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A 13-year-old female Persian cat died suddenly after severe respiratory distress. At necropsy, the changes were compatible with congestive heart failure. The heart was enlarged with a flabby and puckered sac-like aneurysm at the apex of the left ventricle. The apical zone showed a thin muscular wall arising from the free wall of the left ventricle connected to a bulged saccular area through a wide communication. Microscopically, the wall of the aneurysm was composed of fibrous connective tissue with neovascularization and sparse atrophied myocardial cells at the margins. A few isolated cardiomyocytes in the lesion stained positively for desmin, and the inner lining of the aneurysm had immunoreactivity to von Willebrand factor and CD31. Mature fibrous connective tissue was interspersed with degenerated and disorganized cardiomyocytes elsewhere in the myocardium, and many small myocardial arteries were tortuous and thickened. In this case of sudden death, the diagnosis was primary cardiomyopathy, with formation of a left ventricular apical aneurysm within an area of marked myocardial fibrosis and cardiomyocyte atrophy. [ABSTRACT FROM AUTHOR]

In biological control, joint releases of predators and parasitoids are standard. However, intraguild predation (IGP) can occur when a predator attacks a parasitoid, potentially affecting pest control dynamics. In addition to the focal prey (FP), Trialeurodes vaporariorum , the intraguild predator (IG-predator) Geocoris punctipes can consume the parasitoid Eretmocerus eremicus (IG-prey). In this IGP context with multiple prey, an alternative prey (AP), like the aphid Myzus persicae , may influence interactions. Theory predicts that, in simple interactions, a predator's functional response (FR) to the FP changes with the presence of an AP. However, whether this holds in an IGP context is unknown. In this study, we empirically tested that prediction. Our results show that without IGP, G. punctipes exhibits a generalized FR with and without AP. Nevertheless, with IGP, the predator exhibited a Type II FR at low and high AP densities, increasing pressure on the FP and potentially favoring short-term biological control strategies. However, when 25 AP were offered, the predator's response shifted, underscoring the importance of monitoring AP densities to prevent potential disruptions in FP control. In both contexts, the increase in AP produced a handling time increase and a decrease in consumption rate. These results indicate that the theoretical prediction of the effect of AP on the FR is met only under specific conditions, and the complexity of multitrophic interactions must be considered.

Background: Metabolic reconfiguration in plants is a hallmark response to insect herbivory that occurs in the attack site and systemically in undamaged tissues. Metabolomic systemic responses can occur rapidly while the herbivore is still present and may persist in newly developed tissue to counterattack future herbivore attacks. This study analyzed the metabolic profile of local and newly developed distal (systemic) leaves of husk tomato (Physalis philadelphica) plants after whitefly Trialeurodes vaporariorum infestation. In addition, the effect of these metabolomic adjustments on whitefly oviposition and development was evaluated., Results: Our results indicate that T. vaporariorum infestation induced significant changes in husk tomato metabolic profiles, not only locally in infested leaves, but also systemically in distal leaves that developed after infestation. The distinctive metabolic profile produced in newly developed leaves affected whitefly nymphal development but did not affect female oviposition, suggesting that changes driven by whitefly herbivory persist in the young leaves that developed after the infestation event to avoid future herbivore attacks., Conclusions: This report contributes to further understanding the plant responses to sucking insects by describing the metabolic reconfiguration in newly developed, undamaged systemic leaf tissues of husk tomato plants after whitefly infestation. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)

Melanocyte-derived tumours are common in humans and animals and their spontaneous occurrence in dogs and the clinicopathological progression in malignant presentations is comparable with humans. Melanomas are a heterogeneous group of malignant neoplasms and several subtypes have been classified, including angiomatoid melanoma, of which only five cases have been reported in humans but none in animals. We now document cases of primary angiomatoid melanoma in the skin and oral cavity of two dogs. Neoplastic cells resembling endothelial cells that lined large blood vessels in the tumours were immunonegative for CD34 but intensely positive for SOX10., Competing Interests: Conflicts of Interest Statement The authors declared no potential conflicts of interest in relation to the research, authorship or publication of this article., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The changes associated with condemned lungs in cattle with chronic pleural lesions of the caudal lobes were characterized by histology and immunohistochemistry (IHC). Fibroproliferative pleural lesions were microscopically confirmed. Occasionally, the pleural lesions also included adipose, chondroid, and osseous metaplasia that were covered by mesothelial cells, mostly in the absence of inflammation. Other lungs also showed fibrosis in the subpleural interstitium and interlobular septa. In both condemned and noncondemned lungs, immunoreactivity to Wilms tumor 1 (WT1) was normally observed on surface mesothelial cells but not on the submesothelial fibroblasts and myofibroblasts. Conversely, the myofibroblasts beneath the pleura, but not the mesothelial cells, showed immunoreactivity to alpha smooth muscle actin and calponin. However, in the lungs with myofibroblastic foci in the pleura, the proliferated cells maintained WT1 immunoreactivity similar to those of some metaplastic cells. These findings may reflect the plasticity of mesothelial cells in vivo.

Context: Exosomes secreted by tumor cells are a good source of cellular components that stimulate the immune response, such as alarmins (mRNA, tetraspanins (CD9, CD63, CD81), heat-shock proteins, major histocompatibility complex class I molecules) and tumor-associated antigens. These properties permit to pulsed dendritic cells in the immunotherapy for many cancers types. The aim of this study was to demonstrate the use of exosomes derived from canine transmissible venereal tumor (CTVT) as an antigen to pulsed dendritic cells and its administration in dogs with CTVT as treatment against this disease. Material and methods: From primary culture of CTVT cells the exosomes were isolated and characterized by scanning electron microscopy assay, dot blot and protein quantification. The monocytes of each patient were differentiated to dendritic cells (DC) and pulsed with CTVT exosomes (CTVTE). Phagocytosis, tumor size, populations of lymphocytes and IFN-c levels were evaluated. Results: The CTVTE showed a size around 90 nm. CD81, CD63, CD9 and Hsp70 were expressed. Monocytes showed an expression of 85.71% for CD14 + , 12.3% for CD80 + , 0.1% for CD83 + and 0.8% for DLA-II. In DC 5.1% for CD14 + , 86.7% for CD80 + , 90.1% for CD83 + and 92.6% for DLA-II and a phagocytosis of 63% was obtained by FITC Dextran test. No side effects were observed in the experimental groups with our therapy. Tumor regression was of 100% at the seventh week, as well as an increase in the level of IFN- γ (142 pg/ml), and CD4 + (28%) and CD8 + (34%) cell percentage. Discusion and conclusion: These results have shown that DC pulsed with tumor exosomes induce regression of the TVT in dogs.

Didelphostrongylus hayesi is an important and prevalent pulmonary nematode in the opossum ( Didelphis virginiana ). An in-depth description of the pulmonary lesions caused by this nematode is lacking. The objective of this investigation was to make a detailed account of the gross, subgross, and microscopic changes that occur in the lungs of opossums naturally infected with D. hayesi. Forty-four opossums trapped in the state of Colima, Mexico, were euthanized by an overdose of barbiturates. Following a postmortem examination, the right lung was cut from the main bronchi and placed in a Petri dish containing a saline solution for the detection and identification of live parasites. The left lung was fixed and cut serially for subgross microscopic examination and sections of lung were cut and stained for histopathologic examination. The most remarkable gross change in parasitized lungs was a poorly collapsible pulmonary parenchyma and mild emphysema. The right lung tested positive for lungworms on gross examination in 20/44, and 11/44 (25%) of the left lungs showed tan nodules on the pleural surface. Microscopically, the bronchi of 20/44 animals harbored adult and larval stages of D. hayesi (left lung), the same 20 opossums from which nematodes were grossly evident at necropsy (right lung). Adults and larvae were present in bronchi, bronchioles, and alveoli mixed with desquamated cells and many eosinophils, and to a lesser extent neutrophils, alveolar macrophages, and giant cells. Bronchi and bronchioles exhibited goblet cell hyperplasia and metaplasia respectively, and infiltration of lymphoplasmacytic cells in the interstitium and lamina propria. The tan nodules consisted of focal alveolar endogenous lipidosis, which likely resulted from parasitic airway obstruction. The lungs of 3/20 parasitized opossums also showed alveolar bronchiolization (Lambertosis). The absence of Eucoleus aerophilus or bacterial pneumonia incriminates D. hayesi as the putative cause of pulmonary lesions in these opossums.

Coccidioidomycosis is a respiratory fungal infection with occasional systemic dissemination. The disseminated coccidioidomycosis is considered a multifaceted disease. In medicine, disseminated coccidioidomycosis is included within a group of infectious diseases that have been referred as the great imitators. In many cases, malignancies are included in the presumptive diagnosis. In veterinary medicine, disseminated coccidioidomycosis is common in dogs. Nonetheless, despite of being a diagnostic dilemma, disseminated coccidioidomycosis is underestimated and frequently not included into differentials, even in endemic zones. Herein, we describe three cases of granulomatous inflammation caused by Coccidioides spp. which were masquerading malignancies in dogs (0.39 %). The presumptive diagnoses in these cases were osteosarcoma, lymphoma and neurofibroma, respectively. A PCR assay employing tissues in paraffin blocks resulted positive for C. posadasii in one of these cases. A comparative discussion on the ambiguous clinic-pathological presentation of disseminated coccidioidomycosis in dogs and humans is included.

Imidacloprid, one of the most commonly used insecticides, is highly toxic to bees and other beneficial insects. The regulatory challenge to determine safe levels of residual pesticides can benefit from information about the time-dependent toxicity of this chemical. Using published toxicity data for imidacloprid for several insect species, we construct time-to-lethal-effect toxicity plots and fit temporal power-law scaling curves to the data. The level of toxic exposure that results in 50% mortality after time t is found to scale as t(1.7) for ants, from t(1.6) to t(5) for honeybees, and from t(1.46) to t(2.9) for termites. We present a simple toxicological model that can explain t(2) scaling. Extrapolating the toxicity scaling for honeybees to the lifespan of winter bees suggests that imidacloprid in honey at 0.25 μg/kg would be lethal to a large proportion of bees nearing the end of their life.

The number of large feedlot operations, similar to that of USA and Canada, has notably increased in Mexico in the last three decades. Clinical and laboratory diagnoses of neurological diseases in feedlot cattle are crucial in Mexico and Central America because of the high incidence of bovine paralytic rabies (BPR). Because of its zoonotic potential, BPR must be promptly diagnosed and differentiated from other bovine neurological diseases such as thrombotic meningoencephalitis (TME), polioencephalomalacia (PEM) and botulism. More recently, BPR and botulism have been diagnosed with increasing frequency in Mexican feedlots. Neither BPR nor botulism has relevant gross lesions, thus post-mortem diagnosis without laboratory support is impossible. Herein, we describe five outbreaks of neurological diseases in Mexican feedlots in which BPR, botulism and PEM were diagnosed either independently or in combination. A diagram illustrating the most conspicuous pathologic findings and ancillary laboratory test required to confirm the diagnoses of these neurological diseases in feedlot cattle is proposed.

Volatile organic compounds (VOCs) emitted from plants in response to insect infestation can function as signals for the attraction of predatory/parasitic insects and/or repulsion of herbivores. VOCs also may play a role in intra- and inter-plant communication. In this work, the kinetics and composition of VOC emissions produced by tomato (Solanum lycopersicum) plants infested with the greenhouse whitefly Trialeurodes vaporariorum was determined within a 14 days period. The VOC emission profiles varied concomitantly with the duration of whitefly infestation. A total of 36 different VOCs were detected during the experiment, 26 of which could be identified: 23 terpenoids, plus decanal, decane, and methyl salicylate (MeSA). Many VOCs were emitted exclusively by infested plants, including MeSA and 10 terpenoids. In general, individual VOC emissions increased as the infestation progressed, particularly at 7 days post-infestation (dpi). Additional tunnel experiments showed that a 3 days exposure to VOC emissions from whitefly-infested plants significantly reduced infection by a biotrophic bacterial pathogen. Infection of VOC-exposed plants induced the expression of a likely tomato homolog of a methyl salicylate esterase gene, which preceded the expression of pathogenesis-related protein genes. This expression pattern correlated with reduced susceptibility in VOC-exposed plants. The observed cross-kingdom effect of plant-plant signaling via VOCs probably represents a generalized defensive response that contributes to increased plant fitness, considering that resistance responses to whiteflies and biotrophic bacterial pathogens in tomato share many common elements.

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.

We assessed in the laboratory the attraction of the parasitoid Cotesia marginiventris (Cresson) toward odors emitted by conventional maize (Zea mays L. ssp. mays) and Bt (Bacillus thuringiensis) maize seedlings following actual or simulated injury by Spodoptera frugiperda (Smith), the parasitoid's host, and emitted by the host's frass, produced following consumption of conventional or Bt maize seedlings. Females of C. marginiventris exhibited similarly strong responses to conventional and Bt maize seedlings injured by the host or with simulated injury, and these were stronger than responses to clean air. In contrast, the responses of C. marginiventris females were consistently weaker toward host frass derived from Bt maize tissue compared to frass derived from conventional maize tissue. We hypothesized that the weakened response was due to a detrimental effect of Bt endotoxins, present in the Bt maize tissue, on the bacterial community present in the host's gut and frass, including bacteria that produce odors attractive to C. marginiventris. As an initial test of our hypothesis, we compared between the responses of C. marginiventris females to host frass produced following consumption of Bt maize and frass produced from conventional maize which had been treated with an antibiotic (tetracycline) to eliminate host gut bacteria. Our results showed that C. marginiventris females responded similarly weakly to host frass derived from conventional maize tissue treated with antibiotic and to frass derived from Bt maize tissue, treated or untreated with antibiotic, while they responded strongly to frass derived from conventional maize untreated with antibiotic, so provided initial, partial support for our hypothesis. We discussed the weakened response of C. marginiventris females to host frass derived from Bt maize in the context of plausible impacts of transgenic crop cultivars on parasitoid foraging and populations, and the implications for biological control of non-target, polyphagous pests, such as S. frugiperda.

A 3 1/2-month-old pug with oculonasal discharge and seizures was submitted for postmortem examination. Grossly, the lungs had cranioventral consolidation, and microscopically, 2 distinct types of inclusion bodies compatible with Canine distemper virus and Canine adenovirus type 2. Presence of both viruses was confirmed via immunohistochemical staining.

Surfactant protein D (SP-D) is a collagenous calcium-dependent lectin constitutively expressed by alveolar type II pneumocytes and non-ciliated bronchiolar epithelial (Clara) cells. It binds to surface glycoconjugates expressed by a wide variety of microorganisms such as Gram-negative bacteria, influenza A virus, and various fungi, leading to pathogen inactivation or enhanced neutrophil and macrophage activity. Since a hallmark of bronchopneumonia is the initiation of inflammation in the bronchi and bronchoalveolar junction, we chose a classic ruminant model of bronchopneumonia caused by Mannheimia haemolytica to study the expression of SP-D within the bronchioles of infected lambs. Healthy weaned lambs were inoculated with either pyrogen-free saline (controls) or M. haemolytica intrabronchially using a fiber-optic bronchoscope. SP-D protein and mRNA expression in lung was detected by immunohistochemistry (IHC) and fluorogenic real-time relative quantitative reverse transcriptase polymerase chain reaction (real-time RT-PCR), respectively, during acute (1 day), subacute (15 days), and chronic (45 days) bronchopneumonia. At 15 and 45 days post-inoculation, areas of lung had peribronchiolar inflammatory cell infiltrate, epithelial cell hyperplasia, tortuosity of the airway lumens, and decreased intensity of SP-D protein staining and number of positive cells. The levels of SP-D mRNA were not increased or significantly altered by M. haemolytica infection when compared to control animals. In conclusion, cell-associated SP-D protein expression significantly decreases within hyperplastic epithelium of lungs from infected animals during chronic bronchopneumonia. Exhaustion of SP-D protein reserves and absence of SP-D gene upregulation during the progression of bacterial pneumonia into chronicity may result in failure to clear the pathogen from the lung and/or cause animals to be more susceptible to re-infection.

Anionic peptides (APs) are small anionic antimicrobial peptides composed of 7 aspartic acid residues and are produced in the lungs of humans, sheep, and cattle. Although expression by epithelial cells of some antimicrobial peptides (e.g., beta-defensins) of humans and ruminants is increased in response to acute infection, AP expression is not increased during acute infection, which suggests that the expression of the latter peptide is constitutive. In this study, the degree of AP expression during the progression (acute, subacute, and chronic) of bronchopneumonia was determined. Mannheimia (Pasteurella) haemolytica, a known inducer of bovinebeta-defensins, was inoculated intrabronchially with a fiber-optic bronchoscope in nine 3-month-old sheep, and tissues were collected at 1, 15, and 45 days postinoculation (p.i.); nine control animals received pyrogen-free saline by the same procedure and were killed at the same time points. In the acute group (1 day p.i.), the lungs had lesions typical of bronchopneumonia and the distribution and intensity of AP immunoreactivity (AP-IR) were similar to those of previous studies (minimal intensity and distribution of AP-IR in bronchiolar epithelial cells). In the subacute group (15 days p.i.), there was prominent hyperplasia of bronchiolar and alveolar epithelial cells, and the chronic group (45 days p.i.) had yet more pronounced hyperplasia. In the subacute and chronic groups, the intensity and distribution of AP-IR in the cytoplasm of hyperplastic bronchiolar and type II alveolar cells were significantly increased compared to those of saline-inoculated and contralateral (noninoculated) lung lobes. Although AP expression appears constitutive, the constitutive production of AP is higher in hyperplastic, less differentiated cells than in fully differentiated, mature cells of the respiratory airways. The increased intensity and distribution of AP-IR in immature (hyperplastic) epithelial cells may be a mechanism by which production of a noninducible antimicrobial is increased temporarily during lesion progression and repair. This increased production of AP by hyperplastic cells may protect the lung against further infection until new, fully differentiated epithelial cells are capable of expressing their own inducible array of antimicrobial peptides.

To determine the density of mast cells (MCs) and the extent of substance P (SP) immunoreactivity during initiation and progression of pneumonic pasteurellosis (PP), 18 lambs were inoculated intrabronchially with Mannheimia (Pasteurella) haemolytica or saline, and lung tissue was collected at 1, 15 and 45 days post-inoculation (n=3, each group). Additionally, the left (non-inoculated) contralateral lungs in bacteria-inoculated animals were collected as controls. At 1 day after bacterial inoculation the lungs had typical M. haemolytica lesions. These pneumonic lesions had fewer numbers of MCs and reduced histamine content. Macrophages infiltrating some of the inflamed areas were strongly immunoreactive for SP. At 15 days, MCs remained scarce at sites where lung damage persisted, i.e. pyogranulomatous foci, but were increased in number in areas of interstitial damage. Pulmonary ganglion neurons were strongly immunoreactive for SP. By 45 days the fibrosing changes became more defined as pleural fibrosis, fibrosing alveolitis, alveolar epithelial hyperplasia and bronchiolitis obliterans. These lungs had increased numbers of MCs, but histamine content was not different from saline- and non-inoculated left lungs. Substance P immunoreactivity occurred only in nerves and was scarce and mild. This work demonstrates that MC density decreases initially with PP, but increases with progression of PP. SP fibres tend to be decreased during the initiation and at 45 days of PP, but other cells, such as macrophages and neuronal ganglion cells, produce substance P during progression of PP and thereby constitute an additional source of substance P., (Copyright 2001 Academic Press.)

In the present study we administered dihydrocapsaicin (DHC) to neonatal lambs to deplete C-fibers of neuropeptides. We measured the density of substance P (SP)-fibers in nasal septum to assess the effectiveness of the treatment at 3, 9, and 21 days. The numbers of mast cells in the upper and lower respiratory tract were determined at the same time points and histamine content was determined from lung tissue. DHC treatment depleted SP-fibers for up to the 21 day time point. This depletion was estimated as 85% in comparison with controls. In vehicle-treated lambs, the density of SP-fibers decreased progressively with age, but not to the degree of DHC-treated lambs whose SP-fibers were depleted from the initial 3-day measurement. In both, vehicle- and DHC-treated lambs, numbers of mast cells increased progressively with time; however, the density of mast cells was augmented in the entire respiratory tract of DHC-treated animals. Apparently, DHC treatment exerts a single and initial effect in increasing mast cells whereas time maintains a continuous influence; both factors exert their influence independently. Despite large numbers of mast cells in DHC-treated animals, histamine content in the lung had similar levels as controls. Our study provides fundamental data for a better understanding of conditions that may influence defense mechanisms dependent on the mast cell-nerve axis in the respiratory tract.

Immune complex formation has long been thought to play a role in the pathogenesis of Pasteurella haemolytica pneumonia. This study in laboratory rabbits was designed to investigate immune-mediated damage in respiratory tissue caused by lipopolysaccharide (LPS). Severe lesions were induced by the intratracheal (IT) injection of P. haemolytica A1 LPS (50 micrograms) into rabbits previously immunized with P. haemolytica killed whole cells emulsified with Freund's incomplete adjuvant (FIA); these lesions included perivascular oedema and polymorphonuclear leucocyte (PMN) infiltration of the subintima, with degeneration and necrosis of the media. Smaller vessels were occluded by PMNs in various stages of degranulation. PMN counts in bronchoalveolar lavage (BAL) fluid were significantly elevated (P < 0.05). Lesions were also induced by the IT injection of LPS (50 micrograms) into rabbits pretreated with an emulsion consisting merely of FIA and formol-saline; these lesions included moderate to severe congestion, interstitial oedema, alveolar serofibrinous exudation and PMN infiltration. PMNs were also present in BAL fluid. Rabbits pretreated with FIA in formol-saline and given a later IT injection of saline, and rabbits pretreated with bovine serum albumin (BSA) in FIA and given a later IT injection of BSA, were included as negative and positive control groups. Cutaneous lesions were also induced by the intradermal injection of LPS into rabbits immunized against P. haemolytica and of BSA into rabbits immunized with BSA. Overall, the pulmonary and cutaneous lesions induced in vaccinated rabbits by antigen administration were more severe than those seen in non-vaccinated rabbits. The lesions in rabbits, which were similar to those seen in natural cases of P. haemolytica pneumonia in cattle, were characterized by a fibrinopurulent inflammatory process with extensive interstitial oedema, fibrinous exudate, and PMNs. This model may help to elucidate the pathogenesis of pneumonic pasteurellosis in immunized animals.

Pneumonic pasteurellosis is the major economic problem of the cattle industry in North America. This disease is characterized by an acute, severe, fibrinonecrotic pleuropneumonia. Pasteurella haemolytica A1 is commonly isolated from these pneumonic lesions. It has been demonstrated that stress or viral infection compromises defense mechanisms of the upper respiratory tract and lung, predisposing to an initial multiplication of bacteria in the nasopharynx and, subsequently, lungs are deluged with large numbers of bacteria. Once multiplication in the alveoli has begun, virulence factors exert their influence to induce an excessive host inflammatory response that results in severe tissue damage. Despite a large number of studies conducted to explore the complex interaction between P. haemolytica and the host response, there still remains a lack of detailed understanding. This review discusses evidence of the role of the main virulence factors of P. haemolytica on the pathogenesis of pulmonary damage.