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The main pathogenic treponemes causing bovine digital dermatitis were identified from 17 infected herds in southern Brazil for the first time in this study using PCR. We did not find a relationship between treponeme phylogroup composition and clinical classification. Treponema phagedenis was present in all lesions. Rumen fluid was implicated as a reservoir location for these pathogens.A lthough bovine digital dermatitis (BDD) has been known to occur in Brazil since the early 1990s (1), there have been no attempts to describe the possible pathogens involved, apart from reports of histopathological (2) and electron microscopic (3) findings. Treponema species are difficult to culture, so molecular approaches are useful for detecting and identifying these spirochetes (4, 5). The present study describes, for the first time, the frequencies of the major treponeme species in BDD lesions in Brazil. Similar results in Europe, North America, and Asia (6-11) confirm the polytreponemal aspect of this clinical condition.Farms in southern Brazil where BDD infections are endemic (n ϭ 28) were identified by consulting veterinary records. Previously identified dairy cows (n ϭ 200) were individually reexamined and, if positive for BDD (n ϭ 22), were photographed and their lesions classified according to clinical stage, from M1 to M4 (12-14). Samples (n ϭ 22) were surgically excised, placed in phosphatebuffered saline (PBS) solution, and refrigerated (4°C to 8°C) until processing. The infected digit was then topically treated with antibiotics (oxytetracycline) and bandaged. Using a stomach tube, ruminal fluid (Ն50 ml of fresh fluid) was collected from 15 cows from seven different BDD-positive herds, which were chosen by convenience. From one BDD-free herd with a history of lameness but without any clinical BDD lesions detected on previous examinations of the whole herd, ruminal fluid from 10 cows was sampled for use as a negative control. All samples underwent extraction of bacterial DNA, as previously described (12,15). A nested-PCR method was used, as previously described (10). The treponeme-specific primers were called Treponema sp., Treponema medium/T. vincentii-like, Treponema phagedenis-like, and Treponema denticola/T. putidum-like (10). The research was approved by the Committee for the Ethical Use of Animals of Pontifícia Universidade Católica do Paraná (PUCPR) (registration no. 646) in 2011.Of the herds, 17 (60.71%) had BDD lesions on the day of examination and were positive for subsequent molecular BDD detection. The lesions were in different clinical stages (14) and were classified as follows: 13.64% were M1, 45.45% were M2, 22.73% were M3, and 18.18% were M4. However, certain lesions classified as M2 or M3 contained areas that were M4 or M1. In comparison, the cows in the present study exhibited considerably more M2 lesions (45.45% versus 21.03% in the previous study) and fewer M4 lesions (18.18% versus 50.03% in the previous study) ( Table 1). The reason for this observation or why the different forms can transition f...

For the last several decades, antimicrobial compounds have been used as feed additives to promote piglet growth at weaning, through the prevention of subclinical and clinical disease. However, few studies have assessed the influence of these antibiotics on the immune response of nursery pigs, as well as the relation between performance, health, and immunity of animals that receive feed additives. Therefore, the present study aimed to evaluate the effects of colistin and tylosin when used as feed additives on the performance, incidence of diarrhea, and immune response of nursery pigs. In this study, 72 weaned pigs (average age, 28 days) were allotted into one of three treatment groups: a control group (feed with no antibiotics), tylosin group (feed containing 22 ppm tylosin), and colistin group (feed containing 20 ppm colistin). Weekly, during a five week period, the average daily feed intake, average daily gain, and feed conversion ratio of the pigs were evaluated. Stools were scored daily, in accordance with a fecal texture scale. Blood samples were collected on the day of housing (d0) and on d7, d21, d28, and d35 for immune cell phenotyping. The results of this study showed that piglets in both the colistin and tylosin groups exhibited a significantly higher average daily feed intake, resulting in a higher body weight at the end of the experimental period (d35) when compared with piglets from the control group. Colistin and tylosin also significantly reduced the incidence of diarrhea. Colistin and tylosin modulated the piglets' immune responses, particularly on d28, by changing the percentage of circulating B lymphocytes, CD4 + CD8 + T cells, and the CD4:CD8 ratio. ResumoNas últimas décadas, os compostos antimicrobianos têm sido utilizados como aditivos alimentares para promover o crescimento de leitões ao desmame, por meio da prevenção de doenças clínicas e subclínicas. No entanto, poucos estudos avaliaram a influência destes antibióticos sobre a resposta imune de leitões na fase de creche, bem como a relação entre o desempenho, a saúde e a imunidade dos animais com o uso destes aditivos. Sendo assim, o presente estudo teve como objetivo avaliar o efeito da colistina e da tilosina como aditivos na alimentação sobre o desempenho, incidência de diarreia e resposta imune de leitões na fase de creche. Para isso, foram utilizados 72 suínos recém-desmamados, com 28 dias de idade em media, divididos em três tratamentos: grupo controle (ração sem antibiótico), grupo tilosina (ração com 22 ppm de tilosina), grupo colistina (ração com 20 ppm de colistina). Semanalmente, durante cinco semanas, foi analisado o consumo deração diário, o ganho de peso diário e a conversão alimentar dos leitões. As fezes foram avaliadas diariamente, com a atribuição de escores relacionados à sua consistência. Amostras de sangue foram coletadas no momento do alojamento (d0) e aos d7, d21, d28 e d35, sendo submetidas à técnica de citometria de fluxo. Os resultados demonstraram que tanto o grupo colistina como o grupo tilosina promove...

In this study, the objective was to evaluate the efficacy of protein supplementation on gastrointestinal nematode control in lambs naturally infected. Sixty weaned Ile de France and Texel crossbred lambs, with 60 days of age, were divided into three groups (n=20) according to the level of protein in the concentrate: low protein (LP; 8.5%), moderate protein (MP; 15%), and high protein (HP; 25%). The daily amount of concentrate offered was based on 3% of live weight, which was continued throughout the experiment of 98 days. Evaluations were conducted biweekly from days 0 (D0) to 98 (D98). There were no significant differences (p > 0.05) in the average weight among the LP, MP and HP groups, which was 22.0, 21.4, and 21.1 kg, respectively, on D0 and 46.4, 48.3, and 48.2 kg, respectively, on D98. The daily weight gain was not significantly different among the groups (LP, 250 g; MP and HP, 276 g; p > 0.05). The average egg count per gram of feces (epg) of the LP group on D98 (6,765; an increase of 5,690 epg from D0) was higher than that of the MP and HP groups (1,617.5, p < 0.05 and 3,435, p > 0.05, respectively), which remained constant throughout the study. The hematocrit values decreased (p < 0.05) from D0 to D98 only in the LP group. Only in the HP group (p < 0.05), the mean serum total protein concentration increased from D0 (5.3 g dL-1) to D98 (5.8 g dL-1). The average albumin level on D98 (2.10 g dL-1) was lower than that on D0 (2.52 g dL-1) in the LP group (p < 0.05). During the study, 10 lambs overall were treated with anthelmintic because the epg values exceeded 10,000; six treated lambs were from the LP group, 3 from the HP group, and only 1 from the MP group. These results indicate that supplementation of diet with 15% protein increases the resistance and resilience of lambs to gastrointestinal parasites.

RESUMO: O presente trabalho descreveu características e comparou mensurações do fígado, vesícula biliar, rins, vesícula urinária e jejuno de coelhos da raça Nova Zelândia Branco (NZB) jovens e adultos. O grupo dos jovens foi composto por 39 coelhos de ambos os sexos (20 machos e 19 fêmeas), desmamados aos 30-31 dias de idade, sendo as avaliações realizadas aos 35, 56 e 77 dias de idade. O grupo dos adultos foi composto por 23 fêmeas e 15 machos, com idade superior a 6 meses, sendo realizada uma avaliação ultrassonográfica por animal. O exame consistiu na avaliação do fígado, vesícula biliar, rins direito e esquerdo, jejuno e vesícula urinária. Todos os animais foram pesados antes dos exames. O peso médio dos animais aumentou (p<0,05) dos 35 dias até a idade adulta. Tanto nos adultos quanto nos jovens, o fígado apresentou-se predominantemente isoecogênico ao rim direito e com textura homogênea. A vesícula biliar apresentou-se em formato ovoide alongado, variando de piriforme à amendoado, com conteúdo anecogênico, não sendo visível em 2,6% dos coelhos jovens e em 26,3% dos adultos. O comprimento e a largura da vesícula biliar nas idades de 35, 56, 77 dias e adultos foram: 1,06 e 0,39; 1,44 e 0,53; 1,41 e 0,58; 1,57 e 0,67cm, respectivamente. Considerando jovens e adultos, as mensurações da vesícula biliar e dos rins esquerdo e direito apresentaram correlação positiva (p<0,05) com o peso. Os rins apresentaram-se no formato de elipse e com superfície regular, com aumento (p<0,05) dos 35 dias à idade adulta. Houve correlação positiva (p<0,05) entre os volumes renais direito e esquerdo. A descrição da vesícula urinária mais encontrada (86%) foi a com conteúdo anecogênico, com pequenas estruturas ecogênicas livres no lúmen, tanto em jovens quanto em adultos. Não houve diferença (p>0,05) da espessura das camadas do jejuno entre as idades, apresentando média de 0,23 cm para todos os animais. Estes são os primeiros dados brasileiros de características ultrassonográficas de fígado, vesícula biliar, rins, jejuno e vesícula urinária para coelhos NZB de 35, 56 e 77 dias de vida e adultos.