Animal Sciences Commons^™

Apparent Townsend’S X Black-Throated Green Warbler (Setophaga Townsendi X Virens) Hybrids In Kansas And Nebraska, Jon C. King, Terry Swope, Kevin Groeneweg, Pete Janzen, Mark A. Brogie

Nebraska Bird Review

The Townsend’s Warbler (Setophaga townsendi), Hermit Warbler (Setophaga occidentalis), Golden-cheeked Warbler (Setophaga chrysoparia), and Black-throated Green Warbler (Setophaga virens) are similar in appearance and vocalizations. Evaluation of mtDNA suggests that these four species diverged about 1 million years ago during the mid-Pleistocene (Lovette et al. 2010), at which time glaciation separated ancestral forms thus allowing for speciation (Morse and Poole 2020). Under the environmental conditions prevalent today, however, the breeding distribution of Townsend’s Warbler now overlaps to a limited extent with those of the Hermit and Black-throated Green Warblers, and hybridization occurs …

The Nebraska Bird Review, Volume 89 March 2021 Number 1

Nebraska Bird Review

Winter Field Report, Dec. 2020 - Feb. 2021, by W. Ross Silcock …2-17

2020-2021 Christmas Bird Counts …18, 29-40

Annual Color Photo Section …21-28

Apparent Townsend’s x Black-throated Green Warbler (Setophaga townsendi x virens) hybrids in Kansas and Nebraska, by Jon C. King, Terry Swope, Kevin Groeneweg, Pete Janzen, & Mark A. Brogie … 41

Annual Treasurer's Report for 2020, by Jan Johnson …46.

Subscription and Organization Information …47

Toxicity Of Sodium Nitrite-Based Vertebrate Pesticides For European Starlings (Sturnus Vulgaris), Scott J. Werner, Shelagh T. Deliberto, Hailey E. Mclean, Katherine E. Horak, Kirt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

In the 21st century, invasive animals rank second only to habitat destruction as the greatest threat to global biodiversity. Socially-acceptable and cost-effective strategies are needed to reduce the negative economic and environmental impacts of invasive animals. We investigated the potential for sodium nitrite (SN; CAS 7632-00-0) to serve as an avian toxicant for European starlings (Sturnus vulgaris L.). We also assessed the non-target hazard of an experimental formulation of SN that is being developed as a toxicant for invasive wild pigs (Sus scrofa L.). In gavage experiments with European starlings, we identified a lowest observed adverse effect level …

Sars-Cov-2 Exposure In Escaped Mink, Utah, Usa, Susan A. Shriner, Jeremy W. Ellis, J. Jeffrey Root, Annette Roug, Scott R. Stopak, Gerald W. Wiscomb, Jared R. Zierenberg, Hon S. Ip, Mia Kim Torchetti, Thomas J. Deliberto

United States Department of Agriculture Wildlife Services: Staff Publications

In August 2020, outbreaks of coronavirus disease were confirmed on mink farms in Utah, USA. We surveyed mammals captured on and around farms for evidence of infection or exposure. Free-ranging mink, presumed domestic escapees, exhibited high antibody titers, suggesting a potential severe acute respiratory syndrome coronavirus 2 transmission pathway to native wildlife.

We report a wildlife epidemiologic investigation of mammals captured on or near properties in Utah, USA, where outbreaks of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection occurred in farmed mink. Mink farms are relatively common in the United States, and most are small family farms. The US …

Great Expectations: Deconstructing The Process Pathways Underlying Beaver-Related Restoration, Caroline S. Nash, Gordon E. Grant, Susan Charnley, Jason B. Dunham, Hannah Gosnell, Mark B. Hausner, David S. Pilliod, Jimmy Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Beaver-related restoration is a process-based strategy that seeks to address wide-ranging ecological objectives by reestablishing dam building in degraded stream systems. Although the beaver-related restoration has broad appeal, especially in water-limited systems, its effectiveness is not yet well documented. In this article, we present a process-expectation framework that links beaver-related restoration tactics to commonly expected outcomes by identifying the set of process pathways that must occur to achieve those expected outcomes. We explore the contingency implicit within this framework using social and biophysical data from project and research sites. This analysis reveals that outcomes are often predicated on complex process …

Avian Visual Ecologists Should Consider Uv Absorbance And All Sensory Modalities: A Response To Wisenden Et Al. (2020), Sean T. O'Daniels, Scott J. Werner, Ken Yasukawa

United States Department of Agriculture Wildlife Services: Staff Publications

In a recent publication, Wisenden et al. (2020) examined responses of territorial male Red-winged Blackbirds (Agelaius phoeniceus) to models constructed with ultraviolet (UV)-reflective red epaulets for the purpose of determining if the addition of UV reflectance to epaulets ("UV+") changed the effectiveness of signals to receivers relative to "control" epaulets under field conditions. The authors hypothesized that "UV+epaulet coloration represents a visual signal with increased efficacy in territorial interactions." They presented behavioral data but no visual modeling data. Our aims in this commentary are to suggest alternative terms to those used by the authors, to express concern about the use …

Mosaic Agriculture: A Guide To Irrigated Crop And Forage Production In Northern Wa, Geoff A. Moore Mr, Clinton K. Revell Dr, Christopher Schelfhout Dr, Christopher Ham Mr, Samuel Crouch Mr, Meredith M. Guthrie

Bulletins 4000 -

The Bulletin is a comprehensive guide for pastoralists, agronomists, agribusiness and the broader community on the growing of irrigated crops and pastures within a rangeland pastoral setting.

Dispersed irrigation developments on stations throughout the northern rangelands (sometimes referred to as mosaic agriculture) has created opportunities for the introduction of more productive forage species and pastoralists can now grow high quality forage for 12 months of the year. This can help to overcome the key constraint of traditional pastoral systems, the low quality of the feed over the dry season that typically results in stock losing condition.

Phytogenic Water Additives Improve Broiler Growth Performance Via Modulation Of Intermediary Metabolism-Related Signaling Pathways, Joshua J. Flees, Nima K. Emami, Elizabeth Greene, Bhaskar Ganguly, Sami Dridi

Poultry Science Faculty Publications and Presentations

A ban on the use of antibiotic growth promoters (AGPs) has fueled and promoted scientific research towards the identification of reliable and effective alternatives. The supplementation of phytogenics AV/SSL12 (AVSSL) and Superliv Gold (SG) in water has been shown to improve broiler feed efficiency (FE) via modulation of hypothalamic neuropeptides. However, their effects on peripheral metabolic pathways are still unknown. The present study was undertaken to determine the effects of AVSSL and SG on lipid and protein metabolism-associated pathways in various tissues. Day-old male Cobb 500 chicks (n = 288) were randomly assigned to 3 treatment groups, with 8 …

Identification Of Snps Associated With Stress Response Traits Within High Stress And Low Stress Lines Of Japanese Quail, Steven Shumaker, Bhuwan Khatri, Stephanie Shouse, Dongwon Seo, Seong Kang, Wayne Kuenzel, Byungwhi C. Kong

Poultry Science Faculty Publications and Presentations

Mitigation of stress is of great importance in poultry production, as chronic stress can affect the efficiency of production traits. Selective breeding with a focus on stress responses can be used to combat the effects of stress. To better understand the genetic mechanisms driving differences in stress responses of a selectively bred population of Japanese quail, we performed genomic resequencing on 24 birds from High Stress (HS) and Low Stress (LS) lines of Japanese quail using Illumina HiSeq 2 × 150 bp paired end read technology in order to analyze Single Nucleotide Polymorphisms (SNPs) within the genome of each line. …

Development Of A Wild-Type Escherichia Coli Environmental Bloom Model To Evaluate Alternatives To Formaldehyde Fumigation In Broiler Chicken Hatch Cabinets, B. D. Graham, C. M. Selby, L. E. Graham, K. D. Teague, G. Tellez-Isaias, B. M. Hargis, C. N. Vuong

Poultry Science Faculty Publications and Presentations

Horizontal transmission of opportunistic Escherichia coli during hatch can have detrimental effects on early performance, particularly as pioneer colonizers. Commercially, formaldehyde is often applied in the United States to combat the bacterial bloom that occurs inside of the hatching environment. The purpose of these experiments was to develop a replicable E. coli horizontal challenge model to evaluate alternatives to formaldehyde sanitation applied to the hatching environment. In experiment 1, two trials were conducted for 2 wild-type (WT) E. coli isolates (isolate 1 [I1] or isolate 2 [I2]) to determine the appropriate in ovo challenge …

Research Note: Phytobiotics Modulate The Expression Profile Of Circulating Inflammasome And Cyto(Chemo)Kine In Whole Blood Of Broilers Exposed To Cyclic Heat Stress, Elizabeth S. Greene, Nima K. Emami, Sami Dridi

Poultry Science Faculty Publications and Presentations

Heat stress (HS) is a critical concern to the poultry industry as it affects both productivity and well-being. Various managerial and nutritional strategies have been proposed to mitigate the negative effects of HS in chickens, with plant-based additives showing promise. Recently, we reported the positive effect of a phytogenic feed additive (PFA) on growth performance in HS birds. Owing to the antioxidant nature of these compounds, we sought to further explore the effect of PFA on whole blood circulating chemokines, cytokines, and inflammasomes in HS broilers. Broilers (600 males, 1 d) were randomly assigned to 12 …

Effects Of Dietary Energy Levels On Performance And Carcass Yield Of 2 Meat-Type Broiler Lines Housed In Hot And Cool Ambient Temperatures, Pramir Maharjan, Katie M. Hilton, Garrett Mullenix, Jordan Weil, Antonio Beitia, Nawin Suesuttajit, Cole Umberson, Diego A. Martinez, Justina Caldas, Antonio Kalinowski, Nadia Yacoubi, Victor Naranjo, Judith A. England, Craig N. Coon

Poultry Science Faculty Publications and Presentations

Two meat-type broiler lines, line A and line B were fed experimental diets from 22-42 d with objectives to determine the effects of dietary metabolizable energy (ME) levels on feed intake (FI), performance, body composition, and processing yield as affected by environmental grow-out temperatures. Two thousand fifty male chicks from line A and 2,050 male chicks from line B were reared in 90-floor pens, 45 chicks per pen utilizing primary breeder nutrition and husbandry guidelines for starter (110 d) and grower (11-21 d) phases. Experimental finisher diets consisted of 5 increasing levels of apparent nitrogen corrected …

Phytogenic Feed Additives Improve Broiler Feed Efficiency Via Modulation Of Intermediary Lipid And Protein Metabolism-Related Signaling Pathways, Joshua J. Flees, Bhaskar Ganguly, Sami Dridi

Poultry Science Faculty Publications and Presentations

Diets enriched with phytogenic feed additives (PFA) such as AV/HGP/16 premix (AVHGP), Superliv concentrate premix (SCP), and bacteriostatic herbal growth promotor (BHGP) with essential oils have been shown to improve feed efficiency (FE) in broilers. This FE improvement was achieved via modulation of hypothalamic neuropeptides, which results despite feed intake reduction, in increased breast yield without changes in body weight compared to the control group. To gain further insights into the mode of action of these PFA, the present study aimed to determine the potential involvement of signaling pathways associated …

Coccidia Vaccine Challenge And Exogenous Enzyme Supplementation In Broiler Chicken 1. Effect On Digesta Viscosity, Diet Energy Utilization, And Apparent Metabolizable Energy Value Of Wheat, Andrew E. Dunaway, Sunday A. Adedokun

Animal and Food Sciences Faculty Publications

This study examined the effect of exogenous mixed-enzyme supplementation (xylanase, β-glucanase, and pectinase) to a corn-SBM (CS) and a wheat-CS-based (WCS) diet in birds challenged with coccidia vaccine (Coccivac B-52™). The WCS-based diet was produced by replacing 30% of the energy-yielding portions of the CS-based diet with wheat. On day 14, 448 (n = 7) Cobb by-product breeder male broilers were assigned to a 2 (diet types) × 2 (with or without enzyme supplementation) × 2 (0 or 20 × coccidia vaccine challenge; CVC) factorial arrangement of treatments in a completely randomized design for the determination of the apparent …

Estimating The Size Of Georgia's Resident Canada Goose Population, Gregory D. Balkcom

Georgia Journal of Science

Canada geese (Branta canadensis) are an important waterfowl species in Georgia, and are hunted across the state. To meet management objectives, managers need to understand the impacts of hunting regulations on the population of interest. Therefore, reliable population estimates are necessary. Population size can be estimated by various methods, including aerial surveys, ground surveys, or population indices such as the Lincoln Estimator. I used annual estimates of resident Canada goose harvest in Georgia from the U.S. Fish and Wildlife Service’s Harvest Information Program along with banding and recovery data from the Bird Banding Laboratory in a bias-adjusted version …

Factors Leading To Successful Island Rodent Eradications Following Initial Failure, Araceli Samaniego, Peter Kappes, Keith Broome, Steve Cranwell, Richard Griffiths, Grant Harper, Pete Mcclelland, Russell Palmer, Gerard Rocamora, Keith Springer, David Will, Shane Siers

United States Department of Agriculture Wildlife Services: Staff Publications

Island rodent eradications are increasingly conducted to eliminate the negative impacts of invasive rodents. The success rate in the tropics has been lower than in temperate regions, triggering research and reviews. Environmental factors unique to the tropics (e.g., land crabs and year-round rodent breeding) have been associated with eradication failure. Operational factors have also been important, but these have not been comprehensively assessed. The environmental and operational factors using global cases where rodent eradication initially failed and subsequent attempts occurred were compared. It was determined whether operational factors explained the initial failures, whether operational improvements explained subsequent successes, and whether …

Transcriptomic Profiling Of Fibropapillomatosis In Green Sea Turtles (Chelonia Mydas) From South Texas, Nicholas B. Blackburn, Ana C. Leandro, Nina Nahvi, Mariana A. Devlin, Marcelo Leandro, Ignacio Martinez Escobedo, Juan M. Peralta, Jeff George, Thomas W. Demaar, John Blangero, Megan Keniry, Joanne E. Curran

School of Medicine Publications

Sea turtle fibropapillomatosis (FP) is a tumor promoting disease that is one of several threats globally to endangered sea turtle populations. The prevalence of FP is highest in green sea turtle (Chelonia mydas) populations, and historically has shown considerable temporal growth. FP tumors can significantly affect the ability of turtles to forage for food and avoid predation and can grow to debilitating sizes. In the current study, based in South Texas, we have applied transcriptome sequencing to FP tumors and healthy control tissue to study the gene expression profiles of FP. By identifying differentially expressed turtle genes in …

Behavioral Analysis Of The Cryptoprocta Ferox In An Ex-Situ Condition, Emilie Alfonso

The Pegasus Review: UCF Undergraduate Research Journal

Fossas (Cryptoprocta ferox) are the top, endemic predators of Madagascar. Their populations are dwindling and are reported as “Vulnerable” by IUCN. In an effort to combat this, zoological facilities have placed the species on a captive breeding program. This study focuses on concerns one of those zoos had about their captive C. ferox. The purpose of this study was to collect activity budgets on the C. ferox to determine if there is a change in behavior due to construction occurring around the C. ferox’s habitat, analyze behavior changes during estrus, determine any behavior changes, as well …

Recent Advances In The Application Of Crispr/Cas9 Gene Editing System In Poultry Species, Collins N. Khwatenge, Samuel N. Nahashon

Agricultural and Environmental Sciences Faculty Research

CRISPR/Cas9 system genome editing is revolutionizing genetics research in a wide spectrum of animal models in the genetic era. Among these animals, is the poultry species. CRISPR technology is the newest and most advanced gene-editing tool that allows researchers to modify and alter gene functions for transcriptional regulation, gene targeting, epigenetic modification, gene therapy, and drug delivery in the animal genome. The applicability of the CRISPR/Cas9 system in gene editing and modification of genomes in the avian species is still emerging. Up to date, substantial progress in using CRISPR/Cas9 technology has been made in only two poultry species (chicken and …

Sensitivity Of Wild-Type And Rifampicin-Resistant O157 And Non-O157 Shiga Toxin-Producing Escherichia Coli To Elevated Hydrostatic Pressure And Lactic Acid In Ground Meat And Meat Homogenate, Abimbola Allison, Aliyar Cyrus Fouladkhah

Agricultural and Environmental Sciences Faculty Research

Various serogroups of Shiga toxin-producing Escherichia coli have been epidemiologically associated with foodborne disease episodes in the United States and around the globe, with E. coli O157: H7 as the dominant serogroup of public health concern. Serogroups other than O157 are currently associated with about 60% of Shiga toxin-producing E. coli related foodborne illness episodes. Current study evaluated sensitivity of the O157 and epidemiologically important non-O157 serogroups of the pathogen to elevated hydrostatic pressure and 1% lactic acid. Pressure intensity of 250 to 650 MPa were applied for 0 to 7 min for inactivation of strain mixtures of …

Occurrence Of Ticks (Acari: Ixodidae) On Birds In Northwestern Lower Michigan, 2011-2019, William C. Scharf, Lisa Aukland, Gary W. Shugart, Sarah A. Hamer

The Great Lakes Entomologist

Abstract

Monitoring tick infestation of wildlife provides baseline tick

occurrence data that may have human or animal health implications. We collected 312 ticks of four species from 5,122 birds of 93 species while monitoring bird migration during 15 fall and spring seasons between 2011 and 2019 in the northern Lower Peninsula of Michigan. Twenty-seven of 93 bird species hosted ticks with an overall prevalence (=at least one tick) of 3.6% (185/5,122). Median burden was one tick/per infested bird with a range of 1-16 ticks per infested bird. Tick species collected were primarily Haemaphysalis leporispalustris (Packard) and Ixodes scapularis Say, with …

Observational Study Of Two Ex Situ North American River Otters (Lontra Canadensis), Julia Rifenberg

The Pegasus Review: UCF Undergraduate Research Journal

Zoos enable the ability to study how captive conditions impact the behaviors of animals. In this study, I observed two North American river otters housed at the Central Florida Zoo to evaluate behavioral changes after the male had been removed from the female for a month-long medical examination. The aim of this study was to 1) determine if mating behaviors were still occurring between the two river otters following the male’s removal and 2) to assess the welfare of the male and female river otters in captivity by observing their interactions and individual behaviors. Observed behaviors were compared to documented …

Generation Of A Biobank From Two Adult Thoroughbred Stallions For The Functional Annotation Of Animal Genomes Initiative, Callum G. Donnelly, Rebecca R. Bellone, Erin N. Hales, Annee Nguyen, Scott A. Katzman, Ghislaine A. Dujovne, Kelly E. Knickelbein, Felipe Avila, Ted S. Kalbfleisch, Elena Giulotto, Nicole B. Kingsley, Jocelyn Tanaka, Elizabeth Esdaile, Sichong Peng, Anna Dahlgren, Anna Fuller, Michael J. Mienaltowski, Terje Raudsepp, Verena K. Affolter, Jessica L. Petersen, Carrie J. Finno

Department of Animal Science: Faculty Publications

Following the successful creation of a biobank from two adult Thoroughbred mares, this study aimed to recapitulate sample collection in two adult Thoroughbred stallions as part of the Functional Annotation of the Animal Genome (FAANG) initiative. Both stallions underwent thorough physical, lameness, neurologic, and ophthalmic (including electroretinography) examinations prior to humane euthanasia. Epididymal sperm was recovered from both stallions immediately postmortem and cryopreserved. Aseptically collected full thickness skin biopsies were used to isolate, culture and cryopreserve dermal fibroblasts. Serum, plasma, cerebrospinal fluid, urine, and gastrointestinal content from various locations were collected and cryopreserved. Under guidance of a board-certified veterinary anatomic …

Anthropogenic And Climatic Factors Interact To Influence Reproductive Timing And Effort, Susannah S. French, Geoffrey Smith

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Reproduction, although absolutely essential to a species’ persistence, is in itself challenging. As anthropogenic change increasingly affects every landscape on Earth, it is critical to understand how specific pressures impact the reproductive efforts of individuals, which directly contribute to the success or failure of populations. However, organisms rarely encounter a single burden at a time, and the interactions of environmental challenges can have compounding effects. Disentangling environmental and physiological pressures is difficult because they are often context-dependent and not generalizable, but long-term monitoring across variable landscapes and weather patterns can improve our understanding of these complex interactions. We tested the …

Habitat Characteristics Of Two Scorpion Species, Liocheles Australasiae (Fabricius, 1775) And Isometrus Maculatus (De Geer, 1778) In Miyako Islands, Japan, Kazusa Kawai

Euscorpius

Scorpion surveys were conducted in the five islands: Miyakojima, Ikemajima, Kurimajima, Irabujima, and Shimojishima (Miyako Islands, part of Nansei/Ryukyu Islands of Japan). Eight individuals of Liocheles australasiae (Hormuridae) and 16 individuals of Isometrus maculatus (Buthidae) were observed in a total of 10 points on four islands, except Ikemajima. The localities of both species are recorded in this survey, focusing on altitude, distance from the nearest coast, and sunlight. The lowest temperatures in the habitat are also examined, and the cold tolerance of the species is discussed.

Noise Distracts Foraging Bats, Louise C. Allen, Nickolay I. Hristov, Juliette J. Rubin, Joseph T. Lightsey, Jesse R. Barber

Biology Faculty Publications and Presentations

Predators frequently must detect and localize their prey in challenging environments. Noisy environments have been prevalent across the evolutionary history of predator–prey relationships, but now with increasing anthropogenic activities noise is becoming a more prominent feature of many landscapes. Here, we use the gleaning pallid bat, Antrozous pallidus, to investigate the mechanism by which noise disrupts hunting behaviour. Noise can primarily function to mask—obscure by spectrally overlapping a cue of interest, or distract—occupy an animal's attentional or other cognitive resources. Using band-limited white noise treatments that either overlapped the frequencies of a prey cue or did not …

Observations On The Distribution And Status Of Selected Nebraska Mammals, Zachary P. Roehrs, Russell A. Benedict, Thomas E. Labedz, Hugh H. Genoways

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Information on the distribution and current status of 25 species or subspecies of mammals occurring in Nebraska are presented. The species covered include one shrew, an armadillo, eight bats, 10 rodents (including two subspecies of one species), three carnivores, and one artiodactyl. Distributional information reported includes the first state record for one species (Sorex nanus) and new county records for 18 species. In Nebraska, we know that mammals are shifting their geographic ranges with some extending populations into the state, whereas others are expanding their geographic ranges within the state. The current status of six additional mammalian taxa …

Evaluating Accuracy Of Dna Pool Construction Based On White Blood Cell Counts, Amy N. Abrams, T. G. Mcdaneld, John W. Keele, Carol G. Chitko-Mckown, Larry A. Kuehn, Michael G. Gonda

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Pooling individual samples prior to DNA extraction can mitigate the cost of DNA extraction and genotyping; however, these methods need to accurately generate equal representation of individuals within pools. The objective of this study was to determine accuracy of pool construction of blood samples based on white blood cell counts compared to two common DNA quantification methods. Fifty individual bovine blood samples were collected, and then pooled with all individuals represented in each pool. Pools were constructed with the target of equal representation of each individual animal based on number of white blood cells, spectrophotometric readings, spectrofluorometric readings, and whole …

Data From: Recovery From Discrete Wound Severities In Side-Blotched Lizards (Uta Stansburiana): Implications For Energy Budget, Locomotor Performance, And Oxidative Stress, Susannah S. French, Spencer B. Hudson

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Wounding events (predation attempts, competitive combat) result in injuries and/or infections that induce integrated immune responses for the recovery process. Despite the survival benefits of immunity in this context, the costs incurred may require investment to be diverted from traits contributing to immediate and/or future survival, such as locomotor performance and oxidative status. Yet, whether trait constraints manifest likely depends on wound severity and the implications for energy budget. For this study, food intake, body mass, sprint speed, and oxidative indices (reactive oxygen metabolites, antioxidant capacity) were monitored in male side-blotched lizards (Uta stansburiana) healing from cutaneous wounds of discrete …

Rapid Estimation Of Salmonella Enterica Contamination Level In Ground Beef – Application Of The Time-To-Positivity Method Using A Combination Of Molecular Detection And Direct Plating, Dayna M. Harhay, Margaret D. Weinroth, James L. Bono, Gregory P. Harhay, Joseph M. Bosilevac

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Little progress has been made in decreasing the incidence rate of salmonellosis in the US over the past decade. Mitigating the contribution of contaminated raw meat to the salmonellosis incidence rate requires rapid methods for quantifying Salmonella, so that highly contaminated products can be removed before entering the food chain. Here we evaluated the use of Time-to-Positivity (TTP) as a rapid, semi-quantitative approach for estimating Salmonella contamination levels in ground beef. Growth rates of 14 Salmonella strains (inoculated at log 1 to −2 CFU/g) were characterized in lean ground beef mTSB enrichments and time-to-detection was determined using culture and molecular …