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Simple Summary: Deer keds are parasitic flies (Diptera) that feed on deer. They occasionally bite humans, resulting in localized skin irritation. There are many knowledge gaps persisting around the distribution of deer keds and the pathogenic microorganisms that they may transmit. In this study, 99 deer keds were collected from white-tailed deer across Massachusetts (northeastern United States). These deer keds were screened for the presence of six tick-borne pathogens using real-time PCR testing. A tick-borne bacterium, Anaplasma phagocytophilum, was found in almost 1/3 of the tested deer keds. Because of host association patterns of defined A. phagocytophilum strains, these are most likely not pathogenic to humans. No other pathogens tested were identified. These results suggest that the risk of the transmission of pathogens to humans by deer keds may be low. Based on the feeding behavior of deer keds (feeding on only one host compared to some ectoparasites that may require blood meals from multiple hosts), deer keds may be a useful tool for the monitoring and surveillance of pathogens associated with deer. Future work is needed to further assess the potential significance of deer keds to public, wildlife, and veterinary health. Deer keds (Lipoptena spp. and Neolipoptena ferrisi) are hematophagous ectoparasites that primarily infest white-tailed deer (Odocoileus virginianus) and other cervids in the United States. The distribution of deer keds in the northeastern United States and the pathogens they harbor remains relatively unexplored. In this study, we examined the geographical distribution and pathogen prevalence of deer keds in Massachusetts by collecting samples from white-tailed deer and testing for tick-borne pathogens. Deer keds were collected across the state, including in four previously unrecorded counties, indicating a wide distribution. Pathogen screening revealed the presence of Anaplasma phagocytophilum DNA in 30% of the keds, but no other pathogens were detected. The medical and biological significance of detecting A. phagocytophilum DNA in deer keds requires future studies. This research provides a baseline for the distribution and pathogen prevalence of deer keds in Massachusetts and highlights the potential of deer keds as sentinels for monitoring deer-associated microbes. [ABSTRACT FROM AUTHOR]

Simple Summary: When a species expands its geographic range, it may displace similar species in the new region. In the northeastern USA, lone star ticks (Amblyomma americanum) have encroached on the range of blacklegged ticks (Ixodes scapularis), becoming more numerous in a wide range of habitats. Both species carry human disease agents, and both rely heavily on white-tailed deer (Odocoileus virginianus) for reproduction. We used 1265 yard surveys conducted in 2011–2024 to document the timing and pattern of lone star tick establishment on the island of Martha's Vineyard (MV), Massachusetts. Increases in lone star ticks coincided with new cases of ehrlichiosis and reports of the alpha gal syndrome "red meat" allergy. To provide an index of current tick abundance, we used drag sampling to quantify the numbers of each tick species per kilometer of trail at 14 study sites on eastern MV where both species have coexisted for a decade. Lone star ticks are now ubiquitous at the study sites, while blacklegged ticks are persisting at relatively high levels in the woods. We conclude that the risk of human exposure to pathogens carried by blacklegged ticks remains high and is complemented by additional health risks associated with lone star ticks. In the northeastern USA, the distribution of lone star ticks (Amblyomma americanum) has expanded northward in recent decades, overlapping with the range of blacklegged ticks (Ixodes scapularis). Blacklegged ticks carry pathogens for diseases such as Lyme, babesiosis, and anaplasmosis, while bites from lone star ticks cause other diseases and the alpha-gal syndrome allergy. Lone star ticks can become so abundant that they are perceived as more of a public health threat than blacklegged ticks. Using the island of Martha's Vineyard, Massachusetts, as a case study, we analyzed data from a total of 1265 yard surveys from 2011 to 2024 to document lone star tick presence and subsequent expansion from two peripheral areas, Chappaquiddick and Aquinnah, to all six towns. The timing of lone star tick expansion on Martha's Vineyard closely matched an increase in tick submissions to a pathogen testing center. At Chappaquiddick, drag sampling carried out in June 2023 and 2024 showed that both tick species were most common at wooded sites, where blacklegged nymphs were somewhat more abundant than lone star nymphs. However, lone star ticks occurred in a wider range of natural and peridomestic habitats than blacklegged nymphs, making them far more challenging for people to avoid and manage. [ABSTRACT FROM AUTHOR]

In this study, we explored the effects of chronic stress on lumpfish (Cyclopterus lumpus) physiological, immune response, health, and plasma free amino acids. 3 groups of lumpfish were exposed to 1-minute air exposure. 1 group was exposed to stress once per week, a second group exposed 2 times per week, and a third group exposed 4 times per week. The present study revealed significant alterations in immunity and increased nutritional demands, particularly the branched chain amino acids and lysine. Cortisol levels fluctuated, with significantly higher levels halfway through the experiment on the groups that were stressed more often. Though, by the end of the experiment, there were no significant differences in cortisol levels between groups. Regardless of stress exposure, cataract developed in virtually all sampled fish, pointing toward a potential dietary imbalance. A transient immunomodulation of stress was visible. While in early stages stress had an immune enhancing effect, as seen by the increase in plasma nitric oxide and peroxidase in the group most frequently exposed to stress, these differences were not apparent by the end of the experiment. Additionally, the worst health condition was found in this group. Our results underscore the complex interplay between stress, immunity and nutrition, highlighting the need for tailored dietary strategies and improved rearing practices. [ABSTRACT FROM AUTHOR]