Age at Puberty
Age 5-7 months
 Factors Affecting
 Weight

– 70% Mature Size

Exposure to Opposite Sex
– teasers
Positive Plane of Nutrition
 Season of Birth
 Breed

Breeding season decisions

Which Month to Breed ?
– Labor
» other enterprises

– Facilities
– Markets
– Genetics
– October best
How long to breed?
Breeding Season Management
Mature Ewes

6 weeks pre-breeding
– Condition Score
– Flush thin ewes

3 weeks pre-breeding
– flush all ewes

3 weeks into breeding
– stop flushing ?

Flushing options
–
–
–
–
.75 - 1.25 lbs. corn or
Soy hulls & DDGS
Fresh lush pasture
Turnips or other
brassicas
– Hay fields
Breeding Season
Management Mature Ewes
Body Condition
Scottish BF
Swaledale
Mule
Scottish Halfbred
UK
1.5
.79
.78
2.0
2.5
3.0 3.5
1.62
1.33 1.40 1.56
4.0
1.49 1.66 1.78 1.94 1.92
1.48 1.70 1.83 2.17 2.02
When to breed
Rambouillet, Idaho
Month
July
August
September
October
November
December
January
February
Ovulation Rate
1.00
1.60
1.72
1.80
1.86
1.88
1.89
1.57
When to breed
Suffolk crosses Oregon
Month
Ovulation Rate
July
.09
August
1.10
September
1.38
October
1.45
November
1.51
December
1.10
Breeding Management Ewes

Precautions
– Legumes
– Excess Grain

Breeding records
– marking harness
– paint/grease
– Fetal aging
Breeding Management
Ewe Lambs
huge impact on whole flock




Must expose to become pregnant
Flush or at least maintain nutrition level
Teasers - Definitely
Breed Separate
– shy breeders
– shorter estrus
– mature rams prefer mature ewes
Breeding Separate
Beginning wt
Ending wt
Conception rate
Montana State University
w/ mature drylot
no extra
83
85
84
99
0
74
Breeding Management
Ewe Lambs


Use young rams or smaller breed rams or
high survival rams
– Minimize mating problems
– Geneticly smaller for less dystocia
Breed later
– Producer observation
– Larger
– More productive
– Stretch ram power
Breeding Management
Ewe Lambs

Breed later
– Ultra sound fetal scanning
– Generation interval
– Selection pressure on reproduction
– Cull open ewe lambs
» Early selection for reproduction
» Receive market price not ewe price
Productivity
Number born
Number weaned
Pounds weaned
Lambed
@12 mo
9.6
7.5
430
Open
7.7
6.0
355
21% advantage over 6 years
11% advantage not counting year 1
SDSU
Factors Affecting Out of
Season Success

Ram libido
– High ram to ewe ratio
– Light primed rams, inc. CR 50%
Ewe age
 Ewe condition, super milked down
 Genetics
 Time
 Inputs - CIDRS, Light Priming, Regulin

Accelerated Systems

Advantages
–
–
–
–
–
–
–
–
–
spreads labor
smaller facilities
uses facilities more
uniform cash flow
better env. for lambing
utilization of pasture
ram battery utilization
market uncertainty
Breed lactating ewes

Disadvantages
–
–
–
–
–
multiple lambings
increased management
increased cost of production
shepherd burnout
lower number born/lambing
» 2.3, 2.0, 1.7
– increased mastitis
» Earlier weaning
Accelerated Systems

Every 8 months
– older weaning ages
– less mastitis risk
– not breeding in mid
summer

Star system, Cornell
–
–
–
–
7.2 month intervals
young weaning ages
poor production levels
very few star ewes
Cornell Star System
Once a year fall lambing

Advantages
– better env. for lambing
– utilization of pasture
– better prices ??

Disadvantages
– lower number born
– multiple lambings
What do you do with opens?
20-30%