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Cell-cell fusion mediated by most paramyxovirus requires fusion protein (F) and attachment protein (H, HN, or G). The F protein is proteolytic cleaved to be fusogenically active. J paramyxovirus (JPV) has a unique feature in the family Paramyxoviridae: It encodes an integral membrane protein, syncytial protein (SP, formerly known as transmembrane protein, TM), which is essential in JPV-promoted cell-cell fusion (i.e., syncytial). In this study, we report that cleavage of SP is essential for its syncytial-promoting activity. We have identified the cleavage site of SP at amino acid residues 172 to 175, LKTG, and deletion of the "LKTG" residues abolished SP protein cleavage and its ability to promote cell-cell fusion. Replacing the cleavage site LKTG with a factor Xa protease cleavage site allows cleavage of the SP with factor Xa protease and restores its ability to promote cell-cell fusion. Furthermore, results from a hemifusion assay indicate that cleavage of SP plays an important role in the progression from the intermediate hemifusion state to a complete fusion. This work indicates that SP has many characteristics of a fusion protein. We propose that SP is likely a cell-cell fusion-promoting protein., Competing Interests: Competing interests statement:The authors declare no competing interest.

The US dairy industry has made great strides in improving animal health over many decades, which has driven substantial improvements in economic, social, and environmental sustainability. As consumer and corporate focus on climate continues to grow, the continued need to research and improve animal health and understand its connection with the environment is integral to the success of the dairy industry. Research to address these areas can be supported by national research programs and collaboration between them. The USDA and Dairy Management Inc established a collaborative research agreement in 2007; to date, this collaboration has not explicitly focused on animal health or its intersection with the environment. It is integral to the success of animal agriculture in an ever-changing sustainability landscape that animal health is addressed as a key piece of socioeconomic and environmental sustainability. An academic-industry stakeholder committee reached a consensus that supported this idea and identified that it is equally important to communicate these research findings with consumers in a way that resonates. The purpose of this Viewpoint article is to highlight that national research programs at the USDA Agricultural Research Service's National Animal Disease Center and Dairy Management Inc can and should play an important role in supporting and facilitating research at the intersection of animal health and sustainability broadly.

Longevity and herd turnover rate are becoming common topics of discussion as the dairy industry strives for continuous improvement in efficiency, profitability, animal welfare, and environmental sustainability. Having the most productive animal fill each slot on a dairy makes strategic replacement and the resulting herd turnover an important tool for producers. Dairy operations can be considered to have slots available to be occupied by cows. The number of slots available is governed by dairy characteristics including parlor size and facility design. With sustainability and profitability goals, producers should aim to fill each slot with the most productive animal. The advantages of a modest surplus of replacement heifers allowing for a higher herd turnover rate are examined and shown to improve herd profitability, enhance welfare, and reduce environmental impact. A model assuming constant demand for dairy foods is presented with increased herd turnover rate leading to more milk production per cow and reduced enteric methane emissions. This analysis demonstrates that all else being equal, raising more replacements (having a relatively higher herd turnover rate and decreased herd-level longevity) improves sustainability compared to management aimed at lower herd turnover rates. Understanding the drivers of herd turnover in dairy production has important implications for the components of one health: animal well-being, food production, and environmental stewardship. The present work examines one tool toward this goal, while the companion Currents in One Health by Nguyen et al, JAVMA, January 2023, takes a broader view of many aspects of dairy sustainability.

Dairy production provides high-quality, healthful nutrients to people on a planet soon to be inhabited by over 9 billion people. In doing so, it is ever more important to continuously improve the care of dairy animals, safeguard the environment we all share, and reliably produce nutritious food while maintaining the economic viability of the people working in dairy agriculture. In this paper, we review some associations between dairy consumption and human health along with the many interconnections between people, dairy animals, plants, and our shared environment. Understanding these relationships is an example of one health at work. In the US, total dairy consumption is at its highest point in the last 50 years, while many objective measures of cow health (eg, subclinical mastitis) have never been better since they have been recorded. Further, indications of food safety such as violative antibiotic residues in milk have never been lower. Dairy foods provide essential nutrients such as protein, vitamin B12, and calcium, while there is also evidence that they are protective against chronic conditions such as cardiovascular disease. Finally, the environmental footprint of dairy production in the US, as measured by metrics such as carbon dioxide-equivalent emissions intensity per unit of dairy nutrient, is the lowest it has ever been. The companion Currents in One Health by Nguyen et al, AJVR, January 2023, discusses some additional animal welfare and environmental impact implications of modern dairy production management in detail.

Diagnosis of feline lungworm, Aelurostrongylus abstrusus, is typically achieved by identifying larvae in feces following concentration through flotation or using the Baermann technique. This work presents observations on the usefulness of an indirect immunofluorescence antibody assay for detection of antibodies to this parasite in the sera of infected cats. Using first-stage larvae of A abstrusus and sera from both experimentally and naturally infected cats, it was determined that the test was fairly sensitive and did not cross-react with serum from an Ancylostoma braziliense (hookworm)-infected cat.

The establishment of cat- and dog-derived laboratory strains of Ancylostoma braziliense allowed for a morphological comparison of the eggs of A. braziliense, Ancylostoma caninum, and Ancylostoma tubaeforme. The length, width, and perimeter were determined for images of 10 eggs each of A. braziliense from the feces of a dog infected with a canine isolate and a cat infected with a feline isolate, A. caninum from dog feces, and A. tubaeforme from cat feces. The specific identity of the eggs was verified by polymerase chain reaction and restriction fragment length polymorphism by using HinfI and RsaI restriction digests followed by gel electrophoresis and sequencing. The mean (±SD) length, width, and perimeter and the length-to-width ratio (±SD) (all measurements are in micrometers) for the eggs of each species were as follows: A. braziliense eggs (combined cat and dog source), 53.03 ± 2.33, 36.37 ± 1.35, 140.43 ± 2.56, and 1.46 ± 0.11; A. caninum eggs, 63.92 ± 5.28, 39.21 ± 1.52, 161.99 ± 9.30, and 1.63 ± 0.13; and A. tubaeforme eggs, 61.44 ± 3.05, 39.14 ± 1.40, 157.98 ± 5.81, and 1.57 ± 0.08. The eggs of A. braziliense were significantly (P < 0.001) smaller than the eggs of A. caninum and A. tubaeforme in all dimensions. Thus, the eggs seem to be readily distinguishable using light microscopy, thereby aiding in species identification in fecal samples for a more comprehensive clinical picture and assessment of zoonotic risk.

Most stars form as members of large associations within dense, very cold (10 to 100 kelvin) molecular clouds. The nearby giant molecular cloud in Orion hosts several thousand stars of ages less than a few million years, many of which are located in or around the famous Orion Nebula, a prominent gas structure illuminated and ionized by a small group of massive stars (the Trapezium). We present x-ray observations obtained with the X-ray Multi-Mirror satellite XMM-Newton, revealing that a hot plasma with a temperature of 1.7 to 2.1 million kelvin pervades the southwest extension of the nebula. The plasma flows into the adjacent interstellar medium. This x-ray outflow phenomenon must be widespread throughout our Galaxy.