Rapid Detection of Avian Eimeria Species Using Denaturing Gradient Gel Electrophoresis

A denaturing gradient gel electrophoresis (DGGE) assay was developed to rapidly discriminate species of avian Eimeria. Amplification by PCR of the small subunit ribosomal RNA gene (approximately 1,600 nucleotides) with Eimeria genus-specific primers followed by cloning and sequencing allowed us to carry out phylogenetic analyses and identify clone sequences to species level in most cases. Clones were subsequently used to amplify a smaller fragment (approximately 120 nucleotides) suitable for DGGE. The fragments were separated on denaturing gradient gel and bands with unique migration distances were mixed to obtain an identification ladder. The identification ladder and PCR products obtained from DNA extracted from fecal samples from several poultry farms were compared. Applying the DGGE method in this study allowed a rapid differentiation of Eimeria species present in fecal samples collected from poultry farms

Non-conventional Technologies as Alternative Solutions to the Proposed Whakamaru-Otahuhu Transmission Upgrade

This commentary brings together a preliminary view of the potential of non-conventional generation as a comprehensive alternative solution to the proposed Auckland transmission upgrade

Excitatory Action of Extracellular ATP on Chick Skeletal Muscle

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74927/1/j.1749-6632.1990.tb37713.x.pd

A calcium‐ and voltage‐dependent chloride current in developing chick skeletal muscle.

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109959/1/tjp19894171241.pd

Evolutionary adaptations of ruminants and their potential relevance for modern production systems

Comparative physiology applies methods established in domestic animal science to a wider variety of species. This can lead to improved insight into evolutionary adaptations of domestic animals, by putting domestic species into a broader context. Examples include the variety of responses to seasonally fluctuating environments, different adaptations to heat and drought, and in particular adaptations to herbivory and various herbivore niches. Herbivores generally face the challenge that a high food intake compromises digestive efficiency (by reducing ingesta retention time and time available for selective feeding and for food comminution), and a variety of digestive strategies have evolved in response. Ruminants are very successful herbivores. They benefit from potential advantages of a forestomach without being constrained in their food intake as much as other foregut fermenters, because of their peculiar reticuloruminal sorting mechanism that retains food requiring further digestion but clears the forestomach of already digested material; the same mechanism also optimises food comminution. Wild ruminants vary widely in the degree to which their rumen contents ‘stratify', with little stratification in ‘moose-type' ruminants (which are mostly restricted to a browse niche) and a high degree of stratification into gas, particle and fluid layers in ‘cattle-type' ruminants (which are more flexible as intermediate feeders and grazers). Yet all ruminants uniformly achieve efficient selective particle retention, suggesting that functions other than particle retention played an important role in the evolution of stratification-enhancing adaptations. One interesting emerging hypothesis is that the high fluid turnover observed in ‘cattle-type' ruminants - which is a prerequisite for stratification - is an adaptation that not only leads to a shift of the sorting mechanism from the reticulum to the whole reticulo-rumen, but also optimises the harvest of microbial protein from the forestomach. Although potential benefits of this adaptation have not been quantified, the evidence for convergent evolution toward stratification suggests that they must be substantial. In modern production systems, the main way in which humans influence the efficiency of energy uptake is by manipulating diet quality. Selective breeding for conversion efficiency has resulted in notable differences between wild and domestic animals. With increased knowledge on the relevance of individual factors, that is fluid throughput through the reticulo-rumen, more specific selection parameters for breeding could be defined to increase productivity of domestic ruminants by continuing certain evolutionary trajectorie

Responses of Rat P2X2 Receptors to Ultrashort Pulses of ATP Provide Insights into ATP Binding and Channel Gating

To gain insight into the way that P2X2 receptors localized at synapses might function, we explored the properties of outside-out patches containing many of these channels as ATP was very rapidly applied and removed. Using a new method to calibrate the speed of exchange of solution over intact patches, we were able to reliably produce applications of ATP lasting <200 μs. For all concentrations of ATP, there was a delay of at least 80 μs between the time when ATP arrived at the receptor and the first detectable flow of inward current. In response to 200-μs pulses of ATP, the time constant of the rising phase of the current was ∼600 μs. Thus, most channel openings occurred when no free ATP was present. The current deactivated with a time constant of ∼60 ms. The amplitude of the peak response to a brief pulse of a saturating concentration of ATP was ∼70% of that obtained during a long application of the same concentration of ATP. Thus, ATP leaves fully liganded channels without producing an opening at least 30% of the time. Extensive kinetic modeling revealed three different schemes that fit the data well, a sequential model and two allosteric models. To account for the delay in opening at saturating ATP, it was necessary to incorporate an intermediate closed state into all three schemes. These kinetic properties indicate that responses to ATP at synapses that use homomeric P2X2 receptors would be expected to greatly outlast the duration of the synaptic ATP transient produced by a single presynaptic spike. Like NMDA receptors, P2X2 receptors provide the potential for complex patterns of synaptic integration over a time scale of hundreds of milliseconds

Using rowers’ perceptions of on-water stroke success to evaluate sculling catch efficiency variables via a boat instrumentation system

Aim: An effective catch in sculling is a critical determinant of boat velocity. This study used rowers’ performance-based judgments to compare three measures of catch slip efficiency. Two questions were addressed: (1) would rower-judged Yes strokes be faster than No strokes? and (2) which method of quantifying catch slip best reflected these judgements? Methods: Eight single scullers performed two 10-min blocks of sub maximal on-water rowing at 20 strokes per minute. Every 30 s, rowers reported either Yes or No about the quality of their stroke at the catch. Results: It was found that Yes strokes identified by rowers had, on average, a moderate effect advantage over No strokes with a standardised effect size of 0.43. In addition, a quicker time to positive acceleration best reflected the change in performance; where the standardised mean difference score of 0.57 for time to positive acceleration was larger than the scores of 0.47 for time to PowerLine force, and 0.35 for time to 30% peak pin force catch slip measures. For all eight rowers, Yes strokes corresponded to time to positive acceleration occurring earlier than No strokes. Conclusion: Rower judgements about successful strokes was linked to achieving a quicker time to positive acceleration, and may be of the most value in achieving a higher average boat velocity

Vertebral anomalies in retired rugby players and the impact on bone density calculation of the lumbar spine

Dual energy X-ray absorptiometry (DXA) lumbar spine bone mineral density (BMD) measurements are subject to artificial elevation in the presence of structural abnormalities that are more common with age and injury, including osteoarthritis, fracture and osteophytes. The aims of this study were to investigate the presence of vertebral abnormalities on DXA scans in retired rugby players and a nonrugby control group, and to explore the effect of vertebral exclusion on the BMD diagnostic outcome. Eigty-seven male retired rugby players and 51 non-rugby controls from the UK Rugby Health Project participated in the study. Lumbar spine, total hip and femoral neck BMD were measured by DXA and scans were analyzed pre and post exclusion of anomalous vertebrae. Data were analyzed by age group to enable application of T-scores (≥50 y) and Z-scores (<50 y). From 138 lumbar spine scans, 66 required adjustment. One hundred twenty-two vertebral exclusions were made, and 12 lumbar spine scans (10 in retired rugby athletes) were un-reportable (<2 evaluable vertebrae). Vertebral exclusion significantly lowered lumbar spine BMD across all groups (p<0.01) and lowered the overall lowest T/Z-score. This effect was more pronounced in rugby groups (age <50 y, p < 0.001; age ≥50 y, p = 0.031) than in the control groups (age <50y, p = 0.125; age ≥50 y, p = 0.250). Vertebral abnormalities detected on lumbar spine scans, were highly prevalent and impacted final the T/Z-score in this cohort of retired rugby players. Current guidelines recommend exclusion of abnormalities from lumbar spine scans in adults aged ≥50 years. Our findings suggest that vertebral exclusions should also be applied to lumbar spine scans performed in those aged <50 years, particularly in former contact sports athletes, given their high risk for vertebral deformity