Effect of resistant starch on the intestinal health of old dogs: fermentation products and histological features of the intestinal mucosa.

The effects of resistant starch (RS) intake on nutrient digestibility, microbial fermentation products, faecal IgA, faecal pH, and histological features of the intestinal mucosa of old dogs were evaluated. The same formulation was extruded in two different conditions: one to obtain elevated starch cooking degree with low RS content (0.21%) and the other lower starch cooking with high RS content (1.46%). Eight geriatric Beagles (11.5 ± 0.38 years old) were fed each diet for 61 days in a crossover design. Food intake, nutrient digestibility, fermentation products, faecal pH, and faecal IgA were examined via variance analysis. Histological results of intestinal biopsies were assessed via Wilcoxon test for paired data. The morphometric characteristics of large intestine crypts were evaluated via paired t tests (p < .05). Protein, fat, and energy digestibilities were higher for the low-RS diet (p < .05). Dogs receiving the high-RS diet had lower faecal pH and higher values for propionate, butyrate, total volatile fatty acids, and lactate (p < .05). No differences between diets were found in the histological parameters of the gut mucosa, and only a tendency for deeper crypts in the descending colon was observed for dogs fed the high-RS diet (p = .083). The intake of a corn-based kibble diet manufactured with coarse ground raw material and low starch gelatinization to obtain 1.4% of RS affected microbial fermentation products and faecal pH and tended to increase crypt depth in the descending colon of old dogs.

Tumor estromal gastrointestinal em cães: estudo clínico-anatomopatológico / Gastrointestinal stromal tumors in dogs: a clinicopathologic study

Os tumores estromais gastrointestinais (GIST) são incomuns e apresentam elevada similaridade histológica com as neoplasias de músculo liso e de nervo periférico. Este trabalho relata e caracteriza GIST em cães do ponto de vista epidemiológico, clínico-laboratorial, anatomopatológico e imuno-histoquímico, com base na análise retrospectiva de três cães, machos, com média de idade de 10 anos, variando de porte médio a grande e peso médio de 18.5±6kg. As alterações clínicas foram progressivas e inespecíficas de quadro gastrointestinal crônico, tais como prostração, anorexia, perda de peso e melena. Anemia não regenerativa e leucocitose foram os principais achados laboratoriais. Macroscopicamente, os tumores apresentavam média de 19cm no eixo maior, localizados em jejuno e ceco, com a superfície ulcerada, e exibiam áreas de necrose. Na avaliação microscópica, os casos apresentaram proliferação de células fusiformes, arranjadas em feixes longos densamente celulares, que foram vimentina e CD117 positivas, com diferenciação neural (S100 positivo), muscular (actina e desmina positivas) e anaplásica, cuja morfologia caracteriza neoplasias malignas com sobrevida de um dia a 12 meses. O GIST deve ser um dos diagnósticos diferenciais a serem considerados entre as neoplasias mesenquimais do trato gastrointestinal que acometem cães, e o diagnóstico final necessita de imuno-histoquímica.(AU)

Gastrointestinal stromal tumors (GIST) are uncommon and show high histological similarity with smooth muscle and peripheral neuron tumors. This paper reported three cases of gastrointestinal stromal tumor (GIST) showing its clinical and laboratorial presentation, and gross, microscopical and immunohistochemical features. Clinical signs and symptoms of the animals studied were progressive and characterized by nonspecific chronic gastrointestinal disorders such as depression, anorexia, weight loss and melena. Non regenerative anemia and leukocytosis were the main laboratory findings. Grossly, tumors were 19cm big, ulcerated and with necrotic areas. Microscopically, the tumors were malignant spindle cell proliferation with positivity to vimentine and CD117, with neural (S100+), myogenic (desmine + and smooth muscle actine+) and anaplasic differentiation. GIST should be one of the differential diagnoses to be considered among the mesenchymal neoplasms of the gastrointestinal tract of dogs.(AU)

Molecular detection of chicken parvovirus in broilers with enteric disorders presenting curving of duodenal loop, pancreatic atrophy, and mesenteritis.

Enteric disorders are an important cause of economic losses in broiler chickens worldwide. Several agents have been associated with enteric problems, such as viruses, bacteria, and parasites. In this study, broiler chickens showing signs of enteric disorders were subjected to molecular diagnosis for several viral agents and also for pathological examination for elucidating this problem. Thus, the chickens were screened for avian nephritis virus (ANV), chicken astrovirus (CAstV), avian rotavirus (ArtV), avian reovirus (AReoV), infectious bronchitis virus (IBV), fowl adenovirus group I (FAdV-1), and chicken parvovirus (ChPV). Postmortem examinations revealed a curving of the duodenal loop (J-like appearance) and intestines filled with liquid and gaseous content. Histopathological analysis of the duodenal loop showed pancreatic atrophy, acute mesenteritis, and enteritis. PCR results showed that ChPV was the sole viral agent detected in samples with lesions such as the curved duodenal loop and pancreatic atrophy. Molecular characterization of the nucleotide and deduced amino acid sequences revealed a high similarity with other strains of ChPV from Brazil, Canada, United States, Europe, and Asia. These findings suggest an association between ChPV and the development of enteritis, pancreatitis, and pancreatic atrophy, which may lead to curling of the duodenal loop. Together, these alterations may disrupt the normal functioning of the digestive system, diminishing digestion and the absorption of dietary nutrients and consequently leading to reduced weight gain, flock impairment, dwarfism, and an elevated feed conversion rate.

Virulence and antimicrobial resistance of Klebsiella pneumoniae isolated from passerine and psittacine birds.

Klebsiella pneumoniae is considered one of the most important Gram-negative opportunistic pathogens. The contact between humans and birds poses health risks to both. The aim of this study was to investigate the resistance and virulence of K. pneumoniae isolates from psittacines and passerines, seized from illegal trade in Brazil. We analysed 32 strains isolated from birds of the orders Psittaciformes and Passeriformes by polymerase chain reaction (PCR) for virulence factor genes. Antibiotic resistance was assessed by disk diffusion assay and PCR. The results indicated that fimH (100%), uge (96.8%), kfu (81.2%) and irp-2 (68.7%) were the most common virulence genes, followed by kpn (46.8%), K2 (43.7%), mrkD (34.3%) and iroN (15.6%). The combination of virulence genes resulted in a great diversity of genotypes and the heterogeneity of the strains is also confirmed in the analysis by amplified fragment length polymorphism. The susceptibility profiles of the K. pneumoniae showed 25% of multiple antibiotic resistance strains. We identified seven strains that presented non-extended spectrum beta lactamase blaSHV variants SHV-1 and SHV-11 and one strain positive to the blaTEM-1 gene. Plasmid-mediated quinolone resistance was present in 10 strains (10/32). The data obtained in this study reveal the pathogenic potential of this pathogen and highlight the need for surveillance and monitoring.

Cellulitis lesions in broiler chickens are induced by Escherichia coli Vacuolating Factor (ECVF).

Escherichia coli Vacuolating Factor (ECVF) is a heat-labile, vacuolating cytotoxin produced by avian pathogenic E. coli (APEC) isolated from avian cellulitis lesions. In this report, we intend to demonstrate that purified ECVF induces the inflammatory process of cellulitis. Our group is the first to demonstrate the effect of ECVF in a histological analysis by in situ inoculation of broiler chickens with purified ECVF. The animals were inoculated with the APEC AC53 and with purified ECVF subcutaneously on their ventral surface (in the sternum region). The histological analysis showed different grades of an acute inflammatory response in the epidermis, dermis and panniculus. An increase in mRNA expression of the proinflammatory cytokine TNF-α was also demonstrated in the inflamed tissue. When ECVF was systemically administered, increased levels of TNF-α and IL-10 were observed in the serum. These results suggest that ECVF plays a key role in the inflammatory process associated with cellulitis that is mainly mediated by TNF-α. In addition, this inflammation can be downregulated by the anti-inflammatory cytokine IL-10.

Comparison of ultrasonography and histopathology for the diagnosis of endometritis in Holstein-Friesian cows.

Reproductive diseases are a great barrier to dairy production, as they diminish fertility and cause economic loss. In this context, endometritis plays an important role. Different diagnostic techniques exist for endometritis that vary in sensitivity and specificity. This work aimed to evaluate and compare ultrasonographic and histopathological examinations, and combinations thereof, for the diagnosis of endometritis by determining their sensitivity, specificity, and kappa agreement coefficients using endometrial cytology as the gold standard. We developed an adaptive reading score to perform histological examination of the uterus. In this study, 76 Holstein-Friesian cows, 21 to 47 d postpartum, without vaginal catarrh were submitted to gynecological examinations, including ultrasonographic examination, an endometrial cytology examination, and a uterine biopsy. Our results indicate that ultrasonography is a practical and effective diagnostic method, and a combination of the determination of intrauterine fluid and cervical diameter was the most efficient ultrasonographic method, with 50% sensitivity and 88% specificity. Histopathological examination was a useful diagnostic method that provided rich detail on endometrial inflammation, and allowed evaluation of different components of the tissue such as the epithelium, lamina propria, endometrial glands, and blood vessels; this method had 44% sensitivity and 92% specificity for diagnosis of endometritis.

Acute heat stress impairs performance parameters and induces mild intestinal enteritis in broiler chickens: role of acute hypothalamic-pituitary-adrenal axis activation.

Studies on the environmental consequences of stress are relevant for economic and animal welfare reasons. We recently reported that long-term heat stressors (31 ± 1°C and 36 ± 1°C for 10 h/d) applied to broiler chickens (Gallus gallus domesticus) from d 35 to 42 of life increased serum corticosterone concentrations, decreased performance variables and the macrophage oxidative burst, and produced mild, multifocal acute enteritis. Being cognizant of the relevance of acute heat stress on tropical and subtropical poultry production, we designed the current experiment to analyze, from a neuroimmune perspective, the effects of an acute heat stress (31 ± 1°C for 10 h on d 35 of life) on serum corticosterone, performance variables, intestinal histology, and peritoneal macrophage activity in chickens. We demonstrated that the acute heat stress increased serum corticosterone concentrations and mortality and decreased food intake, BW gain, and feed conversion (P < 0.05). We did not find changes in the relative weights of the spleen, thymus, and bursa of Fabricius (P > 0.05). Increases in the basal and the Staphylococcus aureus-induced macrophage oxidative bursts and a decrease in the percentage of macrophages performing phagocytosis were also observed. Finally, mild, multifocal acute enteritis, characterized by the increased presence of lymphocytes and plasmocytes within the lamina propria of the jejunum, was also observed. We found that the stress-induced hypothalamic-pituitary-adrenal axis activation was responsible for the negative effects observed on chicken performance and immune function as well as for the changes in the intestinal mucosa. The data presented here corroborate with those presented in other studies in the field of neuroimmunomodulation and open new avenues for the improvement of broiler chicken welfare and production performance.

Fiber fermentability effects on energy and macronutrient digestibility, fecal traits, postprandial metabolite responses, and colon histology of overweight cats.

Considering the different potential benefits of divergent fiber ingredients, the effect of 3 fiber sources on energy and macronutrient digestibility, fermentation product formation, postprandial metabolite responses, and colon histology of overweight cats (Felis catus) fed kibble diets was compared. Twenty-four healthy adult cats were assigned in a complete randomized block design to 2 groups of 12 animals, and 3 animals from each group were fed 1 of 4 of the following kibble diets: control (CO; 11.5% dietary fiber), beet pulp (BP; 26% dietary fiber), wheat bran (WB; 24% dietary fiber), and sugarcane fiber (SF; 28% dietary fiber). Digestibility was measured by the total collection of feces. After 16 d of diet adaptation and an overnight period without food, blood glucose, cholesterol, and triglyceride postprandial responses were evaluated for 16 h after continued exposure to food. On d 20, colon biopsies of the cats were collected under general anesthesia. Fiber addition reduced food energy and nutrient digestibility. Of all the fiber sources, SF had the least dietary fiber digestibility (P < 0.05), causing the largest reduction of dietary energy digestibility (P < 0.05). The greater fermentability of BP resulted in reduced fecal DM and pH, greater fecal production [g/(cat × d); as-is], and greater fecal concentration of acetate, propionate, and lactate (P < 0.05). For most fecal variables, WB was intermediate between BP and SF, and SF was similar to the control diet except for an increased fecal DM and firmer feces production for the SF diet (P < 0.05). Postprandial evaluations indicated reduced mean glucose concentration and area under the glucose curve in cats fed the SF diet (P < 0.05). Colon mucosa thickness, crypt area, lamina propria area, goblet cell area, crypt mean size, and crypt in bifurcation did not vary among the diets. According to the fiber solubility and fermentation rates, fiber sources can induce different physiological responses in cats, reduce energy digestibility, and favor glucose metabolism (SF), or improve gut health (BP).

Heat stress impairs performance parameters, induces intestinal injury, and decreases macrophage activity in broiler chickens.

Studies on environmental consequences of stress on animal production have grown substantially in the last few years for economic and animal welfare reasons. Physiological, hormonal, and immunological deficits as well as increases in animals' susceptibility to diseases have been reported after different stressors in broiler chickens. The aim of the current experiment is to describe the effects of 2 different heat stressors (31 +/- 1 and 36 +/- 1 degrees C/10 h per d) applied to broiler chickens from d 35 to 42 of life on the corticosterone serum levels, performance parameters, intestinal histology, and peritoneal macrophage activity, correlating and discussing the obtained data under a neuroimmune perspective. In our study, we demonstrated that heat stress (31 +/- 1 and 36 +/- 1 degrees C) increased the corticosterone serum levels and decreased BW gain and food intake. Only chickens submitted to 36 +/- 1 degrees C, however, presented a decrease in feed conversion and increased mortality. We also showed a decrease of bursa of Fabricius (31 +/- 1 and 36 +/- 1 degrees C), thymus (36 +/- 1 degrees C), and spleen (36 +/- 1 degrees C) relative weights and of macrophage basal (31 +/- 1 and 36 +/- 1 degrees C) and Staphylococcus aureus-induced oxidative burst (31 +/- 1 degrees C). Finally, mild multifocal acute enteritis characterized by an increased presence of lymphocytes and plasmocytes within the jejunum's lamina propria was also observed. The stress-induced hypothalamic-pituitary-adrenal axis activation was taken as responsible for the negative effects observed on the chickens' performance and immune function and also the changes of the intestinal mucosa. The present obtained data corroborate with others in the field of neuroimmunomodulation and open new avenues for the improvement of broiler chicken welfare and production performance.

Oral focal epithelial hyperplasia in a howler monkey (Alouatta fusca).

Oral focal epithelial hyperplasia is a rare and seldom reported disease in animals and humans induced by a papillomavirus. The present report is the first description of this disease in a Neotropical primate, a howler monkey (Alouatta fusca). The diagnosis was based on gross and microscopic findings. The generic papillomavirus antigen was identified by immunohistochemistry and was found not to be related to any human papillomavirus DNA tested by in situ hybridization. This virus is probably a specific papillomavirus of the howler monkey (HMPV).