Repro Basics (y1/2) Flashcards
Which 4 hormones stimulate mamamry growth during puberty?
Oestrogen
Progesterone
Prolactin
GH
Which organelle produces protein in mammary gland secretory cells?
Rough ER
Which organelle produces phospholipids and triglycerides in mammary gland secretory cells?
Smooth ER
Where is milk synthesised in the mammary gland?
Apical Surface
What are the 4 major components of milk in ALL animals?
Water
Protein
Fat
Lactose
Which nutrients is colostrum high in?
Fat
Protein
Vitamin A
Which nutrient is colostrum low in?
Lactose
What are the 2 stages of lactogenesis?
1: aquisition of secretory capability pre-partum
2. acquisition of copious secretion at parturition
An increase of which hormones causes stage 1 lactogenesis?
Cortisol
Prolactin
Oestrogen
Placental Lactogen
An decrease of which hormone causes stage 2 lactogenesis?
Progesterone
Which two hormones, produced from milking, maintain milk secretion?
Oxytocin and Prolactin
Apart from pituitary hormones, what maintains of milk secretion?
FIL protein
How is milk secreted through the high-resistance milk duct network?
Ejection: Myoepithelial cells push milk out
Stimulated by oxytocin
Which hormones are secreted by a developing ovarian follicle?
Inhibin
Oestrogen
Which hormones are secreted by a CL?
Progesterone
What is the GnRH pulse generator?
Hypothalamus prod GnRH –> FSH/LH from pituitary
Signals sexual maturity & repro function
What are the 3 factors in the onset of puberty?
Size/BCS
Season of birth/photoperiod
Social Cues
What is puberty in the FEMALE?
age at which a female can support a pregnancy without deleterious effects
What is puberty in the male?
Age at which ejaculate contains sufficient spermatozoa to fertilise
What are 3 physiological reasons for decreased GnRH pulse frequency?
Lactation
Pregnancy
Photoperiod
What are 3 pathological reasons for decreased GnRH pulse frequency?
Starvation
Stress
Disease
What are the two receptor types for sex steroids?
Nuclear Receptors (slow) Membrane Receptors (fast)
What are the 3 main sex steroids?
Progesterone
Testosterone
Oestradiol
Where is oestradiol produced?
Granulosa Cells of follicle
Sertoli Cells of testis
Placenta
Where is progesterone produced?
CL
Placenta
Where is testosterone produced?
Interstitial Cells of Lydig
Cells of Theca Interna
What is the male 1e action of oestradiol?
Sexual behaviour
What is the male 1e action of testosterone?
Anabolic growth
Spermatogenesis
Secretion from accessory sex glands
What is the female 1e action of testosterone?
Oestradiol synthesis
What is the male 1e action of progesterone?
Endometrial secretion
|nhibit GnRH/repro behaviour
Maintain pregnancy
What are the two functions of the ovary?
Oogenesis Endocrine Gland (oestrogens, progesterone and inhibin)
What is the role of LH? (3)
Precursors for oestrogen
Stimulations Maturation, Lutenisation and Ovulation!
Maintains CL
What is the role of FSH? (2)
Stimulates growth/recruitment of ovarian follicle
Stimulates oestrogen prod from granulosa cells
What is day 0 of the oestrus cycle?
Oestrus - when female is receptive to male
What happens in the run up to oestrus?
Progest drops
E increases
LH surge
What is prooestrus?
Follicular phase
What is oestrus?
Sexually receptive, oestrogen dominant phase
What is metoestrus?
CL-Prog dominant phase
What is anoestrus?
Reproductive inactivity - NOTHING cyclical
Which domestic animals are year-round polyoestrus?
Cow
Queen
Pig
Which domestic animals are seasonal polyoestrus?
Mare - Long Day
Ewe, Doe - Short Day
Which domestic animal is monoestrus?
Dog
Which animals are reflex ovulators?
Rabbit, Ferret
How long does a bovine CL last?
2w
How long is a bovine oestrus cycle?
21+/-3d
How long after the LH surge do cows ovulate?
1d
How long is bovine oestrus?
18h
What happens during the luteal phase of oestrus cycle in cows?
Follicular waves - until progesterone basal
What causes luteolysis in the cow/horse/sheep/pig?
Prostaglandins
How long after LH surge does ovulation occur in dogs?
2-3d
The testicular parenchyma consists of…
Seminiferous tubules Interstitial cells of leydig Capillaries Lymphatic vessels Connective tissue
What do leydig cells respond to and secrete?
Resp to: LH
Secrete: Testosterone
What do Sertoli cells respond to and secrete?
Resp to: FSH
Secrete: Inhibin
Convert testosterone to oestradiol
What is the overall role of sertoli cells?
spermatogenesis
What is the overall role of leydig cells?
Maintain secondary sex characteristics
Where does maturation of spermatids take and how long does it take to happen?
epididymis
8-15d
Name the 4 accessory sex glands of the male
Ampulla
Vesicular Glands
Prostate
Bulbourethral gland
Which nervous system dominates the control of erection?
PARA
Which nervous system dominates the control of ejaculation?
SYMP
What are the two important stages in the journey of the sperm?
Transversing the cervix
Transport to oviduct via uterus
What is capacitation?
Process in FEMALE reproductive tract where sperm become fertile.
Needed to penetrate ZP.
How long does it take spermatozoa to reach the oviduct?
2-7h
What are the 4 steps to successful fertilisation, once a sperm has reach the oocyte?
Bind to oocyte
Acrosome Reaction
Penetrate ZP
Fuse with oocyte
How does the blastocyst prevent luteolysis?
Producted IFN
Blocks oxytocin receptor synthesis
Prevents PGF release from endometrium
How is maternal recognition of pregnancy achieved in the horse?
conceptus migrates over endometrial surface
How long does attachment of the cow embryo take?
18-22d
How long does attachment of the dog embryo take?
21d
When do 50% of pregnancy losses occur in the cow?
1st 6w
What is freemartinism?
Fused placenta in cow of XX and XY foetus.
Testis secrete AMH/testosterone.
Prevents female UGT development.
STERILE adult F.
Which hormone is obligatory for pregnancy maintenance?
Progesterone
What is unique abaout the equine placenta and its hormonal maintenance of pregnancy?
Produces eCG: maintains CL and stimulates accessory CL formation
A peak of which hormone signals periparturient period?
Eostrogen
How is oestradiol stimulated in late gestation?
Foetal crowding Foetal ACTH Foetal Cortisol Oestradiol/PGF/Relaxin Parturition
What is the role of relaxin in late gestation?
softening of cervix
inc elasticity of pelvic ligaments
What is the role of oestradiol in late gestation?
inc mucus secretion
inc myometrial contraction
What are the 3 stages of parturition?
Contractions & cervical dilation
Expulsion of foetus
Expulsion of foetal membranes
What are the two reflexes involved with stage 2 parturition?
Neuroendocrine: oxytocin
Spinal: abdominal straining
What is the fergusons reflex?
Myometrial contraction Stimulate hypothalamus
PP stimulated
Oxytocin released
Inc uterine contraction
POSITIVE FEEDBACK LOOP!
Which drug inhibits prolactin? (Galastop)
Carbergoline (galastop)
When is galastop used in bitched?
Induce oestrus/abortion
Treat false pregnancy
How does cabergoline work?
Dopaminergic agonist
What are the side effects of cabergoline?
V+
Drowsiness
Transient hypotension
What are the two pharmaceutical uses for oxytocin?
Milk Let Down
Inducing myometrial contraction
What is a potential AE of oxytocin use?
Cause/complicate uterine dystocia
Which androgen is used to treat immune mediated disease?
Danazol
Which androgen is used to increase appetite, EPO and protein synthesis? (esp in CKD cats)
Nandrolone
Name 5 potential adverse effects when using androgens?
Infertility Perianal Adenomas Prostatic disorders Hepatotoxicity Masculinisation
Name 2 androgen inhibitors and which disease they treat.
Finasteride/Osaterone
BPH in dogs
What is the MOA of finasteride?
Prevents formation of dihydrotestosterone
What is the MOA of osaterone?
Blocks androgens binding to prostatic receptors
Which drug, used to treat USMI, must NOT be used in entire bitches?
Oestriol
Which synthetic progesterone can be given to synchronise oestrus in pigs/horses?
Altenogest (regumate)
Which synthetic progestogen is used to decrease hypersexual behaviour in dogs and how?
Delmadinone (tardak)
Inhibits FSH/LH to decrease testosterone
Which drug is used to treat false pregnancy in cats/dogs/ferrets?
Proligestone (synth progestogen)
What is Aglepristone used for?
Abortion, induction of parturition and pyometra
ONLY cats and dogs
Name 3 common synthetic GnRH products?
Gonadorelin
Buserelin (analogue)
Deslorelin (analogue)
Which drugs should be used to induce ovulation or synchronise oestrus?
GnRH agonists
Which drug can be given as a slow-release implant in the mare to induce ovulation?
Deslorelin
Which drugs should be used to chemically castrate pigs?
GnRF vaccine (GnRH antibodies)
Takes 1w post 2nd vac to work.
Which drug is used to induce superovulation in donor cows?
FSH
Which drug is used to induce oestrus in mares alongside progesterone implants?
PMSG/ECG
what drug can we use to treat post-partum anoestrus of the pig? Potential AE?
eCG + hCG
Anaphylaxis!!
Which prostanoid can be used to synchronise dairy cow oestrus for AI?
Dinoprost
Which prostanoid can be used to induce luteolysis in cattle and horses?
Colprostenol
What care must be taken when using prostanoids?
WEAR GLOVES - absorbs through skin
Which drug would we use to shorten the life of the CL?
PGF2a
Which drug would we use to lengthen the life of the CL?
Progesterone
What is the MOA of clenbuterol?
B2 agonist - dilates airway & relaxes myometrium
List 4 common uses of clenbuterol in the cow.
Delay delivery
Aid obstetric manouvres
Relax uterus for C section
Replace prolapsed uterus
How is melatonin used in sheep?
Advance the breeding season
What effect does increasing melatonin have on short-day breeders?
Stimulates reproduction via GnRH
What effect does increasing melatonin have on long-day breeders?
Represses Reproduction
What is the size of the equine follicle at ovulation?
> 35mm
Which cells are predominant in vaginal cytology of the bitch during anoestrus?
Parabasal cells (round cytoplasm, large nucleus)
Which cells are predominant in vaginal cytology of the bitch during proestrus?
Cornified cells (angular cytoplasm, small nucleus)
Which drug can be used to shorten the luteal phase of oestrus?
PGF2a
Which drug can be used to extend the luteal phase of oestrus?
Progesterone
Which drugs are given & when during an OvSynch protocol?
Day 0: GnRH
Day 7: PGF2a
Day 9: GnRH
Day 10: AI
What is the fixed-time AI protocol for heifer synchronisation?
PGF2a - 2 doses 11d apart then AI at 72&96h or 84h
Name 2 devices used to suppress GnrH during anoestrus.
CIDR & PRID
Contain progesterone
When can you diagnose pregnancy via rectal palpation in the :
Horse?
Cow?
Horse: 20-30d
Cow: 35d
When can you diagnose pregnancy via US in the cow?
28-30d
When and how is parturition induced in the sow?
Day 114 with PGF2a - birth within 36h
How and when can you induce abortion in the Mare?
Fluprostenol at 35d
How and when can you induce abortion in the bitch?
Oestradiol on D3 & 5
How and when can you induce abortion in the cow?
PGF2a on d6-150
What is the most common cause of structural defects at birth in cattle?
Schistosoma reflexus
What is the most common indication for a caesarean in sheep?
Ringwomb
What is the most common direction for a uterine torsion to occur?
Anticlockwise (75%)
From what age can mares be used to breed?
2yo
How much light per day should a breeding mare have?
16h
How long will an artificial lighting regime take to have an effect on a mare?
60-90d
What is the mean length of an oestrus cycle in the mare?
21d
What is the average gestation length of the mare?
341d (+/-2w)
What should be done if a twin pregnancy is discovered in a mare?
Destroy smaller twin at d16 or give abortive agent at d35.
What is the earliest time for +PD via US in a mare?
11d
What is the earliest time for +PD via eCG mesaurement in a mare?
40d
In which breed of horse is AI prohibited?
TB
What are the 3 stages of spermatogenesis?
- Mitosis
- Meiosis
- Differentiation
What are the 4 phases of the differentiation stage in spermatogensis?
Golgi
Cap
Acrosomal
Maturation
How does the acrosome help the sperm to penetrate the ZP?
Contains hydrolytic enzymes
How long does Spermatogenesis take in the bull?
54d
How long does Spermatogenesis take in the stallion?
58d
How long does Spermatogenesis take in the ram?
49d
How long does Spermatogenesis take in the boar?
34d