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Importantes alterações fisiológicas influenciam o perfil sanguíneo dos ruminantes durante a fase de crescimento, mas poucos estudos abordam os fatores envolvidos nessa dinâmica em cordeiros. O objetivo deste estudo foi caracterizar a dinâmica dos parâmetros hematológicos, da proteína plasmática total (PPT) e do fibrinogênio em cordeiras saudáveis durante os primeiros quatro meses de vida. Foram coletadas amostras de sangue de 35 cordeiras aos 30, 60, 90 e 120 dias de idade para a realização do hemograma. Os parâmetros eritrocitários e leucocitários, a PPT e o fibrinogênio foram determinados. As médias da contagem total de eritrócitos aos 60 e 120 dias diferiram (P < 0,05) da média inicial, apresentando pico de 13,6 x 106 células µL-1 aos 60 dias de idade. Os valores médios do volume globular e da concentração de hemoglobina aumentaram (P < 0,05) até os 90 dias e diminuíram aos 120 dias (36,6% para 33,7% e 11,4 g dL-1 para 10,6 g dL-1 entre 90 e 120 dias, respectivamente). As médias de volume globular médio (VGM) e de concentração de hemoglobina globular média (CHGM) aumentaram (P < 0,05) entre 30 e 120 dias (27,5 µm3 para 29,7 µm3 e 26,6% para 31,4%, respectivamente). A contagem total de leucócitos aumentou (P < 0,05) e atingiu o pico aos 90 dias (9.314 células µL-1). Os picos para contagem de neutrófilos segmentados (5.141 células µL-1) e linfócitos (4.236 células µL-1) ocorreram aos 60 e 90 dias, respectivamente. As médias para a razão neutrófilo: linfócito foram semelhantes (P > 0,05) entre as idades (média de 1,8), porém superiores ao valor de referência para ovinos adultos (0,5). A média inicial do número de eosinófilos (2 células µL-1) foi menor (P < 0,05) que todas as posteriores, e o número de monócitos apresentou o nível mais baixo (P < 0,05) aos 120 dias (232 células µL-1). A média de PPT aos 60 dias (6,4 g dL-1) foi superior (P < 0,05) às demais idades. Com exceção da contagem de neutrófilos bastonetes, basófilos e da concentração de fibrinogênio, os parâmetros hematológicos e a PPT de cordeiras são influenciados pela idade até os quatro meses de vida, e diferem dos intervalos de referência estabelecidos para ovinos adultos. Portanto, a interpretação de hemogramas realizados em cordeiras deve ser feita com base em intervalos de referência específicos para essa faixa etária.

Neighborhood dogs may act as reservoirs and disseminators of vector-borne diseases in urban areas. Accordingly, the aim of this study was to ascertain the health status and the vector-borne pathogens infecting dogs living in public areas with high levels of human movement in the city of Curitiba, southern Brazil. Blood samples from 21 neighborhood dogs that were found in nine of 22 bus stations and two public parks were subjected to a complete blood cell (CBC) count, serum biochemical profiling, a commercial rapid ELISA test and a commercial real-time PCR panel of vector-borne diseases. The CBC count and serum biochemical profiling were within the normal range for dogs and only 1/21 (4.7%) of the dogs was seroreactive for Borrelia burgdorferi sensu stricto. The commercial real-time PCR panel showed that 7/21 (33.3%) of the dogs had Mycoplasma haemocanis infection, 9/21 (42.8%) had ‘Candidatus Mycoplasma haematoparvum’ and 4/21 (19.0%) had both. No statistical association between infected by the agents found here and abnormalities in physical examinations, laboratory tests or ectoparasite presence was found (p > 0.05). In conclusion, neighborhood dogs showed low prevalence of vector-borne diseases and satisfactory wellbeing, and dogs can be used as sentinels for disease exposure.

The objectives of this study were to estimate the phenotypic correlations of residual feed intake (RFI) and gross feed efficiency (GFE) with hematological and metabolic blood profiles of lambs and to determine the differences for these traits in animals of different RFI classes. Twenty Ile de France male lambs, 115±8 days of age and 31.3±4.1 kg of body weight (means ± SD), were individually housed and their dry matter intake was measured over 65 days. They were weighed every 13 days to determine the average daily weight gain and two blood samples were collected at the last two weighings (at 07h30) for analysis of blood variables. The animals were divided into two classes: negative RFI (most efficient: 0.5 SD above the mean; n=8). There were associations among RFI and the serum metabolic variables for albumin (rRFI = 0.74) and creatinine (rRFI = -0.45) and between GFE and serum albumin (rGFE = -0.70). Less efficient animals as measured by RFI had higher serum albumin and lower creatinine levels and showed a tendency to have a greater concentration of total plasma protein. Other serum biochemical parameters were not correlated with GFE and RFI, and no differences between RFI classes were found. There was a correlation between the percentage of eosinophils and RFI (rRFI = -0.65), and such more efficient animals had a higher proportion of these cells and a trend to have a lower percentage of monocytes. This study provided evidence indicating associations between RFI and protein metabolism, as reflected by the serum albumin and creatinine. The hematological findings suggest that RFI is related to susceptibility of lambs to stressand should provide a basis for further research in this regard.

Avaliou-se a influência das estratégias de desmame precoce e de suplementação concentrada no comportamento diário de cordeiros produzidos em pastagem. As estratégias de desmame e de suplementação foram combinadas duas a duas, e resultaram nos seguintes sistemas de produção em pastagem de Tifton-85 (Cynodon spp.): cordeiros mantidos com as mães e não suplementados; cordeiros mantidos com as mães e suplementados com concentrado em creep feeding; cordeiros desmamados precocemente e não suplementados; cordeiros desmamados precocemente e suplementados com concentrado. O delineamento experimental foi em blocos casualizados em esquema fatorial 2x2, com três repetições e cinco cordeiros testes por repetição. Realizaram-se quatro observações de comportamento durante 24 horas, em que foram avaliados os tempos despendidos pelos cordeiros em pastejo, ruminação, amamentação, suplementação e outras atividades. O comportamento e a distribuição das atividades diárias realizadas pelos cordeiros foram influenciados pelas estratégias avaliadas. A presença do leite ou do suplemento concentrado na dieta são importantes moduladores da atividade de pastejo, e a ausência destas fontes de nutrientes é compensada pelo aumento no tempo de pastejo. Essa resposta reflete a diminuição do aporte nutricional e a menor eficiência na colheita da forragem pelos cordeiros. O aumento no tempo de pastejo determina maior dispêndio energético, que associado à menor eficiência de colheita e ao baixo aproveitamento da forragem ingerida tem impacto negativo no desempenho de cordeiros mantidos exclusivamente em pastagem.The objective in this work was to evaluate the influence of early weaning and concentrate supplementation strategies on the daily behavior of grazing lambs. Both strategies of weaning and supplementation were combined in pairs, resulting in four production systems on Tifton-85 (Cynodon spp.) pasture: suckling lambs not supplemented; suckling lambs supplemented with concentrate in creep feeders; early weaned lambs not supplemented; early weaned lambs supplemented with concentrate. The experimental design was randomized blocks in 2x2 factorial arrangement with three replications and five lambs per replication. Four observations of behavior were performed during 24 hours, evaluating the time spent by lambs on grazing, rumination, suckling, supplementation and other activities. The behavior and distribution of daily activities performed by the lambs were influenced by the both strategies evaluated. Suckling and concentrate supplementation are important modulators of grazing activity and the absence of these nutrient sources is compensated by an increase in grazing time. This reflects the decrease in nutrient intake and the lower efficiency in harvesting forage by lambs. The increase in grazing time requires greater energy expenditure, which associated with lower harvest efficiency and low utilization of forage intake has negative impact on the performance of lambs produced exclusively on pasture.

Abstract Neighborhood dogs may act as reservoirs for several zoonotic protozoan infections, particularly in urban areas, thus constituting a potential public health threat. Accordingly, the aim of the present study was to evaluate the exposure of neighborhood dogs to four protozoan pathogens in public areas with high levels of human movement in Curitiba, southern Brazil. Blood samples from 26 neighborhood dogs were screened by means of the indirect immunofluorescent antibody test (IFAT) for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum, and a questionnaire was answered by the respective keeper. A total of 8/26 dogs (30.7%) seroreactive to T. gondii, 3/26 (11.5%) to N. caninum and 2/26 (7.7%) to both were identified. All the samples were seronegative for T. cruzi and Leishmania spp. Pathogen seroreactivity was not associated with the daily human movements or other epidemiological variables investigated (p > 0.05). In conclusion, the low seroprevalence for T. gondii and N. caninum indicated low environmental and food risk for animal infection and the seronegativity for Leishmania spp. and T. cruzi may reflect the absence of these pathogens in urban areas of Curitiba. Moreover, neighborhood dogs may be used as environmental sentinels for the presence of protozoan pathogens and their vectors.