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Severe fever with thrombocytopenia syndrome (SFTS) is caused by SFTS virus (SFTSV), a new tickborne bandavirus identified in China in 2009 (1), and subsequently in South Korea in 2013 (2), [...]

Theileria orientalis (Ikeda) was first detected in New Zealand in 2012, becoming endemic in most of the North Island, and can cause incidences of anaemia and death. Research has been performed in New Zealand on the incidence and severity of infection. Through this research anecdotal evidence has been found to suggest a potential genetic susceptibility component in the response of the host to the parasite. To investigate the genetic susceptibility of cattle to T. orientalis (Ikeda), 99 calves born in 2016 as part of a separate experiment and grown in six grazing herds, were examined for their response to the parasite. In addition to measuring live weight, two blood collections were taken in the first four months of life which were used to measure packed cell volume by haematocrit and qPCR to assess parasite load. Heritability was calculated and was low for parasite load, but the result indicates that there is some potential to increase resistance through selective breeding. The mechanisms of the differences in parasite load were not elucidated in this research; however, significant variation was found among herds and sires, indicating that both genetic selection and environmental management could be utilised to reduce parasite load in growing calves. [ABSTRACT FROM AUTHOR]

Parthenogenesis is the development of an embryo from an unfertilized egg and is a common reproductive mechanism in invertebrate arthropods, especially insects and mites (1). One of the potential advantages [...]

Simple Summary: Spontaneous humeral fractures in first- and second-lactation dairy cows are recognized as a serious welfare problem in New Zealand. However, the condition is sporadic, which means that simple epidemiological descriptions and estimates of the extent of the problem are lacking. By combining the data from four independent studies using a multi-method approach, we found that their occurrence is more common than previously thought, with potentially up to 12% of farms and 4,620 dairy cattle affected in the 2013/2014 lactation season. Furthermore, the condition exclusively affects first- and second-lactation spring calving dairy cows, up to 4 months post-partum, and may affect multiple animals on the same farm, in the same season, and over multiple seasons, which are not always consecutive. We suggest that the evidence presented in this paper places an urgent requirement on the New Zealand dairy industry to undertake prompt action to understand the determinants of this epidemic. A multi-method approach integrating data from four independent sources was used to describe some key features of the epidemiology and estimate the herd and within-herd incidence of fractured humeri in New Zealand dairy cattle for the period 2007–2015. The first dataset was from a national case series where cases of humeral fractures in dairy cattle were identified by veterinarians across New Zealand between the 2007/2008 and 2011/2012 lactation seasons. The second dataset was from a pet food company based in the Waikato region, which collated the number of casualty first- and second-lactation cows found to have a fractured humerus post-slaughter in the 2014/2015 lactation season, and the third dataset was a case series conducted by veterinarians employed in a Waikato veterinary business, also from the 2014/2015 lactation season. For the final dataset, 505 randomly selected New Zealand dairy farmers completed a phone survey on the incidence of non-responsive, non-weight-bearing forelimb lameness in first- and second-lactation cows in the 2014/2015 lactation season. Using the telephone survey results, the within-herd and herd-level incidence of cases for first- and second-lactation dairy animals was calculated. The national case series reported 149 cases of humeral fractures in 22 dairy herds; the pet food case series identified 61 cases from 41 farms; and the practice-based case series found 14 cases from 10 farms. Humeral fractures exclusively affected first- and second-lactation dairy cows and had a peak incidence between calving and early mating. The national telephone survey found that non-weight-bearing forelimb lameness requiring euthanasia of first- or second-lactation cows occurred in 11.7% of herds, with a mean within-herd incidence of 2.6% for first lactation cows and 2.8% for second-lactation cows for affected herds. These combined datasets demonstrate that humeral fractures in young, lactating dairy cattle are more common than previously suspected and that they occur nationally and over multiple years on some farms. Further work on this condition is urgently required in New Zealand to establish cost-effective management practices that will reduce unnecessary animal suffering and waste. [ABSTRACT FROM AUTHOR]

While there is disagreement among mathematics educators about some aspects of its meaning, mathematical modeling generally involves taking a real-world scenario and translating it into the mathematical world (Niss, Blum, and Galbraith 2007). The complete modeling process involves describing situations posed in problems with mathematical concepts, relationships, diagrams, and symbolic expressions; manipulating and reasoning about those representations to derive new information; making predictions based on the results; and verifying predictions in the original problem situation (Lesh and Doerr 2003; Lesh and Zawojewski 2007). During the process of modeling, students apply what they already know as well as build and deepen their mathematical understanding of new mathematical content. For these reasons, modeling is important, which may be why the Common Core State Standards for Mathematics (CCSSI 2010) emphasizes the topic as not only a conceptual category in the high school curriculum but also a Standard for Mathematical Practice. As such, mathematical modeling should be part of mathematics learning, starting in the early grades. This implies that modeling is not an area of mathematics to be taught in isolation, but one that should permeate across content in the curriculum for all grades. In this article the authors consider the opportunities that students have to engage in tasks that strongly support modeling practices as well as those in which modeling is less visible. They describe examples of two types of tasks from existing curricula and online resources to illustrate their potential for supporting students in their modeling endeavors.

Outbreaks of humeral fractures in dairy cows have been reported in New Zealand for several years. Gross, histologic, and histomorphometric findings in the humerus from primiparous cows with spontaneous humeral fracture were compared to age-matched control cows. Affected cows had a complete nonarticular spiral fracture of the humerus. Histologically affected humeri had a thicker growth plate with abnormal architecture, thinner cortex with increased abnormal resorption, increased resorption in the distal humerus, decreased trabecular density, abnormal trabecular architecture, presence of growth arrest lines and woven bone formation. Histomorphometry showed reduction in bone volume, trabecular perimeter, and trabecular width. Cows grazed on fodder beet had thicker growth plates with an abnormal appearance compared with cows grazed on pasture, and cows with low/marginal liver copper concentration had more resorption cavities in the distal humerus and thinner cortical bone compared with cows with adequate liver copper concentration. Decreased trabecular density (OR = 249.5), abnormal cortical resorption (OR = 54.2), presence of woven bone formation in the proximal metaphysis (OR = 37.2), and the number of resorption cavities in the distal humerus were significantly associated with a high probability of fracture. Ribs had enlargement of the costochondral junction with fractures in different stages of healing. Histology of the ribs revealed abnormal growth plate appearance, presence of fracture lines, callus tissue, fibrosis, and microfractures. Cows with humeral fracture have osteoporosis due to decreased bone formation and increased bone resorption, likely associated with inadequate feed quality and perhaps copper deficiency leading to a reduction in bone strength and fracture. [ABSTRACT FROM AUTHOR]

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a tickborne bandavirus mainly transmitted by Haemaphysalis longicornis ticks in East Asia, mostly in rural areas. As of April 2022, the amplifying host involved in the natural transmission of SFTSV remained unidentified. Our epidemiologic field survey conducted in endemic areas in China showed that hedgehogs were widely distributed, had heavy tick infestations, and had high SFTSV seroprevalence and RNA prevalence. After experimental infection of Erinaceus amurensis and Atelerix albiventris hedgehogs with SFTSV, we detected robust but transitory viremias that lasted for 9-11 days. We completed the SFTSV transmission cycle between hedgehogs and nymph and adult H. longicornis ticks under laboratory conditions with 100% efficiency. Furthermore, naive H. longicornis ticks could be infected by SFTSV-positive ticks co-feeding on naive hedgehogs; we confirmed transstadial transmission of SFTSV. Our study suggests that the hedgehogs are a notable wildlife amplifying host of SFTSV in China. [ABSTRACT FROM AUTHOR]

Simple Summary: Collagen and collagen crosslinking are important determinants of bone strength. For the first time, collagen and its crosslink content were measured in the humerus from primiparous dairy cows with spontaneous humeral fracture due to osteoporosis from New Zealand. The results were compared with the humerus from unfractured dairy cows. Cows with a humeral fracture have a lower total collagen content but higher total collagen crosslink content compared with unfractured cows. The results suggest that protein/calorie undernutrition might be an important factor associated with the incidence of spontaneous humeral fractures in dairy cows from New Zealand. Numerous cases of spontaneous humeral fracture in primiparous dairy cows from New Zealand have prompted the study of the condition to establish probable causes or risk factors associated with the condition. Previous studies identified inadequate protein-calorie malnutrition as an important contributory factor. Earlier case studies also reported that ~50% of cows have low liver and/or serum copper concentration at the time of humeral fracture. Because copper is so closely associated with the formation of collagen cross-links, the aim of this study was to compare collagen and collagen crosslink content in the humerus from primiparous cows with and without humeral fractures and to determine the role of copper in the occurrence of these fractures. Humeri were collected from cows with and without humeral fractures, ground, and the collagen and collagen cross-link content measured using high-performance liquid chromatography. Collagen content was significantly higher in the humeri of cows without humeral fractures, while total collagen crosslink content was significantly higher in the humerus of cows with humeral fractures. These results indicate other factor/s (e.g., protein-calorie undernutrition) might be more important than the copper status in the occurrence of humeral fractures in dairy cows in New Zealand. [ABSTRACT FROM AUTHOR]

Pathogens lacking the enzymatic pathways for de novo purine biosynthesis are required to salvage purines and pyrimidines from the host environment for synthesis of DNA and RNA. Two key enzymes in purine salvage pathways are IMP dehydrogenase (GuaB) and GMP synthase (GuaA), encoded by the guaB and guaA genes, respectively. While these genes are typically found on the chromosome in most bacterial pathogens, the guaAB operon of Borrelia burgdorferi is present on plasmid cp26, which also harbors a number of genes critical for B. burgdorferi viability. Using molecular genetics and an experimental model of the tick-mouse infection cycle, we demonstrate that the enzymatic activities encoded by the guaAB operon are essential for B. burgdorferi mouse infectivity and provide a growth advantage to spirochetes in the tick. These data indicate that the GuaA and GuaB proteins are critical for the survival of B. burgdorferi in the infection cycle and highlight a potential difference in the requirements for purine salvage in the disparate mammalian and tick environments. doi: 10.1128/JB.00450-09

We previously reported that prenatal and suckling exposure to a maternal diet rich in animal fat leads to cardiovascular dysfunction in young adult rat offspring with subsequent development of dyslipidemia and hyperglycemia. We have further investigated glucose homeostasis in adult female offspring by euglycemic-hyperinsulinemic clamp and by dynamic assessment of glucose-stimulated insulin secretion in isolated, perifused pancreatic islet cells. Additionally, given the link between reduced mitochondrial DNA (mtDNA) content and the development of type 2 diabetes mellitus, we have measured mtDNA in organs from young adult animals. Sprague-Dawley rats were fed a diet rich in animal fat or normal chow throughout pregnancy and weaning. Infusion of insulin (5 mU*[kg.sup.-1]*[min.sup.-1]) resulted in a higher steady-state plasma insulin concentration in l-year-old offspring of fat-fed dams (OHF, n = 4) vs. offspring of control dams (OC, n = 4, P < 0.011. Glucose-stimulated insulin secretion in isolated islets from 9-mo-old OHF was significantly reduced compared with OC (n = 4, P < 0.05). Transmission electron micrography showed altered insulin secretory granule morphology in OHF pancreatic [3-cells. Kidney mtDNA was reduced in 3-mo-old OHF [16S-to-18S gene ratio: OC (n = 10) 1.05 [+ or -] 0.19 vs. OHF (n = 101 0.66 [+ or -] 0.06, P < 0.05]. At 6 mo, gene chip microarray of OHF aorta showed reduced expression of the mitochondrial genome. Prenatal and suckling exposure to a diet rich in animal fat leads to whole body insulin resistance and pancreatic [beta]-cell dysfunction in adulthood, which is preceded by reduced tissue mtDNA content and altered mitochondrial gene expression. dietary fats: insulin: islet cells: metabolic syndrome

Post-traumatic OA (PTOA) is often triggered by injurious, high-impact loading events which result in rapid, excessive chondrocyte cell death and a phenotypic shift in residual cells toward a more catabolic state. As such, the identification of a disease-modifying OA drug (DMOAD) that can protect chondrocytes from death following impact injury, and thereby prevent cartilage degradation and progression to PTOA, would offer a novel intervention. We have previously shown that urocortin-1 (Ucn) is an essential endogenous pro-survival factor that protects chondrocytes from OA-associated pro-apoptotic stimuli. Here, using a drop tower PTOA-induction model, we demonstrate the extent of Ucn's chondroprotective role in cartilage explants exposed to excessive impact load. Using pathway-specific agonists and antagonists, we show that Ucn acts to block load-induced intracellular calcium accumulation through blockade of the non-selective cation channel Piezo1 rather than TRPV4. This protective effect is mediated primarily through the Ucn receptor CRF-R1 rather than CRF-R2. Crucially, we demonstrate that the chondroprotective effect of Ucn is maintained whether it is applied pre-impact or post-impact, highlighting the potential of Ucn as a novel DMOAD for the prevention of injurious impact overload-induced PTOA. [ABSTRACT FROM AUTHOR]

Severe fever with thrombocytopenia syndrome virus (SFTSV) is spreading rapidly in Asia. This virus is transmitted by the Asian longhorned tick (Haemaphysalis longicornis), which has parthenogenetically and sexually reproducing populations. Parthenogenetic populations were found in ≥15 provinces in China and strongly correlated with the distribution of severe fever with thrombocytopenia syndrome cases. However, distribution of these cases was poorly correlated with the distribution of populations of bisexual ticks. Phylogeographic analysis suggested that the parthenogenetic population spread much faster than bisexual population because colonization is independent of sexual reproduction. A higher proportion of parthenogenetic ticks was collected from migratory birds captured at an SFTSV-endemic area, implicating the contribution to the long-range movement of these ticks in China. The SFTSV susceptibility of parthenogenetic females was similar to that of bisexual females under laboratory conditions. These results suggest that parthenogenetic Asian longhorned ticks, probably transported by migratory birds, play a major role in the rapid spread of SFTSV. [ABSTRACT FROM AUTHOR]

This study aimed to investigate whether the infection intensity of Theileria orientalis Ikeda type organisms within Haemaphysalis longicornis larvae and nymph stages fluctuated over 6 mo after feeding as larvae on infected calves in the field. Naı¨ve larvae, hatched from eggs, were fed on infected calves for 5 days while contained within cotton socks glued over the calves’ ears. Larvae were first sampled immediately post-feeding and then sampled every 3 wk for 23 wk in total, after molting to nymphs. All larvae and nymphs were tested for T. orientalis Ikeda organisms using quantitative PCR. The qPCR results showed that the infection intensity of Haemaphysalis longicornis larvae and nymphs was not constant over the sampling period, and after initially dropping after molting to nymphs, it then rose with fasting to a maximum at 17 and 23 wk post-feeding. The significant rise in T. orientalis Ikeda organisms observed at 23 wk postfeeding may explain why more severe clinical cases of bovine theileriosis in New Zealand are seen in the spring when nymphs are the predominant instar questing. [ABSTRACT FROM AUTHOR]