Francisco Ernesto Moreno Bernal

Skin and coat traits in sheep in Brazil and their relation with heat tolerance.

The objective of this study was to evaluate and compare physical parameters in groups of sheep with different phenotypic characteristics in the Centre-west region of Brazil. Five groups of sheep, with nine animals per group, were selected, three groups of Santa Inês animals with different coat colours (white, brown and black), one group with crossbred animals (Santa Inês × Bergamasca) and one group with animals of the Bergamasca breed. The following traits were evaluated: coat thickness, number and length of hair, pigmentation level in the coat and the skin as well as the percentage area of sweats glands in the skin tissue, carried out by histological analysis. The number of hairs and the area of sweats glands were not significantly different between the evaluated groups. The Bergamasca breed showed low pigmentation of the skin and long hairs. The levels of pigmentation of the hair and of the skin were highly correlated. Between the Santa Inês groups, the group with white hair showed the better parameters for heat adaptation, while the brown hair group showed the lower heat adaptation when compared with another hair breed groups.

Trypanosoma cruzi in the Chicken Model: Chagas-Like Heart Disease in the Absence of Parasitism

Background The administration of anti-trypanosome nitroderivatives curtails Trypanosoma cruzi infection in Chagas disease patients, but does not prevent destructive lesions in the heart. This observation suggests that an effective treatment for the disease requires understanding its pathogenesis. Methodology/Principal Findings To understand the origin of clinical manifestations of the heart disease we used a chicken model system in which infection can be initiated in the egg, but parasite persistence is precluded. T. cruzi inoculation into the air chamber of embryonated chicken eggs generated chicks that retained only the parasite mitochondrial kinetoplast DNA minicircle in their genome after eight days of gestation. Crossbreeding showed that minicircles were transferred vertically via the germ line to chicken progeny. Minicircle integration in coding regions was shown by targeted-primer thermal asymmetric interlaced PCR, and detected by direct genomic analysis. The kDNA-mutated chickens died with arrhythmias, shortness of breath, cyanosis and heart failure. These chickens with cardiomyopathy had rupture of the dystrophin and other genes that regulate cell growth and differentiation. Tissue pathology revealed inflammatory dilated cardiomegaly whereby immune system mononuclear cells lyse parasite-free target heart fibers. The heart cell destruction implicated a thymus-dependent, autoimmune; self-tissue rejection carried out by CD45+, CD8γδ+, and CD8α lymphocytes. Conclusions/Significance These results suggest that genetic alterations resulting from kDNA integration in the host genome lead to autoimmune-mediated destruction of heart tissue in the absence of T. cruzi parasites.

Number of flocks on the same litter and carcase condemnations due to cellulitis, arthritis and contact foot-pad dermatitis in broilers.

1. This study was conducted to verify the impact of different kinds of material and the number of times of litter reuse on the incidence of chicken pathologies. Approximately 4·5 million broilers from conventional Brazilian farms were evaluated in the abattoir for cellulitis, arthritis and contact foot-pad dermatitis. 2. Four different kinds of litter material, Brachiaria grass, corncob, sawdust and rice shell, were used. Brachiaria grass litter showed the highest incidence of contact foot-pad dermatitis. Corncob litter also showed some negative effects on foot quality. Broilers raised on rice shell litter showed good results in terms of the incidence of contact foot-pad dermatitis. The best results were obtained with sawdust litter, because the incidence of cellulitis and arthritis were the lowest and the incidence of contact foot-pad dermatitis was also very low.

Parasite Induced Genetically Driven Autoimmune Chagas Heart Disease in the Chicken Model

The Trypanosoma cruzi acute infections acquired in infancy and childhood seem asymptomatic, but approximately one third of the chronically infected cases show Chagas disease up to three decades or later. Autoimmunity and parasite persistence are competing theories to explain the pathogenesis of Chagas disease 1, 2. To separate roles played by parasite persistence and autoimmunity in Chagas disease we inoculate the T. cruzi in the air chamber of fertilized eggs. The mature chicken immune system is a tight biological barrier against T. cruzi and the infection is eradicated upon development of its immune system by the end of the first week of growth 3. The chicks are parasite-free at hatching, but they retain integrated parasite mitochondrial kinetoplast DNA (kDNA) minicircle within their genome that are transferred to their progeny. Documentation of the kDNA minicircle integration in the chicken genome was obtained by a targeted prime TAIL-PCR, Southern hybridizations, cloning, and sequencing 3, 4. The kDNA minicircle integrations rupture open reading frames for transcription and immune system factors, phosphatase (GTPase), adenylate cyclase and phosphorylases (PKC, NF-Kappa B activator, PI-3K) associated with cell physiology, growth, and differentiation 3, 5-7, and other gene functions. Severe myocarditis due to rejection of target heart fibers by effectors cytotoxic lymphocytes is seen in the kDNA mutated chickens, showing an inflammatory cardiomyopathy similar to that seen in human Chagas disease. Notably, heart failure and skeletal muscle weakness are present in adult chickens with kDNA rupture of the dystrophin gene in chromosome 1 8. Similar genotipic alterations are associated with tissue destruction carried out by effectors CD45+, CD8γδ+, CD8α lymphocytes. Thus this protozoan infection can induce genetically driven autoimmune disease.

Doságem de cortisol sánguíneo em suínos submetidos áo mánejo pré-ábáte e insensibilizáção elétricá

SUMMARY The dosage of cortisol concentration has beenused as stress measure parameter of swinebreedings. Serum cortisol concentration wasdetermined in finishing pigs in rest (group 1) andin finishing pigs submmited to pre-slaughter han-dling and electric sttuning (group 2). Blood fromslaughtered swine were collected immediatelyafter sttuning. Cortisol concetration average forgroup 1 animal was of 21.70 ng/ml while for thegroup 2 was of 74.5 ng/ml, the difference betweencortisol levels were significant (p<0.001)suggesting stressfull condition of pre-slaughterhandilng and electric sttunig for those studied. ThepH average of carcasses from the animalsslaughtered after 24 h in the cold chamber was 6.2and in their visual evaluation, carcasses withcharacteristics PSE (pale, soft and exsudative) orDFD (dry, firm and dark) were not detected. INTRODUCAOA implementacao de nova tecnologianos sistemas de criacao, o melhoramentogenetico do rebanho, o controle sanitario,vem consolidando o consumo da carnesuina seja industrializada, ou

Absence of VanA- and VanB-Containing Enterococci in Poultry Raised on Nonintensive Production Farms in Brazil

ABSTRACT We examined cloacal samples from poultry raised on nonintensive production farms in Brazil for the presence of vancomycin-resistant enterococci. No VanA- or VanB-containing enterococci were identified in a total of 200 cloacal swabs. The most prevalent species were Enterococcus gallinarum (vanC1; 13.0%) and E. casseliflavus (vanC2/3; 5.5%).

Influence of stocking density on growth performance and welfare of juvenile tilapia ( Oreochromis niloticus ) in cages

A intensificacao da producao de tilapias pode gerar implicacoes negativas sobre o desempenho e o bem-estar dos peixes. Assim, e essencial determinar a densidade correta para otimizar a producao. O objetivo deste estudo foi avaliar o desempenho e o bem-estar de tilapias-do-nilo (Oreochromis niloticus) juvenis, com peso inicial medio de 30g (± 2,70), criadas em tres diferentes densidades de estocagem, em gaiolas de flutuacao. Os peixes foram alimentados tres vezes/dia, com racao contendo 32% de proteina bruta, durante 74 dias. O desenho experimental foi completamente ao acaso, com tres tratamentos (250 peixes/m3, 350 peixes/m3 e 450 peixes/m3) e quatro replicas. Os parâmetros fisico-quimicos da agua foram monitorados durante o experimento. A elevacao da densidade de criacao causou reducao no peso final dos peixes, no ganho de peso, no ganho de peso diario, no comprimento padrao e na taxa de sobrevivencia, bem como elevou a taxa de conversao alimentar. Entretanto, densidades mais elevadas reduziram o efeito na variacao de peso. Nao houve influencia da densidade de criacao nos parâmetros de biomassa final, da concentracao de glicose sanguinea e de cortisol serico. Portanto, o aumento na densidade de criacao compromete o desenvolvimento e a taxa de sobrevivencia dos peixes, mas nao influencia os parâmetros fisiologicos de estresse. Assim, o tratamento com 250 peixes/m3 apresentou resultados mais apropriados ao melhor desempenho dos peixes.

Hemato-biochemical profile of meat cattle submitted to different types of pre-loading handling and transport times

Abstract Pre-loading handling and conditions of transport are related to welfare, disease risk and product quality of production animals. These steps continue to be one of the major animal management problems in Brazil. This study evaluated the effects of different types of pre-loading handling and road transport times on the haematological and biochemical traits of cattle. Eighteen male cattle were submitted to three travel times (24, 48 and 72 h) in a truck soon after load using different types of pre-loading handling: traditional (rough handling), training (gentle handling) and use of flags to movement cattle. Haematological traits, blood biochemical measures as well as blood and faecal cortisol were analysed in order to assess animal welfare and physiological status. The traditional management showed to be more stressful, also had animals with a greater number of neutrophils and lower numbers of lymphocytes than handling with flags, showing that animals submitted to more stressful situations can have compromised immune system. Serum aspartate aminotransferase concentrations were within the reference levels and when taken together with increased creatine kinase patterns observed indicate muscle damage in traditional management. Decrease in glucose concentrations over time from traditional management to flag management was observed, while fructosamine was increased in traditional management with 72 h of travel. When taken together, all reported factors, immune, enzymatic, energetic and hormonal, indicate that the quality of pre-loading handling and time of transport were determinant for animal welfare, its homeostatic balance and sanitary conditions.