To determine the polymorphisms of the prion protein gene in sheep from the state of Paraná, Brazil, 323 animals of meat breeds (Suffolk, Hampshire Down, Texel, Ile de France, Dorper, Dorset, Santa Inês and crossbreds) were genotyped by restriction fragment length polymorphism (RFLP) analysis. The most frequent allele was ARQ, with a frequency of 0.61, followed by ARR (0.30). VRQ and AHQ alleles were present at very low frequencies (0.13 and 0.05 respectively), and the ARH allele was not found. Seven genotypes were identified (ARR/ARR, ARR/ARQ, ARQ/ARQ, ARR/VRQ, ARR/AHQ, ARQ/VRQ and ARQ/AHQ), of which ARQ/ARQ was the most frequent (0.41). The Santa Inês breed and crossbred animals showed the highest genotypic variability.

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The fecal egg count reduction test (FECRT)

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...