Week 1 Flashcards
1
Q
How are the bladder & rectum formed
A
growth of urorectal septum divides cloaca into bladder & rectum
2
Q
What is the mesoderm and what are its divisions
A
Everything that is not skin or lining of gut
divisions:
- paraxial mesoderm
- intermediate mesoderm
- lateral plate mesoderm
3
Q
How do nephros develop
A
intermediate mesoderm develops 3 bilaterally symmetrical sections from cranial to caudal, connected to coelomic cavity:
1. Pronephros
2. Mesonephros
3. Metanephros
4
Q
Label the nephros diagram
A
5
Q
Describe fish kidney development
A
Pronephros replaced by mesonephros
Fusion of mesonephros
- fish: fuse to make single kidney
- amphibians: caudal poles fuse to create V or Y shape
Mesonephros has reproductive, endocrine & excretory elements
No metanephros
6
Q
describe kidney development in reptiles, birds & mammals
A
7
Q
Compare mesonephros to metanephros
A
8
Q
Where do gonads form from
A
From regressing mesonephros
9
Q
How are kidneys formed
A
10
Q
Label the diagram
A
11
Q
Label the diagram
A
12
Q
What are the red lines
A
2 layers of peritoneal cells
Space between layers called vaginal cavity (continuous with peritoneum)
Peritoneal fluid between layers
13
Q
Label the structures
A
14
Q
What is the tunica albuginea made of
A
connective tissue, smooth muscle
15
Q
What is the visceral vaginal tunic made of
A
peritoneum, visceral layer
16
Q
Label the diagram of testis histology
A
17
Q
Label the testis histology
A
18
Q
Describe sperm cell development
A
Early cells sit at basement membrane (spermatogonia)
Spermatogonia divide by mitosis and form primary spermatocyte
Then undergo meiosis to form haploid cells and differentiate and elongate into sperm
Sperm sits in Sertoli cells on basement membrane which stretch into lumen of tubule
Sertoli cells help formation of sperm (nurse germ cells)
Germ cells squeeze between sertoli cells & go closer and closer to lumen as they develop
19
Q
What can you see on this testes ultrasound
A
20
Q
Label the image
A
21
Q
What is the function on the epididymis
A
Transport spermatozoa
resorption of fluids
secretion of proteins
22
Q
What is epididymal transit time
A
Time taken for spermatozoa to travel from proximal head to distal tail of epididymis
23
Q
What is the ductus deferens
A
Connects epididymis (tail) to pelvic urethra
very strong smooth muscle wall for propulsion of spermatozoa
24
Q
Label the diagram
A
25
Label the diagram of the spermatic cord
26
Label the diagram of spermatic cord
27
What are the functions of the pampiniform plexus
Venules wrap around arteries so heat is transmitted into venous blood to cool testes
By the time artery arrives at testes its cooler
Testosterone passes into venous blood and then back into artery to travel to testes
28
What muscles play a role in testes temperature control
29
Label the blood supply to the testes
30
What are the male accessory reproductive glands and what do they produce
31
Label the diagram
32
What is the colliculus seminalis
Opening of ejaculatory ducts
common duct of ampulla & vesicular gland
33
Fill in the accessory gland table
34
Where are the urethralis m. & bulbospongiosus m. & what is their function
Urethralis muscle: surrounds pelvic urethra
Bulbospongiosis muscle: surrounds bulbourethral glands & penile urethra
Both striated muscles important for transport of semen through urethra
35
Label the 3 parts of the penis
36
What are these and what are their functions
37
Describe the dog penis erectile tissue
38
What are the 2 types of penis
Fibroelastic:
- ruminants, pigs
- fibroelastic tissue in corpus cavernosum
little increase in length & girth during erection
Musculocavernous:
- stallion, dog
More muscular, less connective tissue in CC
significant increase in length & girth during erection
39
Label the glans penis
40
label the structures
41
Label the pelvic diaphragm diagram
42
What are perineal hernias
Occur when muscles of pelvic diaphragm fail to support rectal wall
Most often occuring in male intact dogs
43
Identify A, Ai, B and the structures pointed at
44
Identify the structures
45
What blood vessels supply the female genital organs
Ovarian artery
Uterine artery
Vaginal artery
Internal pudendal artery
46
In the male, urethra, accessory glands & penis are all supplied by which artery
Branch of internal pudendal artery
Divides into deep & dorsal penile arteries at level of ischiadic arch
47
Which artery does the testicular artery branch from
Abdominal aorta
48
Label the diagram
49
Label the diagram
50
When does testes descent occur across species
51
Describe testicular descent
1. testes lie in retroperitoneal position & are attached caudally to ligamentous gubernaculum
2. As fetus grows, testes pushed against peritoneum causing peritoneal cells to wrap around gubernaculum (allows vaginal process to form)
3. Gubernaculum passes through inguinal ring (transabdominal phase)
4. Then undergoes rapid period of expansion, pulling testes down towards base of scrotum (inguinal-scrotal phase)
52
What is puberty and what are the requirements
53
Describe LH in male hypothalamus
Small LH surges every 2-6 hours followed by testosterone
54
Describe LH in female hypothalamus
High amplitude preovulatory episodes once every 20 days
Basal low amplitude pulsatile episodes between surges
Females have surge centre
55
What limits puberty onset in females
Pre-puberty GnRH pulses are low
56
What triggers puberty onset in females
Increased oestradiol levels stop inhibition at tonic centre
Surge centre stimulated which leads to ovulation & puberty
57
Why is amount of fat & body maturation important in female puberty
58
Describe role of Kisspeptin neurones in puberty onset
59
What are some external & social factors that affect female puberty
60
What are some strategies used to advance or delay puberty
61
Fill in the table with ages of puberty
62
What does meiosis produce
Haploid cells
63
What are the phases of mitosis
64
In which meiotic division does DNA replication occur
1st meiotic division
65
Briefly state what happens in meiosis
66
What happens in prophase 1
nucleolus shrinks
centrioles migrate to opposite poles
spindle forms (green)
nucleus & chromatin stained blue
chromosomes condense
- homologous chromosomes undergo synapsis & lie together to form bivalent structure
- homologous chromosomes interlink
- chiasmata form
67
What are the 5 stages of prophase 1
67
What are these
chiasmata
68
What happens in metaphase 1
nuclear envelope disappears
homologous chromosomes move to equator of spindle
Centromeres of each bivalent chromosome orientate to opposite poles
68
What happens in anaphase 1
homologous chromosomes separate & migrate to opposite poles of spindle
one chromosome with 2 chromatids arrives at each pole
69
What happens in telophase 1
cytoplasmic division starts
spindle breaks down
nuclear envelope & nucleoli form
70
What happens in the 2nd meiotic division
71
Fill in the blanks
72
Describe spermatogenesis
73
Fill in the blanks
74
Describe oogenesis
75
What are alleles
alternative version of same gene (same function but with small difference in gene sequence)
76
What are sources of genetic variation
77
What is independent assortment of chromosomes
78
What is X chromosome inactivation
females have mosaic of 2 types of cells: half from active X of father & half from active X of mother
79
what are somatic vs germ line mutations
80
What is non-disjunction
81
What is aneuploidy
82
What are the 2 types of nondisjunction
83
What is a monosomic zygote
Only has 1 copy of particular chromosome
84
What is a trisomic zygote
Has 3 copies of particular chromosome
85
what type of changes can a breakage of chromosome lead to
86
What is happening in each
87
What is Klinefelter syndrome
result of an extra chromosome in male producing XXY individuals
XXY tortoise-shell cats are infertile
88
What is monosomy X
Also known as Turner syndrome
Produces X0 females who are sterile
89
What does the mesonephros do before urinary development
Temporary embryonic kidney
90
Describe male gonad early development
1. Pair of gonadal ridges form on posterior abdominal wall adjacent to mesonephros
2. Primordial germ cells from yolk sac endoderm migrate to ridges
3. SRY gene on Y chromosome influences germ cells to differentiate into testicular primordia
91
Describe female gonad early development
1. Pair of gonadal ridges form on posterior abdominal wall adjacent to mesonephros
2. Primordial germ cells from yolk sac endoderm migrate to ridges
Extra pair of duct forms from grooves, lateral to the nephros
3. Grooves sink into mesoderm of abd wall to become paramesonephric ducts (they also start to form in males but regress)
4. PMN ducts elongate cranially & caudally
5. Ducts fuse or not depending on species and form L & R uterine horns
6. They remain open at cranial ends to form ampullae of oviducts
7. caudal ends form bud from endoderm of cloaca which forms vagina & cervix
8. Ovaries migrate caudally to post renal position
9. Fused region of PMN ducts becomes body of uterus
92
What do mesonephric tubules form in males
efferent ducts
93
What does the mesonephric duct form in males
epididymis & ductus deferens
94
What happens to mesonephric ducts in females
regress in females but can leave cystic remnants
95
What happens to paramesonephric ducts in males & females
Degenerate in male but persist in females
96
What us the trigone of the bladder
97
Describe testicular development
1. undifferentiated sex cords align themselves against rete tubules
2. rete tubules & mesonephric ducts interconnect to provide continuity with sex cords that will become seminiferous tubules
3. epithelial cords become seminiferous tubules & mesonephric duct is gradually transformed into epididymis & ductus deferens
98
What are rete tubules
Network of tiny ducts that ultimately connect seminiferous tubules to efferent ducts
99
Describe ovarian development
1. paramesonephric & mesonephric ducts still intact
2. paramesonephric duct continues to develop
3. primitive follicles appear at periphery of ovary & mesonephric ducts & tubules regress while paramesonephric ducts develop
4. distinct clusters of follicles seen. sex cords gone.
100
Where is the adrenal cortex derived from
some of the regressing mesonephric tubules
101
where is the adrenal medulla derived from
neural crest cells which migrate into centre of adrenal cortex
102
What is an ectopic ureter
1 or both ureters enter urethra/vagina downstream of bladder sphincter
103
What is freemartinism
104
What are the signs of a freemartin calf
105
What is the order in which sperm travels through male genital tract
1. seminiferous tubules
2. straight tubules
3. rete testis
4. efferent ductules
5. epididymis head
6. epididymis body
7. epididymis tail
8. deferent duct
9. ejaculatory duct
10. urethra
106
What is the origin of testicular arteries
aorta
107
Why do males have a vaginal cavity
It contains peritoneal fluid to lubricate testes for movement
108
What is the function of the gubernaculum
Guide testes in their decent from initial abdominal position down into inguinal canal
109
What are the 4 muscles of the male reproductive tract and what is their function
110
Label the diagram
111
Label the diagram
112
Label the sperm diagram
113
Label the male gonad
114
Label the diagram
115
Label the diagram
116
Label the diagram
117
Where is GnRH produced
hypothalamus
118
Where are FSH, LH, Prolactin & oxytocin produced
Pituitary
FSH, LH & prolactin anterior
oxytocin posterior
119
What hormones does the ovary produce
Oestrogens, progesterone, inhibin, oxytocin, relaxin & some testosterone
120
What hormones do the testes produce
Testosterone & other androgens, inhibin, oestrogen
121
What hormones do the uterus & placenta produce
Prostaglandin F2a, progesterone, oestrogen, eCG & hCG
122
Fill in the HPG axis
123
Describe the hypothalamo-hypophyseal-portal system
124
Describe the male HPT axis
1. male hypothalamus releases frequent intermittent bursts of GnRH
2. causes pulse of FSH & LH
3. pulse of LH causes pulse of testosterone
4. sertoli cells release inhibin which inhibits FSH
125
Fill in the male HPT axis
126
What happens in a follicle
Oocyte develops
Oestradiol secretion: receptivity & conception
127
What does the corpus luteum release
Progesterone for pregnancy support
128
In what groups of hypothalamic neurons is GnRH produced in females
Surge centre & tonic centre
129
What is the difference between GnRH secretion in surge vs tonic centre
130
What happens during the follicular phase
1. FSH stimulates follicle to grow & produce oestradiol
2. for most of follicular phase E2 is low which has negative feedback role
3. approaching ovulation there is critical switch & rising E2 become positive leading to LH surge & ovulation
4. inhibin inhibits FSH
131
What happens during the luteal phase
Luteal P4 exerts negative feedback on GnRH neurons so there is no more oestrus
Stimulates lining of uterus to be secretory & support early pregnancy
Stimulates mammary gland
132
What happens during luteolysis
CL undergoes structural & function regression
P4 decreases which removes negative feedback
133
What is spermatogenesis
134
What are the 3 phases of spermatogenesis
1. proliferation
- mitotic divisions of spermatogonia. large number of B spermatogonia produced
2. meiosis
- crossing over for genetic heterogeneity. haploid spermatids produced
3. differentiation
- formation of cell capable of fertilisation
135
What happens in spermatogenesis
1. A-spermatogonia undergo mitotic divisions from A1 to A4
2. I-spermatogonia undergo mitotic divisions to form B spermatogonia
3. B-spermatogonia undergo mitotic division to primary spermatocytes
4.primary spermatocytes double their DNA in preparation of first meiotic division
5. secondary spermatocytes undergo meiosis 2 to produce haploid spermatids
6. spermatids differentiate into mature sperm cells with tails sticking into lumen
136
How is synchrony assured in spermatogenesis
intercellular bridges between groups of cells so they divide in groups
137
are you more likely to see a primary or secondary spermatocyte
Primary because secondary spermatocytes are short lived
138
What are the phases of spermatogenesis differentiation
1. golgi phase
2. cap phase
3. acrosomal phase
4. maturation phase
139
Describe the stages of spermatid differentiation
1. golgi phase
- vesicles of Golgi fuse to form acrosomic vesicle
- centrioles move to base of nucleus
2. cap phase
- acrosome forms cap over spermatid nucleus
- golgi apparatus migrates & dissapears
- primitive flagellum forms
3. acrosomal phase
- acrosome spreads & nucleus elongates
- manchette tubules formed
Neck & annulus formed
4. maturation phase
- manchette forms postnuclear cap
- mitochondria form middle piece
140
What are the features of spermatozoa
141
What is the cycle of seminiferous epithelium
Progression through complete series of stages at 1 location along a seminiferous tubule
Cycle duration varies across species
Sperm is only released into lumen at cross-section 8
142
Define stage, stage duration, cycle & cycle duration regarding spermatogenesis
143
What is spermatogenesis dependent on
Production of:
- GnRH secretion from hypothalamus
- FSH & LH from anterior pituitary
- Testosterone & oestrogen from gonad
144
What are the roles of LH & FSH in spermatogenesis
LH:
- binds to receptors on Leydig cells
Leydig cells produce testosterone
FSH:
- bind to receptors on Sertoli cells to enable function
* converting testosterone to oestradiol
* produce inhibin
145
What is sex determination
Developmental decision that directs bipotential gonad to develop as a testis or ovary
146
What is the difference between genotype & phenotype
Genotype is genetic makeup of an individual
Phenotype refers to observable physical traits
147
Where do germ cells migrate from
Yolk sac (endodermal layer)
148
What are the 3 levels of sexual dimorphism
149
Describe the sexual differentiation of the brain
150
Describe how XY germ cells become sperm
1. XY germ cells undergo mitosis during migration
2. growth arrested when they reach gonad & remain in testis in G0 phase until after birth
- induced by meiosis inhibitory factor secreted by Sertoli or myoid cells
3. resume cell cycle after birth & form haploid spermatozoa
4. Sertoli cells nurture germ cells
5. spermatogenesis complete at puberty under influence of FSH & LH
151
Describe how XX germ cells become oocytes
1. XX germ cells undergo mitosis as they migrate to genital ridge & enter oocyte
2. undergo initial stages of 1st meiotic division & become arrested at prophase 1 by birth
3. become surrounded by single layer of granulosa cells to form primordial follicles
4. follicle development continues but oocytes remain arrested until they are stimulated by FSH & LH at puberty
152
Describe the function of testosterone, LH, FSH, GnRH & inhibin in males
Testosterone: development & maturation of sperm cells
LH: stimulate testosterone production
FSH: promote development of sperm cells
GnRH: stimulate release of LH & FSH
Inhibin: inhibit release of FSH from pituitary gland to regulate spermatogenesis
153
what is stallion-like behaviour
Mate guarding, vocalisation, courtship displays (e.g. prancing), challenging other males
154
What is flehmen
Curl back upper lip & expose front teeth to inhale scents associated with reproductive & social information
Allows animal to use vomeronasal organ in roof of mouth to detect pheromones
155
What is the difference between stallion-like behaviour & aggression
Not all stallion-like behaviours are aggressive & actions are a reproductive response whereas aggression is more general
156
When are stallions normally gelded
between 6 months & 2 years of age
157
What behaviour would be expected of a castrated male in presence of female in oestrus?
Less focused on mating behaviours & calmer/more manageable as they no longer experience hormonal fluctuations associated with testosterone
158
Fill in the testicular morphology table
159
Label the sperm
160
Label the diagram
161
What is the role of seminal plasma in female tract
Not required for fertilisation
Helps sperm survive in female tract
Transport medium
Nutritional support
Buffering capacity (cervix acidic)
162
Where is semen deposited in cattle
163
Where is semen deposited in pig
164
Fill in the semen deposition table
165
Describe the journey of sperm through female tract
166
What happens to semen at copulation
Semen coagulation to prevent further mating (domestic animals) or vaginal plug (rodents)
Loss of spermatozoa because presence of sperm induces immune reaction (foreign body)
167
How does sperm move
straight line
head rotates left & right
flagella movement
Transport assisted by female tract contractions
168
How does flagella movement work
1. In central axoneme there are pairs of outer microtubules
2. Dyneins bind to each doublet & extend their motor domains
3. Outer doublet slides over each other causing bending of axoneme
4. and thus flagella movement
169
What is wrong with these
170
Describe sperm transport through cervix
Major barrier
171
How do sperm interact with uterine tube
only 1-10% reach uterine tube
Sperm bind to epithelial cells
- renders them immotile
- prolongs their lifespan
Sperm released around ovulation
- swim towards ampulla region where fertilisation occurs
172
What are the dog ejaculate fractions
3 fractions
1st & 3rd seminal fluid
2nd sperm-rich
173
Describe sperm capacitation
1. removal of decapacitation factors
2. membrane destabilisation induced by ion movement
3. detachment from oviductal epithelium
4. transient hyperactivity
- exposure of surface proteins (ZP proteins) that can bind to oocyte
- enables acrosome reaction
174
Label the oocyte
175
What are the 3 glycoproteins in zona pellucida
ZP1 - minor component
ZP2 - structural component
ZP3 - receptos
176
What is the acrosome reaction in sperm
Occurs after capacitation
1. Initiated by sperm binding to ZP
2. Acrosomal hydrolytic enzymes released
- digest ZP & localised small hole so nucleus of sperm can be released into oocyte
3. Spermatozoa head penetrates ZP
- requires hyper-activation of flagellum
4. fusion of plasma membranes
177
How does sperm activate oocyte
178
In females what are the germ cell producing organs
ovary
179
In females what are the conducting organs
uterine body & uterus (allow germ cell transport)
180
In females what organ provides space for development
uterus
181
In females what are the copulatory organs
vagina & vestibule
182
Label the diagram
183
Describe equine ovary morphology
Large (up to 10cm)
Has ovarian fossa with germinal epithelium (cortex is in this area only)
- Follicles only rupture here
Vascular zone is peripheral
Corpus Luteum up to 50mm
184
Label the tubular structure of female reproductive tract
185
What are the 3 regions of the uterine tube
Infundibulum
- covered with fimbriae (long finger like folds that captures ooctye)
ampulla
- near ovary
isthmus
- next to uterus
186
Label the uterine tube
187
What are the functions of the uterine tube
Sperm transport & storage
catching oocyte
oocyte transport
environment for fertilisation
188
What is the difference between mare & bitch uterine tube
189
Label
Lumen may house sperm or early embryo
endometrium becomes part of placenta
190
What are the functions of the uterus
Sperm storage/transport
Production of prostaglandin F2a to control cyclical activity
Environment for early embryo
Contribution to placenta
Parturition
191
Label the uterus
192
What are the types of uteri
193
Label the cow uterus & describe it
Uterine horns curved
Uterine body short
pregnancy often in 1 horn
194
Label the sow uterus and describe it
Long uterine horns
Coiled in caudal direction
Small uterine body
195
Describe the mare ovary
Ovaries sub-lumbar & dorsal in position
Uterine horns straight
Uterine body long
196
Describe the bitch reproductive tract
Ovaries sub-lumbar
Ovaries very cranial (near kidneys)
Uterine horns short & straight
Uterine body short
197
Describe the microstructure of uterine tissue
198
What are these and what is their function
Endometrial folds
Contribute to maternal placenta
199
Label the diagram
200
Describe the function of the cervix
201
Describe cervical rings/folds in different species
Single: bitch, queen
Multiple: cow, ewe, sow
202
Describe the variable degree of patency of the cervix (important for passing catheters into uterus
Interlocking folds: cow, ewe
Spiral interlocking folds: sow
Loosely apposed folds: mare
203
What is the cervical seal of pregnancy
204
Describe the vagina subdivisions
205
What are the functions of the vagina
copulation
parturition
micturition
206
What is the fornix vagina
In cow, mare & bitch
cervix protrudes into cranial vagina forming crypt or pocket
spermatozoa deposited here during natural service
207
Label the diagram
arrow is urethral orifice
208
where does the vagina originate from
paramesonephric ducts
209
where does the vestibule form from
urogenital sinus
210
Label the clitoris
211
What is the function of the broad ligament
Support & suspend reproductive tract
Houses vascular supply, lymphatic drainage & nerves
212
What are the components of the broad ligament
213
Where is the broad ligament
214
Label the ligaments
215
Describe the round ligament of the uterus
216
Label the diagram (repro tract)
217
Label the 3 arteries
218
Describe the uterine artery
219
What is the vaginal artery a branch of
Internal iliac artery
220
Describe the ovarian artery
221
Describe the utero-ovarian counter-current transport system
222
What is the innervation of the ovary
sympathetic from mesenteric plexus
223
What is the innervation of the uterus, cervix & vagina
parasympathetic & sympathetic from pelvic plexus
224
Label the diagram
225
Define artificial insemination
Deliberate introduction of a sperm/semen sample into cervix or uterine cavity by catheter
226
Why use AI
227
How is ejaculate for AI collected
228
Why are semen examinations done
229
What do semen examinations assess
230
How do you use a haemocytometer
Place sperm in counting chamber
Only count 5 squares for estimate
Only count sperm on 2 sides of box to account for other boxes around
231
How do you count sperm with a hemocytometer
1. find middle blue square containing more squares
2. count sperm in 5 yellow boxes
3. multiply by 5 to get estimate of total number in blue square
4. multiply by 10,000
5. multiply by dilution factor if semen has been diluted
6. sperm count will be N (sperm in blue square) x10^4 = total number of sperm per ml of semen
232
Work out the sperm concentration (hemocytometer)
192x10^6 sperm/ml
233
Why would you use Nigrosine & Eosin stain to assess sperm
Visualise sperm easier
Assess membrane integrity/function
234
Describe each sperm cell
235
Name the abnormalities and why is 1 circled
236
What are the sperm preservation options
*freeze-thawing can cause sperm damage
237
What do extender solutions aim to do in sperm storage
238
What factors are important in semen preservation
239
What is the process of using cryopreserves for freeze thawing of sperm
240
Describe sperm collection & storage in the bull
241
Describe sperm storage in ram
242
Describe sperm storage in boar
243
Describe sperm storage in stallion
244
Describe sperm storage in the dog
245
Outline principle of semen sexing
Sexing based on separation of sperm based on their DNA content (X chromosomes have more DNA than Y)
1. sperm labeled with DNA florescent dye & sorting by flow cytometry
2. droplets containing spermatozoa emitting fluorescent signal acquire electrical charge
3. sperm into collection tubes by electromagnetic field
246
What are the components of the male tract & their functions
247
Label the penis cross section
248
What does the ischiocavernosus muscle do
Forces blood into corpus cavernosum & corpus spongiosum
249
Define libido
behavioural manifestation of sexual interest
250
Define intromission
entrance of penis into vagina
251
Define erection
firming & enlargement of penis
252
Define emission
movement of accessory gland fluid into male urethra to mix with sperm
253
Define ejaculation
reflex expulsion of sperm from male reproductive tract
254
What does erection require
255
What is the mechanism of erection
1. Erectile tissue is surrounded by heavy capsuled of varying thickness (tunica albuginea)
2. connective tissue trabeculae penetrate the erectile tissue & break up space into sinusoids
3. engorgement of cavernous tissue causes a blockage of venous return
256
Describe the role of helicine arteries in erection
They empty into venous sinuses
In flaccid penis, lumen of helicine arteries is obliterated by sympathetic tone of muscles in vessel walls
In erection, parasympathetic fibres inhibit (relax) longitudinal muscle fibres in helicine arteries
- blood flows into central sinusoids
- swelling
- results in compression of oblique veins
- further penile swelling
257
What happens to the bulbus glandis in an erect dog
Its an extension of the corpus spongiosum that gets large and turgid
258
Describe the neurotransmitter that drives erectile process
259
Describe an erection of a fibroelastic penis
260
Describe an erection of a musculocavernous penis
261
What part of the penis swells in different species during erection
262
Label the dog penis (not arrows)
263
What happens during ejaculation
264
What is the duration & volume of ejaculation in different species
265
What are some features of stallion ejaculation
series of jets
sperm rich fraction ejaculated in 3-4 squirts
last 5-8 squirts are at lower pressure + less sperm
266
What are some features of boar ejaculation
series of seminal fractions
267
What are some features of dog ejaculation
3 fractions
268
Define priapism
semi-permanent eraction
269
Define paraphimosis
Penis wont go back in prepuce
270
Define stiation
further stimuli will not cause immediate responsiveness
271
Define exhaustion (ejaculation)
no further sexual behaviour can be induced even with sufficient stimuli
272
Fill in the table
273
What are the components of ejaculate
274
What is the function of seminal plasma
275
What factors affect total sperm output & semen quality
276
What is the equation for total sperm output
volume x concentration
277
What are some equine venereal pathogens
278
What are some dog venereal pathogens
Canine herpesvirus 1
279
What are some cattle venereal pathogens
Bovine herpesvirus 1
Chlamydophila abortus
ureoplasma diversion
280
What are some sheep venereal pathogens
Brucella ovis
Chlamydophila abortus
281
What are some pig venereal pathogens
282
How is bloodless castration done with a burdizzo
283
How is bloodless castration done with elastrator castration pliers
284
What are the 3 techniques for surgical castration
285
What is this and on what species is it used
emasculators
cattle, sheep & pigs
286
What methods of castration are used for:
cattle, sheep, goats, pigs, camelids, horses, dogs, cats, rabbits, guinea pigs, ferrets
287
What are the legislations surrounding castration techniques
288
When examining testes what do we need to look for
symmetry, size, firmness, lumps & bumps, that neither are painful, that both are present
289
What structures are palpable through the scrotum
Epididymis, testes, spermatic cord
290
define hypoechoic
region on ultrasound that is darker than surrounding tissues
291
define hyperechoic
region on ultrasound that is lighter than surrounding tissues
292
define homogenous
uniform appearance of tissue
293
define echogenic stippling
small, bright spots seen on ultrasound
294
define sagittal plane
imaging plane that divides body into left & right (longitudinal)
295
define frontal plane
imaging plane that divides body into front and back (transverse)
296
define mediastinum testes
fibrous structure that contains rete testis (network of tubules where sperm travels before entering epididymis)
297
define parenchyma
functional tissue of testes
composed of seminiferous tubules & leydig cells
298
Label the testes ultrasound
299
What are the different breeding programmes for sheep
Selective breeding, crossbreeding, rotational breeding
300
When does puberty start in a ram and when can you start to breed with them?
Puberty at 5-8 months
sexual maturity at 7-10 months
301
Which hormones control seasonality in sheep
melatonin & prolactin
302
What are the 2 main reasons for conducting a breeding soundness examination
fertility, breeding efficiency
should be done annually at least 10 weeks prior to breeding season
303
What are the 5 Ts of ram MOT
teeth, toes, tone, testicles, test
304
Pros and cons of electroejaculation for semen collection
Can be used in animals with NMSK problems
Requires specialised equipment
305
Pros and cons of artificial vagina for semen collection
Mimics natural mating conditions
Collection success varies on individual animal behaviour
306
A sample requires diluting 1 in 80 in normal saline for its motility analysis. how would you prepare 4ml of this solution?
0.05ml semen with 3.95ml saline
307
How would you calculate daily sperm output?
concentration x semen volume x frequency of ejaculation
308
How would you calculate sperm output per gram of testes?
total sperm output/weight of testes
309
Which conditions would result in lower sperm output & reduced fertilisation ability?
low testosterone levels
disruption in GnRH, FSH or LH
cryptorchidism
environmental factors
genetic disorders
310
What are the phases of the oestrus cycle?
311
Draw a graph showing oestrogen & progesterone throughout the oestrus cycle
312
What do high levels of oestradiol stimulate
attraction of males & LH surge (trigger for ovulation)
313
What happens during pro-oetrus & oestrus
Ovarian follicles mature
Secrete increasing concentrations of oestradiol into blood
Oestrus behaviour
Follicular phase
314
What happens during metoestrus & dioestrus?
Ovarian follicles ovulate to produce 1+ corpus luteum
CL secretes progesterone into blood
Ends with luteolysis of CL by prostaglandin F2a
Follicles continue to develop but fail to ovulate
Luteal phase
315
Draw a graph showing oestrogen & progesterone during follicular & luteal phase
316
Describe the oestrus cycle
1. elevation in oestradiol & FSH leads to follicular development (follicular phase) & oestrus behaviour
2. causes surge in LH which induces ovulation
3. resultant CL secretes progesterone
4. ovary enters luteal phase
5. in absence of pregnancy, CL is lysed by PGF2a
6. progesterone levels decline
317
draw a graph of the oestrus cycle
318
What happens during ovulation
Follicle ovulates
- oocyte released
- enters oviduct
- fertilisation?
Ovary
- corpus luteum forms
- secretes progesterone
319
Which 2 hormones govern behaviour during oestrus cycle
Oestrogen & progesterone
320
What are the ovarian phases of the oestrus cycle
Follicular & luteal
321
What kind of hormones are progesterone & oestrogen
steroid hormones
322
What kind of hormones are LH and FSH
gonadotrophin hormones
323
Define polyoestrus
multiple cycles throughout the year
324
Define seasonal polyoestrus
Multiple cycles during 1 season
Long day: spring - mare
Short day - autumn - ewe
325
Define monoestrus
infrequent cycles, independent of season
326
How is seasonality controlled
1. By light detected by pineal gland
2. Activates brain centres leading to release of gonadotrophins
3. They activate ovaries stimulating development of follicles, secretion of oestrogen & progesterone
4. This influences behaviour (receptivity) & uterine environment
327
Fill in the table
328
To what animal does this hormone profile belong
mare
329
To what animal does this hormone profile belong
Ewe
Cow & sow similar
330
To what animal does this hormone profile belong
bitch
331
How long are proestrus, oestrus, ovulation, metoestrus, anoestrus & interoestrus in the bitch
332
What factors/hormones influence production & maturation of sperm in ram?
Accessory glands, testosterone, LH & FSH
nutrition, season, day length, melatonin, neoplasia, inflammation, age/sexual maturity
333
Calculate sperm concentration & total sperm output
334
Label the testes ultrasound
A = vaginal tunic, scrotum, cremaster m.
B = mediastinum
C = parenchyma
335
How can you test for presence of testicles
1. HCG sim test (stimulates gonad to release testosterone)
- Take sample
- Inject chorulon (Freeze dried HCG)
- collect another sample after 2 hours
2. ultrasound
3. palpation
