Evaluating a natural outbreak of porcine proliferative enteropathy and treatment with tylosin in the grow-finish phase
Melissa Fleck Veenhuizen, DVM, MS; Daniel H. Mowrey, PhD; Gregory M. Moore, DVM; Lee E. Watkins, PhD
Complete article is available online.
PDF version is available online.
Objective: To determine approximate time and severity of a porcineproliferative enteropathy (PPE) outbreak in a herd with a history of PPE;to compare average daily gain (ADG), average daily feed intake (ADFI), feedefficiency (F:G), and clinical impression of disease in clinically affectednonmedicated controls versus pigs medicated with 110 ppm (100 g per ton)of tylosin for 21 days followed by 44 ppm (40 g per ton) tylosin for anadditional 21 days; and to follow pigs to market to determine effects ofthe outbreak on clinical PPE lesions detected at slaughter.
Methods: One hundred and twelve pigs with clinical signs of PPEwere randomly assigned to either a control group receiving nonmedicatedfeed or to a medicated group receiving feed with 110 ppm (100 g per ton)of tylosin for 21 days. The feed of the medicated group was then changedfrom 110 to 44 ppm (100 g to 40 g per ton) tylosin for another 21 days.Then all pigs (in both medicated and control groups) were placed on 22 ppm(20 g per ton) tylosin (for growth promotion) until market. Average dailygain, ADFI, and F:G were compared for the first 21-day phase, the second21-day phase, and throughout the 42-day trial period. Pigs were also ratedwith a clinical impression score (CIS) ranging from 0 = clinically normalto 3 = severely infected for the first 21-day phase.
Results: Clinical impression scores improved more rapidly in medicatedpigs than in nonmedicated controls during the first 21 days. Growth performance,although it tended to be improved for ADG (P <.09) and F:G (P<.07), did not differ significantly between treatment groups in the first21-day phase, in the second 21-day phase, or for the overall trial period.
Implications: Tylosin in this study was effective in treatingPPE when administered at a dosage of 110 ppm (100 g per ton) for 21 days.There was no significant advantage to medicating pigs with 44 ppm (40 gper ton) tylosin for an additional 21 days. Ileal thickening at slaughterwas observed in 26% of the pigs in this study, suggesting that palpationof ileal thickening at slaughter may detect previous PPE outbreaks.
Keywords: porcine proliferative enteropathy, Lawsonia intracellularis, tylosin
Cite as: Veenhuizen, MF, Mowrey DH, Moore GM, et al. Evaluating a natural outbreak of porcine proliferative enteropathy and treatment with tylosin in the grow-finish phase. J Swine Health Prod 1998;6(2):67-72.
Search the AASV web site for pages with similar keywords.