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Peroxisomicine A1 (PA1) is a toxin isolated from the

The addition prebiotics in broiler diets can benefit digestion and nutrient abortion. The objective of the present study was to evaluate the effects of moringa leaf powder and agave inulin on growth performance, intestinal morphology, and slaughter traits of broiler chickens over 40 d of grow-out. A total of 280 broilers (Ross 308) aged 1 d were randomly allocated to 4 treatments, with 7 replicates each and 10 chicks per replicate: T1 = control diet, T2 = control diet with 15 g/kg of moringa leaf powder, T3 = control diet with 15 g/kg of agave inulin, and T4 = control diet with 15 g/kg of moringa leaf powder and 15 g/kg of agave inulin. The results showed that analysis of treatments at time were not different (P > 0.05) for broiler weights, feed and water intake, and weight gain. Treatment was significant (P

Summary Mixed pneumoconiosis is a pulmonary disease associated with several inhaled mineral irritants. Dust was found in the alveolar macrophages, alveolar and bronchial walls and pulmonary interstitial tissue of two female coyotes (Canis latrans). The dust contained large amounts of silica, coal, iron and copper particles, which were associated with severe pulmonary disease. Lung injury in the animals was characterized by pulmonary nodules, severe interstitial fibrosis, alveolar hyperplasia and bone formation within alveolar spaces. Coyotes inhaled mineral dust while roaming a field close to three mineral extraction zones. To our knowledge, this is the first report of the concomitant inhalation of multiple minerals in association with diffuse pulmonary ossification in the pulmonary parenchyma of two wild canine animals.

Background and Objectives: Nutritional deficiencies are one of the main triggers for the development of gastrointestinal diseases, such as ulcerative colitis (UC). Therefore, the objective of the present work consisted of determining the nutrients present in the bone broth (BB) and evaluating their anti-inflammatory properties in a murine model of UC, induced by intrarectal administration of 2, 4, 6-trinitrobenzene sulfonic acid (TNBS), and acetic acid (AcOH). The BB was prepared from the femur of bovine cattle and cooked in distilled water for 8 h at 100 ± 2 °C. Materials and Methods: The BB was administered ad libitum to BALB/c mice for 10 days before the induction of UC. Colon samples were collected for histological analysis and determination of cytokine expression levels by qPCR. Results: It was found that amino acids (AA) are the main nutritional contribution of BB, 54.56% of these correspond to essential AA. The prophylactic administration of BB in the murine model of UC reduced histological damage, decreased the expression of IL-1β (61.12%), IL-6 (94.70%), and TNF-α (68.88%), and increased the expression of INF-γ (177.06%), IL-4 (541.36%), and IL-10 (531.97%). Conclusions: This study shows that BB has anti-inflammatory properties, and its consumption can decrease the symptoms of UC.

Encephalitozoon cuniculi is an important microsporidian pathogen that is considered an emergent, zoonotic, and opportunistic. It infects both domestic and laboratory rabbits, generating severe chronic interstitial and granulomatous nephritis with fibrosis and granulomatous encephalitis. Encephalitozoonosis is diagnosed in paraffin-embedded sections by examining the spores in the host tissues. The spores are difficult to observe when the samples are stained with hematoxylin and eosin (H&E), particularly when there is an inflammatory reaction and tissue damage. The spores are easily mistaken for other microorganisms, such as fungi (yeasts), protozoa, and bacteria. In our study, we used kidney samples from E. cuniculi–positive rabbits and employed 14 recommended histologic stains for detecting microsporidia spores: alcian blue, calcofluor white, Giemsa, Gram, Grocott, H&E, Luna, Luxol fast blue, Masson trichrome, modified trichrome stain (MTS), periodic acid–Schiff reaction (PAS), Van Gieson, Warthin–Starry (WS), and Ziehl–Neelsen (ZN).We concluded that MTS and Gram stain, detected by light microscopy, and calcofluor white stain, detected by ultraviolet light microscopy, are the best stains for detecting spores of E. cuniculi in paraffin-embedded tissues from infected rabbits. These stains were superior to WS, ZN, Giemsa, and PAS for identifying spores without background “noise” or monochromatic interference. Also, they allow individual spores to be discerned in paraffin-embedded tissues. MTS allows observation of the polar tube, polaroplast, and posterior vacuole, the most distinctive parts of the spore.

Encephalitozoon cuniculi is a fungi-related, obligate, zoonotic, spore-forming intracellular eukaryotic microorganism. This emerging pathogen causes granulomas to form in the brain and kidneys of infected individuals. The objective of the current study was to detect the distribution of TNF-α- and IL-4-positive cells using immunohistochemistry within these granulomas in both infected immunocompetent (group A) and immunosuppressed (group B) New Zealand white rabbits. In the brain, labeled TNF-α immune cells were mainly located in the granuloma peripheries in group B. Granulomas examined in the kidneys of groups A and B were TNF-α positive, but were significantly different (p 0.001) when compared with the brain. IL-4-producing immune cells in the brain and kidneys were disseminated within granulomas in groups A and B; however, no significant difference (p 0.05), was observed. IL-4 positive cells were more numerous in brain sections of group B and differed significantly (p 0.05) when compared with kidneys. Granulomas were not observed in control animals (groups C and D). In conclusion, we identified TNF-α positive cells in both the brain and kidneys of immunocompetent and immunosuppressed animals; IL-4 positive cells were numerous in the brains of immunosuppressed rabbits; however, in terms of percentage were numerous in the brains of immunocompetent rabbits. Immunosuppression appeared to stimulate a change in the cellular phenotype of Th1- to Th2-like granulomas in the brain and kidneys via an unknown mechanism. Expression of pro- and pre-inflammatory cytokines in microsporidian granulomas suggests a mechanism by which E. cuniculi evades the immune response, causing more severe disease. These results increase our understanding of TNF-α and IL-4-positive cells within the E. cuniculi granuloma microenvironment.

Encephalitozoon cuniculi (E. cuniculi) is a fungi-related, obligate, zoonotic, spore-forming intracellular eukaryotic microorganism. This emerging pathogen causes granulomas in brain and kidneys of infected individuals. The objective of this study was to detect the distribution of CD4, CD8 and MHCII-positive cells within granulomas in these organs in infected immunocompetent (group A) and infected immunosuppressed (group B) New Zealand white rabbits using immunohistochemistry. In brain, labeled CD4 immune cells were mainly located in the periphery of granulomas in group B. Kidneys of groups A and B, displayed CD4-positive in granulomas and were significant different when compared to brain. CD8 immune cells in brain and kidneys were disseminated in the granulomas in groups A and B; however, no significant difference was observed. MHCII-positive cells were more numerous in brain sections of group B and were significantly different when compared to kidney sections. Granulomas were not observed in control animals of group C and D. In conclusion, we identified CD4-positive cells in both the brain and kidneys of immunocompetent and immunosuppressed animals; CD8-positive cells were more numerous in brain of immunosuppressed rabbits and MHCII cells were more predominant in brain of immunocompetent rabbits. Apparently, the immunosuppression stimulated a change in the cellular phenotype of Th1- to Th2-like granulomas in brain and kidneys by an unknown mechanism. These results increase our understanding of CD4, CD8 and MHCII positive cells within the E. cuniculi granuloma microenvironment and will help in future microsporidian granulomas studies of both immunocompetent and immunosuppressed individuals.

The biological behavior of teratomas depends on several interdependent clinical and epidemiological variables such as age at diagnosis, sex, tumor microenvironment, and tumor morphology, among others. All these variables are correlated to different cytogenetic and molecular aberrations (Harms et al., 2006). There are null reports of teratomas in pigs. The aim of this study was to characterize the tissues present in a mature congenital intraneural teratoma in the cerebellum area of a Landrace female pig of 6-7 weeks old. In this study, tissue control samples were used to validate each staining method. Sections from the teratoma showed normal histology of the cerebellum, including rounded Purkinje neurons with abundant cytoplasm, euchromatic nuclei, and prominent nucleoli; glial cells with a scarce amount of cytoplasm and small and highly basophile-nuclei (compact chromatin) and axonal tracts (white matter). Interestingly, we also observed areas with tissues different from the nervous tissue, including bundles of well-defined skeletal muscle fibers with a striated pattern and peripheral nuclei; hyaline cartilage plaques, with prominent presence of chondrocytes in their lagoons forming isogenous groups surrounded by a territorial and interterritorial matrix; trabeculated bone tissue; and adipocytes, which are ring-shaped cells with peripheral flattened nuclei, as a result of the presence of a central large lipid droplet. To our knowledge, this study is the first to describe a congenital intraneural mature teratoma in the cerebellum of a pig.

We provide the first report of Acanthocephala (Prosthenorchis elegans) in Mexican non-human primates. There has been no known treatment against this parasite except for surgical removal, and this has been relatively ineffective because of the small juveniles. We report the presence of P. elegans in a captive breeding colony of squirrel monkeys (Saimiri sciureus) in Mexico, and we describe a successful treatment protocol. Treatment involved 2 steps: oral administration of the drugs loperamide chlorhydrate (0.5 mg/0.9 kg/3 days) and niclosamide (0.2 mg/0.9 kg/3 days) followed by surgical removal of adult worms from the intestine. Fecal examination during treatment revealed live adults but no living juveniles and no eggs. Surgery after 1 wk of treatment revealed the presence of adults and an absence of juvenile parasites. All adults were physically extracted during the surgery. All subjects recovered from surgery within 1 wk.

Encephalitozoon cuniculi is an obligate macrophage parasite of vertebrates that commonly infects rodents, monkeys, dogs, birds, and humans. In the present study, we aimed to assess the phagocytosis and intracellular survival of E. cuniculi spores using untreated and lipopolysaccharide (LPS)-activated J774A.1 murine macrophages and assess the macrophage viability. The experimental groups comprised untreated spores, spores killed by heat treatment at 90 °C, and spores killed by treatment with 10% formalin. LPS-activated macrophages significantly increased the phagocytosis of spores and reduced their intracellular growth after 24 and 48 h (P

The expression of tumor necrosis factor (TNF) -α, interleukin (IL) -4 and IL-10, as well as apoptosis and nitric oxide (NO) levels were measured in the brain and kidneys of immunocompetent and immunosuppressed New Zealand White rabbits infected with Encephalitozoon cuniculi. All of the animals had clinical signs histopathological lesions compatible with encephalitozoonosis and were E. cuniculi-positive by using a carbon immunoassay test. Encephalitozoon cuniculi infection promoted the expression of TNF-α and NO production in the kidneys of infected rabbits, and a synergic effect was observed in animal treated with dexamethasone. The IL-4 expression was similar in the brain and kidneys of infected rabbits, regardless of their immunologic status. The IL-10 mRNA expression in the brain of infected immunosuppressed rabbits was elevated when compared with positive controls. Apoptosis of granuloma mononuclear-like cells was detected in immunocompetent E. cuniculi-infected rabbits, but it was more evident in infected-immunosuppressed animals. Nitric oxide levels were elevated both in immunocompetent and immunosuppressed infected animals, but it was more apparent in the kidneys. These data suggest that modulation of the immune response by E. cuniculi could contribute to the survival of the parasite within phagocytic cells in granulomas via an as yet undetermined mechanism.

Tracheal leiomyoma is a rare neoplasm of the respiratory tract in animals. This primary benign tumor arises from smooth muscle cells of the trachea. We report a 13-year-old female horse with clinical signs of severe airways obstruction. It had dyspnea, exercise intolerance, chronic progressive respiratory noises, and cyanosis in mucosa membranes. Radiography revealed a foreign body obliterating the luminal trachea. Endoscopic biopsy showed a 3 × 3-cm ovoid mass attached to the dorsal aspect of the trachea. Hematoxylin and eosin and Masson's trichrome stains showed dense spindle cells forming irregular bundles disposed in short interlacing fascicles. Nuclei were elongated with blunt ends, eosinophilic cytoplasm with indistinguishable cell borders, and low mitotic activity. This study is considered the first reported case of an obstructive intratracheal leiomyoma in the horse.

A female coyote (Canis latrans) was fatally injured by a vehicle on a road in San Luis Potosi, Mexico. Because of deteriorating clinical signs, the animal was euthanized. Postmortem examination of the lungs showed numerous small multifocal white nodules (0.5–1 cm diameter) disseminated throughout. Histopathologic examination revealed multifocal coalescing granulomas with abundant macrophages, numerous neutrophils, fibroblasts, plasma cells, and lymphocytes. Abundant intracellular and extracellular thick-walled, refractile, spherical yeasts (10–15 μm) were observed within the granulomas. The yeasts were intensely PAS-positive, with granular protoplasm. Broad-based single budding yeasts were occasionally present. Based on the microscopic findings of the pulmonary lesions and the morphological features of the organism, a diagnosis of chronic pyogranulomatous pneumonia caused byBlastomyces dermatitidiswas made. To our knowledge, the case described herein is the first report of pulmonary blastomycosis in a wild coyote.

Levels of interferon (IFN)-γ and interleukin (IL)-10 were measured in the serum of immunocompetent and immunosuppressed New Zealand White rabbits naturally infected with Encephalitozoon cuniculi. IFN-γ levels were elevated in infected rabbits, and a synergic effect was observed in animals treated with the immunosuppressive agent dexamethasone (Dex). The role of IL-10 in infected rabbits remains unclear, as IL-10 levels were similar to those of negative controls. Dex appeared to exhibit a proinflammatory effect, as IFN-γ levels were elevated in infected immunosuppressed rabbits. Similarly, Dex exhibited a synergic effect in infected immunosuppressed rabbits, as evidenced by the elevation in IFN-γ production. These data indicate that the immune response to this glucocorticoid should be considered in the design of future animal model studies of immunosuppression.

This is the first confirmed report ofEncephalitozoon cuniculi(E. cuniculi) in farm meat rabbits located in Northern Mexico. Eighty young rabbits exhibited clinical signs of this zoonotic emerging disease, like torticollis, ataxia, paresis, circling, and rolling. Samples of brain, kidney, and liver were examined for histology lesions. For the first time the lesions caused byE. cuniculiwere graded according to their severity (I, II, and III) and the size of the granulomas (Types A, B, and C). The main cerebral injuries were Grade III, coinciding with the presence of Type C granulomas. The cerebral lesions were located in the cortex, brain stem, and medulla. The renal lesions were also Grade III distributed throughout cortex and renal medulla, with no granuloma formation. The involvement of hypersensitivity Types III and IV is suggested. All of the rabbits were seropositive toE. cuniculiby CIA testing, suggesting that this zoonotic and emerging pathogen is widely distributed among animals intended for human consumption. We believe this work could be used as a guide when examiningE. cuniculiand will provide direction to confirm the diagnosis of this pathogen.

Most of the natural cases of pneumonia in feedlot cattle are characterized by a longer clinical course due to chronic lung lesions. Microscopically, these lesions include interstitial fibroplasia, bronchitis, bronchiectasis, bronchiolitis obliterans, and epithelial metaplasia of the airways. Herein, the aim was to review, under a medical perspective, the pathologic mechanisms operating in these chronic pneumonic lesions in calves. Based on the similarities of these changes to those reported in bronchiolitis obliterans/organising pneumonia (BO/OP) and chronic obstructive pulmonary disease (COPD) in human beings, calves are proposed as an alternative animal model.

Summary A Southern two-toed sloth (Choloepus didactylus), originally acquired from French Guiana, died while maintained in quarantine in a pet store in Monterrey, Mexico. Large yeast cells with multiple buds compatible with Paracoccidioides brasiliensis were observed in disseminated granulomatous lesions in the lungs, liver, spleen and kidney. Transmission electron microscopical examination supported the diagnosis. This is the first report of paracoccidioidomycosis in a two-toed sloth.

Algal infections are rare in humans and domestic animals. Prototheca spp. and Chlorella spp. are among the most commonly reported. Herein, we present a brief review on Chlorella spp. infections and related pathologies and discuss this information including a natural case in a sheep in Mexico with a disseminated form of the disease.

Summary Loma salmonae, an obligate intracellular microsporidian parasite, is the causal agent of microsporidial gill disease of salmon (MGDS), characterized by the production, growth and eventual rupture of spore-filled xenomas. MGDS in farmed chinook salmon remains occult until xenoma rupture, at which time the infected fish respond with intense branchitis and high rates of mortality. The present study showed that in experimentally infected fish the rate of change of xenoma diameter could be modelled through regression analysis, particularly through the period of 4‐9 weeks post-infection, yielding the predictive equation: xenoma diameter ¼ 242.9 microns þ15.3 microns x (number of weeks post-infection). This provides a tool for diagnosticians to predict the time to xenoma rupture and hence to the initiation of the clinical phase of MGDS. q 2004 Elsevier Ltd. All rights reserved.

Infection by a microsporidian of the genus Loma was found in gills of cod Gadus morhua. Xenomas contained parasites in multiple stages of development. Some spores looked empty and had everted polar tubes, which were either straight or coiled. These polar tubes were scattered throughout the xenoma cytoplasm, and some of them pierced the plasma membrane. Those outside of the xenoma penetrated neighboring cells, including blood cells. These observations suggest that a mechanism of autoinfection could occur in blood cells and gill tissue, perpetuating the disease in the host.

The early ultrastructural stages of Loma salmonae were studied in the gills of experimentally infected rainbow trout. No parasitic stages were identified during the first 2 wk of the infection. By week 3 postexposure (PE), uninucleate and binucleate meronts were recognized within host cells (no xenomas) associated with the capillary channels of secondary lamellae and lamellar arteries. An inflammatory reaction was absent. In secondary lamellae, infected cells were isolated from the capillary lumen, and some were recognized as pillar cells. In lamellar arteries, infected cells were localized beneath the endothelium and not in the lumen. Inflammatory reaction and destruction of parasites inside blood cells in the lumen of secondary lamellae were observed by week 4 PE. Three hypotheses, i.e., isolation, internalization, and evasion, are proposed to explain the localization of the infected cells in the gills. It is concluded that meronts are the earliest parasitic stage observed by week 3 PE, pillar cells are secondarily infected by phagocytosis of infected cells in the blood, endothelial cells of gills are not infected, and inflammatory response to the parasite starts by week 4 PE.

Immune response to fish microsporidia is still unknown and there are current research trying to elucidate the events involved in the immune response to this parasite. There is evidence suggesting the role of innate immune response and it is clear that adaptive immunity plays an essential part for eliminating and then mounting a solid resistance against subsequent microsporidian infections. This review article discusses the main mechanisms of resistance to fish microsporidia, which are considered under four main headings. 1) Innate immunity: the inflammatory tissue reaction associated with fish microsporidiosis has been studied at the ultrastructural level, providing identification of many of the inflammatory cells and molecules that are actively participating in the spore elimination, such as macrophages, neutrophils, eosinophilic granular cells, soluble factors and MHC molecules. 2) Adaptive immunity: the study of the humoral response is relatively new and controversial. In some cases, the antibody response is well established and it has a protective role, while in other situations, the immune response is not protective or it is depressed. Study of the cellular response against fish microsporidia is still in its infancy. Although the nature of the microsporidian infection suggests participation of cellular mechanisms, few studies have focused on the cellular immune response of infected fish. 3) Immunomodulation: glucans are compounds that can modulate the immune system and potentiate resistance to microorganisms. These compounds have been proposed that can interact with receptors on the surface of leukocytes that result in the stimulation on non-specific immune responses. 4) Vaccination: little is known about a biological product that could be used as a vaccine for preventing this infection in fish. In the Loma salmonae experience, one of the arguments that favor the production of a vaccine is the development in fish of resistance, associated to a cellular immune response. A recently proved spore-based vaccine to prevent microsporidial gill disease in salmon has recently shown its efficacy by considerably reducing the incidence of infection. This recent discovery would be first anti-microsporidian vaccine that is effective against this elusive parasite.

Resistance to re-infection of rainbow trout to Loma salmonae, a microsporidian gill parasite has been previously documented and this study examined how rapidly this resistance develops. Naive rainbow trout were inoculated intraperitoneally (IP) with an inactivated spore-based vaccine and were then given an oral challenge with a high dose of L. salmonae spores at various weeks after being vaccinated. Non-vaccinated naive fish (exposed group) were challenged alongside of each group of vaccinated fish to ensure that the challenges were relatively standardised. In each group of fish, four weeks after the challenge, numbers of xenomas were counted on a gill arch for all fish. Vaccinated trout were completely resistant to a L. salmonae challenge six weeks after vaccination, although the onset of resistance began at approximately week 3, as observed with a reduction in the percent infected and xenoma intensity. The maximum percent infected for the vaccinated fish was 83% following a challenge two weeks following vaccination, whereas for the exposed group the maximum prevalence of 100% was reached several times. With continued research, a spore-based vaccine for L. salmonae has the potential to become the first commercially available parasite vaccine for fish.

The main objective of this investigation was to examine the ultrastructural features of gills from rainbow trout experimentally infected with Loma salmonae to determine the morphological events that occur during the late stages of development of this parasite. Peripheral distribution of the mature parasites inside round xenomas was observed at weeks 5 and 6 postexposure (PE), but eventually the parasite occupied the entire xenoma. Degenerative changes were observed only in immature parasites at week 7 PE, and eventually an inflammatory reaction with a cellular infiltration was directed against mature spores. Round, flattened, and irregular shaped xenomas were observed at week 8 PE. The round xenomas showed a severe inflammatory response with disintegration of the xenoma membrane. This event was accompanied by eversion of polar tubes within the attacked xenoma and by the simultaneous presence of 2 tubular appendages, the type I and II tubules. Flattened xenomas were observed below the endothelium of gill lamella arteries. The irregular xenomas were located in the connective tissue of the gill filament and showed multiple projections occupied by spores. Both flattened and irregular xenomas showed no evidence of inflammatory reaction. An earlier proposed hypothesis is expanded to explain how L. salmonae is implanted beneath lamellar endothelium and within filament connective tissue.

Nematodes similar to Oxyspirura sp. were recovered from the cornea and nictitating membrane of a fulvous owl (Strix fulvescens). The bird had been captive for several months, but died suddenly. It had no clinical history of prior diseases, including ocular lesions.