Effects of dietary supplementation with n-3 fatty acid ethyl esters on coccidiosis in chickens

n-3 enriched Fish oil diet enhanced intestinal barrier integrity in broilers after Eimeria infection

Coccidiosis caused by Eimeria spp. results in substantial economic losses in the poultry industry. The objective of this study was to investigate the effects of dietary supplementation with n-3 polyunsaturated fatty acids-enriched fish oil on growth performance, intestinal barrier integrity, and intestinal immune response of broilers challenged with Eimeria spp. A total of 576 fourteen-day-old broilers were randomly assigned in a completely randomized design with a 3 × 2 factorial arrangement, comprising 2 diets supplemented with either 5% fish oil or 5% soybean oil, and 3 Eimeria spp. infection levels: a nonchallenge control, a low dose of Eimeria challenge, and a high challenge dose. The results of the study revealed significant interactions between diet and Eimeria challenge to parameters of gut barrier integrity and feed intake. A significant interaction was observed in feed intake between 5 and 8 d postinfection (DPI), where the fish oil groups exhibited a higher amount of feed intake compared to the soybean oil diet groups after coccidiosis infection. The effects of the fish oil diet resulted in enhanced gut barrier integrity, as evidenced by a trend of decreased gastrointestinal leakage and a lower mean of small intestine lesion scores after Eimeria challenge. Additionally, significant interactions were noted between Eimeria spp. challenge and diet regarding jejunal crypt depth. The positive impact of the fish oil diet was particularly noticeable with the high Eimeria challenge dose. Overall, these findings underscore the relationship between the fish oil diet and Eimeria challenge on broiler chicken intestinal health. Dietary supplementation of fish oil has the potential to maintain small intestine barrier integrity with severe Eimeria infection conditions.

Omega-3 and omega-6 polyunsaturated fatty acids and their potential therapeutic role in protozoan infections

Protozoa exert a serious global threat of growing concern to human, and animal, and there is a need for the advancement of novel therapeutic strategies to effectively treat or mitigate the impact of associated diseases. Omega polyunsaturated fatty acids (ω-PUFAs), including Omega-3 (ω-3) and omega-6 (ω-6), are constituents derived from various natural sources, have gained significant attention for their therapeutic role in parasitic infections and a variety of essential structural and regulatory functions in animals and humans. Both ω-3 and ω-6 decrease the growth and survival rate of parasites through metabolized anti-inflammatory mediators, such as lipoxins, resolvins, and protectins, and have both in vivo and in vitro protective effects against various protozoan infections. The ω-PUFAs have been shown to modulate the host immune response by a commonly known mechanism such as (inhibition of arachidonic acid (AA) metabolic process, production of anti-inflammatory mediators, modification of intracellular lipids, and activation of the nuclear receptor), and promotion of a shift towards a more effective immune defense against parasitic invaders by regulation the inflammation like prostaglandins, leukotrienes, thromboxane, are involved in controlling the inflammatory reaction. The immune modulation may involve reducing inflammation, enhancing phagocytosis, and suppressing parasitic virulence factors. The unique properties of ω-PUFAs could prevent protozoan infections, representing an important area of study. This review explores the clinical impact of ω-PUFAs against some protozoan infections, elucidating possible mechanisms of action and supportive therapy for preventing various parasitic infections in humans and animals, such as toxoplasmosis, malaria, coccidiosis, and chagas disease. ω-PUFAs show promise as a therapeutic approach for parasitic infections due to their direct anti-parasitic effects and their ability to modulate the host immune response. Additionally, we discuss current treatment options and suggest perspectives for future studies. This could potentially provide an alternative or supplementary treatment option for these complex global health problems.

Performance and antioxidant traits of broiler chickens fed with diets containing rapeseed or flaxseed oil and optimized quercetin

This study evaluated the effect of quercetin (Q) added to feed mixtures, at concentrations directly optimized for the peroxidability of dietary rapeseed (RO) and flaxseed oil (FLO), on performance and selected biomarkers of oxidative stress of broiler chickens. Ninety-six one-day-old Ross 308 broiler chicken males were randomly assigned to four groups (six replicates per treatment, four birds per cage, n = 24 per group): Group RO received diets containing rapeseed oil (RO) and group FLO received diets containing flaxseed oil (FLO); Group RO_Q and group FLO_Q received these same diets containing RO or FLO oils, supplemented with optimized quercetin (Q). Blood, pectoral muscles, and liver samples of chickens were collected after 35 days to determine: (1) the global indicators of antioxidant capacity: ferric reducing antioxidant power (FRAP), antiradical activity (DPPH·/ABTS·+), total antioxidant status (TAS), and glutathione peroxidase (GSH-Px); (2) the activity of the antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD); and (3) the concentration of malondialdehyde (MDA). Data showed that the FLO diet did not affect the final performance parameters in relation to RO, but the optimized Q tended to improve the total body weight gain and the final body weight of broiler chickens (P = 0.10). The antioxidant traces analyzed in the blood (GSH-Px), plasma (FRAP, ABTS·+, DPPH·, TAS), serum (DPPH·), and pectoral muscles (SOD, CAT) of chickens were not altered by either Oil or Q factor. FLO supplementation increased MDA content in the liver of chickens (P < 0.05) and increased liver CAT activity, which was not improved by optimized Q. Meanwhile, the Oil × Q interaction suggests that optimized Q could reduce the liver burden and negative effects of oxidized lipid by-products associated with FLO diets. Our results indicate that optimizing the addition of natural polyphenols to feed may be a valuable alternative to the application of polyphenolic antioxidants in animal nutrition, allowing for an economical use of the antioxidant additives when customized to the peroxidability of fat sources, which is line to the conception of sustainable development covering 'The European Green Deal' and 'Farm to Fork Strategy'.

Reduction of macrophages by carrageenan decreases oocyst output and modifies local immune reaction in chick cecum with Eimeria tenella

This study aimed to evaluate the disease severity and local immune responses in macrophage-depleted chicks with Eimeria tenella. Macrophages were reduced by intraperitoneal injection of a carrageenan solution at 12, 13, and 16 days old, whereas the control group received intraperitoneal phosphate-buffered saline. Both chick groups were orally inoculated with E. tenella sporulated oocysts at 14 days old. Feces were collected daily, which were then quantified for oocysts. The chicks were sacrificed on day 5, and the ceca were collected for histopathological observation. The gene expression levels were measured using real-time quantitative reverse transcription-polymerase chain reaction. Macrophage-depleted chicks have been observed to shed a significantly reduced number of fecal oocysts compared to the infected control group. The parasite burden score in cecum specimens of macrophage-depleted chicks was significantly lower than those of infected control on day 5 after infection. Furthermore, macrophage reduction yielded significantly lower cecum histopathological scores and CD4 expression than those of the infected control group. The expression of interleukin (IL)-18, IL-22, interferon-γ, and inducible nitric oxide synthase was also noted to be significantly upregulated in both infected control and macrophage-depleted chicks compared to uninfected chicks. IL-4, IL-13, IL-17, and perforin expressions were also higher with macrophage depletion than in both control groups. These results suggest that macrophages serve as an invasive gate or a transporting vehicle to the site of first merogony. Furthermore, mononuclear phagocytes may play an important role in local immune responses, thus contributing to parasite development during early E. tenella infection.

In Vitro Anticoccidial Activity of Olive Pulp (Olea europaea L. var. Chemlal) Extract Against Eimeria Oocysts in Broiler Chickens

AIM

The objective of the present study was to investigate in vitro anticoccidial effect of olive pulp (Olea europaea L var. Chemlal) extract on the destruction of Eimeria spp. oocysts isolated from infected chickens naturally.

MATERIALS AND METHODS

The olive pulp (OP) powder was stirred manually in aqueous ethanol in preparation for extraction using the microwave-assisted extraction system. The identification of the phenolic compounds was obtained by ultra-high-performance liquid chromatography-mass spectrometry with electrospray ionisation (HPLC-ESI-MS). The treatment of Eimeria oocyst with OP extract and standard compounds (quercetin and oleuropein) leads to their lysis as shown by the release of substances absorbing at 273 nm.

RESULTS

Our results showed that the maximum number of reduced oocysts was recorded after 8 h of incubation of optimum OP extract, quercetin and oleuropein for different periods of time. Also, the number of Eimeria oocysts decreased considerably with increase concentrations after adding the optimum of OP extract in concentration ranging from 0.023 to 0.371 mg/ml. Positive correlation between the optimum OP extract concentrations and the number of Eimeria oocysts reduced was R² = 0.959. From this in vitro experiment, it can be concluded that the OP extract possesses an anti-Eimeria spp activity.

CONCLUSION

To our knowledge, this is the first time that quercetin and oleuropein were tested to evaluate their anticoccidial activity. The findings of this study showed that phenolic compound of OP extract tested separately possesses anti-Eimeria spp. effect. Further studies should be carried out to test its in vivo efficacy of the OP bioactive compounds in broiler chickens.

Influence of grape seed proanthocyanidin extract in broiler chickens: effect on chicken coccidiosis and antioxidant status

Grape seed proanthocyanidin extract (GSPE) has been widely used as a human food supplement for health promotion and disease prevention. However, there was little information regarding its application in animal nutrition. The aim of the current study is to determine the effect of GSPE at different concentrations on chicken performance, and the status of antioxidant/oxidant system after the Eimeria tenella infection. In the first experiment, GSPE incorporated in the diet at 5, 10, 20, 40, and 80 mg/kg significantly decreased mortality and increased weight gain after the E. tenella infection, and the protective effect of GSPE was dose-dependent. The lowest mortality and the greatest growth gains were recorded in the group of birds fed with GSPE between 10 to 20 mg/kg. In the second experiment, 12 mg/kg of GSPE supplementation in the diet significantly reduced the mortality and lesion scores in birds after the infection with 5 x 10(4) and 1 x 10(5) oocysts of E. tenella. The weight gains also improved significantly. After the oral infection with 5 x 10(4) and 1 x 10(5) of E. tenella, analysis of the status of antioxidant/oxidant system revealed that plasma NO increased significantly from 7.11 to 21.31 micromol/L, plasma superoxide dismutase (SOD) decreased from 126.55 to 111.14 U/mL, and malondiadehyde increased, suggesting oxidative stress was increased in circulation. However, supplementation of 12 mg/kg GSPE reduced the level of plasma NO from 21.31 to 14.73 micromol/L and increased plasma SOD activities from 111.14 to 133.27 U/mL. The effects of incorporation of GSPE into the poultry diet on the concentration of plasma NO, malondiadehyde, and SOD indicated that the lower concentration of dietary GSPE was able to restore the balance of antioxidant/oxidant system that was exerted by the oxidative stress after the parasite infection. The current results suggested GSPE can act as an antioxidant in diet to improve the performance of broiler chickens and remedy the clinical symptoms caused by the oxidative stress of E. tenella infection.

Fatty acids and coccidiosis: effects of dietary supplementation with different oils on coccidiosis in chickens

This study was undertaken to investigate the effects of dietary oils on coccidiosis of chickens infected with Eimeria tenella. Five hundred and four 1-day-old male Arbor Acres chicks were randomly assigned to seven groups. Seven diets were supplemented with poultry oil at 25 and 45 g/kg, corn oil at 25 and 45 g/kg, fish oil at 25 and 45 g/kg, and without oils, respectively, from 1 to 42 days of age. Chickens were inoculated by gavage with 3 x 10(5) sporulated oocysts at 21 days of age. Diets supplemented with oils at 45 g/kg resulted in higher body weight gain than with oils at 25 g/kg or without oils. The packed cell volume in chicks fed with diets supplemented with poultry oil was lower than that in chicks fed with diets supplemented with fish oil, corn oil and without oil. Chickens fed with diets supplemented with poultry oil had higher mortality than that of chickens fed with diets without oil. At 7 days post infection, the chickens consuming fish or corn oil diets had lower levels of plasma carotenoids than those fed with poultry oil supplement or without oils. Fish oil supplementation increased serum interleukin-6 levels in chickens compared with poultry oil at 25 and 45 g/kg and corn oil at 25 g/kg. Fish oil or corn oil enhanced secretory IgA levels in the lumen of the caecum, and oil supplementation tended to decrease serum IgG levels. In conclusion, the diets supplemented with saturated fatty acids aggravated mortality in chickens infected with E. tenella. The deleterious effects on coccidiosis of the diets supplemented with poultry oils might be related to the decreased levels of caecal E. tenella antigen-binding-specific secretory IgA or serum IgG.

Recent advances in biology and immunobiology of Eimeria species and in diagnosis and control of infection with these coccidian parasites of poultry

Avian coccidiosis, an intestinal disease caused by protozoan parasites of the genus Eimeria, occurs worldwide. It is considered to be one of the most economically important diseases of domestic poultry. For many years, prophylactic use of anticoccidial feed additives has been the primary means of controlling coccidiosis in the broiler industry and has played a major role in the growth of this industry, which now can produce about 7.6 billion chickens annually. However, development of anticoccidial resistance has threatened the economic stability of the broiler industry. Although there has been little effort by the pharmaceutical industry to develop new anticoccidials, the mounting problem of drug resistance of Eimeria species has prompted major research efforts to seek alternative means of control through increased knowledge of parasite biology, host response, and nutritional modulation. As a consequence, important advancements have been made, particularly in defining parasite antigens that have potential use in vaccines, defining the Eimeria genome, understanding the immunology of coccidial infections, and the practical applications of live vaccines. This review describes the progress in these areas, most of which has occurred within the past 10 to 15 years.