Specificity and sensitivity evaluation of novel and existing Bacteroidales and Bifidobacteria-specific PCR assays on feces and sewage samples and their application for microbial source tracking in Ireland

Three novel ruminant-specific PCR assays, an existing ruminant-specific PCR assay and five existing human-specific PCR assays, which target 16S rDNA from Bacteroidales or Bifidobacteria, were evaluated. The assays were tested on DNA extracted from ruminant (n = 74), human (n = 59) and non-ruminant animal (n = 44) sewage/fecal samples collected in Ireland. The three novel PCR assays compared favourably to the existing ruminant-specific assay, exhibiting sensitivities of 91 - 100% and specificities of 95 - 100% as compared to a sensitivity of 95% and specificity of 94%, for the existing ruminant-specific assay. Of the five human-specific PCR assays, the assay targeting the Bifidobacterium catenulatum group was the most promising, exhibiting a sensitivity of 100% (with human sewage samples) and a specificity of 87%. When tested on rural water samples that were naturally contaminated by ruminant feces, the three novel PCR assays tested positive with a much greater percentage (52 - 87%) of samples than the existing ruminant-specific assay (17%). These novel ruminant-specific assays show promise for microbial source tracking and merit further field testing and specificity evaluation.ERTD

Northern Great Plains Beef Production: Production and Marketing Practices of Cow-Calf Producers

Ruminant livestock production in North Dakota, South Dakota, Montana, and Wyoming is critical to the region's economy. Because of the economic significance of ruminant livestock production, producers in the four-state area are continually looking for opportunities to increase income and improve the viability of their farm and ranch operation. Accordingly, the Four-state Ruminant Consortium, an integrated research and extension program, was created to specifically address issues related to ruminant livestock production. One of the more widely applicable possibilities for adding value through the regions's ruminant livestock sector appears to be backgrounding feeder calves. However, while economic analysis has indicated that stockgrowers in the study area could typically increase their net returns by backgrounding feeder calves, anecdotal evidence suggests relatively few producers are presently backgrounding feeder calves. To identify the socioeconomic impediments inhibiting producers from backgrounding feeder cattle, this study sought to identify managerial, social, and institutional factors that influence and perhaps constrain producers' ability or willingness to background feeder cattle. Study objectives were to identify and document producers' current production and marketing practices as well as identify stock growers' perception of opportunities for and impediments to expansion of the ruminant livestock industry in the study area. A mail questionnaire was delivered to 5,270 livestock producers in 37 counties in the 4-state study area of southwestern North Dakota, northwestern South Dakota, southwestern Montana and northwestern Wyoming. The questionnaire was designed to solicit a wide variety of information about operators' current production practices, including marketing, backgrounding, retained ownership, herd management, and feed and forage practices. The questionnaire also solicited operators attitudes on a wide variety of issues related to opportunities for and impediments to the expansion of the ruminant livestock industry in the study area as well asking respondents to identify what types of information would be of most interest to them and in what form they would prefer that information be delivered. The questionnaire also collected basic demographic data. Findings from the mail questionnaire are detailed in this report.Backgrounding, Feeder calves, Beef cattle producer characteristics, Feeder cattle production practices, Beef cattle marketing, Livestock Production/Industries, Marketing,

Identification of Host-Specific Bacteroidales 16S rDNA Sequences from Human Sewage and Ruminant Feces

The need to identify the source of fecal contamination of water has led to the development of various fecal source identification methods, a field known as microbial source tracking (MST). One promising method of MST focuses on fecal members of the order Bacteroidales, some of which exhibit a high degree of host-specificity. In order to identify host-specific Bacteroidales genetic markers, a ∼1060 bp section of Bacteroidales 16S rDNA was amplified from human sewage (n = 6), and bovine (n = 6) and ovine fecal (n = 5) samples and used for the generation of three clone libraries. Phylogenetic analysis of sequences from the three clone libraries revealed that the Bacteroidales species found in both human sewage and bovine and ovine feces were a highly diverse group of organisms, many of which were not represented by previously characterised 16S rDNA. Ovine and bovine feces appear to host similar populations of Bacteroidales species and these species were more diverse and less closely related to cultivated species than the Bacteroidales population found in human sewage. Species of Bacteroidales from the ruminant and human feces formed isolated clusters containing putatively host-specific sequences. These sequences were subsequently exploited for the design of host-specific primers which were used in MST studies

Productivity Growth and Convergence in Crop, Ruminant and Non-Ruminant Production: Measurement and Forecasts

There is considerable interest in projections of future productivity growth in agriculture. Whether one is interested in the outlook for global commodity markets, future patterns of international trade, or the interactions between land use, deforestation and ecological diversity, the rate of productivity growth in agriculture is an essential input. Yet solid projections for this variable have proven elusive particularly on a global basis. This is due, in no small part, to the difficulty in measuring historical productivity growth. The purpose of this paper is to report the latest time series evidence on total factor productivity growth for crops, ruminants and non-ruminant livestock, on a global basis. We then follow with tests for convergence amongst regions, providing forecasts for farm productivity growth to the year 2040. The results suggest that most regions in the sample are likely to experience larger productivity gains in livestock than in crops. Within livestock, the non-ruminant sector is expected to continue to be more dynamic than the ruminant sector. Given the rapid rates of productivity growth observed recently, non-ruminant and crop productivity in developing countries may be converging to the productivity levels of developed countries. For ruminants, the results show that productivity levels may be diverging between developed and developing countries.Malmquist index, productivity, convergence, projections, crops, livestock, Productivity Analysis, D24, O13, O47, Q10,