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Canine systemic protothecosis is an uncommon disease caused by Prototheca spp., which are saprophytic algae occurring ubiquitously in nature. Infection occurs most commonly in immunocompromised animals. Most infected dogs have chronic large-bowel diarrhea, ocular lesions, neurologic deficits, or a combination thereof, but various tissues can be affected. This case highlights a unique presentation of protothecosis in a dog, in which lameness resulting from osteomyelitis was the predominant clinical sign. Key clinical message: Although osteomyelitis is an atypical manifestation, protothecosis can be a differential diagnosis for an aggressive bony lesion and is particularly worthy of consideration in immunocompromised dogs., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Background: Protothecosis in dogs is a rare, yet emerging disease, distinguished by its often-aggressive clinical course and high fatality rate. Our study was conducted to enhance treatment protocols for affected dogs by better understanding the genetic diversity and drug resistance patterns of Prototheca species., Objectives: To identify species and drug susceptibility profiles of an international collection of 28 Prototheca strains isolated from cases of protothecosis in dogs., Animals: None., Methods: Retrospective study. Species-level identification was made for isolates from 28 dogs in 6 countries by molecular typing with the partial cytb gene as a marker. For the determination of minimum inhibitory concentrations (MICs) and minimum algicidal concentrations (MACs), the Clinical Laboratory Standards Institute (CLSI) protocol (M27-A3) was used., Results: Prototheca bovis was the most prevalent species, accounting for 75% (21/28) of the cases, followed by P. wickerhamii (18%; 5/28) and P. ciferrii (7%; 2/28). Of the 6 drugs tested, efinaconazole (EFZ) was the most potent in vitro, with its median MIC and MAC values equal to 0.125 mg/L. The lowest activity was found for fluconazole (FLU), with MIC and MAC medians of 48 mg/L and 64 mg/L, respectively., Conclusions and Clinical Importance: Our study identifies P. bovis as the species that most frequently causes protothecosis in dogs, which suggests the possibility of cross-species infection from other animals, especially cows. Additionally, it indicates that EFZ could be used in the treatment of infection in the colon., (© 2024 The Author(s). Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Protothecosis is an infectious disease caused by unicellular algae of the genus Prototheca, which are mainly known for causing mastitis in farm animals. However, there are reports of protothecosis in humans and other animals, such as dogs and cats, which develop cutaneous lesions or systemic lesions. Dogs with the systemic form generally develop bloody diarrhoea and blindness and neurological signs may also occur. The condition generally leads to the animal being euthanized due to the unfavourable prognosis. The objective of this work was to report two cases of disseminated protothecosis, one in a Pekingese dog (case 1) and the other in a German Shepherd Dog (case 2). Both animals had a history of chronic diarrhoea with haematochezia, which was unresponsive to various treatments in case 2. Both dogs were euthanized due to their clinical condition and were sent to the Veterinary Pathology Laboratory of the Federal University of Paraná for post-mortem examination. Macroscopically, the lesions in both cases were similar and were characterized by multifocal millimetre-sized white nodulations in the heart, skeletal muscles and intestinal serosa, as well as signs of fibrinonecrotic enterocolitis and lymphoplasmacytic interstitial nephritis. In both cases there was also retinal displacement with lymphoplasmacytic uveitis and chorioretinitis. The cytological and histopathological evaluation of the tissues revealed the presence of structures compatible with Prototheca spp. Polymerase chain reaction identified Prototheca bovis in both cases. This is a rarely reported disease and must be considered as a differential diagnosis in cases of chronic diarrhoea with haematochezia that progress to blindness in dogs., Competing Interests: Declaration of competing interests The authors declared no conflicts of interest in relation to the research, authorship or publication of this article., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Case Histories: Medical records of four dogs diagnosed with protothecosis in New Zealand were reviewed. The dogs were aged between 4 and 9 years and three of the four dogs were female. Breeds were one Labrador, one Miniature Schnauzer and two crossbreeds. The reasons for initial veterinary evaluation were a cough and opaque appearance of the right eye (Case 1), diarrhoea (Cases 2 and 3), and cutaneous disease (Case 4)., Clinical Findings: The ocular signs were characterised by panuveitis, retinal detachment and secondary glaucoma. Gastrointestinal signs included chronic haemorrhagic diarrhoea due to colitis. Three cases had disseminated infection and developed both bilateral, blinding, ocular disease and chronic gastrointestinal disease. Cutaneous signs consisted of draining fistulae over the olecranon, multifocal cutaneous nodules, and ulceration and tracts of the foot pads. Disseminated protothecosis was confirmed by histopathology of biopsied ocular tissues in Cases 1 and 2 and by gastrointestinal biopsies in Case 3. Prototheca spp. were also identified in cytological specimens from Cases 1 and 4 and recovered by culture in Cases 2 and 4. Cutaneous protothecosis was diagnosed in Case 4 initially by cytology and histopathology of skin lesions, and Prototheca zopfii was confirmed by PCR of cultured organisms., Treatment and Outcome: Prior to diagnosis of protothecosis, a variety of treatments were prescribed to treat the gastrointestinal and ocular signs. After diagnosis, only Cases 2 and 4 received medication aimed at treating the protothecal infection, which was itraconazole in both cases. Following the progression of clinical signs and concerns about quality of life, all four dogs were euthanised., Diagnosis: Disseminated protothecosis in three dogs, cutaneous protothecosis in one dog., Clinical Relevance: Canine protothecosis is rarely reported, despite the ubiquity of the causal algae, and the disease usually carries an extremely grave prognosis when infection is generalised. In New Zealand, protothecosis should be considered as a differential diagnosis in dogs with panuveitis, chorioretinitis or retinal detachment, colitis, or nodular, ulcerative or fistulating cutaneous lesions.

Background: Protothecosis is a rare infectious disease caused by unicellular, achlorophyllous, microalgae of the genus Prototheca, ubiquitously distributed in nature. The algae are emerging pathogens, whose incidence is increasing in both human and animal populations and serious systemic infections related to this pathogen have been increasingly described in humans in recent years. After mastitis in dairy cows, canine protothecosis is the second most prevalent form of the protothecal disease in animals. Here, we report the first case of chronic cutaneous protothecosis due to P. wickerhamii in a dog in Brazil, successfully treated with a long-term therapy with itraconazole in pulse., Case Presentation: Upon clinical examination, exudative nasolabial plaque, ulcered, and painful lesions in central and digital pads and lymphadenitis were observed in a 2-year-old mixed-breed dog, with a 4-month history of cutaneous lesions and contact with sewage water. Histopathological examination revealed intense inflammatory reaction, with numerous spherical to oval, encapsulated structures stained with Periodic Acid Schiff, compatible with Prototheca morphology. Tissue culture on Sabouraud agar revealed yeast-like, greyish-white colonies after 48 h of incubation. The isolate was subjected to mass spectrometry profiling and PCR-sequencing of the mitochondrial cytochrome b (CYTB) gene marker, leading to identification of the pathogen as P. wickerhamii. The dog was initially treated with oral itraconazole at a dosage of 10 mg/kg once daily. After six months, the lesions resolved completely, yet recurred shortly after cessation of therapy. The dog was then treated with terbinafine at a dose of 30 mg/kg, once daily for 3 months, with no success. The resolution of clinical signs, with no recurrence over a 36-months follow-up period, was achieved after 3 months of treatment with itraconazole (20 mg/kg) in pulse intermittently on two consecutive days a week., Conclusions: This report highlights the refractoriness of skin infections by Prototheca wickerhamii with therapies proposed in the literature and suggests a new treatment option with oral itraconazole in pulse dosing for long-term disease control successfully performed in a dog with skin lesions., (© 2023. The Author(s).)

A controlled Saprolegnia parasitica infection model was used to challenge 1158 fish representing 105 pedigreed Atlantic salmon families to evaluate the possibility of selecting for Saprolegnia resistance in a commercial breeding programme. Fish were infected in five study tanks and observed for 40 days post-infection for lesion score and survival. Survival analysis of the top 10 resistant and bottom 10 susceptible families indicated that the hazard of dying following Saprolegnia infection was 1509% higher in susceptible families. In all fish, a 10 g increase in weight correlated with a 7.8% increase in the hazard of dying while sex did not affect mortality. Resistance to Saprolegnia was estimated to have a heritability of 0.25, indicating that selection is possible. Genetic and phenotypic correlations indicated that the 11-point scoring system, developed in this study to quantify Saprolegnia infection severity, had a high negative correlation with survival as days to mortality at ≥-0.922(±0.005), suggesting that the scoring method could help assess lesion development in studies where mortality is not the primary biological endpoint., (© 2022 The Authors. Journal of Fish Diseases published by John Wiley & Sons Ltd.)

Case History: A 1-year-old Border Terrier presented with acute onset of neurological signs and neck pain., Clinical Findings: Severe generalised ataxia, muscle tremors and cranial nerve deficits were noted. Multifocal brain lesions were suspected based on neurological examination. Computed tomography revealed an abdominal mass and cerebellar herniation through the foramen magnum., Laboratory and Pathological Findings: Cytological and histopathological analysis of the abdominal mass revealed necrotising and granulomatous lymphadenitis with intralesional algal elements most consistent with Prototheca spp.. Culture of a sample from the mesenteric lymph node confirmed the presence of Prototheca spp. which was identified as P. bovis based on sequencing of a DNA fragment amplified by PCR. Following inadequate response to symptomatic therapy and poor prognosis, the dog was subjected to euthanasia. Histopathological evaluation of the central nervous system lesions, identified granulomatous meningitis and ventriculitis with the presence of intralesional algae., Diagnosis: Disseminated protothecosis with granulomatous meningitis and ventriculitis caused by Prototheca bovis (formerly P. zopfii gen. 2)., Clinical Relevance: This is the first case report of disseminated protothecosis with central nervous system involvement in a dog in New Zealand.

Protothecosis, an infectious disease caused by the green algae Prototheca zopfii and P. wickerhamii , occurs sporadically in domestic animals and humans. Diagnosis of CNS protothecosis is based on neurologic signs that indicate multifocal nervous system lesions and that follow a period of chronic diarrhea and weight loss, cytologic observation of algae in fecal culture or histopathology, and detection of the agent by PCR assay of infected tissues. Here, we report a case of a paraparetic dog with CNS protothecosis that was diagnosed definitively antemortem using CSF cytology, PCR, and DNA sequencing. A 4-y-old mixed-breed dog developed progressive paraparesis that followed weight loss and diarrhea. CSF analysis revealed marked eosinophilic pleocytosis. Prototheca organisms were detected by microscopic examination of the CSF, and speciated as P. zopfii by CSF PCR and DNA sequencing. Other possible causes of paraparesis were ruled out using computed tomography, serology, and CSF PCR. The dog's condition deteriorated despite treatment, developing forebrain and central vestibular system clinical signs, and it was euthanized at the owner's request. Postmortem examination was declined. Our findings indicate that when CNS protothecosis is suspected, antemortem diagnosis can be made using CSF analysis and a PCR assay.

The effect of cinnamaldehyde (CM) enriched diet on immunity and cytokine gene expression in Channa striatus against Aphanomyces invadans is reported. C. striatus was uniformly divided into eight groups (n = 25 fish each) and fed with formulated diets with 0, 5, 10, and 15 mg kg -1  CM enriched diet. In healthy and infected groups fed with 5 mg kg -1 diet the leukocytes count increased significantly after 4th week; with 10 mg kg -1  CM diet the increase manifested after 6th week, but with 15 mg kg -1 not even after 8th week. In both groups, 5 mg kg -1  CM diet resulted in a significant increase in the serum total protein, albumin, and globulin levels after 4th week, whereas with other diets this effect was observed only after 6th week. Similarly, with any enriched diet the lysozyme activity increased significantly, but with 15 mg kg -1  CM diet only after 6th week. In both groups the complement activity and lymphocyte production increased significantly when fed with 5 mg kg -1  CM diet after 4th week while with other enriched diets only after 6th week. The phagocytic activity increased significantly in both groups fed with 5 mg kg -1  CM diet after 6th week, whereas the SOD activity increased after 4th week. The IgM production increased significantly in both groups fed with 5 mg kg -1  CM diet after 2nd week, while with 5 and 10 mg kg -1  CM diet after 4th week. In both groups, the expression of CXCR3α was significant on 4th week when fed with 10 mg kg -1  CM diet, while in the healthy group fed with 15 mg kg -1  CM diet the expression manifested earlier than 4th week. However, when fed with 10 and 15 mg kg -1  CM diets the increase was observed on 6th week; whereas, the expression of MHC-I reached the maximum on 6th week with any enriched diet. The results indicate that in C. striatus the innate immunity and expression of cytokine and immune related genes were significantly modulated when fed with 5 mg kg -1  CM diet on 4th week against A. invadans., (Crown Copyright © 2021. Published by Elsevier Ltd. All rights reserved.)

The oomycete pathogen Aphanomyces astaci , also known as "crayfish plague", is an obligate fungal-like parasite of freshwater crustaceans and is considered responsible for the ongoing decline of native European crayfish populations. A. astaci is thought to secrete a wide array of effectors and enzymes that facilitate infection, however their molecular mechanisms have been poorly characterized. Here, we report the identification of AA15 lytic polysaccharide monooxygenases (LPMOs) as a new group of secreted virulence factors in A. astaci . We show that this enzyme family has greatly expanded in A. astaci compared to all other oomycetes, and that it may facilitate infection through oxidative degradation of crystalline chitin, the most abundant polysaccharide found in the crustacean exoskeleton. These findings reveal new roles for LPMOs in animal-pathogen interactions, and could help inform future strategies for the protection of farmed and endangered species.

Understanding the ways in which pathogens infect host cells is essential to improve and develop new treatment strategies. This study aimed to generate a novel in vitro infection model by establishing a reproducible 3D spheroid cell culture system that may lead to a reduced need for animals in fish disease research. 2D models (commonly cell lines) cannot replicate many key conditions of in vivo infections, but 3D spheroids have the potential to provide bridging technology between in vivo and in vitro systems. 3D spheroids were generated using cells from rainbow trout (Oncorhynchus mykiss) cell lines, RTG-2 and RTS-11. The RTG-2 spheroids were tested for their potential to be infected upon exposure to Saprolegnia parasitica spores. Positive infiltration of mycelia into the spheroids was verified by confocal microscopy. As a closer analogue of in vivo conditions encountered during infection, the straightforward model developed in this study shows promise as an additional tool that can be used to further our understanding of host-pathogen interactions for Saprolegnia and possibly a variety of other fish pathogens., (© 2021 John Wiley & Sons Ltd.)

Freshwater crayfish immunity has received great attention due to the need for urgent conservation. This concern has increased the understanding of the cellular and humoral defense systems, although the regulatory mechanisms involved in these processes need updating. There are, however, aspects of the immune response that require clarification and integration. The particular issues addressed in this review include an overall description of the oomycete Aphanomyces astaci , the causative agent of the pandemic plague disease, which affects freshwater crayfish, and an overview of crustaceans' immunity with a focus on freshwater crayfish. It includes a classification system of hemocyte sub-types, the molecular factors involved in hematopoiesis and the differential role of the hemocyte subpopulations in cell-mediated responses, including hemocyte infiltration, inflammation, encapsulation and the link with the extracellular trap cell death pathway (ETosis). In addition, other topics discussed include the identity and functions of hyaline cells, the generation of neoplasia, and the emerging topic of the role of sessile hemocytes in peripheral immunity. Finally, attention is paid to the molecular execution of the immune response, from recognition by the pattern recognition receptors (PRRs), the role of the signaling network in propagating and maintaining the immune signals, to the effector elements such as the putative function of the Down syndrome adhesion molecules (Dscam) in innate immune memory., Competing Interests: The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Bouallegui.)

Interferons (IFNs) are cytokines that play an important role in the immune response of animals and humans. A number of studies reviewed here have evaluated the use of human, canine and feline IFNs as treatments for infectious, inflammatory and neoplastic disease in dogs and cats. Recombinant canine IFN-γ is deemed an efficacious therapy for canine atopic dermatitis. Recombinant feline IFN-ω is effective against canine parvoviral enteritis and has also been recommended for canine atopic dermatitis. Based on limited evidence, recombinant canine IFN-α could be a topical treatment option for dogs with gingivitis and keratoconjunctivitis sicca. Conclusive evidence is lacking for other diseases and large randomised controlled trials are needed before IFNs can be recommended for other indications., (Copyright © 2021. Published by Elsevier Ltd.)

Porcine ear necrosis (PEN) is a condition that mainly occurs in intensive pig production systems and mostly affects piglets after weaning. The syndrome manifests itself with lesions on the pinna, which can heal or become more severe resulting in partial loss of the ear. The pathogenesis of the condition is not fully known. Three different hypotheses for the development of PEN are described in this review: (1) damage of the epidermis due to Staphylococcal exfoliative toxins; (2) occlusion of small blood vessels; and (3) ear biting with subsequent β-hemolytic streptococcal infection. Risk factors have not been completely elucidated, but viral and bacterial infections, and husbandry factors such as environment, housing conditions and management, have been suggested. It is also possible that some cases are due to a combination of these factors. The role of parasitic infestations has been not investigated. Due to bacterial involvement, severely affected pigs can be treated with antimicrobials. Control and preventive measures should focus on reducing potential risk factors by implementing herd immunization, as well as improvement of sanitary conditions, feed quality (with respect to mycotoxin contamination), management (appropriate stocking density), and environmental conditions (e.g. number of drinkers and feeders and/or optimal ventilation). Further research is needed to better understand the precise etiology and pathogenesis of PEN, so that risk factors can be identified and more targeted control measures can be implemented., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The presence of many pathogens varies in a predictable manner with latitude, with infections decreasing from the equator towards the poles. We investigated the geographic trends of pathogens infecting a widely distributed carnivore: the gray wolf (Canis lupus). Specifically, we investigated which variables best explain and predict geographic trends in seroprevalence across North American wolf populations and the implications of the underlying mechanisms. We compiled a large serological dataset of nearly 2000 wolves from 17 study areas, spanning 80° longitude and 50° latitude. Generalized linear mixed models were constructed to predict the probability of seropositivity of four important pathogens: canine adenovirus, herpesvirus, parvovirus, and distemper virus-and two parasites: Neospora caninum and Toxoplasma gondii. Canine adenovirus and herpesvirus were the most widely distributed pathogens, whereas N. caninum was relatively uncommon. Canine parvovirus and distemper had high annual variation, with western populations experiencing more frequent outbreaks than eastern populations. Seroprevalence of all infections increased as wolves aged, and denser wolf populations had a greater risk of exposure. Probability of exposure was positively correlated with human density, suggesting that dogs and synanthropic animals may be important pathogen reservoirs. Pathogen exposure did not appear to follow a latitudinal gradient, with the exception of N. caninum. Instead, clustered study areas were more similar: wolves from the Great Lakes region had lower odds of exposure to the viruses, but higher odds of exposure to N. caninum and T. gondii; the opposite was true for wolves from the central Rocky Mountains. Overall, mechanistic predictors were more informative of seroprevalence trends than latitude and longitude. Individual host characteristics as well as inherent features of ecosystems determined pathogen exposure risk on a large scale. This work emphasizes the importance of biogeographic wildlife surveillance, and we expound upon avenues of future research of cross-species transmission, spillover, and spatial variation in pathogen infection.

Rapid expansion of salmon aquaculture has resulted in high-density populations that host diverse infectious agents, for which surveillance and monitoring are critical to disease management. Screening can reveal infection diversity from which disease arises, differential patterns of infection in live and dead fish that are difficult to collect in wild populations, and potential risks associated with agent transmission between wild and farmed hosts. We report results from a multi-year infectious-agent screening program of farmed salmon in British Columbia, Canada, using quantitative PCR to assess presence and load of 58 infective agents (viruses, bacteria, and eukaryotes) in 2931 Atlantic salmon (Salmo salar). Our analysis reveals temporal trends, agent correlations within hosts, and agent-associated mortality signatures. Multiple agents, most notably Tenacibaculum maritimum, were elevated in dead and dying salmon. We also report detections of agents only recently shown to infect farmed salmon in BC (Atlantic salmon calicivirus, Cutthroat trout virus-2), detection in freshwater hatcheries of two marine agents (Kudoa thyrsites and Tenacibaculum maritimum), and detection in the ocean of a freshwater agent (Flavobacterium psychrophilum). Our results provide information for farm managers, regulators, and conservationists, and enable further work to explore patterns of multi-agent infection and farm/wild transmission risk.

This study assessed the impact of routine vaccination of Atlantic salmon pre-smolts on gene expression and the possible link to saprolegniosis on Scottish fish farms. Fish were in 4 different groups 1) 'control' - fish without handling or vaccination 2) 'vaccinated' - fish undergoing full vaccination procedure 3) 'non vaccinated' - fish undergoing full vaccination procedure but not vaccinated and 4) 'vaccinated-MH' - fish undergoing vaccination, but procedure involved minimal handling. A strong increase in cortisol and glucose levels was observed after 1 h in all groups relative to the control group. Only in the non-vaccinated group did the level decrease to near control levels by 4 h. Expression levels of six stress marker genes in general for all groups showed down regulation over a 9-day sampling period. In contrast, expression levels for immune response genes in the head kidney showed significant up-regulation for all eight genes tested for both vaccinated groups whereas the non-vaccinated group showed up-regulation for only MHC-II and IL-6b in comparison to the control. Both the vaccination procedure and the administration of the vaccine itself were factors mediating changes in gene expression consistent with fish being susceptible to natural occurring saprolegniosis following vaccination., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Encephalomyocarditis virus (EMCV) infection was detected by real-time reverse transcription PCR (qRT-PCR) in four adult alpacas (Vicugna pacos) from two properties on the Far North Coast of New South Wales (NSW) in April and May 2018 and in two adult alpacas from a third property on the Central Coast of NSW in October 2018. Viral RNA was detected in a range of samples, including blood, fresh body organs and mucosal swabs. EMCV was isolated from the blood and body organs of five of these alpacas. These animals displayed a range of clinical signs, including inappetence, colic, recumbency and death. Necropsy findings included multifocal to coalescing areas of myocardial pallor, pulmonary congestion and oedema, hepatic congestion and serosal effusion. Histopathological changes comprised acute, multifocal myocardial degeneration and necrosis, with mild, neutrophilic and lymphocytic inflammation (5/5 hearts) and mild, perivascular neutrophilic meningoencephalitis (1/3 brains). This is the first report of disease due to EMCV in alpacas under farm conditions, and it identifies EMCV infection as a differential diagnosis for acute disease and death in this camelid species. In addition to the samples traditionally preferred for EMCV isolation (fresh heart, brain and spleen), blood samples are also appropriate for EMCV detection by qRT-PCR assay., (© 2020 Australian Veterinary Association.)

A 10-month-old male Rhodesian Ridgeback was presented to the Clinic of Small Animal Medicine, LMU, Germany, with a 6-month history of chronic diarrhea and hematochezia. The dog lived in Germany and had never traveled abroad. Complete blood count and serum biochemistry performed by the referring veterinarian revealed neutrophilia, hyperkalemia, and hyponatremia, with a basal cortisol of 4.3 µg/dl, which excluded hypoadrenocorticism. Since antibiotic treatment had not resulted in any improvement, a 2 week course of prednisolone administration had been initiated, leading to a marked deterioration of intestinal signs and a significant weight loss of 6 kg. At the time of referral, the patient was markedly emaciated, dehydrated, hypovolemic and had a rectal temperature of 39.6 °C. Abdominal ultrasound showed a thickened and irregular colonic wall. On colonoscopy, an irregular colonic mucosa with ulcerations was observed. Histopathologic examination revealed an ulcerative granulomatous colitis, and on Periodic acid-Schiff reaction (PAS) numerous organisms consistent with Prototheca spp. were identified. Prototheca zopfii infection was confirmed by culture and MALDI-TOF MS. In order to test for an underlying immunodeficiency, immunoglobulin levels in serum were determined. IgM was decreased, while IgG and IgA levels were within the reference interval. Due to deterioration of general condition, grave prognosis and costs of a treatment trial, the patient was euthanized one week later, and necropsy was performed. Prototheca spp. were detected on histopathologic examination in the lymphnodes, however not in the eyes or the central nervous system. Protothecosis should be considered an differential diagnosis in dogs with chronic diarrhea and ulcerative granulomatous colitis even in dogs living in Germany. Histopathologic examination of colonic biopsies with special stains such as PAS is recommended in every dog with signs of chronic large bowel disease in order to avoid missing this rare infectious disease., Competing Interests: Die Autoren bestätigen, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

The genus Prototheca consists of achlorophyllic algae that are ubiquitous in the environment and animal intestines. However, this organism has forfeited its photosynthetic ability and switched to parasitism. In 1894, Krüger described two microorganisms isolated in Germany from mucous flux of Tilia and Ulmus spp., namely Prototheca moriformis and P. zopfii. Based on their yeast-like colony morphology, Krüger classified these organisms as fungi. The genus is now included within the class Trebouxiophyceae, order Chlorellales, and family Chlorellaceae. Historically, protothecosis and infections caused by green algae have been studied in the field of medical mycology. Prototheca spp. have been found to colonize human skin, fingernails, the respiratory tract, and digestive system. Although human infection by Prototheca is considered rare, an increase in infections has been noted among immunosuppressed patients, those on corticosteroid treatment, or both. Moreover, the first human outbreak of protothecal algaemia and sepsis was recently reported in a tertiary care chemotherapy oncology unit in 2018. Prototheca is also a causative pathogen of bovine disease. Prototheca zopfii and P. blaschkeae are associated with bovine mastitis, which causes a reduction in milk production and secretion of thin, watery milk containing white flakes. Economic losses are incurred either directly via reduced milk production and premature culling of affected animals or indirectly as a result of treatment and veterinary care expenses. Thus, knowledge of this fungal-like pathogen is essential in human and veterinary medicine. In this mini-review, I briefly introduce human and animal protothecoses.

This study was designed to prevent fungal disease (Saprolegnia parasitica) that occurs on rainbow trout eggs (Oncorhynchus mykiss) by using wastes of onion (Allium cepa) and garlic (Allium sativum) plants. For this purpose, fertilized rainbow trout eggs were exposed to garlic skin, garlic stem and onion skin aqueous methanolic extracts by bathing in concentrations of 0.4, 0.8, 1.6 and 3.2 g/L, whereas the control group was left untreated. The larvae in all groups were monitored until they become free-swimming larvae, the number of eggs died due to fungus was recorded, and the data obtained from experimental groups and control group were compared. As a result, it was determined that onion skin had no effect on the number of eggs that died due to fungus (p > .05), while garlic skin and garlic stem extracts significantly reduced the number of fungal infestations without affecting the number of live larvae or the embryological development of the eggs (p < .05). In light of these data, we conclude that garlic skin (0.4, 0.8, and 1.6 g/L) and garlic stem (0.8 and 1.6 g/L) aqueous methanolic extracts are effective at preventing Saprolegnia parasitica infestation on rainbow trout eggs and may be used in aquaculture., (© 2020 John Wiley & Sons Ltd.)

Malacosporeans are a group of endoparasitic cnidarians (Myxozoa) that use freshwater bryozoans and fish as final and intermediate hosts, respectively. The malacosporean Tetracapsuloides bryosalmonae causes proliferative kidney disease (PKD), an emerging disease in aquaculture and wild fish populations, including threatened salmonids in Europe and the USA. Mixed infections of malacosporeans are often encountered, and a monitoring tool for screening of multiple malacosporean species in either their fish or bryozoan hosts is therefore desirable. We describe an inexpensive method that combines PCR amplification of the partial 18S rRNA gene (~260 bp) and a single-step restriction fragment length polymorphism (RFLP) method for identification of 10 malacosporean lineages and species. We demonstrate and test this methodology on a set of DNA extracted from malacosporeans infecting fish kidney and tissues sampled from bryozoan colonies and compare the results with Sanger sequencing of the same parasite DNA isolates. The PCR-RFLP and Sanger sequencing methods agreed in 100% of cases. The PCR-RFLP method offers a number of opportunities, including screening large panels of host tissue samples to gain insights into infection patterns, characterizing mixed infections, and confirming highly pathogenic T. bryosalmonae infections. The method can also be further refined as new sequence data become available for malacosporeans.

Reproduction of Trachurus picturatus off the western Portuguese coast was studied over 1 yr. During histological analyses, the presence of Kudoa sp. was detected in advanced vitellogenic oocytes. Kudoa infections are known to cause economic loss through the induction of post-mortem liquefaction of fish muscles, but ovarian infection as reported in this study will seriously affect the reproductive potential of the species and thus impact fisheries productivity. Only females showed gonad infection which led to total degradation of advanced vitellogenic oocytes. No macroscopic, somatic or condition indices revealed differences between infected and uninfected females, rendering this infection event a concealed suppression of reproduction.

In this study, effects of nettle (Urtica dioica) on growth, immunity, and gene expressions were examined in rainbow trout after an 8-week feeding period. A total of 264 juvenile rainbow trout (10.72 ± 0.55 g) were selected and stocked randomly in 12 aquaria. Nettle powder was added to the fish feed at three doses, 0.5,1 and 1.5% served as treatments. At the end of 8-week feeding period, the fish were exposed to Saprolegnia parasitica for 3 weeks. Results showed that all treatments fed with nettle diets exhibited significant increases in weight gain and SGR, and decreased FCR compared to the control. Feeding the fish with dietary nettle resulted in significant rises in blood indices and non-specific immunity in comparison with the control. Furthermore, fish fed 0.5% of dietary nettle showed significantly increased expressions of TNF-α, IL-1b, IL-6 and IL-8 genes following 8 weeks of feeding. A significant reduction in mortality rate was observed in the fish treated with 0.5% of nettle compared to the control following challenging with S. parasitica. Our observations indicate that the use of 0.5% nettle powder in rainbow trout diet can improve growth and immunity parameters as well as fish resistance against S. parasitica contamination., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Infectious diseases represent an important barrier to sustainable aquaculture development. Rearing density can substantially impact fish productivity, health and welfare in aquaculture, including growth rates, behaviour and, crucially, immune activity. Given the current emphasis on aquaculture diversification, stress-related indicators broadly applicable across species are needed. Utilising an interspecific comparative transcriptomic (RNAseq) approach, we compared gill gene expression responses of Atlantic salmon (Salmo salar) and Nile tilapia (Oreochromis niloticus) to rearing density and Saprolegnia parasitica infection. Salmon reared at high-density showed increased expression of stress-related markers (e.g. c-fos and hsp70), and downregulation of innate immune genes. Upon pathogen challenge, only salmon reared at low density exhibited increased expression of inflammatory interleukins and lymphocyte-related genes. Tilapia immunity, in contrast, was impaired at low-density. Using overlapping gene ontology enrichment and gene ortholog analyses, we found that density-related stress similarly impacted salmon and tilapia in key immune pathways, altering the expression of genes vital to inflammatory and Th 17 responses to pathogen challenge. Given the challenges posed by ectoparasites and gill diseases in fish farms, this study underscores the importance of optimal rearing densities for immunocompetence, particularly for mucosal immunity. Our comparative transcriptomics analyses identified density stress impacted immune markers common across different fish taxa, providing key molecular targets with potential for monitoring and enhancing aquaculture resilience in a wide range of farmed species., (Copyright © 2020. Published by Elsevier Ltd.)

The black carp Mylopharyngodon piceus is one of the culturally important '4 famous domestic fishes' in China. Recently, infectious diseases caused by Aeromonas hydrophila have drastically altered the operation of the black carp farming industry. In the present study, isobaric tags for relative and absolute quantitation (iTRAQ) were combined with mass spectrometry analysis to screen for differentially abundant black carp serum proteins in response to experimentally induced A. hydrophila infection. A total of 86 differentially abundant proteins were quantified at 24 h post-infection, including 78 down-regulated proteins and 8 up-regulated proteins. The down-regulated proteins included complement C1q subcomponent subunit C, complement factor B/C2A, complement factor B/C2B, complement C3-Q1, complement C3, and complement C4-2. Bioinformatic analysis indicated that the differentially abundant proteins were mainly associated with complement and coagulation cascades (27.9%). Moreover, real-time PCR (qPCR) analysis revealed changes in the gene expression of both C3 and B/C2A in blood cells, liver, kidney, gills, and intestines of the black carp infected with A. hydrophila. However, mRNA expression levels did not consistently correlate with the corresponding protein levels. A polyclonal antibody was prepared using a synthetic C3 peptide. Immunofluorescence analysis showed that the expression of C3 in the kidney was increased with A. hydrophila infection. This work provides a useful characterization of the impact of A. hydrophila infection on the complement system of the black carp.

Within human medicine, it is recognized that the pharmacokinetics (PK) of many compounds can be altered by the presence of inflammation or infection. Research into the reason for these changes has identified pathways that can influence drug absorption, clearance, and tissue distribution. In contrast, far less is known about these relationships within the framework of veterinary medicine. Rather, most of the PK data generated in veterinary species employs healthy subjects, raising the question of whether these studies are founded on an assumption that healthy animal PK reflect that of the diseased animal population. Accordingly, there is a need to explore the PK changes that might be overlooked in studies that recruit only healthy animals to assesses drug PK. To meet this objective, we surveyed the published literature for studies focusing on the impact of disease on the dose-exposure relationships in food-producing and companion animal species. We found that, consistent with humans and laboratory species, both up- and downregulation of the various cytochrome isoenzymes and/or transporters have occurred in response to an increase in inflammatory mediators. These findings suggest that, as observed in human medicine, the potential for differences in the drug PK in healthy versus animal patients points to a need for acquiring a greater understanding of these changes and how they may influence the dose-exposure-response relationships of veterinary pharmaceuticals. SIGNIFICANCE STATEMENT: This review delivers a much-needed summary of published information that provides insights into how disease and inflammation can influence the appropriateness of extrapolating laboratory-based dose-exposure-response relationships to what will occur in the actual veterinary patient. As part of this review, we also examine some of the method-associated issues to be considered when assessing the reported nature and magnitude of these changes., (U.S. Government work not protected by U.S. copyright.)

Dietary tryptophan (Trp) is a precursor for serotonin, a neuromediator involved in stress responses. Tryptophan competes with other large neutral amino acids (LNAA: tyrosine, isoleucine, leucine, valine, and phenylalanine) to cross the blood-brain barrier; therefore, the regulation of circulating LNAA can influence Trp availability in the cortex and serotonin biosynthesis. The hypothesis examined in this study was that increased supplementation of dietary Trp and a reduction in LNAA for weaned pigs experimentally infected with enterotoxigenic Escherichia coli (ETEC; F4) will increase Trp availability in plasma and reduce indices of the stress response, which will translate to reduced production losses. At 21 ± 3 d of age (mean ± SEM), 96 male pigs (Large White × Landrace) weighing 6.3 ± 0.98 kg (mean ± SEM) were individually penned and allocated to a 4 × 2 factorial arrangement of treatments, with respective factors being 1) four dietary standardized ileal digestible (SID) Trp and LNAA contents, being HTrpHLNAA (Low Trp-High LNAA; 0.24% SID Trp: 5.4% SID LNAA), HTrpHLNAA (Low Trp-Low LNAA; 0.24% SID Trp: 4.6% SID LNAA), HTrpHLNAA (High Trp-High LNAA; 0.34% SID Trp: 5.4% SID LNAA), and HTrpHLNAA (High Trp-Low LNAA; 0.34% SID Trp: 4.6% SID LNAA), and 2) without/with ETEC infection. Pigs were orally infected with 0.8 mL (3.6 × 109 CFU/mL) ETEC at days 7 and 8 after weaning. Pigs fed diets high in Trp irrespective of the level of LNAA (HTrpHLNAA and HTrpLLNAA) had higher plasma Trp concentrations (P < 0.001) and a Trp:LNAA ratio (P < 0.001) before infection and 6 d after infection. Following infection, noninfected pigs had higher plasma Trp (P = 0.03) and a Trp:LNAA ratio (P = 0.004) compared with pigs infected with ETEC. Plasma cortisol levels after infection were higher in ETEC-infected pigs (P = 0.05) and altering dietary Trp and LNAA concentrations did not influence (P > 0.05) plasma cortisol. Pigs fed diet HTrpLLNAA had higher serum serotonin levels 24 h after infection (P = 0.02) compared with pigs fed diets LTrpLLNAA and HTrpHLNAA. Similarly, pigs fed diet HTrpLLNAA had a higher (P = 0.02) average daily gain during the 3-wk study. Overall, average daily feed intake tended to be higher in pigs fed an HTrpLLNAA diet compared with the other diets (P = 0.08). These results suggest that the increased supplementation of dietary Trp with reduced LNAA increased circulating Trp levels that, in turn, likely caused higher serum serotonin levels, irrespective of infection with ETEC, and improved aspects of post-weaning performance., (© The Author(s) 2020. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Food is the largest expense in fish farms. On the other hand, the fish health and wellbeing are determining factors in aquaculture production where nutrition is a vital process for growing animals. In fact, it is important to remember that digestion and nutrition are crucial for animals' physiology. However, digestion is a very complex process in which food is processed to obtain necessary nutrients and central mechanisms of this process require both endocrine and neuronal regulation. In this context, intestinal motility is essential for the absorption of the nutrients (digestive process determining nutrition). An imbalance in the intestinal motility due to an inadequate diet or an infectious process could result in a lower use of the food and inefficiency in obtaining nutrients from food. Very frequently, farmed fish are infected with different pathogenic microorganism and this situation could alter gastrointestinal physiology and, indirectly reduce fish growth. For these reasons, the present review focuses on analysing how different inflammatory molecules or infections can alter conventional modulators of fish intestinal motility., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The Gulf of Maine northern shrimp Pandalus borealis population once supported a significant commercial winter fishery for the New England states. However, the fishery has been on moratorium since 2014 due to consecutive recruitment failures. The issue of parasite-infected eggs, so-called 'white eggs,' has long been identified for the Gulf of Maine northern shrimp, which makes shrimp eggs nonviable and subsequently hampers the recruitment potential. Furthermore, the proportion of infected females was observed to increase with water temperature. As Gulf of Maine temperatures have been increasing for decades, it is important to re-visit issues related to white eggs to evaluate possible impacts of climate-induced environmental changes on the white egg infection rates. We used biological samples collected by the Northeast Fisheries Science Center in 2012-2016 to evaluate the probability that a female shrimp was infected (Pinf) and the proportion of white eggs in an infected female shrimp (pwe). Although Pinf was high, with an average of 73.81% over the Gulf of Maine, pwe was mostly <5%. The variation in both Pinf and pwe examined in this study was not well explained by environmental factors or female body size. However, the average rates of both Pinf and pwe observed in this study were higher than those observed in the 1960s when the bottom temperatures were cooler. The results can be used to account for egg mortality and provide information on potential impacts of possible climate-induced variability on shrimp population dynamics.

Folate pathways components were demonstrated to be present in RNA-sequencing data obtained from uninfected and pathogen-infected Rhipicephalus ticks. Here, PCR and qPCR allowed the identification of folate-related genes in Rhipicephalus spp. ticks and in the tick cell line IDE8. Genes coding for GTP cyclohydrolase I (gch-I), thymidylate synthase (ts) and 6-pyrovoyltetrahydropterin (ptps) were identified. Differential gene expression was evaluated by qPCR between uninfected and infected samples of four biological systems, showing significant upregulation and largest fold-change for the gch-I gene in the majority of the biological systems, supporting the selection for functional analysis by RNAi silencing. Efficient knockdown of the gch-I gene in uninfected and Ehrlichia canis-infected IDE8 cells showed no detectable impact on the capacity of the bacteria to invade or replicate in the tick cells. Overall, this work demonstrated an increase in the expression of some folate-related genes, though not always statistically significantly, in the presence of infection, suggesting gene expression modulation of these pathways, either as a tick response to an invader or manipulation of the tick cell machinery by the pathogens to their advantage. This discovery points to folate pathways as interesting targets for further studies., (© 2019 Blackwell Verlag GmbH.)

An adult dog was presented for chronic cough and a recent development of ulcerated, erythematous nares with nasal discharge. Cytology of enlarged peripheral lymph nodes revealed many intracellular and extracellular organisms. These round or rarely oval organisms measured approximately 5-9 µm in diameter and frequently contained several globular structures, ranging from deeply basophilic to magenta. A thin, clear halo was present. Smaller 1-2 µm, magenta forms were also observed. Fungal culture yielded small, wet, raised, irregularly shaped, white to pale tan colonies. Microbiologic staining of cultured material revealed features suggestive of algae. Histopathology of the lymph nodes revealed marked granulomatous inflammation with intralesional algal organisms suggestive of Prototheca. Electron microscopic findings were also consistent with protothecosis. Polymerase chain reaction, followed by direct DNA sequencing, identified the organism as Prototheca wickerhamii. A brief literature review discussing protothecosis in veterinary medicine is included., (© 2020 American Society for Veterinary Clinical Pathology.)

Background: The oomycete Lagenidium giganteum forma caninum is an uncommon cause of severe dermal and subcutaneous infections in dogs with possible vascular invasion and other fatal sequelae. Infection within the central nervous system of affected dogs has not been previously reported., Case Description: A 6-year-old spayed female mixed-breed dog was evaluated at a referral institution with a 2-month history of suspected fungal infection in the region of the right mandibular lymph node that was refractory to surgical resection and empiric medical therapy. Physical examination identified a 6-cm fluctuant subcutaneous mass caudoventral to the ramus of the right mandible and a second firm mass in the region of the right caudal maxilla. Lesional punch biopsies were submitted for fungal culture and polymerase chain reaction (PCR), which subsequently identified L. giganteum forma caninum infection. Initial treatment consisted of anti-inflammatory doses of prednisone and hyperbaric oxygen therapy. Four weeks following initial evaluation, the patient was presented with progressive neurological signs consistent with a forebrain lesion. Magnetic resonance imaging revealed soft-tissue, contrast-enhancing lesions ventral to the calvarium adjacent to the site of original surgical resection and throughout the brain. Humane euthanasia was elected, and postmortem examination was consistent with the extension of local disease from the right masseter muscle into the right ventral calvarium. Postmortem DNA sequencing confirmed the identity of the organism as L. giganteum forma caninum ., Conclusion: This is the first reported case of intracranial lagenidiosis in the dog. PCR distinguished this species from other Lagenidium species and from oomycetes of other genera, such as Pythium insidiosum and Paralagenidium karlingii . Regional extension of cutaneous lagenidiosis should therefore be considered in cases with concurrent or spontaneous neurologic disease., Competing Interests: The authors declare that there is no conflict of interest.

Many articles have been published on resistant microorganisms isolated from humans, animals, foods and the environment in Ghana. However, there are no reviews that summarize the information on the isolates and antibiotics tested so far in the country. This literature review was completed through "PubMed" and "Google Scholar" searches. We included publications from the period 1975-2015 with a laboratory-based methodology to determine antibiotic resistance of strains isolated in Ghana. In total, 60 articles were included in the analysis with 10% of the articles carrying out nationwide research on antibiotic resistance. The regions of Ghana with the highest published articles were Greater Accra (40%), Ashanti (21.7%) and Northern Region (10%). Most of the studies (86.7%) were related to isolates collected from human samples followed by environmental (5%), animal (3%) and food samples (2%). Ten different bacteria genera were observed in the studies. The most common was Escherichia coli , followed by Staphylococcus spp., Mycobacterium spp. and Streptococcus spp. The highest mean resistance rate was encountered in Escherichia coli (62.2%) followed by Klebsiella spp . (60.4%) and Pseudomonas spp. (52.1%). High resistance rates have been found in Ghana, however, the data are skewed and some regions of the country have been neglected. There is a need for higher quality research to establish and monitor resistance patterns in Upper West, Brong-Ahafo, Volta and Eastern Regions of Ghana., Competing Interests: The authors declare no competing interests., (© Pilar García-Vello et al.)

Oomycetes are water moulds in the kingdom Protista and are not considered true fungi due to the structural lack of chitin and ergosterol. Many oomycetes are pathogenic, such as Pythium spp., and many fish are prone to Saprolegnia spp. infections, particularly in stressful farming situations. A juvenile American alligator (Alligator mississippiensis) was presented for necropsy examination with white, gelatinous, raised lesions over ulcerated regions of skin on the limbs and tail. The alligator came from a hatchery with age-divided enclosures, and several of the animals within the same enclosure showed similar lesions. Numerous hyphae with non-parallel walls and sparse, non-dichotomous branching were observed histologically on Gomori's methenamine silver staining within the ulcers. Although no organisms were detectable via polymerase chain reaction testing of fresh or formalin-fixed tissues, the organism was cultured and sequenced as an Achlya sp., an infrequently identified oomycete. To the author's knowledge, this is the first description of an oomycete infection within the class Reptilia., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Infectious disease is a major cause of mortality for sea otters Enhydra lutris, a keystone species of continued concern for conservationists. Parasitic infection has long been identified as a cause of mortality in otters in both Alaska and California, USA. Corynosoma enhydri (Acanthocephala) is the only parasite that uses sea otters as its primary definitive host and is highly prevalent in otter populations; however, it is generally considered unimportant both pathologically and ecologically, although this assumption is based on limited empirical knowledge. Research has instead focused on Profilicollis infections (P. major, P. kenti, P. altmani) as a significant source of otter mortality due to associated enteritis and peritonitis, which are threats to otter health. Here we describe acanthocephalan infections in sea otters by Profilicollis spp. and C. enhydri, from a survey comparing C. enhydri infections between northern sea otters E. lutris kenyoni (n = 12) and southern sea otters E. lutris nereis (n = 19). We report a novel infection of C. enhydri in a pup approximately 1 mo of age, which shows that the early introduction to solid food at around 3 wk by their mothers may lead to subsequent infection via infected prey items. We also document the first 2 known cases of Profilicollis infection in northern sea otters, which may present an unknown threat to the Alaskan population, or may be an interesting example of accidental infection.

Background: Behavior reflects an organism's health status. Many organisms display a generalized suite of behaviors that indicate infection or predict infection susceptibility. We apply this concept to honey bee aggression, a behavior that has been associated with positive health outcomes in previous studies. We sequenced the transcriptomes of the brain, fat body, and midgut of adult sibling worker bees who developed as pre-adults in relatively high versus low aggression colonies. Previous studies showed that this pre-adult experience impacts both aggressive behavior and resilience to pesticides. We performed enrichment analyses on differentially expressed genes to determine whether variation in aggression resembles the molecular response to infection. We further assessed whether the transcriptomic signature of aggression in the brain is similar to the neuromolecular response to acute predator threat, exposure to a high-aggression environment as an adult, or adult behavioral maturation., Results: Across all three tissues assessed, genes that are differentially expressed as a function of aggression significantly overlap with genes whose expression is modulated by a variety of pathogens and parasitic feeding. In the fat body, and to some degree the midgut, our data specifically support the hypothesis that low aggression resembles a diseased or parasitized state. However, we find little evidence of active infection in individuals from the low aggression group. We also find little evidence that the brain molecular signature of aggression is enriched for genes modulated by social cues that induce aggression in adults. However, we do find evidence that genes associated with adult behavioral maturation are enriched in our brain samples., Conclusions: Results support the hypothesis that low aggression resembles a molecular state of infection. This pattern is most robust in the peripheral fat body, an immune responsive tissue in the honey bee. We find no evidence of acute infection in bees from the low aggression group, suggesting the physiological state characterizing low aggression may instead predispose bees to negative health outcomes when they are exposed to additional stressors. The similarity of molecular signatures associated with the seemingly disparate traits of aggression and disease suggests that these characteristics may, in fact, be intimately tied.

The order Saprolegniales (Class Oomycota) is a group of fungus-like eukaryotic microorganisms that have been associated with infections in fish and fish eggs. Infections with microorganisms from this order are clearly evident because they have a cotton wool-like appearance. The aim of this study was to characterize and identify an oomycete that was isolated from the eye of an Orange Blotched Peacock Cichlid Aulonacara sp. A sample of cotton wool-like mycelia was isolated and single-spore isolations were conducted. Molecular characterization and phylogenetic analysis of the ITS1-5.8-ITS2 rDNA region for all isolates were used for species identification. Following molecular identification, one isolate was used to culture and characterize the reproductive structures. Physiological characterization entailed incubating the isolate on potato dextrose agar (PDA) at five different temperatures, ranging from 5°C to 25°C, to monitor growth rates. A multiple sequence alignment showed 100% similarity between all of the single-spore isolates and alignment with other Achlya bisexualis strains. Long, coarse hyphae with zoosporangia and gemmae typical of the order Saprolegniales were observed with an optimal growth rate at 25°C. The oomycete that was isolated from an Orange Blotched Peacock Cichlid was identified as A. bisexualis, the first record of this species in South Africa., (© 2019 American Fisheries Society.)

Infectious diseases are the outcome of complex interactions between the host, pathogen, and environment. After exposure to a pathogen, the host immune system uses various mechanisms to remove the pathogen. However, environmental factors and characteristics of pathogens can compromise the host immune responses and subsequently alter the outcome of infection. In this article, genetic and epigenetic factors that shape the individual variation in mounting protective responses are reviewed. Different approaches that have been used by researchers to investigate the genetic regulation of immunity in ruminants and various sources of genetic information are discussed., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The lamprey is a primitive jawless vertebrate that occupies a critical phylogenetic position, and its larval stage represents the major portion of its life cycle [1]. Lamprey larvae have been proven to be an important model organism for studying numerous biological problems, such as the immune system, due to their unique biological features [2]. In addition, early-stage larvae have never been obtained from the wild [3]; therefore, it is necessary to establish artificial breeding of lampreys in the laboratory. However, during early development, the larvae exhibit susceptibility to saprolegniasis, and the immune responses of lamprey larvae to this infection remain poorly understood. Here, we established a model of fungal infection in lamprey larvae and then used RNA sequencing to investigate the transcript profiles of lamprey larvae and their immune responses to Saprolegnia ferax. Among the profiled molecules, genes involved in pathogen recognition, inflammation, phagocytosis, lysosomal degradation, soluble humoral effectors, and lymphocyte development were significantly upregulated. The results were validated by analysis of several genes by quantitative real-time PCR and whole-mount in situ hybridization. Finally, we performed a Western blot for VLRs in infected and uninfected lampreys. This work not only provides an animal model for studying fungal infection but also suggests a molecular basis for developing defensive strategies to manage Saprolegnia ferax infection., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A retrospective study was conducted using 250 clinical records of brown trout (Salmo trutta L.) with saprolegniosis by Saprolegnia parasitica, which had been collected from 8 rivers and 1 fish farm in the province of León (Spain). A geographic information system (GIS) was used to obtain skin lesion distribution patterns in males and females. Lesions in wild brown trout affected 15.31 ± 13.33% of the body surface, with a mean of 12.76 ± 6.56 lesions per fish. In addition, 51.23% of wild trout presented lesions with necrosis of the skin or fins. The pattern obtained when not distinguishing between sexes indicated that saprolegniosis lesions are mainly located above the lateral line and most frequently affect the dorsal cephalic region, the adipose fin, the peduncle and the caudal fin. However, differences were observed between males and females. Farmed trout presented a lower percentage of affected body surface (2.06 ± 4.36) and a lower number of lesions with and without necrosis because they received preventive treatment for saprolegniosis., (© 2019 John Wiley & Sons Ltd.)

Multiple stressors are commonly encountered by wild animals, but their cumulative effects are poorly understood, especially regarding infection development. We conducted a holding study with repeated gill and blood sampling to characterize the effects of cumulative stressors on infection development in adult coho salmon. Treatments included chronic thermal stress (15°C vs. 10°C) and acute gill net entanglement with an air exposure (simulating fisheries bycatch release). The potential loadings of 35 infectious agents and the expression of 17 host immune genes were quantified using high-throughput quantitative polymerase chain reaction, while host physiology was characterized with chemical analysis of blood. Temporal increases in infectious agent richness and loads were concurrent with decreased expression of immune genes in fish sampled in the river. In the laboratory, mortality was minimal in cool water regardless of fishery treatment (<15%). Elevated water temperature under laboratory conditions increased mortality of males and females (8% and 28% mortality, respectively, delayed by >1 wk) and enhanced mortality associated with handling and biopsy (∼40% both sexes). Experimental gillnetting at high temperature further enhanced female mortality (73%). Fish held at high temperature demonstrated heavier infectious agent loads, osmoregulatory impairment, suppressed female maturation, and upregulation of inflammatory and extracellular immune genes. At high temperature, heavy Parvicapsula minibicornis loads were associated with premature mortality. Females exhibited physiological impairment from both stressors after 1 wk, and infection burdens correlated poorly with immune gene regulation compared with males. Cumulative effects of multiple stressors on female mortality are likely a function of physiological impairment and enhanced infections at high temperature.

Thirty-nine equine cheek teeth diagnosed as having anachoretic apical infections and also having occlusal fissure fractures, but without occlusal pulpar exposure, that had been orally extracted without causing occlusal damage and 10 control teeth were used in this study. The teeth were individually imaged by computed tomography, occlusally stained with methylene blue and visually reexamined, then sectioned subocclusally at 5 mm intervals until the fissure fractures could no longer be detected. A limited histological study was then performed on 7 apically infected and 5 control teeth. Standard computed tomography only detected 1 of 39 fissure fractures. Thirteen of the 39 stained teeth had subocclusal fissure fractures visually identified at approximately 6 mm beneath the surface, and in 9 of these 13 teeth the fissure fractures had deeper staining to a level immediately above or into a pulp horn, indicating a potential route for bacterial pulpitis. However, the current study cannot rule out the possibility that the extraction process, long-term formalin storage, or the processing of teeth may have allowed for deeper staining. Additionally, methylene blue may penetrate dental tissue more readily than bacteria can invade. Further studies on the potential role of fissure fractures in the etiopathogenesis of cheek teeth apical infection are warranted.

Livestock are critical component for supporting the sustainable agriculture in the current global scenario. In the era of artificial intelligence and automation in field of livestock, sensors play an important role. Electrochemical sensor is the type of sensor which holds reliability and tremendous promise in raising the animal productivity in developing world. An early and accurate diagnosis of the animal pathogen and metabolic status are the cornerstone for better animal productivity. The available diagnostic techniques require tedious sample preparation, sophisticated instrument, dedicated laboratory, trained personnel and it is time consuming also. The electrochemical biosensor technology might be a smart solution because of its sensitivity, simplicity, low cost, possible miniaturization and potential ability for real-time analysis. In the veterinary disease diagnostics, various biosensors including electrochemical biosensors have been developed recently, based on disease specific biomarkers. The main focus of article is on reviewing the research in detection of animal infectious and metabolic diseases, hormonal analysis and sweat analysis with electrochemical biosensor., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Psittacines (e.g. parrots, macaws and cockatoos) are common companion animals that are also kept in zoos and private breeding collections. Despite this popularity, long-term, comprehensive studies of diagnostic data from captive psittacines are rare. This study was conducted to assess trends in disease prevalence and to describe causes of morbidity and mortality in psittacines submitted for post-mortem examination to the veterinary hospital and diagnostic laboratory at the University of Guelph, Ontario, Canada. Post-mortem reports of 1,850 psittacines from 1998 to 2017 were assessed and included 110 species from 45 genera. Birds were often diagnosed with infectious disease processes (n = 823; 44.5%), including viral (n = 428; 23.1%), bacterial (n = 284; 15.4%) and fungal (n = 161; 8.7%). Non-infectious disease processes (n = 1,076; 58.2%) were most commonly degenerative (n = 465; 25.1%), metabolic (n = 392; 21.2%) or haemodynamic (n = 270; 14.6%). Exploratory statistical analyses, used to guide further research, revealed significant correlations and associations among disease processes and genera, age categories and sex. This 19-year retrospective study is the first to be conducted in Canada for psittacine birds and provides a broad overview of disease prevalence that can be used as a baseline to inform other studies addressing common and uncommon diseases affecting these birds in the future., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.)

Bovine herpesvirus 1 (BHV1) is an important bovine pathogen, responsible for respiratory diseases and reproductive problems. This study investigated the penetration capacity of BHV1 into oocytes after co-incubation for either 1 h or 24 h. Immunofluorescence assays in cumulus-oocyte complexes (COCs) and denuded oocytes (without the presence of cumulus cells) were performed and evaluated using confocal laser scanning microscopy. Blood samples and ovaries from BHV1 seronegative cows were used. The oocytes recovered were divided into two groups. Group I comprised COCs (n = 312) and denuded oocytes (n = 296), which were experimentally infected with BHV1 and incubated for 1 h at 38.5°C and 5% CO2. Group II comprised COCs (n = 425) and denuded oocytes (n = 405), which were co-incubated with BHV1 under the same conditions for 24 h. The negative control of these two groups was respectively subjected to the same protocol, except for exposure to BHV1. To our knowledge, this study provides the first evidence of BHV1 detection within COCs and denuded oocytes exhibiting intact zona pellucida when co-incubated with the virus for 24 h. Immunolocalization also confirmed the presence of BHV1 in the cytoplasm of the cumulus cells of all COCs exposed to the virus after both incubation periods. In conclusion, detection of BHV1 inside oocytes has a great meaning for the field of animal reproduction. The detection of BHV1 in different layers of cumulus cells also demonstrates that these cells are sources of viral infection., Competing Interests: The authors have declared that no competing interests exist.

Saprolegniasis is one of the most economical and ecologically harmful diseases in different species of fish. Low water temperature is one of the most important factors which increases stress and creates favourable conditions for the proliferation of Saprolegniasis. Therefore, the monitoring of water surface temperature (WST) is fundamental for a better understanding of Saprolegniasis. The objective of this study was to develop a predictive algorithm to estimate the probability of fish kills caused by Saprolegniasis in Río Tercero reservoir (Argentina). WST was estimated by Landsat 7 and 8 imagery using the Single-Channel method. Logistic regression was used to relate WST estimated from 2007 to 2017 with different episodes of fish kills by Saprolegniasis registered in the reservoir during this period of time. Results showed that the algorithm created with the first quartile (25th percentile) of the WST values estimated by Landsat sensors was the most suitable model to estimate Saprolegniasis in the studied reservoir., (Copyright © 2019. Published by Elsevier B.V.)