Assessment of the current performance of grazing infrastructure across Irish dairy farms.

The increased average Irish dairy herd size in a post-quota environment has put heightened pressure on grazing infrastructure. In a rotational grazing system, grazing infrastructure consists of the paddock system, which delineates the grazing areas into appropriately sized grazing parcels, and the roadway network, which connects these paddocks to the milking parlor. Where herd size has increased without corresponding adaptations to the infrastructure, farm management and roadway network performance has been affected. The links between suboptimal grazing infrastructure and roadway network efficiency are poorly understood and not widely documented. The aims of this study were to (1) analyze the effect of herd expansion and paddock size on pasture allocations per paddock, (2) identify the factors that affect the total distance walked per year, and (3) create a metric to compare the efficiency of roadway networks across farms of varying grazing platforms. A sample population of 135 Irish dairy farms with a median herd size of 150 cows was used for this analysis. Herds were split into the following 5 categories: <100 cows, 100 to 149 cows, 150 to 199 cows, 200 to 249 cows, and ≥250 cows. Herds with ≥250 cows had a greater number of paddocks per farm and rotated around the grazing paddocks more frequently, with 46% of paddocks only suitable for 12 h allocations relative to herd size, compared with just 10% to 27% of paddocks for herds with <100 cows to herds with 200-249 cows. When predicting the total distance walked per year on each study farm, the mean distance from a paddock to the milking parlor was the strongest indicator (R2 = 0.8247). Other metrics, such as herd size, have failed to account for the location of the milking parlor relative to the grazing platform. The creation of the relative mean distance from a paddock to milking parlor (RMDMP) metric allowed the calculation of a farm's roadway network efficiency for moving the herd between paddocks and the milking parlor. The analyzed farms increased their efficiency in terms of RMDMP (0.34-40.74%) as they increased herd size post quota. However, the position of new additional paddocks relative to the milking parlor substantially affected their RMDMP.

Comparison of modelling techniques for milk-production forecasting.

The objective of this study was to assess the suitability of 3 different modeling techniques for the prediction of total daily herd milk yield from a herd of 140 lactating pasture-based dairy cows over varying forecast horizons. A nonlinear auto-regressive model with exogenous input, a static artificial neural network, and a multiple linear regression model were developed using 3 yr of historical milk-production data. The models predicted the total daily herd milk yield over a full season using a 305-d forecast horizon and 50-, 30-, and 10-d moving piecewise horizons to test the accuracy of the models over long- and short-term periods. All 3 models predicted the daily production levels for a full lactation of 305 d with a percentage root mean square error (RMSE) of ≤ 12.03%. However, the nonlinear auto-regressive model with exogenous input was capable of increasing its prediction accuracy as the horizon was shortened from 305 to 50, 30, and 10 d [RMSE (%)=8.59, 8.1, 6.77, 5.84], whereas the static artificial neural network [RMSE (%)=12.03, 12.15, 11.74, 10.7] and the multiple linear regression model [RMSE (%)=10.62, 10.68, 10.62, 10.54] were not able to reduce their forecast error over the same horizons to the same extent. For this particular application the nonlinear auto-regressive model with exogenous input can be presented as a more accurate alternative to conventional regression modeling techniques, especially for short-term milk-yield predictions.

Factors affecting energy efficiency in herringbone and rotary milking parlours.

The United Nations Sustainable Development Goals aim to double the productivity of small-medium food producers (2015-2030), while food demand is estimated to increase by 60 % by 2050. The objectives of this paper were to identify and quantify the relationship between energy efficiency and milking efficiency, identify the main energy consuming processes associated with milking, and investigate whether milking efficiency, energy efficiency or the relationship between them varies depending on parlour type. Energy and milking efficiency data from 26 pasture-based dairy farms in the Republic of Ireland were analysed (17 herringbone, nine rotary). Energy consumption was monitored continuously on the herringbone farms and for two distinct, seven-day periods (observation periods 1 and 2) for the rotary farms. Milking performance was monitored for all 26 farms during these periods. During the observation periods, the rotary farms achieved superior energy efficiency (29.85 Wh kgMilk-1) and milking efficiency (152 cows/hour) than the herringbone farms (32.83 Wh kgMilk-1, 97 cows/hour). Moderate correlations existed between milking efficiency (cows/hour) and energy efficiency (Wh kgMilk-1) for rotary (r = -0.58, R2 = 0.34) and herringbone (r = -0.44, R2 = 0.19). These results indicated that higher levels of milking efficiency were moderately correlated with improved energy efficiency.

Post-Ischemic Reorganization of Sensory Responses in Cerebral Cortex.

Sensorimotor integration is critical for generating skilled, volitional movements. While stroke tends to impact motor function, there are also often associated sensory deficits that contribute to overall behavioral deficits. Because many of the cortico-cortical projections participating in the generation of volitional movement either target or pass-through primary motor cortex (in rats, caudal forelimb area; CFA), any damage to CFA can lead to a subsequent disruption in information flow. As a result, the loss of sensory feedback is thought to contribute to motor dysfunction even when sensory areas are spared from injury. Previous research has suggested that the restoration of sensorimotor integration through reorganization or de novo neuronal connections is important for restoring function. Our goal was to determine if there was crosstalk between sensorimotor cortical areas with recovery from a primary motor cortex injury. First, we investigated if peripheral sensory stimulation would evoke responses in the rostral forelimb area (RFA), a rodent homologue to premotor cortex. We then sought to identify whether intracortical microstimulation-evoked activity in RFA would reciprocally modify the sensory response. We used seven rats with an ischemic lesion of CFA. Four weeks after injury, the rats' forepaw was mechanically stimulated under anesthesia and neural activity was recorded in the cortex. In a subset of trials, a small intracortical stimulation pulse was delivered in RFA either individually or paired with peripheral sensory stimulation. Our results point to post-ischemic connectivity between premotor and sensory cortex that may be related to functional recovery. Premotor recruitment during the sensory response was seen with a peak in spiking within RFA after the peripheral solenoid stimulation despite the damage to CFA. Furthermore, stimulation evoked activity in RFA modulated and disrupted the sensory response in sensory cortex, providing additional evidence for the transmission of premotor activity to sensory cortex and the sensitivity of sensory cortex to premotor cortex's influence. The strength of the modulatory effect may be related to the extent of the injury and the subsequent reshaping of cortical connections in response to network disruption.

Post-ischemic reorganization of sensory responses in cerebral cortex.

Introduction: Sensorimotor integration is critical for generating skilled, volitional movements. While stroke tends to impact motor function, there are also often associated sensory deficits that contribute to overall behavioral deficits. Because many of the cortico-cortical projections participating in the generation of volitional movement either target or pass-through primary motor cortex (in rats, caudal forelimb area; CFA), any damage to CFA can lead to a subsequent disruption in information flow. As a result, the loss of sensory feedback is thought to contribute to motor dysfunction even when sensory areas are spared from injury. Previous research has suggested that the restoration of sensorimotor integration through reorganization or de novo neuronal connections is important for restoring function. Our goal was to determine if there was crosstalk between sensorimotor cortical areas with recovery from a primary motor cortex injury. First, we investigated if peripheral sensory stimulation would evoke responses in the rostral forelimb area (RFA), a rodent homologue to premotor cortex. We then sought to identify whether intracortical microstimulation-evoked activity in RFA would reciprocally modify the sensory response. Methods: We used seven rats with an ischemic lesion of CFA. Four weeks after injury, the rats' forepaw was mechanically stimulated under anesthesia and neural activity was recorded in the cortex. In a subset of trials, a small intracortical stimulation pulse was delivered in RFA either individually or paired with peripheral sensory stimulation. Results: Our results point to post-ischemic connectivity between premotor and sensory cortex that may be related to functional recovery. Premotor recruitment during the sensory response was seen with a peak in spiking within RFA after the peripheral solenoid stimulation despite the damage to CFA. Furthermore, stimulation in RFA modulated and disrupted the sensory response in sensory cortex. Discussion: The presence of a sensory response in RFA and the sensitivity of S1 to modulation by intracortical stimulation provides additional evidence for functional connectivity between premotor and somatosensory cortex. The strength of the modulatory effect may be related to the extent of the injury and the subsequent reshaping of cortical connections in response to network disruption.

Experimental transmission of vesicular stomatitis New Jersey virus from Simulium vittatum to cattle: clinical outcome is influenced by site of insect feeding.

Vesicular stomatitis New Jersey virus (VSNJV) is an insect-transmitted Rhabdovirus causing vesicular disease in domestic livestock including cattle, horses, and pigs. Natural transmission during epidemics remains poorly understood, particularly in cattle, one of the most affected species during outbreaks. This study reports the first successful transmission of VSNJV to cattle by insect bite resulting in clinical disease. When infected black flies (Simulium vittatum Zetterstedt) fed at sites where VS lesions are usually observed (mouth, nostrils, and foot coronary band), infection occurred, characterized by local viral replication, vesicular lesions, and high neutralizing antibody titers (> 1: 256). Viral RNA was detected up to 9 d postinfection in tissues collected during necropsy from lesion sites and lymph nodes draining those sites. Interestingly, when flies were allowed to feed on flank or neck skin, viral replication was poor, lesions were not observed, and low levels of neutralizing antibodies (range, 1:8-1:32) developed. Viremia was never observed in any of the animals and infectious virus was not recovered from tissues on necropsies performed between 8 and 27 d postinfection. Demonstration that VSNJV transmission to cattle by infected black flies can result in clinical disease contributes to a better understanding of the epidemiology and potential prevention and control methods for this important disease.

S-laminin expression in adult and developing retinae: a potential cue for photoreceptor morphogenesis.

The development of the neural retina follows a stereotyped time course that begins with an undifferentiated neuroepithelium populated by multipotential progenitor cells and ends with a highly differentiated tissue containing diverse cell types. The identities of the factors that guide this differentiation have remained elusive; a likely location for such factors, however, is the extracellular environment. Here, we show that the extracellular matrix component s-laminin is present in the neural retina, that s-laminin expression parallels the differentiation of rod photoreceptors, that photoreceptors interact with s-laminin in vitro, and that antibodies to s-laminin profoundly reduce the appearance of cells that express rhodopsin in vitro. These data suggest that s-laminin plays a role in the differentiation of the neural retina and provide evidence that the composition of the extracellular matrix may be an important determinant of retinal differentiation.

Evaluation of the pertussis components of diphtheria-tetanus-pertussis vaccine.

The adjuvant and antigen components of the pertussis fraction of diphtheria-tetanus-pertussis (DTP) vaccine were evaluated. Four preparations of DTP vaccine composed of either whole cell (Wc) or extracted (E) pertussis antigen combined with either an aluminum phosphate (Ph) or alum (Al) adjuvant were compared. Local reactions were similar in all four vaccines after the first two immunizations but were significantly increased in incidence and severity following the third immunization with vaccine WcPh. This appeared to be due to the Ph adjuvant rather than the antigen component. Febrile reactions were experienced more often (P = .0009) and with higher temperatures (P = .0001) with the WcPh vaccine following the first immunization. This appeared to be due to the Wc component. Comparing the pooled Wc groups with the pooled E groups revealed a greater febrile response in the Wc group after both the first (P = .0008) and the second (P = .03) immunization. Local reactions appear temporally and etiologically to be distinct from febrile reactions. The pooled Wc antigen group produced a higher geometric mean titer than the pooled E antigen group (P = .05). Serologic responses, with respect to geometric mean titer, were not significantly different among the individual vaccines. This study suggests that the combination of whole cell and aluminum phosphate, which is currently in use in the United States, is probably not the optimal formulation for pertussis vaccine.

Effect of early immunization on antibody response to reimmunization with measles vaccine as demonstrated by enzyme-linked immunosorbent assay (ELISA).

A measles epidemic in San Antonio, Texas provided a population of children who were immunized at less than or equal to 10 months of age and reimmunized at greater than or equal to 15 months of age. Of these children, 302 were evaluated for measles antibody by the sensitive enzyme-linked immunosorbent assay (ELISA), and their responses were compared with those of 300 children who had been immunized at the customary time (greater than or equal to 15 months) with a single immunization. There were only five seronegative findings in each group. The children immunized at the customary time did have significantly higher (P less than .001) antibody titers than the children immunized at less than or equal to 10 months and reimmunized at greater than or equal to 15 months. These results indicate that early immunization followed by reimmunization may be indicated when young infants are at significant risk of measles exposure. This approach should not create an increased number of serologically nonresponsive children when reimmunized at greater than or equal to 15 months.

Illness with fatalities in premature infants: association with an intravenous vitamin E preparation, E-Ferol.

Three clusters of an unusual syndrome in premature infants were investigated in three intensive care nurseries in 1984. A retrospective cohort study of 68 infants weighing less than or equal to 1,250 g at birth and surviving at least 72 hours revealed that in 13 infants ascites developed and in four at least two of the following abnormal laboratory values were found within a seven-day period: serum direct bilirubin greater than or equal to 2 mg/dL, blood urea nitrogen greater than or equal to 40 mg/dL or serum creatinine greater than or equal to 2 mg/dL, and platelet count less than or equal to 60,000/microL. All cases occurred after the introduction and use of intravenous E-Ferol, a vitamin E preparation that was new on the market when the clusters were reported. All 17 case infants but only 23 of 51 (45%) noncase infants received E-Ferol (P less than .0001). Case and noncase infants were similar with respect to other complications and to receipt of medications and parenteral nutrition. A dose-response relationship was found; cases occurred in infants receiving E-Ferol dosages of greater than 20 U/kg/d. Case infants who had higher daily doses of E-Ferol had a shorter latency. No new cases were reported after use of E-Ferol was stopped. Results of these investigations led to a nationwide recall of intravenous E-Ferol.

Resting energy expenditures measured by indirect calorimetry are higher in preadolescent children with cystic fibrosis than expenditures calculated from prediction equations.

OBJECTIVE: This study compared measured resting energy expenditures to resting energy expenditures calculated using Harris-Benedict equations (HBEs) and the Cystic Fibrosis Consensus Committee equations (CFCCEs). DESIGN: We studied 31 preadolescent boys and girls with cystic fibrosis who ranged in age from 3.25 to 12.75 years old. The patients were afebrile and not in pulmonary distress. Measured resting energy expenditures were determined using a portable metabolic measurement cart with fully automated calibration and data management. The measured resting energy expenditures obtained were compared with values obtained using HBEs and CFCCEs. RESULTS: For each patient, the measured resting energy expenditure value was above the predicted resting energy expenditure values derived from HBEs (P < or = .0001) and CFCCEs (P < or = .01). APPLICATIONS: The HBEs and the CFCCEs underestimated the energy expenditures of the study population by 13% and 8%, respectively. These findings support the usefulness of the measurement of energy expenditures in determining the energy needs of preadolescent patients with cystic fibrosis. In clinical practice, the resting energy expenditures would be multiplied by activity coefficients to determine the total daily energy expenditures of this population.

Adult age comparisons in the processing of event frequency information.

The usual superiority in frequency-of-occurrence judgments of younger vs. older subjects was hypothesized to result from greater strategic encoding of the materials conveying frequency information. A subject-paced, visual search task was designed to control nontarget word encoding. Relative frequency judgments for the nontarget word pairs were equally accurate for younger and older subjects, and performance of both groups was above chance. Results suggest that strategic cover-task encoding can induce age differences in incidental frequency processing. Consistent with a nonoptimal as opposed to an optimal view, automatic processes require only minimal capacity for above-chance performance, but additional strategic resources can increase performance. When such additional resources are used more by younger than by older subjects, the former are better in frequency performance.

Metamemory in older adults: the role of monitoring in serial recall.

Older and younger adults were asked to think aloud while studying sets of pictures matched in difficulty for immediate serial recall. When instructed only to remember, young adults tended to study longer, rehearse more, and recall better than did older adults on the most difficult lists. Young adults were also much more likely to spontaneously test themselves during study in the most difficult condition. Older adult groups instructed either to study longer or to self-test, both showed improved recall. Only the older adults who had been instructed to self-monitor, however, recalled better on tests of short-term maintenance and generalization; overt rehearsal data showed that these older adults continued to test themselves. Metamemory deficits may be present with older adults when a strategy, like self-testing, is needed to generate metamemorial knowledge. Strategies such as self-testing can be easily taught, however, and they hold promise of being useful across situations.

How shared are age-related influences on cognitive and noncognitive variables?

Several theories have suggested that age-related declines in cognitive processing are due to a pervasive unitary mechanism, such as a decline in processing speed. Structural equation model tests have shown some support for such common factor explanations. These results, however, may not be as conclusive as previously claimed. A further analysis of 4 cross-sectional data sets described in Salthouse, Hambrick, and McGuthry (1998) and Salthouse and Czaja (2000) found that although the best fitting model included a common factor in 3 of the data sets, additional direct age paths were significant, indicating the presence of specific age effects. For the remaining data set, a factor-specific model fit at least as well as the best fitting common factor model. Three simulated data sets with known structure were then tested with a sequence of structural equation models. Common factor models could not always be falsified--even when they were false. In contrast, factor-specific models were more easily falsified when the true model included a unitary common factor. These results suggest that it is premature to conclude that all age-related cognitive declines are due to a single mechanism. Common factor models may be particularly difficult to falsify with current analytic procedures.

Are emotionally charged lures immune to false memory?

Using the Deese-Roediger-McDermott task and E. Tulving's (1985) remember-know judgments for recognition memory, the authors explored whether emotional words can show the false memory effect. Participants studied lists containing nonemotional, orthographic associates (e.g., cape, tape, ripe; part, perk, dark) of either emotional (e.g., rape) or nonemotional (e.g., park) critical lures. This setup produced significant false "remembering" of emotional lures, even though initially no emotional words appeared at study. When 3 emotional nonlure words appeared at study, emotional-lure false recognition more than doubled. However, when these 3 study words also appeared on the recognition test, false memory for the emotional lures was reduced. Across experiments, participants misremembered nonemotional lures more often than they did emotional lures, but they were more likely to rate emotional lures as "remembered," once they had been recognized as "old." The authors discuss findings in light of J. J. Freyd and D. H. Gleave's (1996) criticisms of this task.

Failure of porcine reproductive and respiratory syndrome virus to replicate in porcine endothelial cell cultures.

Clinical, gross, and microscopic pathologic and immunohistochemical findings in pigs infected with porcine reproductive and respiratory syndrome virus (PRRSV) suggest that PRRSV may replicate in endothelial cells. Endothelial cell cultures from porcine aorta and pulmonary artery were tested for susceptibility to various strains of PRRSV. Cultures were identified as endothelium by light microscopy and immunohistochemical staining for P-selectin and von Willebrand factor. Five strains of PRRSV, i.e., the National Veterinary Services Laboratories, Ames, IA PRRSV strain 130-PDV and 4 field strains isolated from pneumonic lungs, failed to replicate in these porcine large-vessel endothelial cell cultures.

Contact transmission of vesicular stomatitis virus New Jersey in pigs.

OBJECTIVE: To determine how viral shedding and development or lack of clinical disease relate to contact transmission of vesicular stomatitis virus New Jersey (VSV-NJ) in pigs and determine whether pigs infected by contact could infect other pigs by contact. ANIMALS: 63 pigs. PROCEDURE: Serologically naive pigs were housed in direct contact with pigs that were experimentally inoculated with VSV-NJ via ID inoculation of the apex of the snout, application to a scarified area of the oral mucosa, application to intact oral mucosa, or ID inoculation of the ear. In a second experiment, pigs infected with VSV-NJ by contact were moved and housed with additional naive pigs. Pigs were monitored and sampled daily for clinical disease and virus isolation and were serologically tested before and after infection or contact. RESULTS: Contact transmission developed only when vesicular lesions were evident. Transmission developed rapidly; contact pigs shed virus as early as 1 day after contact. In pens in which contact transmission was detected, 2 of 3 or 3 of 3 contact pigs were infected. CONCLUSIONS AND CLINICAL RELEVANCE: Transmission was lesion-dependent; however, vesicular lesions often were subtle with few or no clinical signs of infection. Contact transmission was efficient, with resulting infections ranging from subclinical (detected only by seroconversion) to clinical (development of vesicular lesions). Long-term maintenance of VSV-NJ via contact transmission alone appears unlikely. Pigs represent an efficient large-animal system for further study of VSV-NJ pathogenesis and transmission.

Blastopore formation in the animal hemisphere: functional inversion of gastrulation by centrifugation of Xenopus laevis eggs.

Eggs of Xenopus laevis and many other amphibians contain a gradient of yolk platelets along the animal-vegetal axis. Small platelets predominate in the animal hemisphere, and a boundary between medium and large yolk platelets exists near the equator. The blastopore forms at this boundary at the beginning of gastrulation, in the vegetal hemisphere. Does this boundary have a role in determination of the position of the blastopore, or does cortical information predominate? Past experiments using 1g to invert the egg showed a distinct tendency to form the blastopore in the original vegetal hemisphere. Our experiments, however, have used 20g centrifugation to achieve a more complete inversion of the yolk gradient. The blastopore formed in the original animal hemisphere in >95% of surviving gastrulae, if centrifugation was begun at normalized time 0.20-0.25 of the first cell cycle. Nearly normal larvae (DAI grades 4 and 5) form in 64% of cases (ave. DAI = 3.2). These data support the idea that the position of the blastopore depends on the position of the egg's internal contents rather than cortical determinants.

Cough in pediatric patients receiving angiotensin-converting enzyme inhibitor therapy or angiotensin receptor blocker therapy in randomized controlled trials.

The incidence of cough in children receiving antihypertension therapy with angiotensin-converting enzyme inhibitors (ACEis) or angiotensin receptor blockers (ARBs) is unknown. We analyzed patient-level data from eight randomized trials for the treatment of pediatric hypertension, six of them involving ACEis and two involving ARBs. The incidence of cough in children receiving ACEis (reported cough, 3.2%) was similar to that in children receiving ARBs (reported cough, 1.8%) (P = 0.34). Reports of cough were lower in children than in adults.