Engormix/Poultry Industry/Technical articles
Arkansas Nutrition Conference 2021
The following technical article is related to the event::
Arkansas Nutrition Conference 2021

Nutrition and Coccidiosis

Published on: 8/4/2022
Author/s : Po-Yun Teng, Fernanda Castro, and Woo Kyun Kim / Department of Poultry Science, University of Georgia, Athens, GA, USA.
Coccidiosis is the most common parasitic disease caused by Eimeria spp., leading to over $14 billion economic loss worldwide annually (Blake et al., 2020). The most prevalent Eimeria spp. in poultry include E. tenella, E. maxima, E. acervulina, E. brunetti, E. necatrix, E. praecox, and E. mitis and have different level of pathogenicity and specific infection sites in the intestine (Cervantes et al., 2020). Eimeria spp. invade intestinal epithelial tissues and induce intestinal damage, causing inflammation, oxidative stress, hemorrhage, and diarrhea. Furthermore, coccidiosis causes reduction of growth performance, intestinal integrity, nutrient digestibility, and increase of mortality and mobility in poultry.
Nutrition strategies have been evaluated to mitigate detrimental impact of coccidiosis in poultry. Prebiotics, probiotics, enzymes, antioxidants, amino acids, vitamins and minerals have shown to reduce severity of intestinal damage and stimulate nutrient digestion and fast recovery of the intestinal damage and growth performance (Parker et al., 2007; Amerah and Ravindran, 2015; Bortoluzzi et al., 2018; Oxford and Selvaraj, 2019; Souza et al., 2020; Yadav et al., 2020; Castro et al., 2020ab; Teng et al., 2020a). In order to develop efficient nutrition strategies, understanding of Eimeria infection on gut health and nutrient digestibility is critical. Thus, this paper will discuss about 1) Eimeria infection on gut health; 2) Eimeria infection on nutrient digestibility; and 3) Roles of key amino acids in Eimeria challenged broilers.
Eimeria infection on gut health
Eimeria infection increases intestinal damage, lesion score, gut permeability, inflammation, and oxidative stress, and such detrimental effects are highly correlated with Eimeria oocytes ingested by chickens (Adedokun and Adeola, 2016; Rochell et al., 2016; Zhang et al., 2017; Sakkas et al., 2018; Teng et al., 2020b, 2021). Recently, Teng et al. (2020b) evaluated graded levels of mixed Eimeria challenge (E. maxima, E. tenella, and E. acervulina) on growth performance and gut health (gut permeability, intestinal morphology, lesion score, and intestinal tight-junction protein expression) in broilers. The authors found that increase of Eimeria challenge dose linearly reduced feed intake and body weight gain, and intestinal villi height (Fig. 1), whereas it increased lesion score and upregulated key tight junction proteins, claudin 1 and Jam2. Moreover, gut permeability linearly increased on 5-, 6-, and 7-days postinfection (dpi) when Eimeria oocysts challenge dose increased. However, the gut permeability was back to the normal on 9 dpi. The results indicate that Eimeria infection causes detrimental effects on growth performance and gut health.
Nutrition and Coccidiosis - Image 1
Eimeria infection on nutrient digestibility
Several studies have shown that Eimeria infection reduces nutrient digestibility (Persia et al., 2006; Sakkas et al., 2018; Rochell et al., 2016; Teng et al., 2020b, 2021). Rochell et al (2016) reported that the apparent ileal digestibility (AID) of amino acids, except tryptophan and glycine, was linearly reduced in response to graded E. acervulina challenge. A study by Teng et al. (2020b) showed that increased mixed Eimeria spp. infection linearly decreased AID of digestible energy (Fig. 2) and minerals, such as sodium, potassium, calcium, magnesium, and phosphorus. These results clearly show that Eimeria infection reduces nutrient digestion and absorption in broilers, resulting in growth performance loss.
The reduction of nutrient digestibility caused by Eimeria infection may be due to reduction of digestive enzyme secretion and nutrient transports expression in the intestine. It has been reported that the activity and expression of several key mucosal brush border enzymes, such as maltase, sucrose, aminopeptidase, sucrose isomaltase, and alkaline phosphatase, were considerably limited by Eimeria infection in the intestine of broilers (Adams et al., 1996; Paris and Wong, 2013; Su et al., 2015). In addition, Eimeria infection significantly inhibits the expression of nutrient transporters in the intestine (Su et al., 2014, 2015; Teng et al., 2021). E. acervulina and E. maxima reduced the expression of glucose transporters as well as amino acid transporters including neutral amino acid transporters, cationic amino acid transporters, and excitatory amino acid transporters in the intestine of broilers (Su et al., 2015). Teng et al. (2021) also reported that graded E. maxima infection linearly regulated glucose and amino acid transporters in the brush boarder and basolateral member of the intestine.
Nutrition and Coccidiosis - Image 2
Figure 2. Effects of graded Eimeria challenge on ileal digestible energy (Teng et al., 2020b).
Roles of key amino acids in Eimeria challenged broilers
It has been reported that specific amino acids exhibit beneficial effects on intestinal development, immunity, gut integrity and anti-oxidant defense system in broilers challenged with Eimeria spp. (Gottardo et al., 2016; Zhang et al., 2017; Bortoluzzi et al., 2018; Castro et al. 2020ab). Among key amino acids, the functional effects of methionine, threonine, glutamine, and arginine have gained attention to alleviate detrimental effects of Eimeria infection in broilers.
Methionine is the first limiting amino acid in corn and soybean-based diets for poultry and plays important roles in metabolic functions, including methyl group donors, sulfur donors, and formations of cysteine, glutathione (GSH), taurine, carnitine, and polyamine (Stipanuk, 2004; Bunchasak, 2009). Because Eimeria infection reduces methionine digestibility and increases oxidative stress and inflammation in the body (Persia et al., 2006; Rusell et al., 2016; Souza et al., 2020; Yadav et al., 2020; Teng et al., 2021), methionine supplementation may improve anti-oxidant defense via GSH and reduce oxidative stress. Chen et al. (2013) reported that methionine supplementation increased serum SOD activity and total antioxidant potential in broilers and turkeys (Chen et al., 2013; Jankowski et al., 2017). Castro et al. (2020a) found that methionine supplementation increased GSH in the liver of broilers infected with three Eimeria spp. (E. acervuline, E. tenella, and E. maxima), alleviating oxidative stress caused by Eimeria inflation.
Threonine is the third limiting amino acid and the major component of mucin in the intestine (Corzo et al., 2007; Faureet al., 2002). Because Eimeria infection causes intestinal damage and increases mucin production in the intestine, threonine is one of the important amino acids to maintain intestinal integrity and rapid recovery during and after Eimeria infection. Zhang et al (2017) reported that threonine deficiency significantly increased Eimeria oocysts shedding and gut leakage in 25X Eimeria vaccine challenged broilers, and increased supplementation of threonine from 0.48 to 0.96% improved intestinal integrity and reduced oocyst shedding. Kidd et al. (2003) also reported that increased threonine supplementation from 0.6 to 0.8% enhanced growth responses (body weight gain, feed intake, and feed conversion ratio) in broilers, regardless of mid-E. acervulina challenge (30,000 oocysts). Recently, Teng et al. (2021) found that 0.75% threonine supplementation in a low protein diet increased villus height and JAM2, a tight junction protein, in broilers challenged with mixed Eimeria spp. (E. acervulina, E. maxima, and E. tenella), suggesting that threonine supplementation can be a nutritional strategy to improve gut health in broilers under coccidiosis condition. Moreover, threonine is a critical amino acid regulating immunoglobin production and inflammatory responses. Increasing dietary threonine enhanced IgA secretion and reduce pro-inflammatory cytokines such as INF-γ and IL-1 β (Chen el al., 2017).
Glutamine is an important fuel source of enterocytes during cell proliferation and repairment particularly during inflammation, oxidative stress and challenge conditions and a key component of glutathione that plays an essential role in body antioxidant system (Rao and Samak, 2012; Bortoluzzi et al., 2018). It has been reported that dietary supplementation of glutamine improved growth performance and gut health in broilers (Yi et al., 2005; Waldroup et al., 2012; Luquetti et al., 2016; Oxford and Selvaraj, 2019). Yi et al. (2005) reported that 1% glutamine supplementation improved growth performance and intestinal development in broilers challenged with 40,000 oocysts of E. maxima. Oxford and Selvaraj (2019) also found that 1% glutamine supplementation increased villus height and villus height to crypt depth ratio and the gene expression of tight junction proteins, whereas there was no difference in growth performance among the treatments. Recently, Teng et al. (2021) reported that 0.75% glutamine supplementation in a low protein diet reversed detrimental effects of Eimeria infection on tight junction protein expression in broilers.
Arginine is an essential amino acid for poultry and has beneficial effects on body composition (fat, muscle, and bone metabolisms), oxidative stress, immunity, and gut health in poultry. Besides the muscle protein synthesis, arginine is an essential precursor of many key molecules in the body such as glutamate, glutamine, creatine, nitric oxide, proline, and polyamines (Ball et al., 2007; Khajali and Wideman, 2010; Castro et al., 2019). Moreover, arginine plays an important role in growth hormone (GH) secretion and consequently increases insulin-like growth factor (IGF-1), which regulates muscle accretion and bone development (Liu and LeRoith,1999; Corzo et al., 2003; Silva et al., 2012). In addition, it was reported that an abdominal fat deposition was limited in broilers fed additional arginine supplemented diet (Fouad et al., 2013). Dietary supplementation of arginine improved total body antioxidant capacity and increased key antioxidant system in the body, including glutathione and superoxide dismutase (Atakisi et al., 2009; Duan et al., 2015).
Eimeria infection significantly affects arginine metabolism in broilers; E. acervulina infection reduced plasma arginine and increased nitrogen oxide production via arginine degradation (Allen and Fetterer, 2000; Rochell et al., 2016). Arginine supplementation reduced oocysts shedding of Eimeria spp. (Allen 1999; Laika and Jahanian, 2017), suggesting that arginine may directly and indirectly influences Eimeria life cycle. Recently Teng et al. (2021) reported that dietary arginine supplementation in broilers fed a low protein diet significantly reduced gut permeability, indicating that arginine supplementation can be a nutritional strategy to improve gut health under coccidiosis condition. Castro et al. (2020b) evaluated the effect of different levels of arginine (1.04, 1.14, 1.24, 1.34, and 1.44%) on growth performance and gut health of broilers challenged with mixed Eimeria spp. Eimeria challenge adversely affected growth performance, intestinal integrity, and nutrient digestibility in broilers. The birds fed 1.44% arginine had significantly higher body weight gain compared to those fed 1.04%, and 1.34% arginine fed birds showed lower feed conversion ratio compared to those fed 1.04%. Moreover, the 1.34% arginine group had significantly higher the expression of the tight junction protein Zonula occludens-1 (ZO-1) at 6 days post-infection (dpi), whereas the 1.44% arginine group had the highest expression of ZO-1 and ZO-2 at 14 dpi, indicating that dietary arginine supplementation has positive effects on gut health in broilers under coccidiosis condition.
Coccidiosis is a common enteric disease caused by Eimeria species; it considerably reduces growth performance, nutrient digestibility, intestinal integrity, and gut health and increases mortality and economic loss for the poultry industry. Thus, nutrition strategies, such as supplementing pre- and probiotics, amino acids, and feed additives having anti-oxidant and anti-inflammatory properties, would improve growth performance and gut health in poultry. Moreover, precise determination of nutrient digestibility and requirements/functions of key amino acids under coccidiosis are essential to develop nutritional strategies to improve growth performance and alleviate negative effects of Eimeria infection in poultry.
Presented at the Arkansas Nutrition Conference, August 31st to September 2nd, 2021, Rogers, AR.

Bibliographic references

Author/s :
Dr. Kim is an Assistant Professor at Department of Poultry Science, University of Georgia. He received a B.Sc. in Animal Science from Konkuk University, South Korea and M.Sc. (Animal Science) and Ph.D. (Nutritional Science) from Pennsylvania State University. After his Ph.D., he worked as a postdoctoral fellow in Texas A & M and UCLA. Before his moving to University of Georgia, Dr. Kim was a faculty member of University of Manitoba. His research area is poultry nutrition and bone metabolism in poultry.
Views23Comments 0StatisticsShare