|Donoghue, Ann - Annie|
Submitted to: Food Safety Consortium Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 9/30/2003
Publication Date: 10/2/2003
Citation: Vincente, J.L., Tellez, G.I., Nava, G., Higgins, S., Donoghue, A.M., Donoghue, D., Hargis, B.M. 2003. Evaluation of horizontal transmission of salmonella enteritidis to broiler chicks placed on acidified litter. [abstract]. Food Safety Consortium Proceedings. 2003 CDROM. Interpretive Summary:
Technical Abstract: Salmonella can be transmitted to chicks through contaminated litter. Two experiments were conducted to evaluate the effectiveness of a Sulfuric acid (SA) product to reduce the horizontal transmission of Salmonella enteritidis (SE) in broiler chicks. Two different levels of SA-base product was evaluated, low level (LL [815g/2.27m2]) and high level (HL [1631g/2.27m2]) which was spread manually on the top of the litter one day before each experiment started. In Exp. 1, used pine shavings (23% moisture) were used. Three hundred day of hatch broiler chicks from a commercial hatchery were obtained and divided in three groups (control, LL, and HL) with four replicate pens per treatment. Sixty chicks (seeders) were gavaged with 7.5 x 10^3 cfu/ml of SE resistant to Novobiocin and nalidixic acid antibiotics and held in a separate pen. Two hundred-forty chicks were placed immediately in the pens containing the SA (20 chicks/pen). Twenty-four hours later, 5 seeders were placed in each pen. At day 11, ten contact chicks per pen and the seeders were humanely killed. Cecal tonsils were aseptically removed and cultured for SE isolation following 24-h tetrathionate enrichment with subsequent plating on BGA agar containing antibiotics. Application of either LL or HL of SA prior to chick placement reduced (P< 0.05) SE transmission in Exp. 1 (used litter) as compared to controls (Control: 28%, LL: 0%; HL: 3%) 11 days after placement. At day 21, very low levels of SE were detected in all groups. Chicks placed on HL of SA had and increased (P< 0.05) body weight at 21 days. Similarly, application of the SA-based product to new litter in Exp. 2 reduced (P< 0.05) SE recovery from ceca of chicks cultured at 11 days (Control: 46%; LL: 23%; HL: 18%) but no difference (P> 0.05) in recovery was noted by day 21. Body weights through 21 days were unaffected by the SA product treatment of new litter. These data suggest that SA treatment of new or used litter may reduce early horizontal transmission of Salmonella. Enhanced 21-day performance of chicks on used litter treated with SA may suggest that other low-level pathogens were reduced by treatment, although further studies are necessary to confirm and extend these findings.