The Use of Dual-Energy X-Ray Absorptiometry to Assess the Impact ofEimeriaInfections in Broiler Chicks

Synergistic impact of Salmonella typhimurium and Eimeria spp. coinfection on turkey poults: Growth performance, salmonella colonization, and ceca microbiota insights

Salmonella contamination in poultry products is a significant concern due to its potential to cause severe economic losses and public health problems. On the other side, coccidiosis is induced by Eimeria (E.) species. involves the destruction of host intestinal epithelial cells and subsequent invasion of pathogens, resulting in performance reduction and enhanced pathogen infection in poultry and economic losses for the poultry industry. A study was conducted to evaluate the impact of Eimeria infection and Salmonella typhimurium (ST) on growth performance, Salmonella colonization, and ceca microbiota in turkey poult. A total of 420 one-day-old male turkey poults were randomly allocated into six treatments, with five replicated cages for each treatment, over a 21-day experimental period. The study followed a 2 × 3 factorial design. Treatments consisted of NC, negative control without any challenge; T1, challenged with 8000 oocysts of E. meleagrimitis and E. adenoeides at d 8; T2, challenged with 16,000 oocysts of E. meleagrimitis and E. adenoeides at d 8; T3, challenged with nalidixic acid-resistant Salmonella typhimurium (ST) at d 0; T4, challenged with ST at d 0 and 8000 oocysts of E. meleagrimitis and E. adenoeides at d 8; T5, challenged with ST at d 0 and 16,000 oocysts of E. meleagrimitis and E. adenoeides at d 8. The Eimeria challenge groups significantly reduced the BW compared to the non-challenge group (P < 0.001). The challenged groups decreased FI during 9-14 days of age (P < 0.01). Salmonella typhimurium did not affect BW entire trial period (P > 0.05). Gut permeability (GP) increased in the challenge groups compared to the NC group (P < 0.001). Both ST and Eimeria significantly decreased superoxide dismutase (SOD) in the liver (P < 0.01). The challenge groups had lower villus height (VH) and higher crypt depth (CD) compared to the NC group, resulting in decreased VH:CD ratio in the duodenum and jejunum (P < 0.01). The groups T1, T2, and T4 had significantly higher fat deposition than the NC group (P < 0.05). The coinfected groups (T4 and T5) had higher salmonella colonization in the spleen compared to the ST-infected group (T3, P < 0.05). The ST challenge significantly decreased alpha diversity, including pielou evenness and Shannon entropy (P < 0.05). The Proteobacteria phylum and Enterobacteriaceae family significantly increased in T5 compared to the NC, T1, T2, and T3 (P < 0.05). In conclusion, Eimeria infection negatively impacted growth, gut health, intestine barrier integrity, and histology, while Salmonella had a milder effect on performance. Coinfection with Salmonella and Eimeria spp. led to changes in gut microbiota and increased liver Salmonella colonization and fat deposition in turkey poults.

Effects of phytase and 25-Hydroxycholecalciferol supplementation in broilers fed calcium-phosphorous deficient diets, with or without Eimeria challenge, on growth performance, body composition, bone development, and gut health

The study evaluated the effects of nutritional strategies on broilers challenged with Eimeria from d 14 to 26. A total of 840 Cobb male broilers were fed five diets in a 2 × 5 factorial arrangement: 1) nutrient adequate diet (PC; 0.84% calcium [Ca], 0.42% available phosphorus [avP]); 2) Ca-P deficient diet (NC; 0.64% Ca, 0.22% avP); 3) NC + 1500 FTU/kg phytase of diet (NC + PHY); 4) NC + 5000 IU/kg 25-Hydroxycholecalciferol of diet (NC + 25OHD); and 5) NC with both supplements (NC + PHY + 25OHD), with and without Eimeria challenge. All treatments had six replicate cages with 14 birds per cage. At 5 days post inoculation (DPI), the challenged birds exhibited higher serum fluorescein isothiocyanate-d (FITC-d) levels than the unchallenged birds (P < 0.001). The NC + PHY and NC + PHY + 25OHD groups exhibited lower FITC-d levels compared to the NC + 25OHD group (P = 0.012). Significant interaction effects between Eimeria challenge and dietary treatments were observed on various parameters. During 0 to 6 and 0 to 12 DPI, Eimeria challenge resulted in decreased the body weight gain (BWG) (P < 0.05) but had a negative effect on the feed conversion ratio (FCR) in birds compared to the unchallenged group (P < 0.05). Reducing Ca and avP levels in the diet (NC) did not adversely affect BWG, but negatively impacted FCR, bone ash weight, ash concentration, and femur bone microstructure parameters (P < 0.05). On 12 DPI, Eimeria challenge led to decreased tibia bone weight, bone volume, fat-free bone weight (FFBW), and ash weight of birds (P < 0.05). Supplementation with phytase alone or in combination with 25OHD improved growth performance, gut permeability, bone ash and bone microstructure parameters in birds (P < 0.05). However, the group fed 25OHD alone showed enhancements on growth performance, mineral apposition rate (MAR), bone ash concentration and ash percentage of the birds (P < 0.05). In conclusion, lowering Ca and avP levels in the diet negatively affected FCR and bone development but did not affect intestinal integrity in broilers. Dietary supplementation of phytase, 25OHD, or phytase in combination of 25OHD could enhance the growth performance and bone quality of broilers infected with Eimeria. Notably, the benefits of phytase supplementation were generally more pronounced than those associated with 25OHD supplementation; however, the combination of phytase and 25OHD could induce optimum effects.

Different methionine to cysteine supplementation ratios altered bone quality of broilers with or without Eimeria challenge assessed by dual energy X-ray absorptiometry and microtomography

Despite the acknowledged significance of nutrition in bone development, effects of methionine (Met) and cysteine (Cys) on bone quality remain under-researched, particularly during Eimeria challenge. We investigated the effects of different supplemental Met to Cys ratios (MCR) on bone quality of broilers under Eimeria challenge. A total of 720 fourteen-day old Cobb500 broilers were allocated into a 5 × 2 factorial arrangement. Five diets with Met and Cys supplemented at MCR of 100:0, 75:25, 50:50, 25:75, and 0:100 were fed to the birds with or without Eimeria challenge. Body composition was measured by dual energy x-ray absorptiometry, and the femur bone characteristics were assessed by microtomography. Data were analyzed by two-way ANOVA and orthogonal polynomial contrast. The results reaffirmed the detrimental effects of Eimeria challenge on bone quality. On 9 d post inoculation (DPI), significant interaction effects were found for whole body bone mineral content (BMC), lean tissue weight, and body weight (P < 0.05); in the nonchallenged group (NCG), these parameters linearly decreased as MCR decreased (P < 0.05). In the challenged group (CG), body weight and lean tissue weight were unaffected by MCR, and BMC linearly increased as MCR decreased (P < 0.05). For the cortical bone of femoral metaphysis on 6 DPI, bone mineral density (BMD) linearly increased as MCR decreased (P < 0.05). Bone volume to tissue volume ratio (BV/TV) in the CG linearly increased as MCR decreased (P < 0.05). On 9 DPI, BMC and TV linearly increased as MCR decreased (P < 0.05) in the NCG. BMD and BV/TV changed quadratically as MCR decreased (P < 0.05). For the trabecular bone of femoral metaphysis on 9 DPI, BV/TV, and trabecular number linearly increased as MCR decreased (P < 0.05) in the NCG. For the femoral diaphysis, BV, TV, BMC on 6 DPI, and BMD on 9 DPI linearly increased as MCR decreased (P < 0.05). In conclusion, this study showed that both Eimeria challenge and varying supplemental MCR could influence bone quality of broilers.

Reduced bone formation and increased bone resorption drive bone loss in Eimeria infected broilers

Coccidiosis is an economically significant disease in the global poultry industry, but little is known about the mechanisms of bone defects caused by coccidiosis; thus, the study focused on effects of coccidiosis on the bone homeostasis of young broiler chickens. A total of 480 male Cobb500 broilers were randomly allocated into four treatment groups, including an uninfected control consuming diet ad libitum, two infected groups were orally gavaged with two different concentrations of sporulated Eimeria oocysts, and an uninfected pair-fed group fed the same amount of feed as the high Eimeria-infected group consumed. Growth performance and feed intake were recorded, and samples were collected on 6 days post infection. Results indicated that coccidiosis increased systemic oxidative status and elevated immune response in bone marrow, suppressing bone growth rate (P < 0.05) and increasing bone resorption (P < 0.05) which led to lower bone mineral density (P < 0.05) and mineral content (P < 0.05) under Eimeria infection. With the same amount of feed intake, the uninfected pair-fed group showed a distinguished bone formation rate and bone resorption level compared with the Eimeria infected groups. In conclusion, inflammatory immune response and oxidative stress in broilers after Eimeria infection were closely associated with altered bone homeostasis, highlighting the role of inflammation and oxidative stress in broiler bone homeostasis during coccidiosis.

Long Bone Mineral Loss, Bone Microstructural Changes and Oxidative Stress After Eimeria Challenge in Broilers

The objective of this study was to evaluate the impact of coccidiosis on bone quality and antioxidant status in the liver and bone marrow of broiler chickens. A total of 360 13-day old male broilers (Cobb 500) were randomly assigned to different groups (negative control, low, medium-low, medium-high, and highest dose groups) and orally gavaged with different concentrations of Eimeria oocysts solution. Broiler tibia and tibia bone marrow were collected at 6 days post-infection (6 dpi) for bone 3-D structural analyses and the gene expression related to osteogenesis, oxidative stress, and adipogenesis using micro-computed tomography (micro-CT) and real-time qPCR analysis, respectively. Metaphyseal bone mineral density and content were reduced in response to the increase of Eimeria challenge dose, and poor trabecular bone traits were observed in the high inoculation group. However, there were no significant structural changes in metaphyseal cortical bone. Medium-high Eimeria challenge dose significantly increased level of peroxisome proliferator-activated receptor gamma (PPARG, p < 0.05) and decreased levels of bone gamma-carboxyglutamate protein coding gene (BGLAP, p < 0.05) and fatty acid synthase coding gene (FASN, p < 0.05) in bone marrow. An increased mRNA level of superoxide dismutase type 1 (SOD1, p < 0.05) and heme oxygenase 1 (HMOX1, p < 0.05), and increased enzyme activity of superoxide dismutase (SOD, p < 0.05) were found in bone marrow of Eimeria challenged groups compared with that of non-infected control. Similarly, enzyme activity of SOD and the mRNA level of SOD1, HMOX1 and aflatoxin aldehyde reductase (AKE7A2) were increased in the liver of infected broilers (p < 0.05), whereas glutathione (GSH) content was lower in the medium-high challenge group (p < 0.05) compared with non-challenged control. Moreover, the mRNA expression of catalase (CAT) and nuclear factor kappa B1 (NFKB1) showed dose-depend response in the liver, where expression of CAT and NFKB1 was upregulated in the low challenge group but decreased with the higher Eimeria challenge dosage (p < 0.05). In conclusion, high challenge dose of Eimeria infection negatively affected the long bone development. The structural changes of tibia and decreased mineral content were mainly located at the trabecular bone of metaphyseal area. The change of redox and impaired antioxidant status following the Eimeria infection were observed in the liver and bone marrow of broilers.

Technological Advances in Diagnostic Imaging in Exotic Pet Medicine

Diagnostic imaging relies on interpretation of interactions between the body tissue and various energies, such as x-rays, ultrasound, and magnetic or nuclear energies, to differentiate normal from abnormal tissues. Major technological improvements regarding emission and detection of the energetic waves, as well as reconstruction and interpretation of the images, have occurred. These advances made possible visualization of smaller structures, quantitative evaluation of functional processes, and development of unique imaging-guided procedures. This article reviews the technological advances that allowed development of cone beam computed tomography, dual-energy x-ray absorptiometry, and contrast-enhanced ultrasonography, which all could have applications in exotic pet medicine.

Dietary vitamin D improves performance and bone mineralisation, but increases parasite replication and compromises gut health in Eimeria-infected broilers

Coccidial infections reduce fat-soluble vitamin status and bone mineralisation in broiler chickens. We hypothesised that broilers infected with Eimeria maxima would benefit from increased dietary supplementation with vitamin D (vitD) or with 25-hydroxycholecalciferol (25(OH)D3 or 25D3). Broilers were assigned to diets with low (L) or commercial (M) vitD levels (25 v. 100 μg/kg) supplemented as cholecalciferol (D3) or 25D3. At day 11 of age, birds were inoculated with water or 7000 E. maxima oocysts. Pen performance was calculated over the early (days 1-6), acute (days 7-10) and recovery periods (days 11-14) post-infection (pi). At the end of each period, six birds per treatment were dissected to assess long bone mineralisation, plasma levels of 25D3, Ca and P, and intestinal histomorphometry. Parasite replication and transcription of cytokines IL-10 and interferon-γ (IFN-γ) were assessed at day 6 pi using quantitative PCR. Performance, bone mineralisation and plasma 25D3 levels were significantly reduced during infection (P < 0·05). M diets or diets with 25D3 raised plasma 25D3, improved performance and mineralisation (P < 0·05). Offering L diets compromised feed efficiency pi, reduced femur breaking strength and plasma P levels at day 10 pi in infected birds (P < 0·05). Contrastingly, offering M diets or diets with 25D3 resulted in higher parasite loads (P < 0·001) and reduced jejunal villi length at day 10 pi (P < 0·01), with no effect on IL-10 or IFN-γ transcription. Diets with M levels or 25D3 improved performance and mineralisation, irrespective of infection, while M levels further improved feed efficiency and mineralisation in the presence of coccidiosis.

Does selection for growth rate in broilers affect their resistance and tolerance to Eimeria maxima?

Chickens exhibit varied responses to infection with Eimeria parasites. We hypothesise that broilers selected for increased growth rate will show lower resistance and tolerance to a coccidian challenge. 288 chickens of fast (F) or slow (S) growing lines were inoculated with 0 (control), 2500 (low-dose), or 7000 (high-dose) sporulated E. maxima oocysts at 13 days of age in two consecutive rounds. Gain and Intake were measured daily and their values relative to BW at the point of infection were calculated over the pre-patent (days 1-4 post-infection), acute (d5-8 pi), and recovery (d9-12 pi) phases of infection to assess the impact of infection. Levels of plasma carotenoids, vitamins E and A, long bone mineralisation, caecal microbiota diversity indices, and histological measurements were assessed at the acute (d6 pi) and recovery stage (d13 pi). In addition, we measured the levels of nitric oxide metabolites and the number of parasite genome copies in the jejunumat d6pi. In absolute terms F birds grew 1.42 times faster than S birds when not infected. Infection significantly reduced relative daily gain and intake (P < 0.001), with the effects being most pronounced during the acute phase (P < 0.001). Levels of all metabolites were significantly decreased, apart from NO which increased (P < 0.001) in response to infection on d6pi, and were accompanied by changes in histomorphometric features and the presence of E. maxima genome copies in infected birds, which persisted to d13pi. Furthermore, infection reduced tibia and femur mineralisation, which also persisted to d13pi. Reductions in measured variables were mostly independent of dose size, as was the level of parasite replication. The impact of infection was similar for S and F-line birds for all measured parameters, and there were no significant interactions between line x dose size on any of these parameters. In conclusion, our results suggest that line differences in productive performance do not influence host responses to coccidiosis when offered nutrient adequate diets.