BIOPSIA RETAL EM OVINOS E CAPRINOS PARA MONITORAMENTO E DIAGNÓSTICO ANTE MORTEM DE SCRAPIE: NÚMERO DE FOLÍCULOS LINFOIDES EM DUAS COLHEITAS CONSECUTIVAS

Este estudo teve por objetivo avaliar a quantidade de tecido linfoide associado à mucosa retal obtido pela técnica de biopsia retal e a possibilidade de se realizarem duas biopsias consecutivas, em diferentes intervalos de tempo, para monitoramento e diagnóstico ante mortem de scrapie. Para isso, foram estudados 56 ovinos e 32 caprinos. No dia zero, todos os animais foram submetidos a biopsias e, posteriormente, divididos em grupos. As colheitas foram realizadas aos dias sete, 14, 21 e 28 para os ovinos, e 14, 21 e 28 para os caprinos. De 176 amostras, 151 (85,8%) foram colhidas da mucosa retal e, em 25 (14,2%), houve falha de colheita. Considerando-se as amostras colhidas da mucosa retal (151), em 56,86% das amostras de ovinos e 51,61% de caprinos, no dia 0, havia ?3 folículos linfoides (FL). Na segunda colheita, 58,97% das amostras de ovinos possuíam ?3 FL e, para caprinos, 33,33%. Na comparação do número de FL entre a primeira e a segunda colheitas houve diferença (p<0,05) entre os dias 0 e 7 (com mais FL no dia 0) e 0 e 28 (com mais FL no dia 28) para ovinos, e entre os dias 0 e 28 (com mais FL no dia 0) para caprinos. Comparando-se as duas espécies, não houve diferença no número de FL nos dias 0, 14 e 21. No dia 28, a proporção de amostras com ?3 FL foi maior nos ovinos (p<0,05) que nos caprinos. Concluiu-se que a técnica de biopsia retal compreende método útil para a obtenção de tecido linfoide associado à mucosa para avaliação imuno-histoquímica voltada ao monitoramento e diagnóstico ante mortem de scrapie em ovinos e caprinos. Porém, a colheita inadequada e a obtenção de número insuficiente de FL podem ocasionar a necessidade de repetição da técnica, o que pode ser realizado após 14 dias da primeira colheita, sem redução no número de FL. Palavras-chave: doença priônica; encefalopatias espongiformes transmissíveis; imuno-histoquímica; pequenos ruminantes; tecido linfoide associado a mucosa retoanal

Assessment of a hands-on method for FAMACHA© system training

The FAMACHA©system is a method for selective anthelmintic treatment comprising earlydetection of haemonchosis in sheep and goats. In order to evaluate the hands-on trainingmethodology and the learning level of the participants, we analyzed data from 30 trainingevents involving 47 training classes conducted in the State of Paraná, Brazil, from July/2009to May/2011, during which period a total of 1004 participants did 20,080 FAMACHA©clas-sifications. In the practical training sessions, each participant individually evaluated 20animals with known haematocrit values. Every participant per training event was given aunique number, whereupon each of the animals in a given event was FAMACHA©classifiedby all the trainees involved, in the same trainee number sequence. After each consecutiveanimal had been evaluated by every one of the participants, its haematocrit and corre-sponding FAMACHA©category were announced before the next animal was presented. Thenumber of persons in training, which ranged from 5 to 39 per session, did not significantlyaffect the average error of the groups of participants involved (p > 0.05). The average errorin the classification of the first animal on a scale with a perfect score of zero was 2.5, signif-icantly greater than the error of 0.56 of the twentieth one (p 0.05). Similarly, the average errors in FAMACHA©classification were not significantlyinfluenced by the occupation or gender of the participants, nor whether there were ani-mals in all five FAMACHA©categories or only in categories 1, 2, 3 and 4 per training event(p > 0.05).Fundação Araucária (Araucaria Foundation), Programa Universidade Sem Fronteiras ("University Without Borders Program").http://www.elsevier.com/locate/vetparhb201

Sensitivity and specificity of the FAMACHA© system in Suffolk sheep and crossbred Boer goats

Sheep and goats are the species of farm animal with the highest growth rate in Paraná State. The main problems facing Paraná State flocks are gastrointestinal parasites and anthelmintic resistance. One of the newest resources used to slow down the development of anthelmintic resistance is the FAMACHA(©) system, a selective method useful for controlling gastrointestinal verminosis in small ruminants. The purpose of the present research was to evaluate the sensitivity and specificity of the FAMACHA(©) system in sheep and goats and to compare the results for both species. The conjunctivae of 83 Suffolk ewes and 60 adult crossbred Boer does were evaluated by the same trained person using the FAMACHA(©) system. The packed cell value (PCV) served as the gold standard for clinical FAMACHA(©) evaluation. To calculate the sensitivity and specificity of the FAMACHA(©) system, different criteria were adopted in turn: animals classified as FAMACHA(©) (F(©)) 4 and 5, or 3, 4 and 5, were considered to be anemic (positive test), and animals classified as F(©)1, 2 and 3, or 1 and 2 were considered to be non-anemic (negative test). Three standard values of PCV, namely ≤19%, ≤18% or ≤15%, were used to confirm anemia. At all cut-off levels, the sensitivity increased if F(©)3 animals were included as being anemic. However, changes in levels of sensitivity were associated with reciprocal changes in specificity. The sensitivity was higher for sheep than for goats, excepting when the criteria included PCV≤18 and F(©)3, F(©)4 and F(©)5 were considered positive. In contrast, the specificity was always lower in sheep for any criteria adopted. Other than in goats, using the ≤15 cut-off level for sheep, it is possible to opt not to drench the animals that were shown to be F(©)3 because the sensitivity is still high, indicating that few animals that should have been drenched were overlooked. In goats, in contrast, the low sensitivity at all cut-off levels made it too risky to leave F(©)3 animals undrenched. Even though the number of correct treatments for goats was always higher than that for sheep, the opposite was true for the kappa index for all the criteria tested. Therefore, the FAMACHA(©) system is suitable for the identification of anemic animals of both species. It is necessary that all small ruminants classified as FAMACHA(©) level 3 are also treated to increase the sensitivity of the method.http://www.elsevier.com/locate/vetparhb2016Veterinary Tropical Disease

Effects of protein supplementation on resistance and resilience of lambs naturally infected with gastrointestinal parasites

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, 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

RECTAL BIOPSY IN SHEEP AND GOATS FOR MONITORING AND ANTE-MORTEM DIAGNOSIS OF SCRAPIE: NUMBER OF LYMPHOID FOLLICLES IN TWO CONSECUTIVE COLLECTIONS

This study aimed to evaluate the amount of lymphoid tissue associated with the rectal mucosa obtained by rectal biopsy and the possibility of two consecutive biopsies at different time intervals, for monitoring and ante-mortem diagnosis of scrapie. Rectal mucosa samples were collected from 56 sheep and 32 goats in two steps. In the first step, on day 0, all animals were tested and, for the second step, the animals were divided into groups and each group was subjected to collection on different dates: for sheep 7, 14, 21, and 28 days after the first one and, for goats, on days 14, 21, and 28. From 176 samples, 151 (85.8%) were collected from the rectal mucosa, and in 25 (14.2%) there was a collection failure. Considering the rectal mucosa samples (151), 56.86% of the sheep samples and 51.61% of the goat samples, on day 0, had more then ≥3 lymphoid follicles (LF). In the second collection, 58.97% of the sheep samples showed ≥ 3 LF and 33.33% of the goat samples. Comparing the number of LF of the same animals between the first and second collections, there was a significant difference (p <0.05) between days 0 and 7 for sheep (with more FL on day 0) and days 0 and 28 (with more LF on day 28) and days 0 and 28 for goats (with more FL on day 0). There was no significant difference in the number of FL assessed on dates 0, 14, and 21 when comparing the different species, sheep and goats. On day 28, sheep samples showed a higher number (p <0.05) of LF than goats. It was concluded that rectal biopsy technique involves useful method for obtaining lymphoid tissue associate to mucosa for immunohistochemistry assessment to monitoring and ante-mortem diagnosis of scrapie in sheep and goats. However, inappropriate sampling or insufficient numbers of FL can generate the necessity to repeat the technique, which could be done 14 days after the first collection, without reduction in the number of the FL. Keywords: immunohistochemistry; prionic disease; recto-anal mucosa associated lymphoid tissue; small ruminants; transmissible spongiform encephalopathies. Enviado em: 14 julho de 2013 Aceito em: 20 abril de 2016 Introdução Encefalopatias espongiformes transmissíveis (ETTs) ou doenças priônicas são desordens neurológicas, progressivas e fatais que afetam animais e humanos. Associam-se ao acúmulo de proteína priônica alterada no sistema nervoso central (SNC) e as lesões histológicas compreendem principalmente vacuolização e morte neural(1). São muitas as enfermidades que compõem o grupo das ETTs, incluindo encefalopatia espongiforme bovina (EEB) em bovinos, scrapie em pequenos ruminantes e a doença de Creutzfeldt-Jakob (DCJ) em humanos(2). Segundo Detwiler e Baylis(3), a scrapie tem sido relatada em diversos países do mundo e está presente em muitas regiões produtoras de ovinos. É endêmica em vários países da Europa, Canadá e Estados Unidos, porém Austrália e Nova Zelândia são consideradas livres da doença(3,4). À semelhança do que ocorre nas demais EETs, na scrapie há acúmulo da isoforma anormal (PrPSc) da proteína priônica celular (PrPC) não apenas no SNC, mas também no sistema linforreticular (SLR) e, variavelmente, em outros tecidos e fluidos corporais(1). O acúmulo da PrPSc em tecidos linfoides levou ao desenvolvimento de procedimentos de biopsia para o diagnóstico ante mortem da scrapie em ovinos, utilizando tecidos acessíveis como a tonsila(5) e terceira pálpebra(6), e a técnica de imuno-histoquímica (IHQ). Por outro lado, a grande área de folículos linfoides presente no reto de ovinos(7) tornou a biopsia retal uma possibilidade de diagnóstico ante mortem da scrapie. Amostras da mucosa retal têm sido colhidas e analisadas por meio de provas de IHQ para avaliar a presença de PrPSc no tecido linfoide associado à mucosa retoanal (RAMALT, do inglês Recto-Anal Mucosa Associated Lymphoid Tissue)(8,9). No Brasil, o primeiro relato de scrapie foi em 1978, em um ovino Hampshire Down, importado da Inglaterra(10). Segundo a OIE, de 2008 a 2014 foram sacrificados 41 animais no país, em surtos de scrapie(11). Desde 2008, o diagnóstico de scrapie é realizado por meio da técnica de IHQ a partir de amostras do SNC e tecidos linfoides(12). Porém, no caso de tecidos linfoides associados à mucosa retal, pode haver necessidade de novas colheitas em curtos intervalos de tempo devido à escassez de tecido para o diagnóstico da doença que, segundo Leal et al.(13), deve ser de no mínimo três folículos linfoides (FL) por amostra. Visando ao reconhecimento de boas técnicas para o monitoramento e o diagnóstico ante mortem da scrapie, o presente estudo teve por objetivo avaliar a quantidade de tecido linfoide associado à mucosa retal obtido pela técnica de biopsia retal e com vistas à avaliação imuno-histoquímica, bem como a possibilidade de se realizarem dois procedimentos de biopsia consecutivos, em diferentes intervalos de tempo, em ovinos e caprinos