Unit 4 And 5 Flashcards
In animals, if not pregnant,the endometrium is
Reabsorbed by uterus
During estrus, body temp
Increase
Phases of estrus cycle
Pemda
Proestrus
Estrus
Metestrus
Diestrus
Anestrus
Proestrus duration
1 day to 3 weeks
-One or several follicles of the ovary starts to
grow (depending on species)
Endometrial (lining starts to grow under
estrogen influence
What stage of estrus
Pro estrus
Follicles are maturing and estrogen exert its biggest influence
Estrus
Dominat follicle reaches its maximum,
growth, matures, & ovulates
Estrus
Estrus stage wherein estrogen influence subsides and cl starts to form
Metestrus
In metestrus, uterine lining begins to secrete small amounts of
progesterone
During this phase, Cl produces progesterone
Diestrus
If the animal is not pregnant in diestrus, it terminates w/ the regression of
Cl
It is the most consistent period in the cycle
Diestrus
In anestrus, melatonin regulates – release by hypothalamus
Gnrh
Anestus is controllers
Light exposure
Mammals that only cycle once a year and exhibit a long anestrus regardless of pregnancy status
Monoestrus
Mammals that cycle repeatedly in a year until interrupted by pregnancy
Polyestrus
Diestrus animal
Dog
Polyesters animals
Cat, cow, sows
Seasonally polyestrus animals ) short day breeders
Sheep and goat
Long day breeders
Horses
Estrus in cow lasts
6-30 hrs
Conclusive sign that cow is in heat
Standing heat
Metestrus in cow lasts
3-5 days
Cows is capable of what type of bleeding during metestrus
Metestral bleeding where capillaries may break and result in small blood loss
Ovulation in cow
About 10-15 hours after end of estrus
It is the period of cl formation
Metestrus
Diestrus in cow lasts
12 days
In early part of cow diestrus, there is
Increased progesterone production
In diestrus,__ lyses the cl and initiates a return to estrus
PGF2A
No of follicular waves generated
Ewe and Cow:
mare:
Sow:
Doe:
Ewe and Cow: 2-3 waves
mare: 1-2 waves
Sow: 1 wave
Doe: 4 or 5 waves
Breeding season of horses
Summer
Anestrus season of horses
Late fall and winter
Estrus length in mares
5-7 days
Becomes shorter at the peak of cycling season
Ovulation in mare
1-2 days before end of estrus
Ovulation in mares
1-2 days before end of estrus
Ovulation in mares
1-2 days before end of estrus
In diestrus in mare’ it is dominated by what hormone
Progesterone
Pins her ears back
Squeals, kicks, and strikes if the stallion approaches
What estrus phase is mare into?
Diestrus
In mare, FsH peaks during
Diestrus
Lh has a long half-life due to
Sialic acid residues
There is no metestrus or proestrus in what animal?
Mare
Ewe breed in –
Short day lengths
Ewe cycle or come into heat every
17 days
— inhibits the secretion of the Gnrh from the hypothalamus and lh and Fsh from ant. Pit. Gland
Melatonin
It decreases motor activity, induces fatigue and lowers body temperature
Melatonin
Lactational anestrus occur until after
Weaning
Sow is insemenated — after onset of standing heat
12-26 his
Behavioral estrus last – in sows
2-3 days
Owlation occurs when in sow
After near the end of behavioral estrus
Animal that displays homosexual tendencies
Cow
In cow when has higher frequency of mounting?
At night
Elevates her tail
Squats to urinate (breaking down)
Everts the clitoris (winking)
- Accepts the stallion for breeding
Guess what animal
Mare
Displays no signs of estrus if the male animal is not
present
Ewe
Flagging tail
Localization/ bleating
What animal in estrus?
Doe
Places her front quarters on the ground,
elevates her hind quarters and lifts her tail to
one side
When the dorsal caudal area is stroked, she will
tread with her hind legs
Dragster posture
Feline estrous cycle
Peida
Proestrus
Estrus
Interestrus
Diestrus
Anestus
Pro estrus in cats last
1-2 days
Estrus in cats length
3-16 days
Period between successive estrus in cats if no ovulation
Interestrus
If there is no ovulation in cats, cl formed and secretes
Progesterone
Hallmark of diestrus in cats
Elevated progesterone
Pseudopregnancy in cats lasts
35 to 40 days
Canine estrus cycle
Pema
Pro
Estrus
Met
An
Cells present in pro estrus
Large intermediate and superficial cells
Vulvar edema and swelling is observed in dog in what stage of estrus?
Pro estrus
During estrus there is presence of what cells?
90% superficial cells and bacteria is present
During diestsrus the uterine glands in dogs will undergo
Hyperplasia and hypertrophy
Cells present in anestrus in dogs
Parabasal and intermediate cells
The dog’s heat is interrupted and then
continued at a later time
Split heat
The bitch exhibits signs of pro-estrus with the
typical bleeding but once estrus approaches, signs of heat disappear for some time
Split heat
No external manifestations exist suggesting
that heat has occurred
Silent heat
The presence of a bitch in heat may stimulate the
heat cycle in other bitches
lost
Induced estrus
Youngest cells of vaginal epithelium
Basal cells
Smallest among the vaginal epithelium cells
Parabasalcells
Cells that has high n/c ratio, round nucleus, and basophilic cytoplasm
Para basal cells
Oldest vaginal cells having small pyknotic nuclei
Cytoplasm is abundant, blue-green, and keratinized
Superficial cells
- Vary in size but are usually two times the size of parabasal cells N/C ratio is decreased
Have large amounts of blue-green, keratinized cytoplasm
Borders round to irregular & folded
Intermediate cells
Vaginal cytology stains
Romanowsky
stains
(Wright,
Giemsa,
Eishman, Diff-Quik)
New methylene blue
Toluidine blue
Papanicolaou stain
Hematoxyline and eosin (H&E)
The process of the gradual transformation of germ cells into spermatozoa
Spermatogenesis
Site of spermatogenesis
Seminiferous tubules
A cell that will be develop into sperm
Germ cell
It nurtures the germ cell throughout the development process
Somatic or sertoli cells
Spermatogenic cells that rest on the basement membrane
Spermatogonia
Located in the middle of the seminiferous tubules
Spermatocytes
Located in the adluminal region
Spermatids
Phases of spermatogenesis
Pmd
Proliferative phase
Meiotic phase
Differentiation phase
Phase that takes place in the basal compartment of the seminiferous tubules
Proliferative phase or spermatocytogenesis
Spermatogonia undergo several mitotic divisions with the last division resulting in primary spermatocytes
Proliferative phase
Spermatocytogenesis
Types of spermatogonia found in the basal compartment
Spermatogonia A
Spermatogonia intermediate
Spermatogonia B
Meiotic phase takes place in
Adluminal compartment of the seminiferous tubules
Reduction of the number of chromosomes
in the gamete in half (from diploid to the
haploid state)
Meiotic phase
Longest lifespan of all sperm cell
Spermatocytes
Short lived cells
Secondary spermatocytes
Differentiation or spermiogenesis takes place in the
Adluminal compartment
During differentiation, - – are formed
Acrosome and flagellum is formed and cells become potentially motile.
It is non-motile, round, non - specialized
Spermatid
It is motile, elongate, specialized components, special surface molecules.
Spermatozoa
Phases of spermiogenesis
Gcam
Golgi.
Cap
Acrosomal
Maturation
Phase wherein acrosomic vesicle spreads over the nucleus of the round spermatid and flagellum starts to form
Cap
Acrosomic vessicle formation
Golgi phase
The spermatid nucleus and cytoplasm elongates, acrosome covers the majority of the anterior nucleus
Acrosomal phase
Mitochondria is assembled around the flagellum and the flagellum is completely formed
Maturation
Sperm head contains
Nucleus, acrosome, post nuclear cap, plasma membrane cell
Part of the head of sperm that is located below acrosome and lateral to nucleus
Post nuclear cap
It is a bag of enzymes used to help sperm enter egg
Acrosome
It is the attachment of the head to the tail
Capitulum
It provides energy to move axial filaments
Mitochondria
•largest part of the tail and provide motility to the
sperm
of middle piece
Principal piece
It is a progression through a complete series
of cellular associations (stages) at one location
along the seminiferous tubule.
Seminiferous Epithelium Cycle
Seminiferous Epithelium Cycle duration
Bull -13.5
Ram - 10.4
Stallion- 12.2
Boar - 8.3
Bull -
Ram -
Stallion-
Boar -
Spermatogenesis IS controlled by a complex feedback mechanism involving the’
Hypothalamus’ anterior pg and testes
Testosterone and estradiol feedback upon the
hypothalamus causing a slow down in the release
of GnRH, which results in a
Reduced output of Fsh and Lh
Glands and their respective hormones
-Hypothalamic hormone:
-Anterior pituitary:
-Testes:)
Hypothalamic hormone: GnRH
-Anterior pituitary: LH and FSH
-Testes: testosterone (Leydig cells) and estradiol &
inhibin (Sertoli cells)
Hormone that acts on Leydig cells
Lh
A hormone that stimulates the production of testosterone
Lh
Hormone that Acts on the Sertoli cells
Fsh
Stimulate spermatogenesis and Sertoli cell function-
Fsh
In the Sertoli cells…… is responsible for activation of
aromatase enzyme for conversion of testosterone into estradiol
Fsh
Produced by sertoli cells
negatively feeds back on
the
anterior
pituitary to selectively suppress FSH
Inhibin
In the Sertoli cells: bound by androgen binding
protein and taken into the lumen of the seminiferous tubule, for transport to the epididymis
What hormone?
Testosterone