|Fangman, Thomas - UNIVERSITY OF MISSOURI|
|Misfeldt, Michael - UNIVERSITY OF MISSOURI|
Submitted to: Swine Health and Production
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 15, 1996
Publication Date: N/A
Interpretive Summary: Segregated early weaning (SEW), the practice of removing baby pigs from the sows at 11-18 days of age and moving to an off-site nursery, is currently being applied by swine production units. Although this practice has been successful in units with high pathogen levels, it has not been determined if such advantages in performance can be achieved by herds practicing good sanitation and conscientious biosecurity. Relationships between two cell subpopulations of the immune system have been suggested as an appropriate indicator of immune status in SEW pigs. Two studies, one conducted at a commercial farm and the other in an environmentally controlled research facility, were conducted to assess performance and immune status for SEW pigs with low bacterial pathogen exposure. The results of these two studies suggest that production systems practicing good sanitation and conscientious biosecurity measures do not demonstrate significant performance results in SEW pigs and would not justify the additional capital and labor required to maintain the nursery production off-site. Further the results suggest that the relationship between two cell subpopulations is not an appropriate indicator of immune status in SEW pigs with low bacterial pathogen exposure.
Technical Abstract: Two experiments were conducted to evaluate the benefits of segregated early weaning (SEW) as determined by performance, by immunological status as indicated by T-lymphocyte differentiation antigens and by health status. Experiment I was conducted at a commercial herd with pigs weaned at 11 to 18 days of age and blocked by age to include 11-14 day-old pigs and 14-18 day-old pigs. Pigs were randomly assigned to three management groups: 1) on-site, commingled; 2) on-site, sanitized, and 3) off-site, sanitized. Experiment II was conducted in environmentally controlled research chambers. Pigs were weaned at 12 to 15 days of age and randomly assigned to two management groups: 1) remained in non-sanitized farrowing crates and weaned by removing the sow; and 2) weaned and transferred to a sanitized chamber and crates with access severely restricted. Performance, health, and immune status were evaluated. The results suggest that SEW may ybe a benefit to herds of low health status but not to herds of high health status and that T-lymphocyte differentiation antigens are not appropriate indicators of immune status in SEW pigs with low bacterial pathogen exposure.