Research in Veterinary Medical Science

It is my objective to discuss briefly some of the factors that are important to productive research in veterinary medical science. This discussion is directed primarily to those who now are entering research, and those still contemplating the wisdom of their decision to enter research. It also is designed to help the beginning researcher determine his strengths and weaknesses in the field of scientific investigation and to provide a guide in preparing for a research career. I will not get into the philosophical aspects of re-research, but confine myself to the superficial what is involved aspect

Molecular evidence for sediment nitrogen fixation in a temperate New England estuary

Primary production in coastal waters is generally nitrogen (N) limited with denitrification outpacing nitrogen fixation (N2-fixation). However, recent work suggests that we have potentially underestimated the importance of heterotrophic sediment N2-fixation in marine ecosystems. We used clone libraries to examine transcript diversity of nifH (a gene associated with N2-fixation) in sediments at three sites in a temperate New England estuary (Waquoit Bay, Massachusetts, USA) and compared our results to net sediment N2 fluxes previously measured at these sites. We observed nifH expression at all sites, including a site heavily impacted by anthropogenic N. At this N impacted site, we also observed mean net sediment N2-fixation, linking the geochemical rate measurement with nifH expression. This same site also had the lowest diversity (non-parametric Shannon = 2.75). At the two other sites, we also detected nifH transcripts, however, the mean N2 flux indicated net denitrification. These results suggest that N2-fixation and denitrification co-occur in these sediments. Of the unique sequences in this study, 67% were most closely related to uncultured bacteria from various marine environments, 17% to Cluster III, 15% to Cluster I, and only 1% to Cluster II. These data add to the growing body of literature that sediment heterotrophic N2-fixation, even under high inorganic nitrogen concentrations, may be an important yet overlooked source of N in coastal systems

Undetermined and accidental mortality rates as possible sources of underreported suicides: population-based study comparing Islamic countries and traditionally religious Western countries.

BACKGROUND: Four Western countries (Greece, Ireland, Italy and Portugal) with strong Orthodox and Catholic traditions have been associated with the underreporting of death by suicide, and underreported suicides are sometimes found among deaths recorded as 'undetermined' or 'accidental'. AIMS: This population-based study tests whether there are any significant difference in patterns of suicides, undetermined deaths and accidental deaths between these four Western countries and 21 predominately Islamic countries. METHOD: World Health Organization age-standardised death rates per million population were used to compare suicide rates with combined undetermined death and accidental death (UnD+AccD) rates, from which odds ratios were calculated. Substantial odds ratios (OR > 2.0) were taken as indicative of likely underreporting of suicides. The Islamic countries come from four different historico-cultural regions, described as: less-traditional Islamic countries; former USSR countries; Gulf Arab states; and Middle Eastern and North African countries. χ2-tests were used to determine any significant differences between the Western comparator countries and the Islamic regions. RESULTS: For the Western comparator countries, the average suicide rate was 66 per million population, the average undetermined death rate 56 per million and the average accidental death rate 58 per million, yielding a suicide:UnD+AccD odds ratio (OR) of 1.73. The average values for the other three groups were as follows. Less-traditional Islamic countries: suicide rate, 31 per million; UnD+AccD rate, 101 per million; suicide:UnD+AccD OR = 3.3. Former USSR countries: suicide rate, 61 per million; UnD+AccD rate, 221 per million; suicide:UnD+AccD OR = 3.6. Gulf Arab states: suicide rate, 10 per million; UnD+AccD rate, 76 per million; suicide:UnD+AccD OR = 8.6. Middle Eastern and North African countries: suicide rate, 6 per million; UnD+AccD rate, 151 per million; suicide:UnD+AccD OR = 25.2. The patterns of these mortalities in the Islamic countries was significantly different from Western comparator countries. CONCLUSIONS: The results indicate underreporting of suicides in Islamic countries. This might inadvertently lead to reduced access to mental health preventive services in both Western and Islamic countries

Effects of Limit Feeding a High Concentrate Diet on Feedlot Performance and Carcass Composition of Lambs

Limit feeding high concentrate diets offers several potential benefits to lamb feeders. Limit feeding is one alternative to ad libitum feeding where intake is restricted to an amount which will permit animals to attain some predetermined daily weight gain. This type of feeding system provides a means to reduce day-to-day variations in feed intake, simplifies bunk management, and allows for greater control over feed inventories (Zinn, 1 986) . Using limit feeding to program a particular rate of gain also allows greater marketing flexibility. Restricting intake has been shown to improve the efficiency at which feed is converted into live weight gain in sheep (Glimp et al. , 1989) and cattle (Plegge, 1986) . Reduced average daily gains have been shown to reduce the fat content of empty body weight gains (Turgeon et al. , 1986) . The objectives of this study were to determine the effect of limit feeding a high concentrate diet to achieve three different rates of gain on feedlot performance and body composition of growing lambs

Evaluating the Agronomic Feasibility of Planting late Season Corn for Feedlot Cattle

Yield, Ib/acre, bushel weight (BD), Ib/bu, relative maturity (RELMAT), chemical composition and in vitro dry matter digestibility (IVDMD) were used to screen corn varieties In = 20) of varying maturities grown under the stress of a shortened growing season. Corn varieties were planted in late June of 1996. Whole shell corn (WSC) and ear corn (EC) were harvested. Bushel weight was quantified on WSC. Yields for WSC, and EC were 1941 + 706 and 2307 ± 997 Ib DM/acre, respectively. Whole shell corn and EC were sorted into yield (YGP) groups. Whole shell corn yields were 2942 ± 248, 2305 ± 138, and 1292 ± 343 Ib DM/acre for YGPI through YGP3, respectively. The EC yields were 3740 ± 207, 2980 ± 208, 1897 ± 235 and 1139 ± 455 Ib DM1 acre for YGP 1 through 4, respectively. For WSC, YGP 1, YGP 2 and YGP 3 produced 2529, 1956 and 1099 Ib TDN/ac, respectively. Ear corn YGP 1, YGP 2, YGP 3 and YGP 4 produced 2980, 2180, 1437 and 780 Ib of TDN/ac, respectively. Increased yield in corn varieties grown under the stress of a shortened growing season was attributed to an increase in starch content. Even so, digestibility and energy content were not related (P \u3e .05) to yield or BD. Relative maturity did not influence (P \u3e .05) chemical composition, digestibility or energy content. Results suggest that while selecting earlier maturing corn for short growing seasons improves yields, it gives no advantage to feed value. Bushel weight, yield or maturity date should not be used as single criteria when predicting feed value of corn grown under the stress of a shortened growing season

Neutrinos and Future Concordance Cosmologies

We review the free parameters in the concordance cosmology, and those which might be added to this set as the quality of astrophysical data improves. Most concordance parameters encode information about otherwise unexplored aspects of high energy physics, up to the GUT scale via the "inflationary sector," and possibly even the Planck scale in the case of dark energy. We explain how neutrino properties may be constrained by future astrophysical measurements. Conversely, future neutrino physics experiments which directly measure these parameters will remove uncertainty from fits to astrophysical data, and improve our ability to determine the global properties of our universe.Comment: Proceedings of paper given at Neutrino 2008 meeting (by RE