Term
| 2. Learn the 4 different stages of the estrous cycle including the length of time for each. (Characteristics – table) |
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Definition
Proestrus - ~ 9d
Estrus - ~ 9d
Diestrus - ~60d
Anestrus – depends on whether preg or not. 79 to 80 days for CL to regress and 130 days to repair endometrium |
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Term
| What is the gestation period for dogs? For cats? |
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Definition
Dogs 62 days from ovulation
Cats – 58 -65 days |
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Term
| Do small breed dogs reach puberty earlier or later than large breed dogs? |
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Definition
| Earlier, as early as 5 mo |
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Term
| At what age may fetuses be palpated in the dog and cat? |
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Definition
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Term
During the
canine reproductive cycle, estrogen peaks followed by the luteinizing hormone (LH) peak
1-3 days later. Ovulation occurs 1-3 days after the LH peak. The dog is in estrus or
‘heat’ starting at the LH peak or several days before or after, estrus lasts for 5-9 days,
breeding may occur on multiple days, and the male’s sperm is fertile for 4-6 days. All of
these factors result in an uncertain conception date, and thus variable gestation length
(56-72 days) when counting after the breeding date. Canine gestation length is fairly
consistent (65 ± 1 days) when counting after the LH surge. Assessment of gestational
age ultrasonographically is thus defined in relation to days after the LH peak. In the cat,
conception takes place shortly after breeding, and their gestational age is 61 ±1 days. |
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Definition
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Term
| At what age may fetuses be palpated in the dog and cat? |
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Definition
At approximately 28 days post LH peak in the dog (range 21 to
35 days) and 30 days post breeding in the cat, the individual gestational sacs can be
palpated. As the uterus gets larger, the individual sacs can no longer be differentiated.
The large uterus can often still be palpated, but pathologic conditions of the uterus
cannot be distinguished from pregnancy |
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Term
| At what age can fetal mineralization be detected radiographically? |
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Definition
Litter size can be most accurately predicted radiographically (93%
accurate). At approximately 45 days post LH peak in the dog and 36-45 days post
breeding in the cat, fetal mineralization can be seen radiographically. Possible reasons
for missing a diagnosis of pregnancy radiographically include masking by overlying
viscera with ingesta, underexposure and scant fetal mineralization. |
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Term
| At what age can u/s be used to detect fetuses? |
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Definition
Ultrasound is a very sensitive and specific imaging method to diagnose pregnancy if it is
performed at least 30 days after breeding in the dog and at least 16 days after breeding
in the cat. Pregnancy has been diagnosed as early as 10 days after breeding in the dog
and 11 days after breeding in the cat. False negative exams can occur due to
overlooking a fetus, which could happen due to gas or fecal material creating shadows.
False positives could occur due to viewing a loop of small intestine, but most of the time
imaging in a second plane reveals that intestine becomes tubular, whereas a gestational
sac does not. Visualization of a gestational sac is considered to confirm pregnancy. |
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Term
| What tissues are removed during an OVH? |
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Definition
| Ovaries, oviducts, and uterus |
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Term
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Definition
Dogs, and more rarely cats, can exhibit signs of a pseudo, or false pregnancy 6 -12
weeks post estrus. This state can be clinically unapparent, or signs seen can include
weight gain, mammary gland hyperplasia and lactation, mucoid vaginal discharge,
inappetance, restlessness, nesting and mothering of inanimate objects. The importance
of this condition is to know that all animals exhibiting the above symptoms or behaviors
are not necessarily pregnant. |
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Term
| What two main types of hormones are produced in the ovary? Where is each produced? |
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Definition
estrogens and progestins
estrogens are produced by the cells of the developing ovarian follicles and are responsible for the physical and behavioral changes that prepare the animal for breeding and pregnancy
Progestins, principally progesterone, are produced by the corpus luteum that develops from the empty follicle after ovulation. Progestins help prepare the uterus for implantation of a fertilized ovum. They are also necessary for pregnancy to be maintained once implantation occurs |
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Term
| What changes does an ovarian follicle undergo as it changes from a primordial follicle to a mature follicle? |
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Definition
primordial follicle consists of:
- immature reproductive cell (the oocyte) surrounded by single layer of flattened follicular cells. When FSH is released from the anterior pituitary the whole ovary is based in it something however causes just a few of the thousands of primordial follicles to begin developing. This is known as follicular recruitment or follicular activation.
–- once activated it is referred to as growing follicle
-follicular cells become thickened into cuboidal shapes and begin to multiply
- multiple layers of follicular cells form around the developing oocyte
- at this stage the follicular cells are called granulosa cells
- as the granulosa cells multiply the follicle starts rapidly in size
- the granulosa cells do more than just physically surround the developing oocyte, they also produce estrogen hormones
- for larger the follicle becomes the greater the amount of estrogen hormones produced
- fluid filled spaces begin to form between granular cells
- gradually become confluent forming one large fluid filled space called the Antrum
- - follicle max size, large, called mature follicle (graafian follicle/vesicular ovarian follicle)
_ inside, oocyte on mound of granulosa cells called the cumulus oophorus, surrounded by thin layer of granulosa cells called the corona radiata.
- most of volume of mat fol is fluid-filled antrum
- estrogen produ. at max level
- ovulation (rupture of mature follicle w/ release of repro cell into oviduct) occurs spontaneously as a result of the rising level of LH
- once this occurs, the mat repro cell is called an ovum
- rupture releases the fluid from the antrum, carrying the ovum and corona radiata with it\- empty follicle fills w/ blood that rapidly clots, forming the corpus hemorrhagicum
- cont stim by high LH level, granulosa cells that line the blood-filled follicle begin to multiply again
- form solid structure, corpus luteum ("yellow body"), as large as mat foll just before ovul.
- CL produces progestins (principally progesterone
- if ovum fertilized and implants, sends endocrine signal to the ovary that causes the CL to be maintained, if not, no signal sent and the CL degenerates |
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Term
| After ovulation has occurred, what cells in the ovary multiply to form the CL? |
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Definition
| the granulosa cells that line the blood-filled follicle |
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Term
| In addition to dystocia, what other common pregnancy disorders may occur? |
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Definition
| eclampsia (puerperal tetany), abortion, mastitis, pyometra, retained fetus or placenta |
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Term
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Definition
an infxn of the uterus in dogs and cats causing a variety of clinical and pathological signs related to genital and systemic dz.
it is generally recognized that progesterone and estrogen and their receptors have a role in the development of pyometra; however,
the infxn is triggered by bacterial involvement |
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Term
| What is another term for eclampsia? |
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Definition
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Term
| What are the clinical signs of pseudopregnancy and when do they occur? |
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Definition
- usually begin four to nine weeks after the previous heat period, and mimic the symptoms of true pregnancy.
- The more common signs of pseudo-pregnancy include mammary gland enlargement with or without the production of milk, lethargy, periodic vomiting, and fluid retention.
- The female often has a decreased appetite but seldom appears to lose weight, probably due to the amount of excess fluid she retains.
- These symptoms can occur at any age and do not necessarily follow every estrus. The severity of the clinical signs varies between individuals and may vary from one cycle to the next in the same dog.
- Behavioral changes of pseudo-pregnancy include nesting, mothering activity, restlessness, decreased interest in physical activity and occasionally even aggression.
- Some affected dogs will show signs of a false labor and then protectively guard toys or other small objects. |
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Term
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Definition
the inability to expel neonates through the birth canal from the uterus
- results from abnormalities assoc w/ birth
- due to either primary or secondary uterine inertia
- primary – failure of uterine contractions sufficient to deliver
- secondary – fetal obstruction due to lg pups, narrow birth canal, abnormal position, etc |
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