Assessment of dietary protein supplementation on milk productivity of commercial organic dairy farms during the grazing season.

Variability of protein and energy supply from pasture during the grazing season is a primary factor that can influence milk production of grazing organic dairy herds in the Northeast United States. This study evaluated the effects of altering the crude protein (CP) content of dietary supplements included in dairy rations fed to grazing organic dairy herds, on milk production and composition. Six commercial organic farms participated in a 6-wk trial, consisting of a 2-wk baseline period and 4-wk experimental period. Farms were paired by their summer 2017 milk urea nitrogen profile, and farms within each pair were assigned by restricted randomization to (1) continuation of their regular supplements (n = 3, control group, CON), or (2) supplement with altered CP as percentage of dry matter, formulated using an organic barley and roasted soybean mix (n = 3, treatment group, TRT). Throughout the 6-wk trial, individual milk samples were collected at 2 consecutive milkings weekly, while pasture and supplement samples, pasture measurements, and management information were collected twice weekly per farm. Data were statistically analyzed using the MIXED procedure of SAS (version 9.4, SAS Institute Inc.) for all parameters, and effects of treatment, week, and their interaction (treatment × week) were determined. The supplement CP (percentage of dry matter) during the baseline period was 13.5% for CON and 15.3% for TRT and 14.8% for CON and 19.3% for TRT during the experimental period. Milk production was 21% higher during the experimental period for TRT compared with CON (24.1 vs. 19.9 kg of milk per day, respectively). Milk production decreased for CON from wk 1 to wk 6 (23.6 vs. 20.4 kg of milk per day), whereas TRT maintained milked production from wk 1 to wk 6 (22.8 vs. 22.7 kg of milk per day). Milk composition was different between groups, with CON having higher fat percent (4.21 vs. 3.73%, respectively) and protein percent (3.15 vs. 3.05%, respectively) compared with TRT for the 6 wk. The milk urea nitrogen concentrations were similar between TRT and CON for the baseline period (11.9 vs. 12.1 mg/dL) and the final week of the experimental period (14.5 vs. 14.2 mg/dL). Although the effects of different diet CP fractions, particularly rumen undegradable protein and soluble protein, must be further delineated, these results indicate that altering the CP content of dietary supplements fed to grazing organic dairy cattle during the summer period in the Northeast US could be a useful mechanism to maintain milk production.

Separating NOM from salts in ion exchange brine with ceramic nanofiltration.

In drinking water treatment, natural organic matter (NOM) is effectively removed from surface water using ion exchange (IEX). A main drawback of using IEX for NOM removal is the production of spent IEX regeneration brine, a polluting waste that is expensive to discharge. In this work, we studied ceramic nanofiltration as a treatment for the spent NOM-rich brine, with the aim to reduce the volume of this waste and to recycle salt. Compared to polymeric nanofiltration, the fouling was limited. When NOM is rejected and concentrated, a clean permeate with the regeneration salt (NaCl) could be produced and reused in the IEX regeneration process. Bench scale studies revealed that NOM could be effectively separated from the NaCl solution by steric effects. However, the separation of NaCl from other salts present in the brine, such as Na2SO4, was not sufficient for reuse purposes. The low sulphate rejection was mainly due to the low zeta potential of the membrane at the high ionic strength of the brine. The permeate of the ceramic nanofiltration should be treated further to obtain a sodium chloride quality that can be recycled as a regenerant solution for ion exchange. Further treatment steps will benefit from the removal of NOM from the brine.

Mycoheterotrophic Epirixanthes (Polygalaceae) has a typical angiosperm mitogenome but unorthodox plastid genomes.

BACKGROUND AND AIMS: Fully mycoheterotrophic plants derive carbon and other nutrients from root-associated fungi and have lost the ability to photosynthesize. While mycoheterotroph plastomes are often degraded compared with green plants, the effect of this unusual symbiosis on mitochondrial genome evolution is unknown. By providing the first complete organelle genome data from Polygalaceae, one of only three eudicot families that developed mycoheterotrophy, we explore how both organellar genomes evolved after loss of photosynthesis. METHODS: We sequenced and assembled four complete plastid genomes and a mitochondrial genome from species of Polygalaceae, focusing on non-photosynthetic Epirixanthes. We compared these genomes with those of other mycoheterotroph and parasitic plant lineages, and assessed whether organelle genes in Epirixanthes experienced relaxed or intensified selection compared with autotrophic relatives. KEY RESULTS: Plastomes of two species of Epirixanthes have become substantially degraded compared with that of autotrophic Polygala. Although the lack of photosynthesis is presumably homologous in the genus, the surveyed Epirixanthes species have marked differences in terms of plastome size, structural rearrangements, gene content and substitution rates. Remarkably, both apparently replaced a canonical plastid inverted repeat with large directly repeated sequences. The mitogenome of E. elongata incorporated a considerable number of fossilized plastid genes, by intracellular transfer from an ancestor with a less degraded plastome. Both plastid and mitochondrial genes in E. elongata have increased substitution rates, but the plastid genes of E. pallida do not. Despite this, both species have similar selection patterns operating on plastid housekeeping genes. CONCLUSIONS: Plastome evolution largely fits with patterns of gene degradation seen in other heterotrophic plants, but includes highly unusual directly duplicated regions. The causes of rate elevation in the sequenced Epirixanthes mitogenome and of rate differences in plastomes of related mycoheterotrophic species are not currently understood.

Effect of Drive Row Ground Covers on Hop (Rosales: Cannabaceae) Yard Arthropod Pests in Vermont, USA.

Alternatives to pesticides are necessary for the management of hop (Humulus lupulus L.) arthropod pests. The three major arthropod pests in northeastern US hop production include two-spotted spider mite, Tetranychus urticae Koch, hop aphid Phorodon humuli (Schrank), and potato leafhopper, Empoasca fabae Harris. This 3-yr study (2012-2014) in Vermont investigated the effect of flowering ground covers on arthropod pest abundance. Hop cultivars 'Nugget' and 'Cascade' were evaluated under a strip-split plot experimental design. Ground cover treatments included 1) Control: mowed red clover (Trifolium pratense) and resident weeds, 2) Clover: red clover, and 3) Diverse: common yarrow (Achillea millefolium), beebalm (Monarda fistulosa), red clover, and annual sunflower (Helianthus annuus). Natural enemies were grouped by associated pest and indicated by our mixed model to be strong predictors of the number of hop aphid and potato leafhopper on hop plants. In year two, ground cover treatment had a significant effect on two-spotted spider mite abundance where fewer two-spotted spider mite were observed on hop plants in Diverse plots. The established, un-mowed Clover treatment was preferred by potato leafhopper over Diverse ground cover and hop plants. This revealed the potential for clover ground cover to serve as a trap crop for potato leafhopper management in northeastern hop yards. Our findings are evidence that ground covers implemented for conservation biological control may serve more specific pest management functions instead of or in addition to boosting top-down pest pressure.

Sex education in the schools: what role does it play?

Information regarding pubertal development, sex, pregnancy, and contraception should be provided to children and adolescents in an age-appropriate manner from parents, health care providers, and schools. This article reviews the medical literature on school sex education programs, adolescents' perception of these programs, and the role played by the media, parents, and health care professionals in sexual education of teens.

Effect of Organic Amendments on Soilborne and Foliar Diseases in Field-Grown Snap Bean and Cucumber.

Several paper mills in Wisconsin have programs for spreading paper mill residuals (PMR) on land. A growing number of vegetable farmers recognize the agronomic benefits of PMR applications, but there have been no investigations on the use of PMR for control of vegetable crop diseases. Our objective was to determine the effect of PMR amendments on soilborne and foliar diseases of cucumber and snap bean grown on a sandy soil. Raw PMR, PMR composted without bulking agent (PMRC), or PMR composted with bark (PMRBC) were applied annually in a 3-year rotation of potato, snap bean, and pickling cucumber. Several naturally occurring diseases were evaluated in the field, along with in situ field bioassays. All amendments suppressed cucumber damping-off and Pythium blight and foliar brown spot of snap bean. Both composts reduced the incidence of angular leaf spot in cucumber. In a separate field experiment planted with snap bean for two consecutive years, all amendments reduced common root rot severity in the second year. In a greenhouse experiment, the high rate of PMRBC suppressed anthracnose of snap bean. These results suggest that the application of raw and composted PMR to sandy soils has the potential to control several soilborne and foliar diseases.

The effect of portal perfusion on intrasplenic hepatocytes.

A newly developed rat model of portal diversion, in which the subcutaneously transposed spleen is perfused by splanchnic effluent as a result of portal vein ligation, has been used to monitor the effect of such portal perfusion on intrasplenic hepatocyte implants. Three groups of animals (controls, n = 42; transposed only, n = 70; and portally diverted, n = 58) received 2 million syngeneic liver cells. The number of hepatocytes in each spleen was assessed 5 days to 9 months later by direct counting of splenic sections. The transposed spleen was capable of supporting hepatocyte grafts even over long periods, although the number of cells was reduced in comparison with controls. Diversion of portal flow across the transposed spleen significantly increased hepatocyte numbers in the first 6 weeks (median number of cells (with inner quartile range), 1380 (70-1300) versus 600 (347-4050); n = 75), but no differences were detected thereafter. It appears that the initial lag phase of hepatocyte grafts can be partially abrogated by portal perfusion, but the subsequent 'proliferative' phase is unaffected. These effects correlate well with established theories on the importance of portal flow to the intact liver.

Powered metaphyseal stapler: an effective and simplified internal fixation system used in multiple types of podiatric surgery.

The multiplicity of types of usage of the powered stapler system in podiatric surgery were explored. The stapler system reduces surgical time and trauma, especially with complex reconstructive and repair procedures. The expedited surgical procedures along with minimized surgical trauma and comfortably implanted staples improved healing rate and less postoperative pain. The important criteria and indications for the usage of powered stapler fixation were reviewed. This relatively new system offers an effective alternative for internal fixation in the foot and ankle.

The growth of liver cells in the pancreas after intra-splenic implantation: the effects of portal perfusion.

A newly developed rat model of portal diversion, in which the pancreas gland is perfused by splanchnic effluent, has been used to monitor the effects of such portal perfusion on the development of isolated hepatocytes within the pancreatic parenchyma. Two groups of animals (control and portally-perfused) received intra-splenic hepatocyte implants (2 x 10(6) cells). The development of liver cells in the pancreas was then assessed histologically 10 days-9 months later. Portal diversion did not alter the incidence of hepatocytes within the pancreas as a whole (70% of all animals). However hepatocyte-islet rosettes (the intimate association between liver cells and endocrine tissue) were found in a significantly higher percentage of portally-perfused pancreases (92%) in comparison to controls (43%) 6 and 9 months after implantation. It appears that liver cell translocation from the spleen to the pancreas is dependent largely on factors associated with the implantation procedure itself. The growth of liver cells specifically around the islets of Langerhans, however, seems to be positively influenced by portal factors. These studies provide further evidence for the theory that extrahepatic liver cells are susceptible to local and systemic growth factors in a similar way to homotopic hepatocytes in the intact liver.

Transendothelial chemotaxis in vitro of human monocytes.

Porcine aortic vascular endothelial cells were grown to confluence on microporous PTFE membranes and incorporated into a two-compartment chemotaxis assembly. Human peripheral blood mononuclear cells (20-25% monocytes) were placed in the upper compartment and zymosan-activated human serum (ZAHS) as chemoattractant in the lower compartment. Over a 3 h period monocytes migrated across the endothelialized membrane and adhered to a collecting filter sited in the lower compartment. Addition of ZAHS to the cell suspension in the upper compartment virtually abolished the migration response whilst only minimal leucocyte migration was supported by the bare unendothelialized PTFE membrane. The extent of transendothelial monocyte chemotaxis was dependent upon the concentration of chemoattractant in the lower compartment and upon the cell density of the suspension containing monocytes. A confluency test of fluid flow across the endothelialized filter showed that monocyte migration could take place without disturbing endothelial barrier function. The culture system is easy to assemble and the method provides experimental versatility.

Transplanted isolated hepatocytes: effect of partial hepatectomy on proliferation of long-term syngeneic implants in rat spleen.

Proliferation of isolated hepatocytes in long-term splenic implants was assessed by flash labelling with a 1 pulse of tritiated thymidine (3H TdR). Cell kinetics showed that the basal labelling index was 0.9% which was greater than normal non-regenerating liver. Twenty four hours following partial hepatectomy the labelling index was 2.0%, a significant rise. These results suggest that hepatocytes transplanted to the spleen constitute a suitable model for screening putative hepatotrophic factors, and are of relevance in establishing clinically useful models of hepatocyte transplantation.

Human serum does contain a high molecular weight hepatocyte growth factor: studies pre- and post-hepatic resection.

Levels of a high molecular weight hepatotrophin were measured in human serum taken from patients before and 24 hours after undergoing major hepatic resection. In in-vitro rat hepatocyte cultures a 'hepatotrophin' enriched fraction of human serum induced the incorporation of tritiated thymidine into DNA in both pre and post-operative patients. Levels after hepatic resection were 2-3 fold higher than those achieved at the same protein concentration before operation in the same patient. The hepatotrophic factor had an apparent molecular weight of approximately 150,000 daltons, and was an anionic protein.

Observations on rat spleen reticulum during the development of syngeneic hepatocellular implants.

August rat hepatocytes isolated by collagenase perfusion were implanted directly into the spleens of syngeneic recipients. Graft development was monitored by a combination of staining techniques and when surviving hepatocytes were difficult to recognize by routine histology, indirect immunofluorescence permitted their rapid identification. Liver cells were found up to 21 months after transplantation, thus confirming the ability of the spleen to support hepatocellular grafts. The reticular framework of the spleen appears to play an important role. The reticulum mesh of the red pulp traps injected cells and there is rapid generation of reticulum fibres around them within 4 days. The subsequent proliferation and organization of liver cells into recognizable hepatic plates, glandular rosettes and acini was accompanied by the development of a rich and distinctive reticular scaffold with a pattern resembling that of regenerating splenic tissue.

The effects of intralipid and heparin on human monocyte and lymphocyte function.

A group of patients were studied during the infusion of Intralipid as part of a parenteral nutrition regimen. Peripheral blood lymphocyte function was unaffected, but monocyte function (chemotaxis) was significantly depressed. A group of healthy volunteers received an intravenous bolus of 20% Intralipid. Blood was taken before and 15 min afterward for immunological studies, and the same changes were seen following Intralipid. Prior subcutaneous injection of 5000 U of heparin did not affect either immunological parameter, but completely prevented the changes in monocyte function caused by Intralipid. Electronmicrographs of monocytes from volunteers after injection of Intralipid, and autoradiographs of cells incubated with 14C-Intralipid in vitro, showed phagocytosis of fat particles by monocytes. These data suggest that Intralipid can have potentially serious side effects on the immune system, and that they may be alleviated by the use of subcutaneous heparin.

Campylobacter as a cause of acute enteritis in children in South Australia. I. A 12-month study with controls.

During a 12-month period, we tested faecal samples from 386 children with acute enteritis and 332 controls by light and electron microscopy, and by bacterial and viral culture for pathogens, especially to assess the importance of campylobacter. Campylobacter alone was responsible for the illness in 17 patients (5%), and was second to salmonella among the bacterial agents, which were predominant in summer. Overall, rotavirus was the commonest identifiable cause of acute enteritis and was especially important in winter (with a rate of 49% in August). Thirty-five patients showed two or more agents. In 117 patients (30%) no pathogen was isolated or identified, suggesting that there are as yet unidentified agents in acute enteritis.