USDA Releases Fourth National Swine Study

Seventeen states and 2,230 sites participated in the Swine 2006 survey. USDA's National Animal Health Monitoring System (NAHMS) recently published results

Seventeen states and 2,230 sites participated in the Swine 2006 survey.

USDA's National Animal Health Monitoring System (NAHMS) recently published results from the first data collection period regarding swine health and management practices reported for 2006.

Details and two future survey releases will be available online at

The size of the sites surveyed was based on farm inventory of swine: small (fewer than 2,000 head), medium (2,000-4,999) and large (5,000 head-plus).

Findings include:

  • Nearly 79% of sites purchased semen for artificial insemination.

  • Age, reproductive failure and performance accounted for 75.9% of all culled females.

  • The percentage of sites that always isolate new breeding females ranged from 61.1% of large sites to 26.5% of small sites.

  • Fifty percent of large sites tested all breeding females for disease, compared to 29.4% of medium sites and 34.9% of small sites.

  • Vaccine was administered to acclimate new breeding females on 90% of large sites, 75% of medium sites and 60% of small sites.

  • Overall, sites farrowed an average of 11.5 pigs/litter, 10.5 born live and 9.4 pigs weaned/litter. Nearly 70% of pigs were weaned at 16-20 days of age.

  • Death loss was no different in nursery or grow-finish phases. The majority of nursery deaths (44.2%) and grow-finish deaths (61.1%) were due to respiratory problems. Central nervous system/meningitis (18.7%) problems ranked second as a cause of nursery deaths. Gastrointestinal problems such as hemorrhagic bowl syndrome or ileitis-related issues also ranked high as a cause of grow-finish deaths.

  • Most sows farrowed (73.4%), for all sites, were managed all-in, all-out (AIAO) by room.

  • Grow-finish operations were managed AIAO by building on 35% of sites, and AIAO by building for 52.6% of pigs produced.

  • Use of separate sites for farrowing to nursery increased as size of site increased. Overall, 41% of sites moved pigs from farrowing to a separate nursery site. Nearly 50% of sites moved pigs from the nursery to a separate grow-finish site.

  • The percentage of sites that obtained nursery pigs from just one source ranged from 66% of large sites to 89% of small sites. The percentage of sites using three or more sources to obtain nursery pigs ranged from 25.4% of large sites to 4.4% of small sites.

  • A greater percentage of small sites (55%) placed their own nursery pigs into grow-finish than did medium (36.3%) and large sites (43%).

  • For disease prevention, 80% of sites used antibiotics in feed for nursery pigs, compared to 68% of sites for grow-finish pigs. Antibiotics in feed were also used in 60% of sites for piglets before or at weaning.

  • The greatest percentage of sites vaccinated regularly against Mycoplasmal pneumonia and erysipelas (40% and 39%, respectively).

  • Overall, 70% of sites used a swine veterinarian during the last year, in 88% of large sites and 85% of medium-sized sites. Nearly half of large sites used an on-staff veterinarian.

  • Some 81% of sites restricted farm entry to staff. For sites that allowed non-employees to enter the farm, 95% were restricted to business visitors such as an electrician. When business visitors were allowed to enter swine facilities, about one-half of the sites (48.4%) required them to change into clean boots and coveralls before entering; 29.5% of sites required them to wait 24 hours or longer between farm visits, and 10.3% of sites required business visitors to shower before entering the site.

  • Livestock transport has been identified as a vector for swine pathogens. Just over half (51%) of all sites allowed trucks or trailers onto pig premises, with a larger percentage of large and medium sites (61% and 65%, respectively) permitting truck or trailer access than did small sites (46%). Large and medium sites more commonly required cleaning or disinfecting of trucks prior to entering a pig site.

  • More than 80% of all hog sites surveyed were less than three miles apart.

  • Nearly all sites (97%) used some form of rodent control, and 88% used bait or poison to control rodents.

  • When coming into contact with domestic swine, feral swine can transmit diseases such as brucellosis or pseudorabies. Twenty-five percent of large sites reported that feral swine were in their county. Nearly 70% of sites in the south reported that feral swine were in their county. Of producers on sites in counties where feral swine were observed, 16% had seen feral swine within a half-mile of the site during the previous 12 months. Only 14% of producers (sites) reported that feral swine had the potential for physical contact with their pigs.

  • For mortality disposal, nearly half were picked up by a renderer, with a third of carcasses disposed of by composting on-site.