Geferson Fischer

Desempenho de Frangos de Corte Alimentados com Dietas à Base de Milho e Farelo de Soja, com ou sem Adição de Enzimas

This study was run to evaluate the effect of inclusion of an enzymatic cocktail, containing proteases, amilases and cellulases (Vegpro) in broiler diets. The cocktail was added with the ration of 1 kg per 200 kg of soybean meal. Two thousand and forty female Ross chicks were distributed in eight treatments with seven replicates each. A split-plot experimental design was used. Treatments consisted of T1 ¾ control (no enzyme added), T2 ¾ diet five percent lower in energy, protein and [...]

Avian IgY antibodies: characteristics and applications in immunodiagnostic

Immunoglobulin Y (IgY) is the major antibody isotype in birds, reptiles, amphibia, and lungfish, playing a similar biological role as mammal IgG. Due to its phylogenetic distance, immune diversification and presence in the egg yolk, IgY provide a number of advantages in immunodiagnostic compared to IgG from mammals. Moreover, IgY production is in agreement with international efforts to reduce, refine and if possible, to replace animals in experimentation, contributing substantially in favor of animal welfare. This article presents an overview about structural and functional features, production and applications of IgY in immunodiagnostic, as well as the advantages of chicken antibodies use.

Avian pox virus infection in a common barn owl (Tyto alba) in southern Brazil

A young common barn owl (Tyto alba) was referred to the Nucleo de Reabilitacao da Fauna Silvestre (Nurfs), Federal University of Pelotas (UFPel), after been found in a barn of a brick factory in the urban area of Pelotas, Rio Grande do Sul, Brazil. The bird was apathic, weak and with crusty lesions in the featherless areas (eyes, beak, legs), and died soon after arrival at Nurfs. Necropsy and histopathological examination of the lesions were carried out. The hyperplasia and hypertrophy of the cutaneous lesions, several eosinophilic intracyto-plasmic inclusion bodies in epithelial cells (Bollinger bodies), as well as particles characteristic of poxvirus, observed by electronic microscopy, confirmed the infection by avian poxvirus, what highlights the importance of Tyto alba as carrier of the virus in the wild.

The immune modulation of Bacillus cereus var. Toyoi in mice immunized with experimental inactivated Bovine Herpesvirus Type 5 vaccine

In recent years, there been significant progress toward develop more efficient vaccines. Different compounds with adjuvant capacity have been tested; however, no compound has emerged that suitable for universal use. Several efforts have been made to produce effective vaccines against Bovine herpesvirus 5 (BoHV-5), an important cattle pathogen. In this study we examine the use the probiotic Bacillus cereus var. Toyoi as a potential adjuvant to improve BoHV-5 vaccine efficacy. We observed in the supplemented animals a systemic enhanced IgG antibody response toward Th1, and increased IFN-γ, IL-12 and IL-10 cytokines mRNA levels. These results suggest that this probiotic could provide a promising means of improving vaccine efficacy, particularly those vaccines that rely on a cell-mediated immune response.

Immune responses of mice against recombinant bovine herpesvirus 5 glycoprotein D.

Glycoprotein D (gD) is essential for attachment and penetration of Bovine herpesvirus 5 (BoHV-5) into permissive cells, and is a major target of the host immune system, inducing strong humoral and cellular immune responses. The aim of this study was to evaluate in mice the immunogenicity of recombinant BoHV-5 gD (rgD5) expressed in Pichia pastoris. Vaccines formulated with rgD5 alone or adjuvanted with Montanide 50 ISA V2; Emulsigen or Emulsigen-DDA was administered intramuscularly or subcutaneously. Almost all formulations stimulated a humoral immune response after the first inoculation. The only exception was observed when the rgD5 was administered subcutaneously without adjuvant, in this case, the antibodies were observed after three doses. Higher titers of neutralizing antibodies were obtained with the three oil-based adjuvant formulations when compared to non-adjuvanted vaccine formulations. The rgD5 vaccine stimulated high mRNA expression levels of Th1 (INF-γ) and pro-inflammatory cytokines (IL-17, GM-CSF). The results demonstrated that the recombinant gD from BoHV-5 conserved important epitopes for viral neutralization from native BoHV-5 gD and was able to elicit mixed Th1/Th2 immune response in mice.

Antiviral activity of a Bacillus sp: P34 peptide against pathogenic viruses of domestic animals

P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2), canine coronavirus (CCoV), canine distemper virus (CDV), canine parvovirus type 2 (CPV-2), equine arteritis virus (EAV), equine influenza virus (EIV), feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1). The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 104.5 TCID50 to 102.75 TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections.

Serum survey for antibodies to coronavirus, herpesvirus, calicivirus, and parvovirus in domestics cats from Rio Grande do Sul, Brazil.

In Brazil, data regarding the occurrence of feline infections by Feline coronavirus (FCoV), Feline herpesvirus (FHV-1), Feline calicivirus (FCV), and Feline parvovirus (FPV) are scarce (Weiblen et al., 1988; Oliveira et al., 2003; Ruthner et al., 2005), and to this moment there are no scientific reports made in the region of Pelotas, RS, Southern Brazil. FCoV is associated to the development of mild enteritis (Vennema et al., 1998; Hartmann, 2005) or, when FCoV mutants are originated, it can lead to the development of a feline infectious peritonitis (FIP), a progressive systemic disease with a wide spectrum of clinical signs and high mortality rate (Hartmann, 2005). FHV-1 and FCV are agents causing mainly upper respiratory tract diseases, but cats can be infected by these agents without showing clinical signs and become persistent carriers (Maggs et al., 1999; Radford et al., 2007). FPV is highly contagious, inducing an acute disease characterized by leukopenia, fever, depression, dehydration, diarrhea, and vomiting (McKnight et al., 2007). The present study investigated the presence of antibodies against FCoV, FHV-1, FCV, and FPV in the serum samples of 97 domestic cats from Pelotas, Rio Grande do Sul, Southern Brazil. The antibody frequency was analyzed regarding information about age, gender, and habitat that would allow contact with other animals. Serum samples were collected from animals that would be submitted to elective surgeries at the Veterinary Hospital at the Universidade Federal de Pelotas, RS and in five private clinics from the region, from August 2005 to October 2006. Blood samples were collected by cephalic or jugular vein puncturing and sent to the virology and immunology laboratory of UFPel where they were centrifuged for serum separation. The sera were submitted to serum neutralization test (SN) according to Hohdatsu et al. (1999), with a few modifications. Serum serial dilutions from 1:4 to 1:256 were incubated with 100 TCID

Níveis de anticorpos contra o vírus da cinomose canina e o parvovírus canino em cães não vacinados e vacinados

Antibody titres to canine distemper virus (CDV) and canine parvovirus (CPV) were measured in 132 dogs: 80 had been vaccinated at least once, 22 had not been vaccinated, and 30 had unknown vaccination history. Serum antibody titers were measured by means of serum neutralization (CDV) or hemagglutination inhibition (CPV). Serum CDV titers >20 and serum CPV titers >80 were considered protective. Protective antibodies to CDV were present in 40.1% of the population: 39.8% of the vaccinated dogs, 31.8% unvaccinated, and in 46.6% of the dogs with unknown vaccination history. Protective antibodies to CPV were present in 90.9% of the dogs: 93.7% of the vaccinated dogs, 90.9% of the unvaccinated, and 83.3% of the dogs with unknown vaccination history.

PROPOLIS: A NATURAL PRODUCT AS AN ALTERNATIVE FOR DISINFECTION OF EMBRYONATED EGGS FOR INCUBATION

During the cooling process of embryonated eggs, there is a natural air flux from the surface to the inner part of the eggs, carrying contaminants such as bacteria and fungi through the shells pores, infecting embryos and resulting in the inability to hatch or poor chick quality. Formaldehyde, a toxic product, is still the most used disinfectant for embryonated eggs in the aviculture industry. In order to evaluate the antimicrobial activity of the green propolis ethanolic extract as an alternative to formaldehyde, 140 hatching eggs from laying hens were collected and submitted to disinfection with five different treatments: T1 - without disinfection; T2 - formaldehyde fumigated eggs; T3, T4 and T5 disinfection by immersion in propolis solution in the concentrations of 2,400 µg, 240 µg and 24 µg, respectively. The contamination levels by total mesophiles and fungi of the egg shells (Aspergillus sp. and other moulds) after disinfection with propolis were lower than when compared to the control without disinfection. In comparison with formaldehyde, the 240 µg and 24 µg propolis concentrations did not differ regarding antibacterial activity, but for antifungal activity the 2,400 µg and 240 µg concentrations were more efficient. The 2,400 µg and 240 µg propolis treatments presented a hatching rate of 94.1%, compared to only 84.6% for the formaldehyde treatment. The green propolis ethanolic extract presented antibacterial and antifungal activities in embryonated eggs showing that it can be a new natural disinfectant product substituting formaldehyde.

PEROXIDASE-LINKED ASSAY FOR DETECTION OF ANTIBODIES AGAINST BOVINE LEUKOSIS VIRUS

A peroxidase linked assay (PLA) was designed to screen bovine sera for the presence of specific antibodies against bovine leukosis virus (BLV). Out of 201 samples of bovine sera analyzed, 52.2% were considered positive by PLA, 26.4% by AGID, and 38.9% by ELISA. Western blotting analyses excluded 27 samples found to be positive by PLA. PLA showed 100% of sensitivity when compared with AGID and ELISA. Specificity was 64.8% and 78%, respectively (kappa coefficients were 0.70 and 0.83). These findings indicate that PLA can be used as an alternative method for the diagnosis of BLV infection in cattle.