Six isolates (12.2%, n = 6/49) were identified as GG3, which were cultured from rainbow trout (n = 3) and steelhead trout (n = 3). Two isolates were identified as GG2 (4.1%, n = 2/49) and were from ornamental fish. No GG4 isolates were cultured in this study. The biological significance of this genetic variability remains unclear, but this variation could have significant implications for fish health management. The results from this study provide baseline data for future work developing strategies to ameliorate columnaris-related losses in the US Pacific Northwest.In this study, we describe in detail the life cycle of Tachaea chinensis (Isopoda Corallanidae), a branchial ectoparasitic isopod that infests the freshwater shrimp Palaemonetes sinensis in China. We obtained 14 ovigerous T. chinensis females (8.22-11.92 mm in length) and observed the development of embryos through 5 sequential ontogenetic stages within the brood pouches (marsupium) of these females. The number of eggs or mancae (post-larval juveniles) held in the female marsupium ranged from 31 to 86, with a mean ± SD of 61.25 ± 16.16 eggs. Female T. chinensis were semelparous, i.e. individuals died following the release of mancae from the marsupium. Released mancae were non-planktonic and immediately infective to host shrimps. However, only a few mancae successfully established contact with a host, and it is thus assumed that the remainder were predated by shrimp. Attached T. chinensis fed on the host hemolymph, and subsequent to host death, these isopods typically searched for a new host. We also found that T. chinensis exhibits a host preference most mancae attached to P. sinensis rather than to Neocaridina sp. or Macrobrachium nipponense. This study provides valuable empirical data that will support future research on the prevention and control of parasitic isopod infections.Complex interactions among hosts, pathogens, and the environment affect the vulnerability of amphibians to the emergence of infectious diseases such as chytridiomycosis, caused by Batrachochytrium dendrobatidis (Bd). Boana curupi is a forest-dwelling amphibian endemic to the southern Atlantic Forest of South America, a severely fragmented region. Here, we evaluated whether abiotic factors (including air and water temperature, relative air humidity, and landscape) are correlated with chytrid infection intensity and prevalence in B. curupi. We found individuals infected with Bd in all populations sampled. Prevalence ranged from 25-86%, and the infection burden ranged from 1 to over 130000 zoospore genomic equivalents (g.e.) (mean ± SD 4913 ± 18081 g.e.). The infection load differed among populations and was influenced by forest cover at scales of 100, 500, and 1000 m, with the highest infection rates recorded in areas with a higher proportion of forest cover. Our results suggest that the fungus is widely distributed in the populations of B. curupi in southern Brazil. Population and disease monitoring are necessary to better understand the relationships between host, pathogen, and environment, especially when, as in the case of B. curupi, threatened species are involved.Preliminary evidence suggests that Chinook salmon Oncorhynchus tshawytscha from the Yukon River may be more susceptible to Ichthyophonus sp. infections than Chinook from stocks further south. To investigate this hypothesis in a controlled environment, we experimentally challenged juvenile Chinook from the Yukon River and from the Salish Sea with Ichthyophonus sp. and evaluated mortality, infection prevalence and infection load over time. We found that juvenile Chinook salmon from a Yukon River stock were more susceptible to ichthyophoniasis than were those from a Salish Sea stock. After feeding with tissues from infected Pacific herring Clupea pallasii, Chinook salmon from both stocks became infected. The infection was persistent and progressive in Yukon River stock fish, where infections sometimes progressed to mortality, and histological examinations revealed parasite dissemination and proliferation throughout the host tissues. In Salish Sea-origin fish, however, infections were largely transient; host mortalities were rare, and parasite stages were largely cleared from most tissues after 3-4 wk. Susceptibility differences were evidenced by greater cumulative mortality, infection prevalence, parasite density, proportion of fish demonstrating a cellular response, and intensity of the cellular response among fish from the Yukon River stock. These observed differences between Chinook salmon stocks were consistent when parasite exposures occurred in both freshwater and seawater. These results support the hypothesis that a longer-standing host-pathogen relationship, resulting in decreased disease susceptibility, exists among Salish Sea Chinook salmon than among Yukon River conspecifics.For more than a century, the scientific consensus stated that a nucleus from a terminally differentiated cell would not be able to control the development of offspring. This theory was refuted by the birth of Dolly, the first animal generated by nuclear transfer using an adult somatic cell as a nuclear donor. Following this paradigm shift, a wide variety of animals has been cloned using somatic cell nuclear transfer. Coupled with https://www.selleckchem.com/products/sacituzumab-govitecan.html , somatic cell nuclear transfer has become the method of choice for the generation of genetically modified farm animals. #link# This has opened new opportunities to study the function of genes and has led to the establishment of animal models for a variety of human conditions and diseases or to improve the health of livestock animals.Obesity is a chronic disease that impairs female reproduction. When gestation is achieved, maternal obesity can cause offspring's health complications. We intended to evaluate the effects of maternal pre-conceptional obesity on uterine contractile activity, embryo implantation and offspring development. Using cafeteria diet-induced obesity as an animal model, we found that maternal obesity delays embryo transport from the oviduct to the uterus and alters the intrauterine embryo positioning. Adrenergic receptor (AR) signaling is involved in embryo positioning, so all AR isoforms were screened in the pre-implantation uteri. We found that the β2AR is the dominant isoform in the rat uteri and that obesity causes its upregulation. Although β2AR activation is known to induce uterine relaxation, higher spontaneous contractile activity was detected in obese dams. Uteri from obese dams showed a higher sensitivity to salbutamol (a selective agonist of β2AR) than controls, consistent with the higher β2AR levels detected in those animals.
Six isolates (12.2%, n = 6/49) were identified as GG3, which were cultured from rainbow trout (n = 3) and steelhead trout (n = 3). Two isolates were identified as GG2 (4.1%, n = 2/49) and were from ornamental fish. No GG4 isolates were cultured in this study. The biological significance of this genetic variability remains unclear, but this variation could have significant implications for fish health management. The results from this study provide baseline data for future work developing strategies to ameliorate columnaris-related losses in the US Pacific Northwest.In this study, we describe in detail the life cycle of Tachaea chinensis (Isopoda Corallanidae), a branchial ectoparasitic isopod that infests the freshwater shrimp Palaemonetes sinensis in China. We obtained 14 ovigerous T. chinensis females (8.22-11.92 mm in length) and observed the development of embryos through 5 sequential ontogenetic stages within the brood pouches (marsupium) of these females. The number of eggs or mancae (post-larval juveniles) held in the female marsupium ranged from 31 to 86, with a mean ± SD of 61.25 ± 16.16 eggs. Female T. chinensis were semelparous, i.e. individuals died following the release of mancae from the marsupium. Released mancae were non-planktonic and immediately infective to host shrimps. However, only a few mancae successfully established contact with a host, and it is thus assumed that the remainder were predated by shrimp. Attached T. chinensis fed on the host hemolymph, and subsequent to host death, these isopods typically searched for a new host. We also found that T. chinensis exhibits a host preference most mancae attached to P. sinensis rather than to Neocaridina sp. or Macrobrachium nipponense. This study provides valuable empirical data that will support future research on the prevention and control of parasitic isopod infections.Complex interactions among hosts, pathogens, and the environment affect the vulnerability of amphibians to the emergence of infectious diseases such as chytridiomycosis, caused by Batrachochytrium dendrobatidis (Bd). Boana curupi is a forest-dwelling amphibian endemic to the southern Atlantic Forest of South America, a severely fragmented region. Here, we evaluated whether abiotic factors (including air and water temperature, relative air humidity, and landscape) are correlated with chytrid infection intensity and prevalence in B. curupi. We found individuals infected with Bd in all populations sampled. Prevalence ranged from 25-86%, and the infection burden ranged from 1 to over 130000 zoospore genomic equivalents (g.e.) (mean ± SD 4913 ± 18081 g.e.). The infection load differed among populations and was influenced by forest cover at scales of 100, 500, and 1000 m, with the highest infection rates recorded in areas with a higher proportion of forest cover. Our results suggest that the fungus is widely distributed in the populations of B. curupi in southern Brazil. Population and disease monitoring are necessary to better understand the relationships between host, pathogen, and environment, especially when, as in the case of B. curupi, threatened species are involved.Preliminary evidence suggests that Chinook salmon Oncorhynchus tshawytscha from the Yukon River may be more susceptible to Ichthyophonus sp. infections than Chinook from stocks further south. To investigate this hypothesis in a controlled environment, we experimentally challenged juvenile Chinook from the Yukon River and from the Salish Sea with Ichthyophonus sp. and evaluated mortality, infection prevalence and infection load over time. We found that juvenile Chinook salmon from a Yukon River stock were more susceptible to ichthyophoniasis than were those from a Salish Sea stock. After feeding with tissues from infected Pacific herring Clupea pallasii, Chinook salmon from both stocks became infected. The infection was persistent and progressive in Yukon River stock fish, where infections sometimes progressed to mortality, and histological examinations revealed parasite dissemination and proliferation throughout the host tissues. In Salish Sea-origin fish, however, infections were largely transient; host mortalities were rare, and parasite stages were largely cleared from most tissues after 3-4 wk. Susceptibility differences were evidenced by greater cumulative mortality, infection prevalence, parasite density, proportion of fish demonstrating a cellular response, and intensity of the cellular response among fish from the Yukon River stock. These observed differences between Chinook salmon stocks were consistent when parasite exposures occurred in both freshwater and seawater. These results support the hypothesis that a longer-standing host-pathogen relationship, resulting in decreased disease susceptibility, exists among Salish Sea Chinook salmon than among Yukon River conspecifics.For more than a century, the scientific consensus stated that a nucleus from a terminally differentiated cell would not be able to control the development of offspring. This theory was refuted by the birth of Dolly, the first animal generated by nuclear transfer using an adult somatic cell as a nuclear donor. Following this paradigm shift, a wide variety of animals has been cloned using somatic cell nuclear transfer. Coupled with https://www.selleckchem.com/products/sacituzumab-govitecan.html , somatic cell nuclear transfer has become the method of choice for the generation of genetically modified farm animals. #link# This has opened new opportunities to study the function of genes and has led to the establishment of animal models for a variety of human conditions and diseases or to improve the health of livestock animals.Obesity is a chronic disease that impairs female reproduction. When gestation is achieved, maternal obesity can cause offspring's health complications. We intended to evaluate the effects of maternal pre-conceptional obesity on uterine contractile activity, embryo implantation and offspring development. Using cafeteria diet-induced obesity as an animal model, we found that maternal obesity delays embryo transport from the oviduct to the uterus and alters the intrauterine embryo positioning. Adrenergic receptor (AR) signaling is involved in embryo positioning, so all AR isoforms were screened in the pre-implantation uteri. We found that the β2AR is the dominant isoform in the rat uteri and that obesity causes its upregulation. Although β2AR activation is known to induce uterine relaxation, higher spontaneous contractile activity was detected in obese dams. Uteri from obese dams showed a higher sensitivity to salbutamol (a selective agonist of β2AR) than controls, consistent with the higher β2AR levels detected in those animals.
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