Metabolic alterations in broiler chickens experimentally infected with sporulated oocysts of Eimeria maxima

Abstract

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 5×10 3 sporulated oocysts of Eimeria maxima. Ten birds per sample were sacrificed on the 6 th , 11 th , 22 nd and 41 st 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.Keywords: Eimeria maxima, metabolism, experimental infection. ResumoForam 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 5×10 3 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.Palavras-chave: Eimeria maxima, metabolismo, infecção experimental.

The in vitro and in vivo anti-virulent effect of organic acid mixtures against Eimeria tenella and Eimeria bovis

“…The unique characteristics of Eimeria become evident once sporulation occurs and is able of producing infections at this stage 32,33 . Infection by sporulated E. maxima in chickens damaged intestinal villi and reduced nutrient absorption and performance 34 . While some natural antimicrobials were known to be effective against Eimeria spp., the impact on sporulated cells remained unknown 35 .…”

Explanations for keel bone fractures in laying hens: are there explanations in addition to elevated egg production?

“…If hens are fed to the recommended dietary quantities of calcium and phosphorous with adequate supply of vitamin D, further supplementation has limited effect ( Rennie et al., 1997 ). In practice, there is still the possibility of poor diet formulation, differences in the digestibility of the calcium source ( Guinotte et al., 1995 ; Anwar et al., 2016 ), or malabsorption of nutrients owing to factors such as poor gut health ( Freitas, 2014 ), although there seems to be little investigation of laying hens in this regard.…”