ART - Small Ruminant Flashcards
What steps are involved in ET in small ruminants?
- Management and selection of donors and recipients
- Synchronization of estrus in donors and recipients
- Superovulation of donors
- Breeding (natural or AI)
- Embryo collection
- Embryo evaluation
- Transfer of embryos
How does superovulation increase the efficiency of ET?
By increasing the potential number of embryos available for recovery at the time of embryo collection
What drugs are used in superovulation in small ruminants?
Folltropin, PMSG, PG600, Eazi-Breed sheep CIDR
What FSH/LH ratio does follitropin promote?
5:1 (FSH:LH)
When is folltropin administered?
Around days 11-13 of the estrous cycle
How many injections of folltropin are required for superovulation in small ruminants?
6-8 injections decreasing dose at 12 hour intervals
What is FSH administration followed by in small ruminants?
PGF2 alpha - the same as in the cow
How many doses of PMSG is administered and with what?
A single dose in combination with FSH
What is PMSG used to do?
manipulate the estrous cycle when out of season
What is PG600 a combination of?
PMSG(FSH-like) and HCG (LH-like)
What is PG600 administered with? How many doses?
a single dose with FSH
What is PG600 used to do?
manipulate the estrous cycle when out of season
What does a CIDR do?
Releases progesterone to synchronize estrus and used during superovulation of donors
How quickly after the removal of the CIDR are small ruminants in standing heat?
24-36 hours
What is the general embryo recovery protocol?
Day 0 - CIDR in Day 4 - FSH injections start in the PM Day 6 - Remove CIDR and Prostaglandin Day 8 - Last FSH injection in AM, tease and breed AM/PM Day 9 - Breed/LAI Day 14 - Surgical embryo recovery
What is the timing for goat cervical AI?
12 and 24 hours after observed estrus
What is the timing for goat laparoscopic AI?
45-50 hours after CIDR removal
What is the iming for sheep laparoscopic AI?
48-60 hours afte CIDR removal
What tool are used to restrain donors and recipients for ET?
Cradles
How long after insemination are embryos collected?
Around 6-7 days after insemination
What should be done to prep donors for embryo recovery surgery?
All donors are taken off of feed for 24 hours and water 12 hours prior to surgery
What sedative is used for embryo recovery?
Xylazine and ketamine
How is the donor’s response to superovulation assessed?
laparoscopically
What is considered a poor responder?
if there are = 3 CL
How is embryo recovery done?
The uterus and uterine horns are exteriorized through an abdominal excision.
A foley catheter is introduced into the base of the uterine horn, threaded up the horn, and the cuff of the catheter is inflated.
Embryo flushing media is introduced through a tomcat catheter and directed down the uterine horn, towards the Foley and collected in a conical tube or filter. The procedure is repeated with the opposite horn.
What is the average number of transferable quality embryo for sheep and goats?
6-7 per flush
What are embryos evaluated for?
Size, morphology, and developmental stages - similar to bovine embryos
How many embryos can be loaded per pipette for fresh transfer?
1 or 2 embryos
What pregnancy rate can be expected from good quality embryos/
60-70% pregnancy
What are the benefits to laparoscopic ET procedure?
It is safe, minimally invasive surgical procedure. It can be performed fairly quickly. It can achieve high pregnancy rates.
What is the laparoscopic technique for embryo transfer?
Recipeints are sedated with Xylazine, placed on the cradle, and the ventral abdomen is prepared for surgery. A local lidocaine block is done. The peritoneal cavity is inflated with are and the laparascope is inserted for evaluation of the ovarian response. If adequate response, the horn is exteriorized ipsilateral to the CL and manually held. A small incision is made on the tip of the uterine horn with the backend of a curved needle. A tomcat catheter with the embryosis pushed through the incision into the lumen of theuterine horn. The embryos are deposited by pushing them through the tomcat catheter with a TB syringe. Each recipient can recieve one or two embryos ipsilateral to the ovary containing the CL
