Part of five topic presentation for New River Sheep & Goat Club. February 20, 2016.

1. Increasing the
birthing rate
SUSAN SCHOENIAN
SHEEP & GOAT SPECIALIST
UNIVERSITY OF MARYLAND EXTENSION
SSCHOEN@UMD.EDU – SHEEPANDGOAT.COM – WORMX.INFO

2. Increasing the birthing rate
• Do you know what your last birthing percentage was?
• What percentage of your lambs/die before weaning?
• What is your primary reason for culling ewes/does?
Tips for improving lambing/kidding percentages
http://www.slideshare.net/schoenian/tips-for-improving-lambingkidding-percentage

3. In 2015, the national average lambing late
was 111 lambs per 100 ewes (USDA, 2016).
THAT
SUCKS!

4. In Virginia, the average lambing rate was
116% in 2015 and 104% in 2014 (USDA, 2016).
THAT
STILL
SUCKS!

5. Are goat producers doing a better job?
Don’t know.
Maybe, maybe not.
Per doe kidding Average
Number born n=3057 1.84
Number weaned n=2906 1.56
Source: Kentucky State University GHIP FEB 2015

6. What is lambing/kidding percentage?
• NOT: # lambs born per ewe lambing
• NOT: # lambs born per ewe exposed
• NOT: # lambs weaned per ewe lambing.
• NOT: # lambs weaned per ewe exposed
• NOT: # lambs marketed* per ewe lambing
*sold or retained for breeding

7. Lambing percentage is # lambs
marketed (or retained) per ewe exposed.
100 ewes exposed to ram(s)
95 ewes lambed (1-2 heat cycles)
170 lambs born live
160 lambs weaned
150 lambs sold/retained
# lambs
Per ewe
lambing
Per ewe
exposed
# lambs born 1.79 1.70
# lambs weaned 1.68 1.60
# lambs marketed 1.58 1.50

8. Lambing/kidding percentage
is a composite trait.
1-Fertility (conception) + 2-Litter size (ovulation rate + embryo survival) + 3-Survival

9. Many factors affect birthing percentage.
 birthing percentage
• Breeding during normal breeding season
• Prolific genetics
• Crossbred lambs have higher survival
• First cross ewes have higher birthing
percentage
• Postnatal loss < 10 percent
• Optimal nutrition
• Body condition score of > 3
• Cull open ewes/does
• Cull underperforming ewes/does
• Disease prevention and treatment
• Aggressive, fertile rams and bucks
• Accelerated lambing/kidding
• Match reproductive rate to labor and
management
 birthing percentage
• Breeding outside of normal breeding season
• Lack of selection for prolificacy
• Straight bred lambs have lower survival
• Straight bred ewes have lower lambing
percentage.
• Postnatal loss > 10%
• Sub-optimal nutrition
• Body condition score of < 2.5
• Keep open ewes/does
• Keep underperforming ewes/does
• Lack of disease prevention and treatment
• Lazy, gay, and infertile rams and bucks
• Annual lambing/kidding
• Mismatch of reproductive rate to labor and
management.

10. Season of breeding and birth
• Estrus in ewes and does is triggered by
photoperiod. Sheep and goats are short-day
breeders.
• While some sheep and goats are less seasonal,
reproductive rates are almost always maximized
when breeding and birthing times are matched to
what is most natural for sheep and goats.
• With fall breeding, most females will conceive
in their first 17-21 days, resulting in a more
concentrated lambing/kidding period.
• Winter and fall lambing rates will be lower than
spring lambing rates.

11. Nutritional effects on reproduction
• Ewes/does in better body condition will ovulate more eggs.
• Thin ewes/does (BCS <2.5) can be flushed to increase ovulation
rate. Flushing is when you increase the nutrient intake (cause female
to gain weight) prior to and during the early part of breeding
season, e.g. 0.5 lb. grain per head per day or better quality pasture.
• Obese (BCS >4.5) females have higher embryonic loss.
• Obese (BCS >4.5) females have more problems during the
periparturient period, e.g. pregnancy toxemia, prolapses, dystocia.
• Improper nutrition during late gestation can cause many problems,
i.e. pregnancy toxemia, milk fever, dystocia, over or undersized
offspring, etc.
• Aim for a body condition score of 3/5 at the time of breeding and
parturition.

12. Cull underperforming females
It costs just as much to feed a ewe with a single as one with twins.
• Open/barren
• Fails to wean a lamb or kid
• Fails to raise twins for two
years in a row.
• Lambs or kids outside of normal
lambing/kidding season
• Only milks on one side
• Poor milk producer
• Raises poor quality offspring
• Physical defects that prevent female
from raising profitable litters, e.g. age
(teeth, BCS).
• Don’t make excuses for ewes/does
• No lamb(s)/kid(s) – no $$$$$

13. Two ways to use genetics to
improve reproductive rate
Selection
• Use rams/bucks that were born/raised
as multiples from most productive
families on farm.
• Use ram(s) with above-average EBVs
for number born/weaned.
• Select replacements born/raised as
multiples from most productive
families in flock/herd.
Crossbreeding
• Choose a more prolific dam breed
e.g. St. Croix, Katahdin, Polypay
• Introduce a more prolific dam breed
e.g. Finn, Romanov
• Crossbred to improve fitness and
fertility.
• Don’t save replacements from terminal
sire matings, e.g. Texel, Dorper

14. Two advantages to crossbreeding
Breed complementarity
• Balance strengths and
weaknesses of different breeds,
e.g. ♂ Texel x ♀ Katahdin
Hybrid vigor
• Higher survival of crossbred offspring
• Superior performance of crossbred female

15. Accelerated lambing/kidding
Decreasing lambing/kidding interval to less then 12 months.
Systems
• Twice a year
• Continuous, opportunistic
no defined breeding seasons.
• Every 8 months - 2 times/3 years
• Overlapping 2 times/3 years
• STAR® system - 5 times/3 years
Characteristics
• Spread out fixed costs
• More efficient use of facilities
• Year-round marketing
• Better cash flow (for bank!)
• Increased profitability [?]
But . . . management/labor intensive
Challenge . . . out-of-season breeding

16. Breeding ewe lambs and doe kids
Management
• Breed at 7 to 9 months of age to
lamb/kid at 12-14 months of age.
• Only if well-grown: 2/3rds of their
mature weight at time of joining.
• Should be fed and managed separately
until they wean their first litter or are
bred for the second time.
• Increased flock productivity. $$$$
no “free loaders” except for males!
• Greater lifetime production of females
• Reduce generation interval
Accelerate genetic improvement
CONS: Yearlings have more problems
during the periparturient period. There is a
possible delay in growth.
Advantages

17. Don’t forget the boys!
• Rams/bucks need good nutrition, health care, and management
year-round.
• Don’t wait until last minute to get new ram or buck.
• Should perform breeding soundness exam prior to breeding
season (physical exam + semen evaluation)
• Use marking harness or rattle paint to monitor breeding activity,
especially in single-sire flocks.
• Males often require supplemental feeding during breeding
season.
• Fertility is highest during normal breeding season (fall). Males
of some breeds could be limiting factor in accelerated
lambing/out-of-season breeding programs.
Remember that male contributes 50% of genetics to
flock, over 90% after several years of use.

18. Thank you for your attention.
Do you have any
questions or comments?
SUSAN SCHOENIAN
Sheep & Goat Specialist
University of Maryland Extension
sschoen@umd.edu
sheepandgoat.com