Callaway T.R.,U.S. Department of Agriculture |
Edrington T.S.,U.S. Department of Agriculture |
Brabban A.,Evergreen State College |
Kutter B.,Evergreen State College |
And 9 more authors.
Foodborne Pathogens and Disease | Year: 2011
Salmonella is a foodborne pathogenic bacterium that causes human illnesses and morbidity and mortality in swine. Bacteriophages are viruses that prey on bacteria and are naturally found in many microbial environments, including the gut of food animals, and have been suggested as a potential intervention strategy to reduce Salmonella levels in the live animal. The present study was designed to determine if anti-Salmonella phages isolated from the feces of commercial finishing swine could reduce gastrointestinal populations of the foodborne pathogen Salmonella Typhimurium in artificially inoculated swine. Weaned pigs (n=48) were randomly assigned to two treatment groups (control or phage-treated). Each pig was inoculated with Salmonella Typhimurium (2×10 10 colony forming units/pig) via oral gavage at 0h and fecal samples were collected every 24h. Swine were inoculated with a phage cocktail via oral gavage (3×10 9 plaque forming units) at 24 and 48h. Pigs were humanely killed at 96h, and cecal and rectal intestinal contents were collected for quantitative and qualitative analysis. Fecal Salmonella populations in phage-treated pigs were lower (p<0.09) than controls after 48h. Phage treatment reduced intestinal populations of inoculated Salmonella Typhimurium in pigs compared to controls at necropsy. Cecal populations were reduced (p=0.07) by phage treatment >1.4log 10 colony forming units/g digesta, and rectal populations were numerically reduced. The number of pigs that contained inoculated Salmonella Typhimurium was reduced by phage treatment, but a significant (p<0.05) reduction was only observed in the rectum. We conclude that phages can be a viable tool to reduce Salmonella in swine. Further research needs to be performed to determine the most efficacious dosing regimens and the most effective combinations of phages targeting the diverse Salmonella population found in swine before they can enter the food supply. © Copyright 2011, Mary Ann Liebert, Inc. 2011.
Knauer M.T.,North Carolina State University |
Hostetler C.E.,National Pork Board
Journal of Swine Health and Production | Year: 2013
Objective: To quantify US swine production trends for sow-farm and grow-finish traits from a large available database. Materials and methods: Data were provided by a data management company, representing annual production of approximately 1.8 million sows in the United States. Sow-farm traits included pigs per mated female per year, litters per mated female per year, total number born, number born alive, number weaned, preweaning mortality, weaning age, weaning weight, replacement rate, culling rate, sow mortality, lactation-feed intake, and gestation-feed intake. Grow-finish traits included entry age, entry weight, exit age, exit weight, average daily gain, feed efficiency, caloric efficiency, and mortality. Results: From 2005 to 2010, pigs per mated female per year, litters per mated female per year, number born alive, number weaned, weaning age, weaning weight, and lactation-feed intake increased (P <. 05). Sow mortality decreased (P <. 05) and replacement rate did not change [P >. 05). Entry age and entry weight increased (P <. 05) for nursery and wean-to-finish pigs. Average daily gain improved for nursery and finishing production (P <. 05), but not for wean-to-finish (P >. 05). No improvements were made for finishing caloric efficiency (P >. 05), and wean-to-finish caloric efficiency worsened (P <. 05). Mortality for both finishing and wean-to-finish operations improved (P <. 05). Implications: Both scientists and producers can use these results to better understand US sow-farm and grow-finish production levels. Pig industry trends from 2005 to 2010 indicate varied degrees of improvement for pig production traits.
Knauer M.,Iowa State University |
Stalder K.J.,Iowa State University |
Serenius T.,Iowa State University |
Baas T.J.,Iowa State University |
And 8 more authors.
Journal of Animal Science | Year: 2010
The purpose of this study was to determine the association of production factors with stayability to parity 4 (STAY4) under controlled experimental conditions. Data were from 2,293 female pigs, sampled from 6 genetic lines that were entered into the National Pork Producers Council Maternal Line National Genetic Evaluation Program. Genetic lines evaluated included Newsham (NH), National Swine Registry (NSR), American Diamond Swine Genetics (ADSG), Danbred (DAN), and 2 Dekalb-Monsanto lines (DK44 and GPK347). Stepwise logistic regression was utilized in the analysis of STAY4. All effects were nested within genetic line. Categorical effects in the model were arrival date to the wean-to-finish unit (entry date) and breed-gestation-farrowing facility (farm). Continuous effects in the model were gilt backfat, LM depth, ADG, age at puberty, age at first farrowing, and traits recorded before the last litter of the sow (prefarrow backfat, number born alive, number weaned, litter weaning weight, lactation feed intake, lactation backfat loss, and lactation length). Factors significant for STAY4 included farm, entry date, age at first farrowing, ADG, gilt backfat, and lactation before removal effects, as well as feed intake, number born alive, and lactation length. Age at first farrowing and lactation feed intake affected all genetic lines. Regression coefficients for STAY4 on age at first farrowing were -0.014, -0.022, -0.017, -0.016, -0.011, and -0.021 (all P < 0.05), respectively, for NH, NSR, ADSG, DK44, GPK347, and DAN genetic lines. Regression coefficients for STAY4 on lactation feed intake were 0.043, 0.049, 0.051, 0.061, 0.120, and 0.097 (all P < 0.05), respectively, for NH, NSR, ADSG, DK44, GPK347, and DAN females. Age at puberty, age at first farrowing, and lactation feed intake had the greatest effect on STAY4. © 2010 American Society of Animal Science.
Moeller S.J.,Ohio State University |
Miller R.K.,Texas A&M University |
Edwards K.K.,Texas A&M University |
Zerby H.N.,Ohio State University |
And 5 more authors.
Meat Science | Year: 2010
The study evaluated the interactive and individual effects of fresh pork loin (n = 679) ultimate pH (pH), intramuscular fat (IMF), Minolta L* color (L*), Warner-Bratzler shear force (WBS), and four cooked temperatures (62.8 °C, 68.3 °C, 73.9 °C, and 79.4 °C) on consumer (n = 2280) perception of eating quality (n = 13,265 observations). Data were analyzed using ordered logistical regression. Predicted mean responses were consistently near or under five on the 1-8-point end-anchored scale, indicating a neutral perception of pork eating quality regardless of fresh quality or cooked temperature. Responses improved as IMF and pH increased and WBS decreased, whereas L* did not contribute significantly to variation in responses. Increasing IMF resulted in a very small incremental improvement in responses, but was of practical size only when comparing the least (1%) to the greatest (6%) levels. Loin pH and WBS were primary contributors to consumer perceptions, whereby an incremental increase in pH (0.20 unit) and decrease in WBS (4.9 N) resulted in a 4-5% reduction in the proportion of consumers rating pork as ≥6 (favorable) on the 8-point scale. No interactions between quality and temperature effects were observed. Increased cooked temperature was negatively (P < 0.05) associated with Overall-Like and Tenderness ratings, but the incremental effect was small. Juiciness-Like and Level responses decreased by 0.50 units as temperature increased across the range. Consumer responses favor pork with lower WBS, greater pH and IMF, and pork cooked to a lower temperature. © 2009 Elsevier Ltd. All rights reserved.
Nikkila M.T.,Iowa State University |
Stalder K.J.,Iowa State University |
Mote B.E.,Iowa State University |
Rothschild M.F.,Iowa State University |
And 5 more authors.
Journal of Animal Science | Year: 2013
The objective of this study was to estimate genetic associations for gilt growth, compositional, and structural soundness with sow longevity and lifetime reproduction. Performance and pedigree information from 1,447 commercial females from 2 genetic lines were included in the data analyzed. Growth was expressed as days to 113.5 kg BW (DAYS) and compositional traits included loin muscle area (LMA), 10th rib back fat (BF10), and last rib back fat (LRF). Structural soundness traits included body structure traits [length (BL), depth (BD), width (BWD), rib shape (BRS), top line (BTL), and hip structure (BHS)], leg structure traits [front legs: legs turned (FLT), buck knees (FBK), pastern posture (FPP), foot size (FFS), and uneven toes (FUT); rear legs: legs turned (RLT), leg posture (RLP), pastern posture (RPP), foot size (RFS), and uneven toes (RUT)], and overall leg action (OLA). Lifetime (LT) and removal parity (RP) were considered as longevity traits whereas lifetime reproductive traits included lifetime total number born (LNB), lifetime number born alive (LBA), number born alive per lifetime day (LBA/ LT), and percentage productive days from total herd days (PD%). Genetic parameters were estimated with linear animal models using the average information REML algorithm. Second, to account for censored longevity and lifetime reproduction records, genetic parameters were estimated using Markov Chain Monte Carlo and Gibbs sampling methods. Similar estimates were obtained across the analysis methods. Heritability estimates for growth and compositional traits ranged from 0.50 to 0.70 and for structural soundness traits from 0.07 to 0.31. Longevity and lifetime reproductive trait heritability estimates ranged from 0.14 to 0.17 when REML was used. Unfavorable genetic correlations were obtained for DAYS with LT, RP, LNB, LBA, and PD% and for LRF with PD%. However, LMA was favorably associated with LT, RP, and LNB. Moderate to high correlations were obtained for BL and BRS with all longevity and lifetime reproductive traits. Correlations of BWD with LT and RP were moderate. Associations for leg soundness traits with longevity and lifetime reproductive traits were mainly low and nonsignificant (P ≥ 0.10). However, RLP was moderately correlated with LBA/LT and PD%. Current results indicate that selection for fewer DAYS has an antagonistic effect on lifetime performance. Furthermore, great BL, fl at BRS, narrow BWD, and upright RLP seem detrimental to sow longevity and lifetime reproduction. © 2013 American Society of Animal Science. All rights reserved.