesterone control
Maintenance of pregnancy, closes cervix, tone of the uterus, and lack of edema
123
What does PGF2alpha control
Lycs the CL and decreases progesterone production
124
When is PGF2alpha released
When there is no recognition of pregnancy and uterine infections causing short cycling
125
What is the hormone present during the follicular phase (estrus
Estrogen
126
What occurs during the luteal phase (diestrus)
Release of progesterone keeping the uterus quiet for embryo development, increase in uterine tone, inhibits LH release, and FSH is still being produced allowing for selection to occur
127
How can we manipulate the estrous cycle
Inducing ovulation, short cycling, and synchronization
128
How is ovulation induced
W/ pharmaceutical agents such as hCG and deslorelin
129
What does hCG do
Acts like LH
130
What does deslorelin do
Acts like GnRH causing an LH surge and ovulation w/in 24-48 hrs
131
When can ovulation be induced
When there is a 35 mm follicle or greater and endometrial edema
132
What is short cycling
When PGF2alpha is given to shorten diestrus
133
When can you short cycle a horse
When there is a mature CL present
134
What is important to keep in mind when giving a horse PGF2alpha
Their lungs do not metabolize it as quickly so they get a much lower dose than similar sized species
135
What happens when synchronizing horses
Estrogen and progesterone is given for 10 days to shut down all gonadotropins then prostaglandin is given just in case a CL is present then 8 days after PGF2alpha is given ovulation is induced
136
When can synchronization occur
At any point in the cycle
137
When do we strive to breed
12-48 hrs before ovulation
138
Why do we want to breed 12-48 hrs prior to ovulation
Because sperm has to go thru some final maturation steps prior to being fertilized
139
What are the two choices for monitoring ovulation when breeding natural cover and onsite AI
Breed every other day or ultrasound to determine when to breed then induce ovulation
140
When are uterine cysts a problem
When there is a large cluster of them keeping an embryo from traveling in a horn preventing MR
141
What occurs on days 5-6 of gestation
Embryo moves into the uterus
142
What occurs during days 7-15 of gestation
Transuterine movement for MR
143
What occurs on days 16-17 of gestation
Fixation which is where it physically cant move in the uterus anymore
144
What occurs at day 30 of gestation
Development of embryonic chorionic girdle
145
What occurs at day 35 of gestation
Embryo forms endometrial cups
146
What is the embryonic vesicle
A fluid filled membrane that surrounds the embryo
147
What occurs during the first trimester
Setting up for maintenance of pregnancy, when EED occurs, fixation, development of embryo chorionic girdle, development of endometrial cups, and eCG supports pregnancy thru this trimester
148
What occurs during the second trimester
The smooth sailing trimester, least amount of fetal growth, and least amount of stress on the mare's body
149
What occurs during the third trimester
Largest amount of fetal growth, most stress on a mares body, and when the mare needs additional nutrients
150
Why are endometrial cups so important
They produce eCG which causes maintenance of the primary CL and causes formation of secondary CL
151
How are secondary CLs formed
Ovulation continues to occur lutenizing follicles increasing progesterone production
151
How long is pregnancy maintained by endometrial cups
From days 35 to 120 of gestation
152
What does the fetoplacental unit produce
5 alpha pregnanes
153
What does the fetoplacental unit require to maintain pregnancy
A healthy fetus and placenta
154
What type of placenta does the horse have
Epitheliochorial
155
What is the downfall of the epitheliochorial placenta
Large molecules can not pass thru so antibodies cant be transferred to the fetus from the mother and there are only two antibiotics that can affect the placenta
156
What are the three ways to detect pregnancy
Transrectal ultrasound, rectal palpation, or monitoring any return in estrus behavior
157
What typically happens w/ twin pregnancies
One twin often dies early during MR
