Experimental infection of commercial layers using a Salmonella enterica sorovar Gallinarum strain: Blood serum components and histopathological changes

The purpose of the study was to evaluate the blood serum components and histopathological findings of commercial layers experimentally infected with Salmonella Gallinarum (SG), the microorganism responsible for the fowl typhoid. 180 commercial layers were distributed into three groups (G): G1 and G2 received 0.2mL of inoculum containing 3.3x10 8 and 3.3x10 5 CFU of resistant SG to the nalidix acid (Nal r)/mL, respectively, directly into their crops; G3 did not receive the inoculum (control group). The birds were inoculated when they were 5 days old and the euthanasia was performed 24 hours before and after infection and 3, 5, 7 and 10 days after the administration of the inoculum. In each day of collection, blood samples were obtained for biochemical tests of the blood serum besides macroscopic and histopathological examination of the birds. Data were submitted to analysis of variance by the SAS statistical program and the means were compared by Tukeýs test (P<0,05). In the serum biochemical profile it was observed that the infection interfered in the values of total protein, albumin, calcium, phosphorus, cholesterol, triglycerides, GGT and ALT in the infected groups. The macroscopic examination showed hepatomegaly, alteration of the hepatic color and hemorrhagic spots in the kidneys of animals from G1. The histopathology showed degeneration of hepatocytes in G1 and G2 although other lesions like multifocal hepatic necrosis and inflammatory infiltrate on the liver and kidneys were restricted to G1. The alterations were more evident on G1 which received a higher concentration of bacteria/mL when compared to G2. The results showed that the correlation between biochemical alterations and macroscopic and histopathological lesions can assist the comprehension of the pathophysiology of fowl typhoid, supplying important information for the diagnosis and prognosis of this disease.

Intravascular lymphomatosis in the central nervous system of dogs: Immunohistochemical investigation in two cases

We report here two postmortem cases of dogs with intravascular lymphomatosis affecting the central nervous system. Intravascular lymphomatosis is represented by an exclusively intravascular proliferation of neoplastic lymphoid cells. To characterize the origin of the neoplastic cells, we have proceeded with immunohistochemical analysis to identify B and T lymphocytes and endothelial cells. The results showed predominance of cells from the T cell lineage, and no evidence of B cell origin was found. Few cells from one dog also exhibited cytoplasmatic staining for vimentin and Von Willebrand factor. Although in one case some immunophenotype diversity was observed, the massive presence of CD3 positive cells confirmed these neoplasms as intravascular lymphomatosis of T cell origin.

Canine transmissible venereal tumors: Aspects related to programmed cell death

Canine transmissible venereal tumor (CTVT) is a neoplasm transmitted by the physical transfer of viable tumor cells by direct contact with injured skin and/or mucous tissue. These cells can transpose across histocompatibility barriers into unrelated hosts. This review focuses on the biology of apoptosis and the interaction of proteins involved in this process, as well as p53, p63 and the antiapoptotic protein Bcl-2. As such, this disease offer unique opportunity to study the biology of transplantable tumours and the interaction of proteins involved in apoptosis process and the prognosis of CTVT.

Poult intestinal organ culture for propagation of Turkey coronavirus and assessment of host-virus interactions

Infection of young poults with turkey coronavirus (TCoV) produces a syndrome characterized by acute enteritis, diarrhea, anorexia, ruffled feathers, decreased body weight gain and uneven flock growth. The objective of this study was to standardize an intestinal organ culture (IOC) in order to assess host-virus interaction related to apoptosis. For this purpose the Brazilian strain (TCoV/Brazil/2006 with GenBank accession number FJ188401), was used for infection. Infected IOC cells had mitochondrial dysfunction and initial nuclear activation with MTT value of 90.7 (± 2.4) and apoptotic factor 2.21 (± 2.1), considered statistically different from uninfected IOC cells (p > 0.05). The kinetics of TCoV antigens and viral RNA was directly correlated to annexin-V, caspases- 2 and -3, p53, BCl-2 antigens at 24, 72 and 96 h post-infection (p.i.). Morphological and biochemical features of apoptosis, such as in situ nuclear fragmentation (TUNEL and annexin-V) and DNA ladder formation were also detected in infected cells at all assayed p.i. intervals. Moreover, different from other coronaviruses, the expression of both effective caspase-2 and - 3 and p53 antigens were considered lower. However, at all p.i., the BCl-2 antigens were expressed quantitatively and qualitatively as viral antigen measured by immunofluorescence microscopy analysis. Because the diagnosis of TCoV infection is only performed by infecting embryonated poult eggs, the pathological characteri tics related to host-virus interaction remain unclear. This is the first report on apoptosis of TCoV infected IOC, and reveals that it may be useful immunological method to assess virus pathogenesis.

Use of rubber tree (Hevea brasiliensis) latex biomembrane in diaphragmatic injuries in rabbits - an experimental study

The aim of this study was to evaluate the surgical use of the natural latex biomembrane in diaphragmatic injuries produced experimentally in rabbits. Fifteen healthy adult male and female New Zealand rabbits were employed. The rabbits were assigned to the experimental groups I, II, III, IV and V and analyzed on the 15th, 30th, 45th, 60th and 90th days post surgery, respectively. The surgical procedure consisted in the access to the diaphragm at the eighth right intercostal space, removal of a circle portion of approximately 1.5 cm in diameter following surgical repair with a latex membrane. Macroscopically, it was observed an excellent healing process during the experimental period. The clinical observations, complemented by the histological analysis, indicate that the latex membrane is useful for repair of traumatic inuries of the diaphragm of rabbits.

Involvement of organic systems in golden retriever X-linked muscular dystrophy

Duchenne muscular dystrophy is a lethal genetic disease characterized by progressive muscle degeneration that usually had been used the Golden Retriever as a model for studying the disease (GRMD - Golden Retriever Muscular Dystrophy). A total of 16 male dystrophic Golden Retrievers dogs between 5 to 51 months of age were examined in the present study. The animals were classified as dystrophic according to two simultaneous complementary criteria: genotypic analysis and serum creatine kinase levels. The macroscopic abnormalities of the different organs and tissues and histopathological features were described using hematoxylin-eosin. The lesions in the skeletal muscles associated with the digestive problems resulted in cachexia with different intensities in all the dystrophic dogs. Cardiac muscle involvement was found in 87,5% of the GRMD dogs resulting, however, in cardiac failure in only 18,8% of the animals. The musculature of the diaphragm was hypertrophic in all affected animals resulting in progressive respiratory muscle weakness and at later stages in respiratory failure (81,25%). The liver abnormalities found in dystrophic dogs were originated mainly from heart disease and developed progressively. Hyperemia of mucosa and granular material indicated changes in the functioning and emptying of bladder. The germinative lineage cells presented moderate to severe degeneration probably due to degeneration of the scrotum and cremaster muscle which prevented the proper thermo-regulation of the testicle. Our results highlight the fact that there is significant impairment of the cardiac, respiratory and skeletal muscle systems in GRMD dogs since the age of five months. In addition, significant alterations of the gastrointestinal tract, urinary and reproductive systems are indicating the presence of degenerative lesions in the smooth musculature.

Evaluation of intracellular calcium in golden retriever muscular dystrophy

The present study had the objective of evaluating calcium accumulations in muscle fibers and their correlation with the canine muscular dystrophy. After the deaths of the animals (13 dystrophic and 3 non-dystrophic), samples of the skeletal muscles were collected. The material was stained with hematoxylin-eosin, Gomori's modified trichrome and alizarin red S technique (pH 4.3). The histopathological changes were analyzed and the proportions of calcium-positive (CPF) and negative muscle fibers were evaluated. Histopathological changes such as muscle fiber diameter changes, necrosis, hyalinization, presence of inflammatory infiltrate and fatty atrophy were identified in all the dystrophic muscles. Statistically significant differences in numbers of CPF between dystrophic muscles and non-dystrophics were observed for the masseter (6%), brachial biceps (5%) and triceps, sartorius and femoral biceps (4%) muscles. The identifying calcium is of interest as a parameter for helping in diagnostic screening.

Bovine abortion associated with Neospora caninum: Diagnosis and epidemiological aspects of a dairy cattle herd in the northeast region of São Paulo state, Brazil

The objective of this study was to report the presence of Neospora caninum-associated abortion in bovines at a farm in the northeast region of São Paulo State. In January 2010, it was sent to the Department of Pathology, UNESP-Jaboticabal, a bovine fetus with an estimated age of seven months, which was natural of a dairy farm with 300 animals and an average daily production of 3,000 liters of milk, nearly 20 liters per cow. The animals were vaccinated against rabies, foot and mouth disease, carbuncle, brucellosis, leptospirosis, bovine herpes virus type I and bovine viral diarrhea virus. The herd consisted of purebred Holstein animals, Jersey, and mostly by crossbred animals 7-8 (gir x holstein). During necropsy, samples of the serosanguineous liquid present at the thoracic cavity and the heart of the fetus were collected for the detection of anti-Neospora caninum antibodies through Indirect Immunofluorescence Assay (IFA). Fragments of brain, cerebellum, tongue, liver, heart and kidneys were collected for the execution of histopathology (HP), immunohistochemistry (IHC) and Polymerase Chain Reaction. In order that IFA could be performed, the owner was requested blood samples without anticoagulants of the mother and other cows in the farm, with or without a history of abortion. At necropsy, it was verified a severe autolysis of the fetus. The serology of the fetus was 1:25, while the serology of the mother was 1:3,200. At HP, it was observed discrete multifocal non-suppurative encephalomyelitis characterized by gliosis and mononuclear inflammatory infiltration associated with cellular debris. DNA amplification of N. caninum was positive in fragments of brain, tongue, cerebellum, heart and kidneys. At IHC, it has been observed immunoreactivity to a cyst located in the tongue. The owner reported that his herd showed endemic episodes of abortion, while 27.69% (18/65) of the 65 animals sampled were seropositive. Although it has not been a significant difference (p>0.05), a higher seropositivity was observed in animals with a history of abortion (10/26) 38.46%, in comparison with animals without previous abortion (8/39) 20.51%. These findings show that the abortion under study was provoked by the protozoan N. caninum, while this is the first report concerning cattle in the northeast region of São Paulo State.

Renal cell carcinoma with cutaneous metastasis in a dog

The present report describes the occurrence of skin metastasis in a dog with primary renal carcinoma. The clinical findings included progressive weight loss, inappetence, palpable abdominal mass and cutaneous nodules. The histopathological examination was carried out after unilateral nephrectomy and was confirmed by immunohistochemistry. The immunohistochemical and histopathological findings characterized this case as renal cell carcinoma with skin metastasis.

Consensus for the diagnosis, prognosis and treatment of canine mammary tumors

The purpose of this paper is to establish criteria that could guide the diagnosis, prognosis and treatment of canine mammary neoplasias. It was elaborated during the Mammary Pathology Meeting: Diagnosis, Prognosis and Treatment of the Canine Mammary Neoplasm, held on November 6 th and 7 th, 2010 in Belo Horizonte - MG, Brazil, sponsored by the Laboratory of Comparative Pathology - UFMG, with the support of the Brazilian Association of Veterinary Pathology (ABPV) and Brazilian Association of Veterinary Oncology (ABROVET). Academics from several regions of Brazil were present and contributed to this work.

Capillary blood glucose and venous blood glucose measured with portable digital glucometer in diabetic dogs

This study aimed to compare the glycemic values obtained with a glucometer with those determined by a colorimetric enzymatic assay in venous blood as well as to evaluate the possibility of using capillary blood samples of dogs with diabetes mellitus. A group with 30 diabetic dogs was formed and from each dog three blood samples were obtained for glycemic evaluations by different methods and blood collection sites. The mean glycemic values showed no significant difference between the different sites of blood collection and methods (P=0.90). Venous, pinna and carpal pad blood glucose showed excellent correlation with the colorimetric enzymatic assay (r=0.98; r=0.95 and r=0.96 respectively) and the obtained values fit properly the clinically acceptable intervals in the error grid analysis. The present study revealed that carpal pad, venous and pinna glucose measurements are clinically acceptable and this method is feasible for use in hospitalized diabetic dogs. The sample attainment of carpal pad proved to be effective and a viable alternative. Further work is necessary to assess the utility of this technique in a home environment.

Relevance of Chinese goose (Anser cygnoides) in experimental epidemiology of Newcastle disease

This study aimed to characterize the true epidemiological role played by the Chinese goose (Anser cygnoides) as a potential source of infection by the Newcastle disease virus (NDV). For this, Specific-Pathogen-Free chicks (SPF) were used and were housed with Chinese geese that had been inoculated with a pathogenic strain (velogenic viscerotropic, strain São João do Meriti) of NDV (DIE50=108.15/0.1 mL) pathogenic to chickens, by the ocular-nasal route. Each group was composed of 6 SPF Leghorn chicks and 3 geese. At 6 days (Group I) and 14 days (Group II) after inoculation of the Chinese geese with NDV, SPF chicks were put into direct contact with each goose group. Cloacal swabs were collected from both species (Chinese geese and SPF chicks) 6, 10 and 20 days after challenge to genome viral excretion by Reverse Transcription Polymerase Chain Reaction (RT-PCR). Chinese geese did not demonstrate any clinical signs of Newcastle disease (ND). They were refractory to the clinical disease with the NDV. However, NDV genome was detected 20 days after challenge. Therefore, NDV carrier status was demonstrated by Chinese geese. Moreover, 100% of SPF chicks housed with the infected Chinese geese had died by 6 (Group I) and 14 days (Group II) after challenge. Thus, the transmission of the pathogenic virus from the Chinese geese to cohabiting SPF chicks was evident within 20 days of the experimental infection. This reveals the epidemiological importance of Chinese geese as a potential transmitter of NDV infection to other commercial birds that could be raised in close proximity.

Immunophenotyping of thymic lymphoma in a Nelore cow

Thymic lymphoma is a malignant lymphoid neoplasm that affects several species, including cattle. This type of neoplasia can lead to death due to malignant cell infiltration in different organs. The classification of this neoplasm may predict prognosis and response to treatment. Immunophenotyping is one of the ways to perform this classification. There are reports about the performance of immunohistochemistry (IHC) to classify thymic lymphoma only in taurine cattle, therefore the aim of this report is to describe the immunophenotype of a thymic lymphoma in a Nelore cow. Immunostaining was performed with monoclonal antibodies (CD79, CD4 and CD8). The tumor cells showed positive staining only for CD8 T lymphocytes, coinciding with the disease progression, since the T lymphoma type is more aggressive.