The Impact of Overstocking and Negative Energy Balance on Quantitative Measurement of Non-typhoidal Salmonella in Periparturient Dairy Cattle

Stressful conditions in animal production facilities may exacerbate the fecal shedding and foodborne transmission of non-typhoidal Salmonella enterica subsp. enterica. Dairy cows are reservoirs of this zoonotic microorganism, and its prevalence has roughly doubled in the past decade on dairy farms in United States. Dairy cows are commonly overstocked at the feed bunk, and stressors placed on the animal prior to parturition may exacerbate Salmonella shedding. However, no studies have evaluated the impact of overstocking and metabolic stress on fecal concentrations of the pathogen. Therefore, we conducted a field trial with 120 multiparous dairy cows randomized into one of four treatment groups with different stocking densities at the feed bunk during the periparturient period as follows: US, understocked from -60 to -1 DRC; OS, overstocked from -60 to -1 DRC; USOS, understocked from -60 to -26 DRC/overstocked from -25 to -1 DRC; and OSUS, overstocked from -60 to -26 DRC/ understocked from -25 to -1 DRC. Fecal and blood samples were collected at four time points relative to calving. qPCR assays were used to quantify Salmonella invA gene and total bacterial community from fecal samples, and a subset of isolates recovered from fecal bacterial culture were characterized using pulsed field gel electrophoresis and serotyping. Serum non-esterified fatty acids (NEFA) were measured as a metabolic stress indicator using an immunoassay. Multivariable analyses were performed to test if changes in Salmonella concentrations were associated with stocking density, energy balance, or days relative to calving. From fecal isolates, three Salmonella serovars were identified, S. Cerro; Kentucky; Meleagridis. Concentrations of Salmonella increased as cows approached calving. Higher stocking densities at the feed bunk did not impact total bacterial community or NEFA; however, cows in the overstocked groups had higher Salmonella fecal concentrations. Further, cows with higher NEFA concentrations after calving had a higher likelihood of detection of Salmonella. Future farm interventions should aim to reduce environmental and metabolic stress during the periparturient period to decrease the dissemination of Salmonella to cattle, the environment, and humans.Peer reviewe

Department of Animal Sciences research and reviews: beef and sheep

Relationship of a PCR-SSCP at the Bovine calpastatin locus with calpastatin activity and meat tenderness / H. Y. Chung, M. E. Davis, H. C. Hines, and D. M. Wulf -- Effects of calpain proteolysis and calpain genotypes on meat tenderness of angus bulls / H. Y. Chung, M. E. Davis, H. C. Hines, and D. M. Wulf -- Identification of genetic markers for growth and carcass traits in beef cattle / W. Ge, M. E. Davis, H. C. Hines, and K. M. Irvin -- Relationships of polymorphisms in the bovine leptin gene with differences in beef carcass traits / K. Tessanne, H. C. Hines, and M. E. Davis -- Effects of rate of gain during periods of restricted intake on performance and carcass characteristics in steers fed to achieve step-wise increases in rate of gain / J. E. Rossi and S. C. Loerch -- Effects of feeding regimen and days fed on performance and carcass characteristics of feedlot steers / J. E. Rossi, S. C. Loerch, S. J. Moeller, and J. P. Schoonmaker -- Effect of an accelerated finishing program on performance and carcass characteristics of early weaned bulls and steers / J. P. Schoonmaker, S. C. Loerch, F. L. Fluharty, T. B. Turner, S. J. Moeller and J. E. Rossi -- Yeast-mineral mixes and beef-cattle performance in fescue-based grazing systems: preliminary report / S. Boyles, W. Shriver, and D. Kobs -- Forage and animal evaluation of heifers at Indian Lake Hydrologic Unit CRP stocker grazing demonstration / S. L. Boyles, B. W. Stoll, and T. L. Dobbels -- Beef quality is every cattleman's business: education program / J. Yates and S. Boyles -- Effects of pelleted alfalfa and whole-shelled corn combinations on lamb growth and carcass characteristics / F. L. Fluharty -- Effects of feeding pelleted, ensiled, or a combination of pelleted and ensiled alfalfa on lamb growth and carcass characteristics / F. L. Fluharty, G. D. Lowe, and D. D. Clevenger -- Effects of corn silage vs. alfalfa haylage on lamb growth and carcass characteristics in forage-based finishing systems / F. L. Fluharty, G. D. Lowe, and D. D. Clevenger -- Effects of feed-delivery system and corn processing on lamb growth and carcass characteristics / F. L. Fluharty, G. D. Lowe, and D. D. Clevenger -- Effects of pen floor type and bedding on lamb growth and carcass characteristics / F. L. Fluharty, G. D. Lowe, and D. D. Clevenger -- A PCR-SSCP polymorphism detected in the 5' flanking region of the ovine IGF-I gene / A. Yilmaz, M. E. Davis, and H. C. Hine

The Impact of Overstocking and Negative Energy Balance on Quantitative Measurement of Non-typhoidal Salmonella in Periparturient Dairy Cattle

Stressful conditions in animal production facilities may exacerbate the fecal shedding and foodborne transmission of non-typhoidal Salmonella enterica subsp. enterica. Dairy cows are reservoirs of this zoonotic microorganism, and its prevalence has roughly doubled in the past decade on dairy farms in United States. Dairy cows are commonly overstocked at the feed bunk, and stressors placed on the animal prior to parturition may exacerbate Salmonella shedding. However, no studies have evaluated the impact of overstocking and metabolic stress on fecal concentrations of the pathogen. Therefore, we conducted a field trial with 120 multiparous dairy cows randomized into one of four treatment groups with different stocking densities at the feed bunk during the periparturient period as follows: US, understocked from -60 to -1 DRC; OS, overstocked from -60 to -1 DRC; USOS, understocked from -60 to -26 DRC/overstocked from -25 to -1 DRC; and OSUS, overstocked from -60 to -26 DRC/ understocked from -25 to -1 DRC. Fecal and blood samples were collected at four time points relative to calving. qPCR assays were used to quantify Salmonella invA gene and total bacterial community from fecal samples, and a subset of isolates recovered from fecal bacterial culture were characterized using pulsed field gel electrophoresis and serotyping. Serum non-esterified fatty acids (NEFA) were measured as a metabolic stress indicator using an immunoassay. Multivariable analyses were performed to test if changes in Salmonella concentrations were associated with stocking density, energy balance, or days relative to calving. From fecal isolates, three Salmonella serovars were identified, S. Cerro; Kentucky; Meleagridis. Concentrations of Salmonella increased as cows approached calving. Higher stocking densities at the feed bunk did not impact total bacterial community or NEFA; however, cows in the overstocked groups had higher Salmonella fecal concentrations. Further, cows with higher NEFA concentrations after calving had a higher likelihood of detection of Salmonella. Future farm interventions should aim to reduce environmental and metabolic stress during the periparturient period to decrease the dissemination of Salmonella to cattle, the environment, and humans.Peer reviewe

Department of Animal Sciences research and reviews: poultry 2001

A summary of the effect of selection for increased body weight in turkeys on the immune system / Z. Li, K. E. Nestor, and Y. M. Saif -- Genetic variation in pure lines and crosses of large-bodied turkey lines. 1. Body weight, walking ability, and body measurements of live birds / K. E. Nestor, J. W. Anderson, and S. G. Velleman -- Genetic variation in pure lines and crosses of large-bodied turkey lines. 2. Carcass traits and body shape / K. E. Nestor, J. W. Anderson, and S. G. Velleman -- Mode of inheritance of the low score normal condition in chickens / S. G. Velleman and K. E. Nestor – b1 integrin expression during normal and low score normal avian myogenesis / S. G. Velleman and M. Wic