Poisoning in ruminants caused by species of the genus Cestrum L. (Solanaceae) in Brazil: A review of toxicological and phytochemical evidence

Some plant species of the genus Cestrum L. (Solanaceae family) are known to cause poisoning in farming animals in Brazil, negatively affecting the livestock sector. In this context, this study aimed to carry out a systematic review of the Cestrum species that cause poisoning in ruminants in Brazil and to list the main phytochemicals involved in these toxic activities that have already been identified. Scientific documents were retrieved in Google Scholar, PubMed®, ScienceDirect®, and SciELO databases. After applying the inclusion criteria, a total of 38 articles published between 1920 and 2023 were included in the present study. Cestrum axillare Vell. [Syn. Cestrum laevigatum Schltdl.], Cestrum corymbosum Schltdl., Cestrum intermedium Sendtn., and Cestrum parqui L'Hér. were found to have reported cases of poisoning in the Northeast, Southeast, and South of Brazil. Natural poisonings in ruminants caused by these species have been recorded in ten Brazilian states, mostly in Rio de Janeiro, Santa Catarina, Rio Grande do Sul, and Pernambuco. In general, Cestrum species cause liver damage and a clinical-pathological state characterized by acute liver failure of the poisoned animals. Cattle are more susceptible to poisoning by these plants, but there are reports of poisoning by C. axillare in goats and buffaloes as well. Several chemical constituents were identified in C. axillare and C. parqui, including some saponins and terpenoids that may be associated with the cases of poisoning. However, only one chemical compound has been identified in C. intermedium, and no phytochemical investigation has been carried out regarding toxic compounds in C. corymbosum. It is expected that future studies fill the gap in determining the toxic principles present in these species.

Effect of diets containing commercial bioactive compounds on Salmonella Heidelberg infection in broiler chicks

Salmonella Heidelberg (SH) is responsible for economic losses in poultry farming and food infections in humans and is a serious public health problem. Recently, there has been an increase in the frequency of isolation of this serotype in batches of broilers raised in Brazil. It is necessary to find new ways to help control this pathogen. The present study aimed to evaluate the effect of diets containing the compound Original XPC, which is a prebiotic-like fermented compound (PFC), and/or Sangrovit, which is a sanguinarine-based phytobiotic (SAN), on SH infection in broiler chicks. For this purpose, SH colonization in the cecum and its invasion into the spleen and liver were evaluated, as were the histopathological changes caused in these organs. The lowest cecal SH counts were observed in birds that ingested SAN, followed by those fed PFC (P < 0.05), with no added effect when the two bioproducts were used together (SAN + PFC). The mean SH and liver spleen counts did not differ between groups (P > 0.05). In general, birds from all groups challenged with SH showed similar macroscopic changes, such as hemorrhagic areas, hepatomegaly, and splenomegaly, such changes being more intense in the infected control group. The microscopic changes observed in the liver included hepatocyte congestion, heterophil infiltration in the sinusoid capillaries, areas of necrosis, and mononuclear inflammation. In the cecum, heterophilic infiltrate and thickening of the lamina propria were observed. In the ileum, the most common changes were congestion and thickening of the lamina propria and atrophy of the villi and crypts. The microscopic changes were less intense in the supplemented birds than the infected control group, and those supplemented with SAN developed the least changes. As ideal conditions for histomorphometric parameters of the ileum, the villus:crypt ratio in birds should be high, the villi should be long, and the crypts should be shallow. In the present study, higher mean heights and villus areas were observed in uninfected control and SAN group birds, and the crypt depth was lower in birds in the negative control group. The lowest villus:crypt ratio was observed in the birds of the infected control group. Although additional studies are needed, the preliminary results of the current investigation indicated that the addition of bioproducts, especially SAN, to the diet of birds helped to control SH infection, reducing its count in the cecum and improving overall and intestinal health.

Effects of chronic dietary nitrate supplementation on longevity, vascular function and cancer incidence in rats

RATIONALE

Dietary nitrate and nitrite have a notoriously bad reputation because of their proposed association with disease, in particular cancer. However, more recent lines of research have challenged this dogma suggesting that intake of these anions also possess beneficial effects after in vivo conversion to the vital signaling molecule nitric oxide. Such effects include improvement in cardiovascular, renal and metabolic function, which is partly mediated via reduction of oxidative stress. A recent study even indicates that low dose of dietary nitrite extends life span in fruit flies.

METHODS

In this study, 200 middle-aged Wistar rats of both sexes were supplemented with nitrate or placebo in the drinking water throughout their remaining life and we studied longevity, biochemical markers of disease, vascular reactivity along with careful determination of the cause of death.

RESULTS

Dietary nitrate did not affect life span or the age-dependent changes in markers of oxidative stress, kidney and liver function, or lipid profile. Ex vivo examination of vascular function, however, showed improvements in endothelial function in rats treated with nitrate. Neoplasms were not more common in the nitrate group.

CONCLUSION

We conclude that chronic treatment with dietary nitrate does not affect life span in rats nor does it increase the incidence of cancer. In contrast, vascular function was improved by nitrate, possibly suggesting an increase in health span.

Clinical, imaginological and pathological aspects of umbilical panvasculitis in calves: case report

The diagnosis of umbilical infections in neonates can be obtained from clinical signs, but the intracavitary involvement of structures and associated complications can be underestimated, compromising the establishment of adequate therapeutic approaches or prognosis. This case report presents the clinical, imaging, pathological and microbiological aspects of an umbilical infection in calves. Physical examination of the animal identified apathy, low body score, increased volume in the umbilical region and joints. The abdominal palpation identified firm structures in topography of the arteries and umbilical vein. Imaging examinations of the abdomen and joints were performed. Multiple, hyperechogenic focal structures have been identified in the liver, as well as cylindrical and firm structures in topography of the arteries and umbilical vein. In the joints, osteolytic changes, periosteal reactions, subchondral sclerosis and formation of osteophytes were seen. Umbilical panvasculitis triggered arthritis and an infectious process in the liver, the case being assessed as having an unfavorable prognosis and the animal being referred for euthanasia. At necropsy, multifocal abscesses were observed in the pleura, ribs, omentum, spleen and liver. There was granulomatous exudate in the urinary vesicle. The affected joints presented thickening of the joint capsule with the presence of exudate. In the microbiological analysis of liver fragments, urinary vesicle content and joint exudate, Proteus mirabilis with resistance to antimicrobials was identified. Imaging studies collaborated with the establishment of the prognosis and conduct adopted, and must, whenever possible, be included in the clinical examination. In case of death, necropsy allows a correct association of clinical signs and imaging findings.

Eccrine and Apocrine Carcinoma in Dogs

Background: Sweat gland carcinomas divide into eccrine, apocrine, mixed origin (eccrine and apocrine). Eccrine carcinoma (EC) is a rare malignant neoplasm of the sweat glands that can affect dogs, cats, and humans. EC can present itself as a solitary swelling in the pads, digits, or distal limbs. EC is more common in elder animals, and exhibits no predisposition according to breed. In humans, EC is more frequent in the head and neck, and is more likely to occur in mid-aged people; metastases can develop in any site of the body. A diagnosis of this type of tumor can be determined by histopathological examination. Apocrine carcinomas occur most frequently in the axillary areas even though they may occur in other regions of the body, and affect mainly elder animals.Case: A 13-year-old male mongrel dog with a history of presence of smooth reddish infiltrative nodule in the skin of the thorax, but with no history of progression, was examined. After running complementary tests, a fragment of the skin on the thorax was taken for biopsy. The second animal was an 8-year-old female Golden Retriever, which was presented with a history of presence of a nodule on the right digital pad. After running complementary tests, a fragment of this nodule was collected. In both cases, the excised fragments were placed in 10% buffered formalin and routinely processed for the preparation of histological slides, which were stained with hematoxylin and eosin, and subjected to histopathological evaluation.  Light microscopy analysis revealed, in both cases, the presence of a poorly delimited, non-encapsulated mass infiltrating the muscle and adipose tissue. Necrotic areas, and presence of eosinophilic material in the nucleus were observed. Additionally, the samples from both cases were subjected to immunohistochemical staining for cytokeratin (CK Pan).Discussion: A definitive diagnosis of sweat gland carcinoma was achieved by means of the histopathological analysis. Sweat gland neoplasms are uncommon and difficult to diagnose; distinguishing eccrine carcinoma from apocrine carcinoma requires knowledge on the site of origin of the tumor. Some authors assert that, in spite the growing number of reports on tumors of cutaneous glands in dogs, there are only few immunohistochemical studies on cutaneous gland neoplasms in these animals. There is no specific immunohistochemical marker to distinguish eccrine carcinoma from apocrine carcinoma. Consequently, investigation on the anatomical origin of the tumor is important. In the cases describe herein, involvement of the thorax (apocrine) and digital pad (eccrine) are reported. However, there are accounts of the occurrence of sweat gland tumors in axillary and inguinal regions, as well as in the limbs. Both biopsy samples tested positive for cytokeratin (CK) after immunohistochemical examination. This marker is specific for simple epithelium and, according to some authors, can distinguish an eccrine carcinoma from basal cell carcinoma. The antibody used did not stain the innermost are of the tumor, where cells may be negative for CK. Some tumors may not have specific markers, which makes a combination of clinical data and complementary histopathological and immunohistochemical exams necessary for the determination of a diagnosis, as is the case for eccrine and apocrine carcinomas. In view of the scarcity of reports on eccrine carcinoma in the literature, and considering the small number of immunohistochemical studies on cutaneous gland tumors in dogs and cats, this work can help the determination of the diagnosis of cutaneous neoplasms, which are frequently observed in the clinical routine.

Progressive Histiocytosis of Non-Epitheliotropic Dendritic Cells in a Feline

Background: Histiocytic tumors in felines are nodules that commonly develop on limbs and head extremities. They can be divided into many subtypes including cutaneous histiocytoma, histiocytic sarcoma, reactive fibrohistiocytic nodule, Langerhans cell histiocytosis, and progressive feline dendritic cell. Despite the same origin, they have behaviors that differ from each other, thus it is important to confirm diagnosis with histopathological and immunohistochemical tests, because early identification can facilitate prognosis and treatment. In this study, we describe the pathological and immunohistochemical characteristics, enabling differentiation feline neoplasms derived from histiocytes. Case: A 5-year-old, crossbreed, male, feline presented with a nodulation at the base of the left ear. The mass was slow growing, partially alopecic, with no other changes associated with tumor development. The nodule was round and circumscribed, movable, with an elevated surface. He was referred for surgery and an elliptical sample around the tumor was carefully dissected. Routine histopathological evaluation was performed with hematoxylin and eosin (HE), as well as immunohistochemistry. Histopathology showed circumscribed proliferation of histiocytic cells, with abundant and eosinophilic cytoplasm. The proliferative cells were large and rounded, extending from the superficial dermis and basement membrane to the deep dermis. At the extremities, some cells had visible vacuoles. Mitotic activity ranged from 3 to 4 mitoses per field in 40x magnification. Immunohistochemistry showed positive staining for histocompatibility complex MCII and lysozyme antibodies, marking histiocytic cells. Labeling was positive for CD20 in cells of lymphoid lineage B and negative for E-cadherin. Histiocytic cells did not invade the epidermis; hence, proliferation was classified as nonepitheliotropic. These methods contribute to the literature regarding the diagnosis of this rare tumor. Therefore, histological as well as immunohistochemical evaluation are important bfor confirming clinical diagnosis of histiocytic proliferation non-epitheliotropic. Discussion: Progressive histiocytosis of feline dendritic cells, in both epitheliotropic and non-epitheliotropic forms, is considered a clinically progressive and rare disorder. There are reports which include cytological, clinical, histological and immunohistochemical examinations, but the diagnostic characteristics regarding the non-epitheliotropic classification have not yet been properly identified. Nodulations are predominantly observed in head and limb regions, usually non-ulcerated, which can both increase and decrease in size, and are typically painless. The tumor in the present case was restricted to the base of the ear and no evidence of infiltration or metastasis was found. Progressive histiocytosis may spread and reach the lymphatic system through the lymph nodes, subsequently becoming systemic. The non-aggressive behavior observed in this case is possibly related to the non-epitheliotropic pattern. In the present case, MHC II histocompatibility complex markers, a phenotype compatible with dendritic cells, were used. Lysozyme antibodies marked histiocytic cells and the reactive lymphoid infiltrate was composed of CD20-positive B lymphoid lineage cells. Staining for E-cadherin was negative, negative results in labeling experiments is common, it is dependent upon the cellular origin of the leukocytes present in the sample. Staining for these molecules is recommended for differentiating feline progressive histiocytosis from Langerhans cells. Langerhans cells can be characterized by E-cadherin expression in about 10% of cases and marked T lymphocyte and neutrophil expression in the affected tissue. In this case, the histopathological exam along with immunohistochemistry was essential for differentiating them.

Determination of baseline values for routine ophthalmic tests in bearded capuchin (Sapajus libidinosus)

BACKGROUND

Establish baseline values for ophthalmic diagnostic tests in Sapajus libidinosus.

METHODS

Ophthalmic diagnostic tests, namely Schirmer tear test 1 (STT-1), intraocular pressure (IOP), B-mode ultrasound, culture of the bacterial conjunctival microbiota, and conjunctival exfoliative cytology, were performed in 15 S. libidinosus.

RESULTS

Mean values found were as follows: 2.50 ± 2.94 mm/min for the STT-1; 13.3 ± 3.32 mm Hg for the IOP; 2.47 ± 0.41 mm for the depth of the anterior chamber; 2.86 ± 0.96 mm for the axial length of the lens; 10.97 ± 0.48 mm for the depth of the vitreous chamber; and 16.32 ± 1.24 mm for the axial length of the eyeball. The bacterial genus most frequently found was Staphylococcus spp. Conjunctival cytology showed intermediate epithelial, squamous superficial epithelial, and keratinized cells.

CONCLUSIONS

Determination of baseline values for eye measurements and ophthalmic tests will assist in the diagnosis of eye diseases in S. libidinosus monkeys.