Avaliação de alterações intestinais macroscópicas e correlação com aspetos microbiológicos em Perdiz-vermelha (Alectoris rufa)
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2018-07-23
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Atualmente, mais de 30 milhões de perdizes-vermelhas são produzidas na Europa e, só nos EUA, este tipo de avicultura representa um impacto de 5.000 milhões de dólares. A produção destas aves é feita sobre um sistema semi-intensivo e o principal desafio são os problemas intestinais, que representam cerca de 84% das prescrições de antibióticos. As doenças intestinais principais são provocadas por coccídeas e protozoários flagelados. Embora haja um vasto conhecimento destes parasitas, permanecem por descobrir muitos aspetos relativos à epidemiologia e controlo. Assim, a melhor compreensão dos fenómenos que interligam a microbiologia, parasitologia, patofisiologia e zootecnia é fundamental para o desenvolvimento de estratégias de promoção da saúde intestinal. Neste estudo, executou-se um protocolo que integrou as 4 temáticas anteriormente descritas através do acompanhamento de 2 explorações de 2080 e 4400 perdizes, no centro de França. Semanalmente procedeu-se à medição da temperatura e pH da água de bebida, levantamento da informação relativa ao comportamento das aves, alterações de maneio, tratamentos e escolha aleatória de 5 animais para análises laboratoriais. A nível laboratorial, em cada um dos 3 segmentos intestinais (duodeno, jejuno/íleo e ceco), determinou-se a carga parasitária, procedeu-se à monitorização das populações bacterianas de Escherichia coli, Enterococcus spp., Campylobacter spp. e fungos tendose fotografado para posterior análise e avaliação de lesões e alterações intestinais. Ainda se executaram esfregaços e colorações do trato digestivo com o objetivo de compreender e avaliar a sua utilização em ambiente prático. Os resultados deste estudo revelaram que a monitorização da temperatura e pH da água é importante, sendo que temperaturas mais frescas (iguais ou inferiores a 24 ºC) e valores de pH ácidos (entre 3 e 4) pareceram preferíveis. Alguns parâmetros de maneio como a idade de saída para o parque de voo, condição corporal e utilização de tratamentos parecem ser bons indicadores de qualidade de bandos. No que concerne às parasitoses, confirmou-se que a epidemiologia e controlo das mesmas permanecem mal compreendidos, uma vez que tanto os tratamentos como os quadros clínicos não corroboraram com o descrito. Observaram-se tratamentos sem eficácia e, ao mesmo tempo, animais com sinais intestinais evidentes de coccidiose sem se refletir no comportamento, condição corporal e mortalidade. Os tratamentos antibióticos parecem influenciar positivamente a existência de fungos em todos os segmentos intestinais e o acesso ao exterior parece determinar a presença e carga de Campylobacter spp. em todo o intestino. A monitorização de populações Gram-negativas e Gram-positivas através da coloração de esfregaços de conteúdo intestinal revelou-se ineficaz, verificando-se heterogeneidade e dificuldade na observação das lâminas. Apesar disso, esta coloração verificou-se útil na identificação de bactérias com morfologias atípicas, como do género Sarcina e espirais/encurvadas, que parecem desenvolver-se aquando de alterações gastrointestinais agressivas. O uso da coloração May-Grunwald-Giemsa e HemacolorÒ demonstrou-se eficaz na coloração de formas parasitárias de Eimeria spp, sendo que HemacolorÒ prevaleceu pela rapidez (3 min.) sem deterioração da qualidade. Este meio de diagnóstico poderá ser considerado como ferramenta prática em espécies cinegéticas, carecendo de mais experiências e ensaios. Estas colorações poderão não ser úteis na identificação de protozoários flagelados, ainda que permitam a observação de parasitas sem necessária identificação da motilidade. Ainda se pôde concluir que a avaliação geral da saúde intestinal, de um ponto de vista holístico, se revela importante e crucial uma vez que a enterite bacteriana é frequentemente observada em aves cinegéticas, todavia deverá ser aprofundada a sua utilização em situação prática e laboratorial, de modo a aproximar todos os intervenientes do setor para um problema comum.
Nowadays, more than 30 million red-legged partridges are produced in Europe and in the USA. The upland game bird industry has an impact of $5.000 million and is a growing business. The production of these birds is made in semi-intensive systems and the main challenge are intestinal disorders, which represent about 84% of antibiotic prescriptions. The major intestinal diseases are caused by parasites, such as coccidia and protozoan flagellates. Although there is an extensive knowledge of these parasites, many aspects of the epidemiology and control remain unclear. Thus, a better understanding of the phenomena that interfere with microbiology, parasitology, pathophysiology and zootechnics is fundamental for the development of intestinal health promotion strategies. In this study, a protocol was implemented that integrated the four thematic previously described by following 2 batches of 2080 and 4400 partridges in the central region of France. The weekly assessment has included: measure of temperature and pH of the drinking water, bird behavior information, management changes, treatments and collection of 5 animals for laboratory analysis. In the laboratory, in each of the 3 main intestinal segments (duodenum, jejunum/ileum and cecum) was determined the parasite charge, the bacterial populations of Escherichia coli, Enterococcus spp., Campylobacter spp. and fungi were monitorized and photographies were taken for later analysis and evaluation of gut alterations and lesions. Colorations of the gut mucosa/content smears were also performed in order to understand and evaluate their use in a practical environment. The results of this study revealed that the monitoring of water temperature and pH is important, with cooler temperatures (equal to or less than 24 ° C) and acidic pH values (between 3 and 4) appearing to contribute for bird quality. Some management parameters such as the age of release for the flight pen, body condition and use of treatments seem to be good indicators of flock quality. Regarding to parasite infections, it was confirmed that the epidemiology and control of these parasites remain poorly understood, since the treatments and the clinical features did not corroborate with what´s described. Ineffective treatments and at the same time animals with obvious intestinal signs of coccidiosis were observed in birds without behavior alterations with good body condition and no mortality. Antibiotic treatments appeared to positively influence the existence of fungi in all intestinal segments and the access to the flight pen appeared to determine the presence and charge of Campylobacter spp. in all gut. Monitoring of Gram-negative and Gram-positive populations by staining intestinal contents was not possible, because of the heterogeneity and difficulty in the microscopical observation. In spite of this, this staining was useful in the identification of bacteria with atypical morphologies, such as the genus Sarcina and spiral/curved bacteria, which appear to develop during aggressive gastrointestinal alterations. The use of MayGrunwald-Giemsa and HemacolorÒ staining was very successful in the staining of parasitic forms of Eimeria spp. HemacolorÒ had a better performance since it is very quick (3 min.) with good quality. This type of diagnosis can be considered as a practical tool in game bird production, lacking more experiments and trials. These stains may not be useful in the identification of flagellated protozoa, although they allow the observation of parasites without necessary identification of the motility. It was possible to conclude that the intestinal health evaluation, from a holistic point of view is important and crucial since bacterial enteritis is frequently observed in game birds but its use should be further investigated in practical and laboratory situation, in order to approach all participants in the industry to a common problem.
Nowadays, more than 30 million red-legged partridges are produced in Europe and in the USA. The upland game bird industry has an impact of $5.000 million and is a growing business. The production of these birds is made in semi-intensive systems and the main challenge are intestinal disorders, which represent about 84% of antibiotic prescriptions. The major intestinal diseases are caused by parasites, such as coccidia and protozoan flagellates. Although there is an extensive knowledge of these parasites, many aspects of the epidemiology and control remain unclear. Thus, a better understanding of the phenomena that interfere with microbiology, parasitology, pathophysiology and zootechnics is fundamental for the development of intestinal health promotion strategies. In this study, a protocol was implemented that integrated the four thematic previously described by following 2 batches of 2080 and 4400 partridges in the central region of France. The weekly assessment has included: measure of temperature and pH of the drinking water, bird behavior information, management changes, treatments and collection of 5 animals for laboratory analysis. In the laboratory, in each of the 3 main intestinal segments (duodenum, jejunum/ileum and cecum) was determined the parasite charge, the bacterial populations of Escherichia coli, Enterococcus spp., Campylobacter spp. and fungi were monitorized and photographies were taken for later analysis and evaluation of gut alterations and lesions. Colorations of the gut mucosa/content smears were also performed in order to understand and evaluate their use in a practical environment. The results of this study revealed that the monitoring of water temperature and pH is important, with cooler temperatures (equal to or less than 24 ° C) and acidic pH values (between 3 and 4) appearing to contribute for bird quality. Some management parameters such as the age of release for the flight pen, body condition and use of treatments seem to be good indicators of flock quality. Regarding to parasite infections, it was confirmed that the epidemiology and control of these parasites remain poorly understood, since the treatments and the clinical features did not corroborate with what´s described. Ineffective treatments and at the same time animals with obvious intestinal signs of coccidiosis were observed in birds without behavior alterations with good body condition and no mortality. Antibiotic treatments appeared to positively influence the existence of fungi in all intestinal segments and the access to the flight pen appeared to determine the presence and charge of Campylobacter spp. in all gut. Monitoring of Gram-negative and Gram-positive populations by staining intestinal contents was not possible, because of the heterogeneity and difficulty in the microscopical observation. In spite of this, this staining was useful in the identification of bacteria with atypical morphologies, such as the genus Sarcina and spiral/curved bacteria, which appear to develop during aggressive gastrointestinal alterations. The use of MayGrunwald-Giemsa and HemacolorÒ staining was very successful in the staining of parasitic forms of Eimeria spp. HemacolorÒ had a better performance since it is very quick (3 min.) with good quality. This type of diagnosis can be considered as a practical tool in game bird production, lacking more experiments and trials. These stains may not be useful in the identification of flagellated protozoa, although they allow the observation of parasites without necessary identification of the motility. It was possible to conclude that the intestinal health evaluation, from a holistic point of view is important and crucial since bacterial enteritis is frequently observed in game birds but its use should be further investigated in practical and laboratory situation, in order to approach all participants in the industry to a common problem.