Correlation between intestinal health and coccidiosis prevalence in broilers in Brazilian agroindustries.

Coccidiosis is caused by protozoa of the genus Eimeria. These are intracellular parasites of enterocytes that rupture the host cell, causing lesions in the intestinal mucosa. The lesions caused by Eimeria reduce nutrient absorption capacity, negatively affecting productive gains in broilers, and representing a gateway for other enteropathogens. The objective of this study was to analyze the correlation between lesions caused by Eimeria and the prevalence of coccidiosis and other alterations found in the gastrointestinal tracts of broilers produced in Brazil from 2017 to 2018. Intestinal health evaluations were performed in 32 integrations (farm) of broilers in Brazil, totaling 726 birds analyzed between the ages of 22 and 40 days. Necropsied chickens were collected at three different points, with at least three birds per shed. We analyzed the following changes in the gastrointestinal tract: presence of cellular desquamation, fluid and mucus excess, ingestion of bedding, small and large intestine lesion, food passage, altered tone, "Turkish towel" lesions, worm infection, enteritis and gizzard erosion. The definition of macroscopic lesion scores caused by Eimeria acervulina, Eimeria maxima, Eimeria tenella followed a specific methodology. Mucosal oocyst counts for E. maxima (E. maxima micro) was performed using an optical microscope with a magnification of 100×. We found that the species E. acervulina had the highest prevalence (5.5%). With respect to E. acervulina, a positive correlation was observed with cellular desquamation, bedding ingestion and passage of food. The second highest prevalence was E. maxima (average of 4%), showing positive correlations with cellular desquamation, fluid excess, bed ingestion, feed passage and E. acervulina. E. tenella represented the lowest prevalence (0.8%) among the species of Eimeria analyzed, showing a positive correlation with altered intestinal tone. On microscopic evaluation, E. maxima was present in 45% of mucosa scrapings, representing subclinical coccidiosis of 1125% (11.25-fold) greater than the rate of clinical coccidiosis. Regarding other alterations that were visualized in the gastrointestinal tract, we have recorded the incidence of altered intestinal tone (0.1%), worm infection (0.4%), small intestine (0.8%), enteritis (1%), duodenitis (1.5%), "Turkish towel" lesions (3.3%), excess fluid (4.5%), bed ingestion (6.9%), excess mucus (8.4%), food passage (10.3%), cellular desquamation (11%) and gizzard erosion (13.4%). We conclude that monitoring is of paramount importance to understand the intestinal health status of poultry lots. Microscopic E. maxima is present in 45%. We identified factors that correlate with reduction in intestinal health, impairing zoo-economic performance.

Bacillus amyloliquefaciens CECT 5940 alone or in combination with antibiotic growth promoters improves performance in broilers under enteric pathogen challenge.

A study was conducted to investigate the effects of Bacillus amyloliquefaciens CECT 5940 as a direct-fed microbial (DFM) alone or in association with bacitracin methylene disalicylate (BMD) in broilers under enteric pathogen challenge. A total of 1,530-day-old male Cobb500 chicks were randomly assigned to 5 treatments, with 9 replicate pens with 34 birds each. Treatments included positive control (PC, basal diet without additives or challenge); negative control (NC, basal diet without additive and challenged birds); NC + 0.05 g/kg BMD; NC + 1 g/kg DFM (106 CFU B. amyloliquefaciens CECT 5940/g of feed); and NC + 0.05 g/kg BMD + 1 g/kg DFM. The challenge consisted of oral gavage with Eimeria maxima and Clostridium perfringens inoculum. Body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR) were evaluated on days 21, 35, and 42. Ileal and cecal content were collected on days 21 and 28 for C. perfringens enumeration by real-time PCR assay and the intestinal health was evaluated by scores. Uniformity (UN), carcass (CY), and breast meat yields (BMY) were evaluated on day 42. After 14 and 21 d post-inoculation, birds in the challenged groups had significant lower FI and BWG compared to the PC group (P < 0.05). However, the groups receiving DFM, BMD, or its combination presented better FCR, CY, BMY, UN, and lower incidence of footpad lesion and litter quality visual scores, compared to the NC group without feed additives (P < 0.05). Mortality was not affected by treatments (P > 0.05). Broilers fed DFM, BMD, or its combination presented lower C. perfringens in ileal content at 21 and 28 d compared to NC group without additives (P < 0.05) and also maintained gut health by keeping the frequency of ballooning, abnormal content, and swollen mucosa comparable to the PC group (P > 0.05). The study indicates that Bacillus amyloliquefaciens CECT 5940 is effective as BMD to provide similar performance and gut health in challenged broilers.

Nutrient digestibility parameters as a tool for analysis of the intestinal health of broiler chickens / Ensaio de digestibilidade de nutrientes como ferramenta para avaliar a saúde intestinal de frangos de corte

The study was performed with the objective of verifying raw soy feed, oxidized oil feed, and a control group. Performance evaluation was done at 7, 14, and 21 days of age. Metabolism assay was carried out between the 17th and 20th days for nutrient digestibility analysis. On the 21st day, two birds per repetition were sent for necropsy and collection of intestine fragments (duodenum and jejunum) for histomorphometric analysis. Eight to 14 days after treatment with Salmonella, individuals showed lower feed intake and feed conversion than the control group. Treatment with coccidiosis decreased all performance parameters in the control. Raw soybeans and oxidized oil induce lower weight gain and higher feed conversion compared to the control feed. Unlike after 14 days, at 21 days treatment with salmonella a decrease in weight gain was noted. For the group challenged by coccidiosis feed intake, the feed conversion remained lower than the control group. Undesirable effects on performance in the groups fed raw soybean and oxidized oil remained at up to 21 days. In the evaluation of digestibility, it was observed that raw soy had lower values for digestibility of dry matter, ether extract, and nitrogen balance due to intake. In addition, a lower ratio of villus:crypt measurements was observed. Lower villus height was found in the duodenum of the group challenged by coccidiosis. This gr

O experimento foi realizado com o objetivo de verificar os alimentos soja cru, óleo oxidado e um grupo controle. Foi avaliado o desempenho aos sete, 14 e 21 dias de idade. Foi realizado um ensaio de metabolismo do 17 ao 20 dia, para análise da digestibilidade dos nutrientes. No 21º dia, duas aves por repetição foram enviadas para necropsia e coleta de fragmentos do intestino (duodeno e jejuno) para análise da histomorfometria. De oito a 14 dias de idade o tratamento com Salmonella apresentou menor consumo de ração e conversão alimentar que o grupo controle. O tratamento com coccidiose apresentou redução em todos os parâmetros de desempenho em relação ao controle. A soja crua e o óleo oxidado apresentaram menores ganhos de peso e alta conversão alimentar em relação ao controle. Aos 21 dias o tratamento com Salmonella diferentemente dos 14 dias apresentou queda no ganho de peso. Para o grupo desafiado por coccidiose o consumo de ração e a conversão alimentar continuaram menores que o grupo controle. Os efeitos indesejáveis sobre o desempenho nos grupos alimentados com soja crua e óleo oxidado permaneceram até os 21 dias. Na avaliação dos coeficientes de digestibilidade, foi observado que a soja crua apresentou menores valores para digestibilidade da matéria seca, extrato etéreo e balanço de nitrogênio em função da ingestão. Além disso, foi observada uma menor relação vilo:cript

Nutrient digestibility parameters as a tool for analysis of the intestinal health of broiler chickens / Ensaio de digestibilidade de nutrientes como ferramenta para avaliar a saúde intestinal de frangos de corte

The study was performed with the objective of verifying raw soy feed, oxidized oil feed, and a control group. Performance evaluation was done at 7, 14, and 21 days of age. Metabolism assay was carried out between the 17th and 20th days for nutrient digestibility analysis. On the 21st day, two birds per repetition were sent for necropsy and collection of intestine fragments (duodenum and jejunum) for histomorphometric analysis. Eight to 14 days after treatment with Salmonella, individuals showed lower feed intake and feed conversion than the control group. Treatment with coccidiosis decreased all performance parameters in the control. Raw soybeans and oxidized oil induce lower weight gain and higher feed conversion compared to the control feed. Unlike after 14 days, at 21 days treatment with salmonella a decrease in weight gain was noted. For the group challenged by coccidiosis feed intake, the feed conversion remained lower than the control group. Undesirable effects on performance in the groups fed raw soybean and oxidized oil remained at up to 21 days. In the evaluation of digestibility, it was observed that raw soy had lower values for digestibility of dry matter, ether extract, and nitrogen balance due to intake. In addition, a lower ratio of villus:crypt measurements was observed. Lower villus height was found in the duodenum of the group challenged by coccidiosis. This gr

O experimento foi realizado com o objetivo de verificar os alimentos soja cru, óleo oxidado e um grupo controle. Foi avaliado o desempenho aos sete, 14 e 21 dias de idade. Foi realizado um ensaio de metabolismo do 17 ao 20 dia, para análise da digestibilidade dos nutrientes. No 21º dia, duas aves por repetição foram enviadas para necropsia e coleta de fragmentos do intestino (duodeno e jejuno) para análise da histomorfometria. De oito a 14 dias de idade o tratamento com Salmonella apresentou menor consumo de ração e conversão alimentar que o grupo controle. O tratamento com coccidiose apresentou redução em todos os parâmetros de desempenho em relação ao controle. A soja crua e o óleo oxidado apresentaram menores ganhos de peso e alta conversão alimentar em relação ao controle. Aos 21 dias o tratamento com Salmonella diferentemente dos 14 dias apresentou queda no ganho de peso. Para o grupo desafiado por coccidiose o consumo de ração e a conversão alimentar continuaram menores que o grupo controle. Os efeitos indesejáveis sobre o desempenho nos grupos alimentados com soja crua e óleo oxidado permaneceram até os 21 dias. Na avaliação dos coeficientes de digestibilidade, foi observado que a soja crua apresentou menores valores para digestibilidade da matéria seca, extrato etéreo e balanço de nitrogênio em função da ingestão. Além disso, foi observada uma menor relação vilo:cript

Metabolic alterations in broiler chickens experimentally infected with sporulated oocysts of Eimeria maxima / Alterações metabólicas em frangos de corte infectados experimentalmente com oocistos esporulados de Eimeria maxima

Metabolic and morphometric alterations of the duodenal villi caused by parasitism of chickens by Eimeria maxima were evaluated, using 100 male Cobb birds, randomly distributed into two groups (control and infected). The infected group was inoculated with 0.5 ml of a solution containing 5×103 sporulated oocysts of Eimeria maxima. Ten birds per sample were sacrificed on the 6th, 11th, 22nd and 41st days post-infection (dpi). In order to evaluate the alterations, samples of duodenum, jejunum and ileum fragments were collected after necropsy for histological analysis. Villus biometry was determined by means of a slide graduated in microns that was attached to a binocular microscope. To evaluate the biochemical data, 5 ml of blood were sampled from the birds before sacrifice. The statistical analyses were performed using the GraphPad 5 statistical software for Windows. Tukey's multiple comparison test (p <0.05) was performed for the different dpi's and the unpaired t test for the difference between the groups. Infection by E. maxima causes both qualitative and quantitative alterations to the structure of the intestinal villi, thereby interfering with the absorption of nutrients such as calcium, phosphorus, magnesium, protein and lipids, with consequent reductions in the birds' weights.

Foram avaliadas alterações metabólicas e morfométricas das vilosidades intestinais causadas pelo parasitismo de frangos por Eimeria maxima, sendo utilizadas 100 aves da linhagem Coob, machos, distribuídos aleatoriamente em dois grupos experimentais: grupo controle, inoculado com 0,5 ml de água destilada; grupo infectado, inoculado com 0,5ml de solução contendo 5×103 oocistos esporulados de Eimeria maxima. Foram sacrificadas 10 aves por coleta no 0, 6, 11, 22 e 41 dias pós-infecção. Para avaliar as alterações foram retiradas, após necropsia, amostras de fragmentos do duodeno, jejuno e íleo para análise histológica. A determinação da biometria de vilosidades foi realizada por meio de lâmina milimetrada acoplada a um microscópio binocular. Para avaliação dos dados bioquímicos foram coletados 5 ml de sangue das aves antes da eutanásia. As análises estatísticas foram realizadas, utilizando-se o programa estatístico Graphpad Prism. 5 Windows e realizado o teste de comparações múltiplas de Tukey (p <0,05) para os diferentes dpi's e o Teste T não Pareado para diferença entre os grupos. A infecção por E. maxima provoca alterações qualitativas e quantitativas das vilosidades intestinais, interferindo na absorção de nutrientes, como cálcio, fósforo, magnésio, proteínas e lipídios, com consequente redução no peso das aves.

Metabolic alterations in broiler chickens experimentally infected with sporulated oocysts of Eimeria maxima / Alterações metabólicas em frangos de corte infectados experimentalmente com oocistos esporulados de Eimeria maxima

Metabolic and morphometric alterations of the duodenal villi caused by parasitism of chickens by Eimeria maxima were evaluated, using 100 male Cobb birds, randomly distributed into two groups (control and infected). The infected group was inoculated with 0.5 ml of a solution containing 5×103 sporulated oocysts of Eimeria maxima. Ten birds per sample were sacrificed on the 6th, 11th, 22nd and 41st days post-infection (dpi). In order to evaluate the alterations, samples of duodenum, jejunum and ileum fragments were collected after necropsy for histological analysis. Villus biometry was determined by means of a slide graduated in microns that was attached to a binocular microscope. To evaluate the biochemical data, 5 ml of blood were sampled from the birds before sacrifice. The statistical analyses were performed using the GraphPad 5 statistical software for Windows. Tukey's multiple comparison test (p <0.05) was performed for the different dpi's and the unpaired t test for the difference between the groups. Infection by E. maxima causes both qualitative and quantitative alterations to the structure of the intestinal villi, thereby interfering with the absorption of nutrients such as calcium, phosphorus, magnesium, protein and lipids, with consequent reductions in the birds' weights.

Foram avaliadas alterações metabólicas e morfométricas das vilosidades intestinais causadas pelo parasitismo de frangos por Eimeria maxima, sendo utilizadas 100 aves da linhagem Coob, machos, distribuídos aleatoriamente em dois grupos experimentais: grupo controle, inoculado com 0,5 ml de água destilada; grupo infectado, inoculado com 0,5ml de solução contendo 5×103 oocistos esporulados de Eimeria maxima. Foram sacrificadas 10 aves por coleta no 0, 6, 11, 22 e 41 dias pós-infecção. Para avaliar as alterações foram retiradas, após necropsia, amostras de fragmentos do duodeno, jejuno e íleo para análise histológica. A determinação da biometria de vilosidades foi realizada por meio de lâmina milimetrada acoplada a um microscópio binocular. Para avaliação dos dados bioquímicos foram coletados 5 ml de sangue das aves antes da eutanásia. As análises estatísticas foram realizadas, utilizando-se o programa estatístico Graphpad Prism. 5 – Windows e realizado o teste de comparações múltiplas de Tukey (p <0,05) para os diferentes dpi's e o Teste T não Pareado para diferença entre os grupos. A infecção por E. maxima provoca alterações qualitativas e quantitativas das vilosidades intestinais, interferindo na absorção de nutrientes, como cálcio, fósforo, magnésio, proteínas e lipídios, com consequente redução no peso das aves.

Meta-analysis of the performance variation in broilers experimentally challenged by Eimeria spp.

A meta-analysis was carried out to (1) study the relation of the variation in feed intake and weight gain in broilers infected with Eimeria acervulina, Eimeria maxima, Eimeria tenella, or a Pool of Eimeria species, and (2) to identify and to quantify the effects involved in the infection. A database of articles addressing the experimental infection with Coccidia in broilers was developed. These publications must present results of animal performance (weight gain, feed intake, and feed conversion ratio). The database was composed by 69 publications, totalling around 44 thousand animals. Meta-analysis followed three sequential analyses: graphical, correlation, and variance-covariance. The feed intake of the groups challenged by E. acervulina and E. tenella did not differ (P>0.05) to the control group. However, the feed intake in groups challenged by E. maxima and Pool showed an increase of 8% and 5% (P<0.05) in relation to the control group. Challenged groups presented a decrease (P<0.05) in weight gain compared with control groups. All challenged groups showed a reduction in weight gain, even when there was no reduction (P<0.05) in feed intake (adjustment through variance-covariance analysis). The feed intake variation in broilers infected with E. acervulina, E. maxima, E. tenella, or Pool showed a quadratic (P<0.05) influence over the variation in weight gain. In relation to the isolated effects, the challenges have an impact of less than 1% over the variance in feed intake and weight gain. However, the magnitude of the effects varied with Eimeria species, animal age, sex, and genetic line. In general the age effect is superior to the challenge effect, showing that age at the challenge is important to determine the impact of Eimeria infection.