Some Neat Reproduction Numbers from NAHMS
by
Dr. Tim Safranski
State Swine Breeding Specialist
University of Missouri-Columbia
(573)
884-7994
If you have not had a chance to look over the most recent
NAHMS report put together by the USDA APHIS (Swine 2000 Part I: Reference of
Swine Health and Mangaement in the United States), there are some interesting
numbers in there for Missouri producers. The
National Animal Health Monitoring System, or NAHMS, has put together these
surveys for swine production three times now. The most recent one surveyed farms from the top 17 swine
producing states (Missouri is 6th, in case you didn’t know).
Artificial insemination was the most frequent mating method
on farms. For the first mating
68.6% of sows were mated by AI, and the number rose to 72,3% for second matings.
This varied by size of operation. On
farms with a female inventory of less than 250 pen mating was most prevalent at
69.1%, and use of AI for first and second matings was most common on farms with
500 or more females in inventory being used for 85.3% of matings.
Farms between these sizes used double AI for about half the matings, and
various combinations of AI and hand mating or pen mating were used for the other
females. Of the smallest category,
only 12.1% of sites used AI at all, while 61.4% and 91.3% of the intermediate
and larger categories, respectively used AI.
The use of AI did not necessarily mean that each farm had
its own boar stud. Semen source was
categorized as purchased, collected on site or collected off-site (the farm
maintained the boars separately form the sows). Several farms used a combination of sources, with percentages
acquiring semen from each source at 72.9, 17.1 and 20.8%, respectively.
Data on breeding female death or culling looked fairly
positive. It must be noted,
however, that data were from December 1, 1999 through May 31, 2000, and higher
mortality rates might be expected in late summer in parts of the country.
Nonetheless, mortality rates ranged from 2.5% to 3.7% and favored the
smaller sow inventory category. Culling
during the period ranged from 15.0% to 20.3%.
The mortality and culling numbers could be doubled to approximate annual
numbers, again remembering that we might expect worse averages during the late
summer months. The primary reason
given for culling breeding age females was their age (41.9% of females).
Other popular reasons were reproductive failure (21.3%), lameness (16.0%)
and performance (12.0%) with 8% uncategorized.
Health of the sow herd is critical to production and has
been written about extensively by the veterinary community.
Results of the NAHMS study were very interesting regarding the use of
quarantine procedures for incoming animals.
Over all size categories 16.9% of farms never used an isolation or
quarantine procedure for incoming females, and 20.2% never isolated incoming
boars. The use of isolation
procedures for females was always practiced by about 1/4 of the smallest farms,
just over half of the medium category and about 2/3 of the largest farms.
Those numbers were somewhat larger for incoming boars.
The duration of isolation for sites utilizing isolation procedures
averaged between 31.8 and 51.1 days. Most
veterinary guidelines I have seen in writing suggest a minimum of 60 days.
On-farm production of replacement females was practiced by 48.5% of farms
in the smallest category, while only 9.8% of the largest farms used this
procedure.
For farms using isolation procedures, nearly all vaccinated
females while in isolation (84.1%). Additional
practices used for acclimation included exposure to culls (49.0%), and feedback
of manure from other pigs (25.1%). A
smaller proportion of farms also used feedback of mummies, placentas or
stillborns (11.3%) or exposure to sick pigs (7.7%).
Because an efficient isolation and acclimation procedure can have such a
dramatic effect on reproductive performance of the herd, producers should work
closely with their veterinarian to develop a good procedure for their farm.
There is a tremendous amount of other descriptive information in this report, but not enough room to report it here. Additional information on breeding animals includes more details about health procedures, facility types by phase and much more. Additionally the report includes a lot of information about nurseries and finishers. If you’re interested in viewing the entire report it is available online at http://www.aphis.usda.gov/vs/ceah/cahm/Swine/swine.htm or contact the
Centers for Epidemiology and Animal Health
USDA:APHIS:VS, attn. NAHMS
555 South Howes
Fort Collins, CO 80521
or e-mail them at NAHMSweb@aphis.usda.gov