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Saudi student enrollment in U.S. colleges and universities has nearly tripled since 2009-2010, in large part due to the King Abdullah Scholarship Program. The representation of Saudi females is also increasing due to the loosening of Saudi Arabia’s long-standing restrictions on women’s travel and acceptable fields of study and careers. This constructivist study highlights some of the academic experiences of female Saudi graduate students at a Comprehensive Doctoral University in the western United States. Challenges related to students’ insufficient English language skills, differences in their comfort levels interacting with American and Saudi men, positive relationships with both male and female faculty members, and generally positive feelings about their experiences at their university of choice emerged as themes within the data. The participants’ varied prior experiences with mixed-gendered educational environments led to differing levels of comfort with developing relationships with men. [ABSTRACT FROM AUTHOR]

The article summarizes findings from the investigations conducted on the outbreaks of Escherichia coli O157:H7 infections in North Carolina, Florida and Arizona from 2004-2005, which indicated the need for adequate control measures to reduce zoonotic transmission of the infection. The outbreak in North Carolina was said to have originated from a petting zoo at the North Carolina State Fair. There were reports of hemolytic uremic syndrome from children who visited the petting zoo and cases of diarrheal illnesses.

Salmonella is one of the most serious foodborne pathogenic bacteria in the United States, causing an estimated 1.3 million human illnesses each year. Dairy cows can be reservoirs of foodborne pathogenic bacteria, including Salmonella spp.; it is estimated that from 27 to 31% of dairy herds across the United States are colonized by Salmonella. The present study was designed to examine the occurrence of Salmonella spp. on dairies and to examine the serotypic diversity of Salmonella isolates on sampled dairies from across the United States. Fecal samples (n = 60 per dairy) were collected from 4 dairies in each of 4 states for a total of 960 fecal samples representing a total population of 13,200 dairy cattle. In the present study, 93 of 960 samples (9.96%) collected were culture-positive for Salmonella enterica. At least one Salmonella fecal-shedding cow was found in 9 of the 16 herds (56%) and the within-herd prevalence varied in our study from 0% in 7 herds to a maximum of 37% in 2 herds, with a mean prevalence among Salmonella-positive herds of 17%. Seventeen different serotypes were isolated, representing 7 different Salmonella serogroups. There were 2 or more different serogroups and serotypes present on 7 of the 9 Salmonella-positive farms. Serotypes Montevideo and Muenster were the most frequent and widespread. From our data, it appears that subclinical colonization with Salmonella enterica is relatively common on dairy farms and is represented by diverse serotypes on US dairy farms. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7, Salmonella, and Listeria are foodborne pathogens of critical importance that often colonize cattle. E. coli O157:H7 can be specifically killed by lytic bacteriophage, and lytic bacteriophage treatment has been suggested as a pre-harvest intervention strategy to reduce foodborne pathogens in cattle. To date, no systematic approach to determine the incidence of E. coli O157:H7-infecting lytic bacteriophage has been published. Therefore, the current study was designed to determine (1) the incidence of E. coli O157, Salmonella spp., and Listeria and (2) the incidence of E. coli O157:H7-infecting bacteriophage in the feces of feedlot steers in commercial feedlots in the United States. Fecal samples (n=60) were collected from four feedlots in two Southern Great Plains states (total (n=240 fecal samples). Salmonella and E. coli O157:H7 were found in 3.8% and 11.7% of the fecal samples, respectively. Bacteriophage targeting E. coli O157:H7 were found in all four feedlots, in 15% of the individual fecal samples, and in 55% of the cattle pens. Our results indicate that such bacteriophage are widespread in feedlot cattle, suggesting that further research into the ecological role of bacteriophage in the gastrointestinal tract is needed.

The aim of the present study was twofold: first, to design a panel of 96 sires that reflects the breadth of genetic diversity in U.S. beef cattle, and second, to use this panel to discover nucleotide sequence diversity and haplotype structures of interleukin (IL)-8 in commercial populations. The latter is a requisite for epidemiological studies designed to test whether IL8 alleles are risk factors for acquiring or maintaining bacterial infections in production environments. IL-8 encodes a proinflammatory cytokine that plays a central role in cell-mediated immunity by attracting and activating neutrophils in the early stages of host defense against bacterial invasion. Seven single-nucleotide polymorphism (SNP) markers were identified by sequencing two IL8 DNA segments amplified from the panel of 17 popular cattle breeds (MARC beef cattle diversity panel, version 2.1). Assays for automated genotype scoring by matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF MS) were developed to independently verify the seven SNP alleles in the 96 bulls and 313 cattle from the MARC reference population. Five haplotype structures, spanning the two IL8 DNA segments, were unambiguously defined for the set of seven IL8 SNPs. Based on the breadth of germplasm in bovine diversity panel, the five haplotype structures for IL8 are estimated to represent >98% of those present in these DNA segments in commercial populations of U.S. beef cattle. The frequencies of the five respective haplotypes in the eight Angus sires of the diversity panel (0.75, 0.25, 0.00, 0.00. 0.00) were similar to those scored in 150 purebred Angus cattle from six herds in four Midwestern states (0.82, 0.18, 0.01, 0.00 0.00), suggesting that the diversity panel may also be useful for estimating allele frequencies in commercial populations.

The prevalence of and risk factors for ovine lentivirus (OLV) infection in 1466 breeding ewes in nine US Meat Animal Research Center (MARC) flocks were determined using a recombinant transmembrane protein (PTM) enzyme-linked immunosorbent assay (ELISA) to detect serum anti-OLV antibodies and define infection. Based on multivariable logistic regression, confinement birth and rearing (odds ratio (OR) = 1.6), older weaning ages (OR = 1.1 week-1), and older age (OR = 1.3-2.5 year-1 beyond age 1 year) were significantly associated with higher OLV prevalence in ewes. Prevalence also varied significantly by flock, with Finnsheep and Texel ewes having the highest prevalences and Booroola Merino and Suffolk ewes having the lowest prevalences. These findings support the hypothesis that management control efforts should concentrate on events early in the life of sheep, as this period is associated with factors which can modulate the risk for OLV infection.

We used a previously described sensitive and specific ovine lentivirus (OLV) recombinant transmembrane (rTM) protein enzyme-linked immunosorbent assay (ELISA) to detect anti-OLV antibodies and define OLV infection in breeding ewes from nine US Meat Animal Research Center (MARC) flocks. We estimated the production impacts of dam rTM ELISA seropositivity on ewe and lamb productivity in the birth-to-weaning interval using production data from 1466 breeding ewes (of which 1242 actually lambed) and their 2452 lambs born in spring 1992 using several multiple linear and logistic regression models. By adjusting for lamb weaning age, gender, type of birth and rearing, birth difficulty, dam age, and flock, the component of ewe or lamb productivity related to ewe OLV infection alone was isolated. The rTM ELISA-negative ewes produced significantly more total weight of weaned lamb per ewe-lambing (3.84 kg) and per ewe ram-exposed (4.95 kg) compared to their OLV-positive flockmates. Negative ewes also weaned 0.11 more lambs per ewe-lambing and 0.09 more lambs per ewe ram-exposed, gave birth to 0.13 more lambs per ewe ram-exposed, and were more likely to lamb after breeding (odds ratio (OR) = 1.9) compared to equivalent OLV-positive ewes. Lambs reared by OLV-negative ewes weighed 0.15 kg more at birth, gained 8 g more per day through weaning, and weighed 0.59 kg more at 56-day weaning. Preweaning mortality was lower (OR = 0.8) among lambs born to OLV-negative compared to OLV-positive ewes, although this difference was not significant. Our results suggest that subclinical OLV infection has important detrimental effects on sheep production which occur in cumulative fashion from breeding through weaning and that OLV control efforts may be financially justified in some sheep flocks.