EVALUATION OF TRICKLE FEEDERS FOR GESTATING SOWS

Goals / Objectives
1. To evaluate the efficacy of trickle feeding as an alternative to the gestation crate in terms of the system effects on pregnant gilt/sow reproduction, physiology (endocrine and immune measures), behavior and overall productivity; 2. To examine trickle feeding vs. drop feeding and the interaction. between feeding system and housing system on pregnant gilt/sow reproduction, physiology (endocrine and immune measures), behavior and overall productivity.

Project Methods
Gilts (160) will be randomly assigned to one of four treatments: Gestation crate, drop fed; Gestation crate, trickle fed; Group pen, drop fed; and Group pen, trickle fed. Five (5) cycling gilts will be placed in each treatment in a given block. A total of 8 blocks will be examined. Gilts and sows will farrow in conventional farrowing crates in common rooms. Gilts will be re-bred after weaning and will be in the experimental treatments for 2 parities. Behavior data will be collected at four times throughout gestation. Immune and endocrine measures will be taken during the last trimester of pregnancy. Samples will be assayed for cortisol, lymphocyte blastogensis, natural killer cell cytotoxicity, neutrophil chemokinesis/chemotaxis and serum IgG and acute phase proteins.

Progress 03/15/02 to 09/30/04

Outputs
4. What were the most significant accomplishments this past year? D. Progress Report: This project is a Specific Cooperative Agreement between USDA-ARS, CSRL, Livestock Issues Research Unit, Lubbock, TX, and Texas Tech University. Additional details of research can be found in the report for the parent CRIS 6208-32000-002-00X, "The Emerging Issue of Sow Housing". Seventy-eight Camborough-22 (PIC USA) gilts in mid-gestation were used to determine the effects of two penning systems (crates vs. pens of five) and feeding system (drop fed vs. trickle fed) on gilt behavior, pathogen shedding, immune measures, and production of breeding and gestation effects. In conclusion, most immune measures were not influenced by the penning or feeding systems evaluated. However, neutrophil phagocytosis efficiency may be improved for crated gilts that are trickle rather than drop fed. Among penned gilts, trickle feeding reduced neutrophil efficiency compared with neutrophils from gilts that were drop fed. Overall behavioral activity levels were statistically similar among treatments. Pregnant gilts expressed different forms of activity depending on the available space. Finally, our research determined that overall productivity of breeding and gestating gilts was similar in the four systems evaluated. There was not significant difference in pathogen shedding among trickle fed sows. This project has been completed and results are being prepared for presentation and publication.

Impacts
(N/A)

Publications