ABSTRACT Normal passerines (n=216) were evaluated for oocysts of Isospora in feces at the Triage Center for Wild Animals (CETAS, IBAMA, Belo Horizonte; August 21 to September 21, 2012). The positive samples with oocysts represented 13.0% of Cardinalidae (n=23), 11.2% of Emberizidae (n=107), 50% of Icteridae (n=10) and 60.3% of Thraupidae (n=68). The probability of fecal oocysts attributable to the host in Thraupidae is higher than in Cardinalidae, Emberizidae, Fringillidae and Turdidae, but similar to Icteridae. No oocysts were found in Fringillidae and Turdidae. Within Thraupidae, Isospora was for the first time described in Paroaria dominicana and Schistochlamys ruficapillus and within Icteridae, in Gnorimopsar chopi. Saltator similis presented a higher risk, 66.9% greater than Lanio pileatus and Sporophila caerulescens and with a 27.9% greater probability than Sporophila nigricolis. The new coccidian species described were Isospora dominicana [ellipsoid oocysts, 25 (30-20) x 25 (28-20) µm] in Paroaria dominicana; Isospora beagai [ovoid oocysts, 28 (32-17) x 25 (29-16) µm] and Isospora ferri [ellipsoid oocysts, 20 (22-16) x 18 (22-15) µm] in Saltator similis; Isospora ruficapillus [spheric to subspherical oocysts, 25 (26-23) x 24 (25-21) µm] in Schistochlamys ruficapillus; and Isospora chopi [spherical to sub-spherical oocysts, 24.5 x 22 (30-20 x 25-20) µm] and Isospora gnorimopsar [sub-spherical to ovoid oocysts, 27 x 23 (32-22 x 28-20) µm] in Gnorimopsar chopi. The morphometry and features were compared with previously described Isospora in passerines. New coccidian species and new passerine hosts are described for Isospora and recommends for constant monitoring during rehabilitation, especially for the hosts of Thraupidae and Icteridae.

ABSTRACT Salmonella Heidelberg (SH) has represented a great concern to the Brazilian poultry industry in the last years. It is known that immunosuppression in poultry is a contributing factor to increase Salmonella faecal shedding and to disturb control programmes. Not only infectious bursal disease (IBD) virus but also some live vaccines have been reported to induce immunosuppression. In the present study we assessed the effects of two live vaccines against IBD on SH-infected broiler chicks. At 7 days of age, birds of three groups (vaccinated with recombinant HVT-IBD vector, with immune complex-IBD vaccine and unvaccinated) were orally challenged with 1 x 108 CFU of SH. A group of hatchmates remained unvaccinated/unchallenged to serve as negative controls. Caecal colonization and systemic invasion were evaluated by bacterial enumeration at 1, 3, 5, 7 and 14 days post-infection (Dpi) and SH faecal shedding assessed by cloacal swabs at 3, 7, 10 and 14 Dpi. The counts of SH in caecal contents were higher in birds vaccinated with immune complex-IBD than in those that received the HVT-IBD vector vaccine at 5, 7 and 14 dpi (p<0.01). There were no statistical differences in bacterial counts in liver and spleen among birds of different groups. Cloacal swabs also indicated that the birds vaccinated with immune complex-IBD shed more SH than those vaccinated with HVT-IBD vector or those unvaccinated (p<0.01). The results of the present study suggested that the immunosuppressive effect of the immune complex-IBD vaccine helped to increase the SH-faecal shedding in the infected birds.

ABSTRACT Industrial broilers raised on helminthic medication-free feed were diagnosed with a severe disease caused by Ascaridia galli, characterized by intestinal hemorrhage and obstruction. A. galli was identified based on the morphological features of the nematode. Broilers were raised for a longer period (63 days) for weight recovery, grouped as stunted (n=500), had low body score and had fetid diarrhea. The duodenum-jejunum segment was the most severely affected with obstruction and had localized accumulation of gas. The intestinal mucosa was severely congested with petechial and suffusive hemorrhages. The outbreak resulted in morbidity of about 10% and mortality of up to 4% and was associated to the absence of preventive medication on feed and slack biosecurity. The reemergence of A. galli is discussed in view of the alternative poultry management and raising conditions for drug free and welfare.

ABSTRACT Marek’s disease virus (MDV) has been shown to be evolving to higher virulence. One of the genetic sites involved in virulence which enables such characterization is the 339-amino acid Meq protein encoding gene (meq). The reemergence of clinical Marek’s disease (MD) in vaccinated flocks can be associated to changes in meq. Our studies have shown the presence of very virulent MDV strains in the Brazilian industrial and free-range poultry. We present an overview of MD increasing severity and indicate the necessity of using phylogenetic tools for best accompanying MDV evolution.

ABSTRACT Serum samples (n=687) from Gallus gallus domesticus were collected for the investigation of antibodies to avian influenza virus (AIV-A) in the family poultry of the surrounding counties of Santa Maria/RS and the metropolitan region of Belo Horizonte/MG, totaling twenty different counties. Additional samples of seventeen (n=17) free-flying ducks (C. moschata pure or hybrid with Anas platyrhynchos) were collected in Belo Horizonte. The chosen tests for the survey were performed as described by the World Organization for Animal Health (OIE), including agar gel immunodiffusion (AGID) for antibodies to AIV-A nucleoprotein (N) and haemagglutination- inhibition (HI) for antibodies to subtype H1. Out of the 704 serum tests performed by AGID, eight (8/704) were revealed positive for antibodies to AIV-A N protein, with six (6/704) retested positive for subtype H1. Two sera tested positive by AGID were shown to be non reactive to the H1 subtype, suggesting specificity to another subtype. A low occurrence of antibodies to influenza A (1.13%) was found, and mostly (75%) specific to subtype H1. This represents an approximately 0,85% overall occurrence for subtype H1 antibodies, with an unknown subtype specific antibodies detected in one free-flying anatid. The low occurrence of antibodies in the family poultry may suggest a low AIV-A activity during the period of study, information which remains to be confirmed by virus detection.

ABSTRACT Aspects related to epidemiology of flies belonging to Fannia genus were studied in order to determine predisposing factors for its occurrence in layer hens houses of commercial farms in the state of Minas Gerais, Brazil. An observational, analytical and sectional survey was conducted to verify major epidemiological aspects associated to infestations. This research was accomplished starting from an adapted secondary database of and structured with information on the presence and absence of ectoparasites and arthropods, characteristics of chicken houses, the poultry, type of facilities, geographical location and the management. The study was conducted in four hundred and thirty one houses located in forty three farms visited in 2012 year in the state of Minas Gerais. Ten farms (23.25%) and sixty eight houses (15,77%) were observed the presence diptera belonging to Fannia genus. The specie Fannia admirabilis was found in four farms (9,30%), Fannia albitarsis in two farms (4,65%) and only in one farm (2.32%) was observed the presence of Fannia canicularis. For three farms 6,98% was no possible to identify the species only Fannia genus. The epidemiological aspects for the occurrence of these flies were investigated using Poisson regression models. Characteristics such as farm, city of farm, presence of Histeridae beetles, type of facility (cage, on the floor with or without bedding) and the existence of mechanical removal of manure were associated with the occurrence of Fannia spp.

ABSTRACT Locomotor diseases are still a challenge in modern poultry. Vertebral osteomyelitis (VO) is an emerging disease in broilers worldwide. The inflammatory process in the affected thoracic vertebra (T4) and subsequent spinal cord compression leads to clinical signs related to locomotor impairment, inadequate feeding and drinking, and increased mortality in the affected flocks. The pathogenesis of the disease is poorly understood and Enterococcus cecorum is the bacterium most frequently associated with the disease. However, other bacteria such as E. faecalis, E. durans, Escherichia coli and Staphylococcus aureus have been recently detected in cases of the disease, raising questions regarding its etiopathogenesis. As many questions about VO in broilers remain unanswered, knowledge on its prevention, control and treatment is limited. In this review, we compile and discuss the currently available information concerning VO in broilers and highlight important aspects of the disease.

ABSTRACT This study aimed at determining the clinical and pathological effects of the coinfection of young SPF chickens with chicken anemia virus (CAV) and Mycoplasma gallisepticum (MG) vaccine strains. The clinical signs, gross and microscopic lesions were determined after the experimental coinfection broilers with a CAV genotype 1 vaccine strain given intraperitoneally on the first day of age and a MG F-strain vaccine given intranasally on the 8th day of age. The experimental groups included the negative control (group 1), a group infected with the MG F-strain vaccine (group 2), and a group coinfected with CAV and MG vaccines (group 3). Chicks were examined clinically and post mortem at 23 days of age, and gross and microscopic lesions of the trachea, thymus, and air sacs were compared among treatments (Kruskal-Wallis test). Infections were confirmed by PCR for specific genetic fragments of each agent in the target tissues. Mortality was only observed in chicks on group 3, with two deaths and more severe lesions in the trachea, thymus and air sacs compared with groups 1 and 2 (p< 0.01). Dead chicks presented reduced thymus and spleen size, hemorrhagic trachea with catarrhal exudate and partial obstruction, pericarditis, catarrhal airsacculitis, lungs with liquid and ascites. The surviving chicks in group 3 showed more severe respiratory changes than those in group 2, in addition to thymus and spleen size reduction. Results indicate the adverse effects of the coinfection of young chickens with MG F-strain and CAV genotype 1 vaccines.

ABSTRACT The incidence of the psittacine beak and feather disease virus (BFDV) was investigated in Brazilian native parrots with normal feathering arriving at rescue and triage centers for wild animals (CETAS, IBAMA) in the state of Minas Gerais, Brazil. BFDV DNA was investigated by previously described PCR technique for the partial amplification of BFDV ORF-1 in DNA extracts from blood, cloacal swab or liver of psittacines. Some birds provided more than one sample. Nine species of psittacines were sampled between January 2009 and October 2010. Blood (n=46) or cloacal swab (n=128) samples were obtained from psittacines immediately upon arrival at the triage centers. Liver samples were collected from necropsied birds dead on arrival (n=167). All swab samples were negative, except for one Ara ararauna individual (n=3) which blood presented the BFDV DNA. On the other hand, 11 liver samples were positive for BFDV DNA, with a prevalence of 7.8% in Amazona aestiva (n=140). No BFDV DNA was detected in the liver of Amazona amazonica (n=11), A. vinacea (n=5), A. rhodochorytha (n=4), Anodorhynchus hyacinthinus (n=3), Ara ararauna, (n=3), Aratinga leucophtalma (n=2), Guarouba guarouba (n=1) and Pionus maximiliani (n=1). In most cases, alopecia was not associated with BFDV detection in liver, and liver histopathology was inconclusive. Although all cloacal swab samples were negative, a few psittacines (n=19) that died at CETAS-Belo Horizonte were retested, and 21% were detected as positive in liver. A group of psittacines (n=16) was clinically evaluated, and despite showing feather dystrophy, all birds were negative in the cloacal swabs, except for one, which blood sample was positive (A. ararauna). The obtained sequences of the BFDV strains BH 215 and BH 732 were deposited in the GenBank (JQ649409 and JQ649410). A 98% similarity with strain sequences described in Australia, Japan, and New Zealand was observed. It is possible that these strains arrived in Brazil through the legal and illegal trade of parrots. However, it was not possible to associate BFDV infection with the geographical origin of birds and no local marker was detected. The rates of detection, although similar to other studies, indicate the tendency of a high incidence of the disease, possibly associated with stress, and high bird density and wide transmission in captivity conditions.

Epididymal lithiasis (EL) histopathology is described using light and electronic microscopy in roosters (Gallus gallus domesticus) naturally affected by EL in Minas Gerais, Brazil. The histologic and morphological changes by EL in roosters was performed regarding cellular and subcellular details through light and electron microscopy. Efferent ductules epithelium lysosomal increase in size and numbers, membrane rupture, cellular vacuolation, ciliary loss, basal membrane degeneration, inflammatory reaction with mononuclear infiltrations, edema, epithelial and vascular endothelium losses were described. All industrial and freerange chickens showed EL in varying degrees in the efferent ductules (ED). However, ED altered areas did not correlate with the presence of luminal stones. Non-ciliated ED epithelium cells presented several atypically large lysosomes. Plicae loss and basal vacuoles were observed in the epithelium of dilated regions. Cellular cilia loss and apical cytoplasmic membrane rupture resulted in leakage of the cytoplasmic contents to the ED lumen, and ED epithelium desquamation occurred with or without lesion to the basal membrane. Basal membrane alterations were associated with profound sub-epithelial connective tissue damage. Aggregations of desquamated epithelium and spermatozoa were seen in the lumen of ED and compact aggregates were considered the basis for calculi formation. The widespread occurrence and high severity of EL lesions are indicative of the importance of EL as a cause of infertility in male chickens.

The mortality of passerines native of Southern Minas Gerais, Brazil, in August 2006 and the examination of sentinel free-range chicken eggs in August 2007 in an area surrounding a car battery lead smelter plant is described. The high levels of lead, as detected in the passerines (4.80-12.74 mg/kg) at the onset of mortality and at the follow-up sampling of the free-range chicken eggs (25.02-35.21 mg/kg in shells, 0.41-1.36 mg/kg in yolks and 0.40-0.75 mg/kg in the albumins), used as environmental sentinels, indicated the continuing lead pollution.

Mycoplasma gallisepticum (Mg) infection of wild native Brazilian psittacines (Psittaciformes) which died of any cause during sorting, rehabilitation, or conservation, was investigated by PCR. Two previously described PCR methodologies using Mg specific primers were employed for the analyses of 140 swab samples (cloaca, trachea, or palatine cleft). Average positive Mg detection in cloacal swabs was 51.9%, with 80.0% (n=5) of Blue-and-yellow Macaws (Ara ararauna), 60.0% (n=3) Dusky Parrots (Pionus fuscus), 52.5% (n=59) Amazon Parrots (Amazona aestiva), 50.0% (n=2) Orange-winged Parrots (Amazona amazonica), 50.0% (n=2) Jandaya Parakeetsor Jandaya Conures (Aratinga jandaya), 0% (n=2) Golden Conures or Golden Parakeets (Guarouba guarouba), and 0% (n=2) Hyacinth Macaws (Anodorhynchus hyacinthinus). Palatine cleft swab sampling was more sensitive to detect Mg, with 85.4% (n=17) detection rate, as compared to 67.4% (n=46) obtained with tracheal samples, and 53.5% (n=77) with cloacal swabs. The surprisingly high Mg incidence in psittacines kept in conservation or triage environments is possibly due to the proximity or cohabitation with several bird species during confinement and housing psittacines of different origins together. The implementation of biosecurity measures and species-specific facilities is recommended.

The occurrence of CAV in backyard chickens in the metropolitan area of Belo Horizonte, Brazil, was evaluated. The spleen and thymus of chickens from different origins were collected for DNA extraction and nested-PCR. CAV genome was detected in 30% of the flocks (n=20) examined. CAV origin for backyard chickens is speculated, taking into consideration its widespread incidence in the chicken industry, the contamination of live vaccines with CAV prior to its eradication from SPF flocks, and the use of attenuated CAV vaccines.

A study on the occurrence of epididymal lithiasis (EL) in Gallus gallus domesticus of different breeds and from different geographical regions of Brazil was carried out. Forty breeding roosters were collected in the states Santa Catarina, São Paulo, Minas Gerais, Espírito Santo and Goiás, representing two specific pathogen free Leghorn lines (SPF), one commercial Leghorn layer breeder (Hy-Line) line, two commercial broiler breeder lines (Ross and Cobb), and two backyard chicken flocks. In commercial poultry breeders, EL was observed mainly after 55 weeks of age, and lithus resulted in lower fertility caused by inadequate maturation of spermatozoa and testicular atrophy, which evolved to more severe testicular dysfunction at 100 weeks of age. One hundred percent of the sampled roosters of the evaluated SPF lines presented epididymal lithiasis, which was also observed in all commercial genetic lines. The analysis of EL occurrence revealed no differences among regions and breeds: all regions and genetic lines presented epididymal calculi and the occurrence seemed higher in the more intensively-reared chickens. As for the backyard roosters, 50% presented calculi. Considering the occurrence of EL in the SPF flocks, its primary association with infectious bronchitis virus (IBV) infection was discarded, despite its contribution to fertility loss.

The interference of low or high maternal antibodies titers on the attenuated infectious bursal disease (IBD) virus (IBDV) vaccine infection and its effects on the performance of broilers vaccinated at the 18th day of incubation (in ovo), at one day of age (subcutaneously-SC), or at 15 days of age (drinking water-DW) were investigated. After a series of three live vaccinations, breeders were given or not an IBD oil emulsion vaccine (IBD-OEV) prior to sexual maturity. At day 18 of incubation (in ovo), a commercial vaccine containing HVT and an intermediate IBDV strain or the single HVT vaccine was given. An intermediate IBDV vaccine was given SC at one day of age, or at 15 days of age via DW. The progeny of unvaccinated breeders presented higher neutralizing IBDVspecific antibody (IBDVab) titers at 25 and 40 days of age than those of the progeny of IBD-OEV breeders (p<0.05) at any broilers vaccination age and route. The lower IBDV RNA detection by RT-PCR in the bursa of Fabricius (BF) and the lower IBDV antibody titers in the serum of the groups vaccinated at one and 15 days of age derived from IBD-OEV breeders may indicate antibody-mediated IBDV neutralization. The inovo and one-day vaccinations did not interfere with performance, both in low and high antibody-titered progenies. The in-ovo vaccination against IBD is considered convenient and safe for industrial chickens, irrespective their maternal antibody levels.