Jason E. Lombard

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The objectives of this study were to determine incidence of stillbirths and heifer-calf morbidity and mortality, and their association with dystocia on 3 Colorado dairies. A total of 7,380 calvings produced 7,788 calves on 3 Colorado dairy operations between October 1, 2001, and November 5, 2002. Dystocia score and calf status (alive vs. dead) were recorded(More)
Failure of passive transfer of immunity (FPT) in dairy replacement calves has been linked to increased neonatal morbidity and mortality and long-term decreases in productivity. The purpose of this study was to estimate the prevalence of FPT in US dairy heifer calves in 2007 and to use nationally representative data to investigate associations of FPT with(More)
OBJECTIVE To determine effects on production and risk of removal related to Mycobacterium avium subsp paratuberculosis (MAP) infection at the individual animal level in dairy cattle. DESIGN Longitudinal study. ANIMALS 7,879 dairy cows from 38 herds in 16 states. PROCEDURE A subset of dairy cattle operations that participated in the National Animal(More)
AIMS To estimate prevalence and antimicrobial susceptibility of enterococci in faeces collected in 2007 from U.S. dairy cattle. METHODS AND RESULTS A total of 718 faecal samples from 122 dairy cattle operations from 17 US States were collected and cultured for the presence of enterococci. One hundred and eighteen of the 122 operations (96·7%) had at least(More)
Mycobacterium avium subspecies paratuberculosis (MAP) disseminated infection in dairy cattle affects animal health and productivity and is also a potential public health concern. The study objectives were to characterize MAP disseminated infection in dairy cattle and to determine the role of antemortem tests in detecting cattle with disseminated infection.(More)
Johne’s disease is the clinical manifestation of Mycobacterium avium subsp. paratuberculosis (MAP) infection and has become widespread since it was first observed in the United States in the early 1900s. MAP is primarily spread through the fecal-oral route, and herds generally become infected by unknowingly purchasing infected animals. The economic losses(More)
The objective of this study was to evaluate the effect of intramuscular (i.m.) ceftiofur (2.2 mg/kg) on important outcomes of systemically mild clinical mastitis episodes in lactating dairy cattle. Cows with clinical mastitis were randomly assigned to a treatment group: pirlimycin intramammary (i.m.m.) (n = 35), pirlimycin i.m.m. and ceftiofur i.m.m. (n =(More)
The objectives of this study were to determine the distribution of Mycobacterium avium subspecies paratuberculosis (MAP) in the environment and assess the relationship between the culture status of MAP in the farm environment and herd infection status. The National Animal Health Monitoring System's Dairy 2002 study surveyed dairy operations in 21 states.(More)
The zoonotic bacteria Salmonella enterica, Listeria monocytogenes, and Escherichia coli are known to infect dairy cows while not always causing clinical signs of disease. These pathogens are sometimes found in raw milk, and human disease outbreaks due to these organisms have been associated with the consumption of raw milk or raw milk products. Bulk tank(More)
Dairy cow mortality is an increasingly severe problem for the US dairy industry. The objective of this study was to examine a variety of herd management practices and herd characteristics to identify factors associated with increased cow mortality in US dairy herds. The National Animal Health Monitoring System's Dairy 2002 study surveyed dairy operations in(More)