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Reproductive management in small ruminants. M.A. Driancourt, MSD AH, R&D Pharmaceuticals. Feb 2012. Backbone of the presentation. What are the main reproductive features of Middle East sheep and goat breeds? What are the consequences on these physiological features on production? - PowerPoint PPT Presentation
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Reproductive management in small ruminants
Feb 2012 M.A. Driancourt, MSD AH, R&D Pharmaceuticals
Backbone of the presentation
1. What are the main reproductive features of Middle East sheep and goat breeds?
2. What are the consequences on these physiological features on production?
3. What are the technical options to break seasonal anoestrus?
4. What are the technical options to synchronize estrus during the breeding season?
5. How can we improve fertility?
6. How can prolificacy be improved?
3
What are the main reproductive features of Middle East sheep and goat breeds?
Awassi sheep• Display a seasonal pattern of
reproduction
• Tend to display a late puberty
• Commonly produce a single lamb (low prolificacy)
• Are good milk producers
4
What are the main reproductive features of Middle East sheep and goat breeds?
Damascus goats• Display a seasonal pattern of
reproduction, with a variable breeding season (June to Oct in Jordan or Sept to Feb in Cyprus)
• Tend to display a late puberty
• Are mildly prolific (1.5 kid per litter)
• Are good milk producers (500kg/lactation)
5
What are the main reproductive features of Middle East sheep and goat breeds?
Links between month of the year and cyclicity in sheep and goats
Month of the year
% of females in estrus
100
50
0
Jan May Sept Dec
Very seasonal breed or female
Less seasonal breed or female
anoestrusBSBS
TransitionTransition
6
What are the consequences on these physiological features on production?
The seasonal pattern of reproduction does not allow to have reproduction timed to generate milk or lamb meat when prices are highest.
The seasonal pattern of reproduction may not always fit with the periods when forage and feedstuffs are available to cover the production needs of the late pregnant and lactating ewes or the growth needs of the lambs
Low prolificacy negatively affects the income of the farmers
The random pattern of cyclicity between individual ewes of a flock does not allow to use AI (and the associated diffusion of genetic merit)
7
What are the consequences on these physiological features on production?
• Breed during anoestrus (hence “break” anoestrus)
• Synchronize estrus during the breeding season (to use AI )
• Increase prolificacy
Technical needs triggered by these physiological features
8
What are the technical options to break seasonal anoestrus?
• Use progestagen/progesterone impregnated vaginal devices
• Use the ram effect
• Use melatonin
9
What are the technical options to break seasonal anoestrus?
• Use progestagen/progesterone impregnated vaginal devices
Three types of devices are available: cronolone (20mg) impregnated sponges (Chronogest CR, MSD AH), MAP (60mg) impregnated sponges and CIDR(0.3g progesterone)
Typical treatment scheduleDay 0 Day 14 Day 17
Sponge insertion
Sponge removal and
PMSG injection
AI or mating
55h
SHEEP
If mating is used, preparation of the rams (flushing, light treatment or melatonin) and a
suitable ewe to ram ratio are needed
10
What are the technical options to break seasonal anoestrus?
•Use progestagen/progesterone impregnated vaginal devices (+ 400IU
PMSG and mating) in Awassi ewes
SHEEP
Ozyutlu et al 2010
11
What are the technical options to break seasonal anoestrus?
• Use progestagen/progesterone impregnated vaginal devices
Three types of devices are available: cronolone (20mg) impregnated sponges (Chronogest CR, MSD AH), and CIDR
Typical treatment scheduleDay 0 Day 11 Day 13
Sponge insertion
Sponge removal
AI or mating
44h
GOAT
Day 9
Prostaglandin injection and
PMSG administration
Bucks also need to be prepared!
12
What are the technical options to break seasonal anoestrus?
•Use progestagen/progesterone impregnated vaginal devices
GOAT
Parity 1
55.3%
Parity 2
73.7%
Parity 3
55.9%
Parity 4
75%
Parity 5
58.8%
400UI PMSG
50.9%
500UI PMSG
62.9%
600UI PMSG
68.1%
Prolificacy= 1.97+/- 0.8
Fertility Alpine & Saanen goats
Intervet registration files
13
What are the technical options to break seasonal anoestrus?
• Use the ram effect
Pre-requisites: • Target a breed with a light anoestrus or females
during the transition period• Ewes/goats need to be away from the rams/bucks
for at least a month • The rams/bucks need to be prepared (light
treatment/melatonin)
14
What are the technical options to break seasonal anoestrus?
• Use the ram effect
Chemineau et al 2006
Estrus and formation of normal corpora lutea do not happen immediately!
15
What are the technical options to break seasonal anoestrus?
•Use melatonin ear implants (18mg)
Control Sponge + PMSG (450IU)
Melatonin
Fertility 65% 78% 78%
Prolificacy 1.26 1.50 1.55
(Gomez et al 2006), Manchega ewes
I Implants need to be inserted between 50 and 70 days before breeding
16
What are the technical options to break seasonal anoestrus?
Submission rate
Fertility Prolificacy AI use
Progestagen sponges
+++ ++ +++ Yes
Ram effect + + + No!
Melatonin implant
++ ++ ++ No
(no synchro)
Take home message
17
What are the technical options to synchronize estrus during the breeding season?
• Use progestagen/progesterone impregnated vaginal devices
• Use of Ovsynch type protocols• Use of double prostaglandin protocols
SHEEP
18
What are the technical options to synchronize estrus during the breeding season?
• Use progestagen/progesterone impregnated vaginal devices
Three types of devices are available: cronolone (20mg) impregnated sponges (Chronogest CR, MSD AH), MAP (60mg) impregnated sponges and CIDR (0.3g)
Typical treatment scheduleDay 0 Day 14 Day 17
Sponge insertion
Sponge removal and
PMSG injection
AI or mating
55h
SHEEP
If mating is used, a suitable ewe to ram ratio needs to be respected
19
What are the technical options to synchronize estrus during the breeding season?
•Use progestagen/progesterone impregnated vaginal devices
SHEEP
Dairy
(Lacaune)
Dairy
(Manech)
Meat
(Texel, Vendeen)
Fertility 71% 52.3% 63.2%
Prolificacy 1.69+/- 0.67 1.45+/- 0.77 1.62+/-0.68
Intervet registration files
20
What are the technical options to synchronize estrus during the breeding season?
Sponges allow to obtain improved reproductive performance in Awassi ewes managed in a “3 lambings in 2 years” management system (6
breeding periods)
SHEEP
Zarkawi et al 2011
21
• Use progestagen/progesterone impregnated vaginal devices
Three types of devices are available: cronolone (20mg) impregnated sponges (Chronogest CR, MSD AH), and CIDR
Typical treatment scheduleDay 0 Day 11 Day 13
Sponge insertion
Sponge removal
AI or mating
44h
GOAT
Day 9
Prostaglandin injection and
PMSG administration
What are the technical options to synchronize estrus during the breeding season?
22
What are the technical options to synchronize estrus during the breeding season?
•Use progestagen/progesterone impregnated vaginal devices
Damascus goats
GOAT
Al Merestani et al (2003)
23
What are the technical options to synchronize estrus during the breeding season?
• Use of Ovsynch type protocols (Deligiannis et al 2005, Titi et al 2010)
SHEEP
Day 0 5 6.5 7
AIGnRHGnRH PGF2 a
50% fertility in
Greek ewes
60% fertility
in Awassi ewes
Day 0 5 6
GnRH PGF2 a Rams in
24
What are the technical options to synchronize estrus during the breeding season?
•Use of Ovsynch type protocols (Holtz et al 2008) Boer goats
GOAT
N=24/group Sponge
+ prostaglandin and 250IU PMSG 48h before sponge removal (AI 43h
later)
Ovsynch ( 4µg Buserelin on d0,
prostaglandin on d 7 and 4µg buserelin on d 9 with
AI 16h later)
% goats in estrus 100% 96%
Fertility (day 30post AI)
50% 56%
Prolificacy 1.83 +/- 0.23 1. 86 +/- 0.14
25
What are the technical options to synchronize estrus during the breeding season?
•Use of double prostaglandin protocols ( 7 to 11 days apart)
SHEEP
control Double PG
Conception (% US positive 30 days
post AI)
88% 63%
Prolificacy 1.58 1.27
Fierro et al 2011
26
What are the technical options to synchronize estrus during the breeding season?
• Vaginal sponges are the best approach• Ovsynch may be an alternative in goats• Double prostaglandin treatment reduces fertility
Take home message
When a successful synchronization is obatined,
1. Diffusion of genetic merit becomes possible (AI)
2. Breeding can be focussed on a narrow part of the year (labor efficiency)
3. Lambing is limited to a narrow time period (labor efficacy)
4. An homogeneous lamb crop is ready to be sold at a set time every year
27
How can we reach optimal prolificacy?
What is optimal prolificacy?• An homogeneous crop of twins! (no triplets)• If
1. maternal behavior of the ewe is OK!
2. Milk production of the ewe is adequate!
28
How can prolificacy be improved?
• Use PMSG at removal of progestagen/progesterone impregnated vaginal devices
• Use Androvax, a vaccine against an ovarian steroid
• Use genetic introgression of a prolificacy gene (such as Fec B) into your sheep breed
29
How can prolificacy be improved?
•Use PMSG at removal of progestagen/progesterone impregnated vaginal devices
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
5
0 375 750
Galway
Timadhite
romney
Dose of PMSG (IU)
Ovulation rate
Quirke et al 1986
30
How can prolificacy be improved?
• Use Androvax, a vaccine against an ovarian steroid
The recommended vaccination schedule is
First vaccination (2ml): 8 to 10 weeks before joining
Booster (2ml): 4 to 6 weeks before joining
The antibodies reduce negative feedback of the steroids on LH secretion. The increased frequency of LH pulses increases the proportion of double ovulations (by around 20%)
Not affecting seasonality (not inducing ovulation in anoestrous ewes)
Not synchronizing ovulation, hence compatible with mating by rams
A booster is needed every year to obtain the prolificacy increase, but may be skipped if the environment is too harsh
A vaccine against a steroid (androstenedione coupled to a carrier (bovine lactalbumin) in a DEAE adjuvant), applied as a primary and a booster on the first year of treatment.
31
How can prolificacy be improved?
• Use Androvax, a vaccine against an ovarian steroid
Prolificacy data from 27 farms in NZ
32
How can prolificacy be improved?
• Use genetic introgression of a prolificacy gene (such as Fec B) into your sheep breed
The Booroola gene (Fec B) is a major gene that has large effects on prolificacy (but not on seasonality).
Homozygous ewes and heterozygous carrier ewes display over 5 and around 3 ovulations (vs 1 for the non carriers)
This gene acts by interfering with the signalling of bone morphogenic proteins
Its position in the sheep genome is known
By crossing a specific breed with homozygous rams and then backcrossing to the initial breed, it is possible to introgress the Fec B prolificacy gene in that breed, while keeping all the production features of the breed (was done with Awassi)
33
How should fertility problems be analysed?
Questions to be asked when fertility is lower than expected
1. Is the problem physiological or pathological?
2. What evidence do I have that low fertility is only a female problem?
3. What evidence do I have that the ewes were indeed ready to be bred (i.e. cycling)
4. Was body condition of the ewes adequate for initiation and maintenance of pregnancy?
5. What were the climatic conditions in the days around ovulation and early embryonic development?
34
Conclusion : the tools to work from…
Efficient breeding at all times of
the year
Improving prolificacy
Allowing early
breeding of ewe lambs
Allows easy diffusion of
genetic merit by AI
Allows matings by
rams
Sponges Yes Yes( 10-40%)
(depending on amount of PMSG)
Yes Yes Yes (ram to ewe
ratio adapted to the season)
Melatonin implants
No? Yes (15%) No No Yes
Androvax No Yes (25%) No No Yes
Genetics Not yet If prolificacy genes are
introgressed
No No Yes
Improved nutrition
No Yes (10%) No No Yes
35
Conclusion: how to implement these tools according to your needs
• There are many tools that are available to move from extensive production systems towards more intensive ones (provided the farm technical management and food availability allow it)
• Several steps of intensification are possible (from mild such as the use of Androvax or melatonin implants to a more “European” production system using sponges to obtain three lambings in 2 years with increased prolificacy)
36
Questions?