Xylanase and beta-glucanase improve performance parameters and footpad dermatitis and modulate intestinal microbiota in broilers under an Eimeria challenge.

Coccidiosis is an enteric disease of poultry worldwide that compromises gut health and growth performance. The current research investigated the effects of 2 doses of a multienzyme preparation on broilers' performance, gut health, and footpad dermatitis (FPD) under an Eimeria challenge. A total of 512 mixed-sex day-old chicks (Cobb 500) were randomly allocated to 4 treatments of 8 replicates. Treatments were: 1) nonchallenged control (NC); 2) NC + Eimeria challenge (CC); 3) CC + recommended level of xylanase and glucanase (XG, 100 g/t feed [on top]); 4) CC + double XG (2XG, 200 g/t feed). Eimeria spp. vaccine strains were gavaged on d 9 to induce coccidiosis in chickens. Performance parameters were evaluated during starter, grower, and finisher phases, and 4 birds per pen were euthanized on d 16 for sampling, FPD was scored on d 35, and litter moisture was analyzed on d 17 and 35. The data were analyzed using 1-way ANOVA with Tukey's test to separate means, and Kruskal-Wallis test was used for non-normally distributed parameters. The results showed that the Eimeria challenge was successful based on reduced weight gain and feed intake during grower phase, and higher FITC-d concentration, lesion score (female), and oocyst counts (d 14) in CC group compared to N.C. group, while XG and 2XG increased (P < 0.001) weight gain and improved FCR compared to CC and NC groups during finisher phase. The addition of X.G. and 2XG decreased litter moisture (P = 0.003) and FPD (P < 0.001) in challenged broilers compared to the N.C. group (d 35). Supplementing XG and 2XG reestablished the population of Lactobacillus in the cecum of challenged birds to an intermediate level between the NC and CC groups (P > 0.05). The inclusion of XG tended to increase the expression of Junctional adhesion molecule 2 (JAM2), which was not different from CC and NC groups (P > 0.05). In conclusion, the combination of xylanase and glucanase (Natugrain TS) improved the performance and modulated jejunal microbiota of broilers under mild Eimeria challenge.

Sex proportion as a covariate increases the statistical test power in growth performance based experiments using as-hatched broilers.

The availability of sexed day-old broiler chicks is becoming an issue as feather sexing is no longer possible. This has great implications for broiler researchers as the use of randomly distributed mixed-sex birds may result in a greater between-pen variation and thus less statistical power than the use of single-sex birds. The objective of this study was to evaluate the effect of including sex proportion as a covariate in an analysis of covariance (ANCOVA) on the statistical power compared to analysis of variance (ANOVA) where sex was not considered. The statistical parameters examined include mean square error (MSE), the F-statistic, model fit, model significance and observed power. A total of 4 separate experiments that used mixed-sex broilers with unequal numbers of male and female birds per pen were conducted during which performance of the birds was measured. The male % in each pen was recorded during each experiment and corrected for mortality. The performance results were analysed by ANOVA and the statistical parameters were then compared to ANCOVA where sex proportion was included as a covariate. The results showed that a set of assumptions first needed to be met to run ANCOVA. In addition, if the ANOVA results show a high level of model significance and power, then ANCOVA may not be necessary. In other circumstances where the assumptions are met and model significance and observed power are low, the inclusion of sex proportion as a covariate in the analysis will help to reduce MSE, increase the F-statistic value and improve the model significance, model fit and observed power. Therefore, it is suggested that sex proportion should be considered as a covariate in ANCOVA to improve statistical power in nutritional experiments when male and female broilers are unequally and randomly distributed in pens.

Potential of a mixture of eugenol and garlic tincture to improve performance and intestinal health in broilers under necrotic enteritis challenge.

Plant extracts (PE) are gaining increased attention as potential alternatives to in-feed antimicrobials (AM) due to their known antimicrobial activities. This study was conducted to examine the potential of PE, a microencapsulated product composed of eugenol and garlic tincture as an alternative to AM-agent on performance and intestinal health in broilers under necrotic enteritis (NE) challenge. A total of 960 day-old mixed-sex Cobb 500 chicks were randomly distributed to 48-floor pens with 6 treatments replicated 8 times with 20 birds each. The 6 treatments were as follows: UC, unchallenged control; CC, challenged control; PE, challenged group plus PE; AM, challenged group plus AM; FAP, challenged group plus a full dose of AM with PE; HAP, challenged group plus a half dose of AM with PE in starter, grower and finisher phases. Birds in the challenged groups were inoculated with Eimeria spp. on d 9 and Clostridium perfringens on d 14. The body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR), and livability of birds were compromised, and intestinal lesions and mortality were increased (P < 0.05) by NE challenge, illustrating a successful clinical NE challenge. Birds fed AM had higher BWG and FI, and lower FCR, mortality, and intestinal lesions compared to the CC group (P < 0.05). Birds fed PE had improved FCR (P < 0.05) and livability (5.8%) in an overall period compared to the CC group. On d 16, PE supplementation reduced ileal lesion scores in only male birds (P < 0.05). Birds fed PE had decreased Eimeria maxima and Eimeria acervulina oocyst counts in caecal content (P < 0.05). Birds fed PE had decreased Escherichia brunetti and total oocyst counts in caecal content, and E. acervulina oocyst counts in ileal content in only female birds (P < 0.05). On d 35, PE supplementation reduced variation of BW in both male and female birds and increased yellowness (b∗ value, 14.4%) in the thigh. These findings suggest the potential of PE supplementation in diets to improve the performance and intestinal health of birds under clinical NE as indicated by improved FCR, livability, uniformity, reduced ileal lesions, oocyst counts and increased skin yellowness. However, the protective effect of PE may not be apparent in the presence of AM in the feed.

Organic acid blends improve intestinal integrity, modulate short-chain fatty acids profiles and alter microbiota of broilers under necrotic enteritis challenge.

Controlling enteric diseases of broilers is crucial. Among many additives, organic acids (OA) and their blends are gaining attention to combat diseases in the post-antibiotic era. The current study evaluated the potentials of short-chain fatty acids (SCFA) and medium-chain fatty acids (MCFA) blends and/or phenolic compounds on intestinal integrity, intestinal pH, caecal microbiota, and caecal SCFA profiles of broilers under necrotic enteritis (NE) challenge. The additives used were: (A) a blend of SCFA, MCFA, and a phenolic compound (SMP), (B) a blend of free and buffered SCFA with MCFA (SMF), and (C) a blend of free and buffered SCFA with a high concentration of MCFA (SHM). A total of 1,404 male parental chicks of Ross 308 broilers were randomly allocated to 78 floor pens on hatching day with 6 treatments replicated 13 times with 18 birds per pen. The treatments were: UCC, unchallenged control; CHC, challenged control; BAC, challenged group plus zinc bacitracin; SMP, challenged group plus additive SMP; SMF, challenged group plus additive SMF; SHM, challenged group plus additive SHM. Birds were challenged with field-strain Eimeria spp. on d 9 and Clostridium perfringens on d 14. Birds challenged with NE increased fluorescein isothiocyanate dextran (FITC-d) concentration in serum, reduced acetate and butyrate concentrations, and increased Bacteroides and C. perfringens load in the caeca (P < 0.05). Birds fed additives decreased FITC-d from gut to serum, reduced Bacteroides (d 16, P < 0.05) and numerically reduced C. perfringens load compared to CHC group. Birds fed additive SHM had higher concentrations of acetate and butyrate (d 21, P < 0.05) than CHC group but were not different from SMP and SMF groups. All the additives exhibited similar intestinal protection against NE compared to the BAC group indicated by FITC-d concentration in serum, acetate, propionate and butyrate concentrations in the caeca, and caecal bacterial loads except for the C. perfringens (P > 0.05). The SMP group had a higher load compared to BAC (P < 0.05). These findings suggest the promising effects of OA blends as alternatives to BAC to ameliorate the impact of NE challenge of broilers as indicated by improved intestinal health.

Detection and Quantification of Clostridium perfringens and Eimeria spp. in Poultry Dust Using Real-Time PCR Under Experimental and Field Conditions.

Infection of poultry with Eimeria spp., the causative agent of coccidiosis, can predispose birds to necrotic enteritis (NE) caused by netB gene-positive strains of Clostridium perfringens. The detection of Eimeria spp., C. perfringens, and netB were examined in settled dust from broiler flocks under experimental and field conditions. Dust samples were collected from settle plates twice weekly from two experimental flocks inoculated with three species of pathogenic Eimeria in 9-day-old chicks, followed by netB gene-positive C. perfringens 5 days later to produce subclinical and clinical NE. A noninoculated flock was sampled weekly from day 0 and served as a control flock. An additional 227 dust samples from commercial broiler flocks were collected at the end-of-batch (6-7 wk of age; one scraped dust sample per flock). In the NE-subclinical and NE-clinical flocks, high levels of Eimeria spp. and C. perfringens were detected after inoculation followed by a gradual decline over time. In the control flock, C. perfringens and netB were detected at low levels. No significant effect of sampling location was evident on Eimeria spp., C. perfringens, and netB load within poultry houses. These results provide evidence that Eimeria spp., C. perfringens, and netB gene copies can be readily measured in poultry dust samples collected in settle plates and may provide an alternative sampling method for monitoring flock coccidiosis and NE status. Further studies are required to assess the utility for such a test in commercial flocks.

Artículo regular­Detección y cuantificación de Clostridium perfringens y Eimeria spp. en polvo de instalaciones avícolas mediante PCR en tiempo real bajo condiciones experimentales y de campo. La infección de aves comerciales con Eimeria spp., el agente causante de la coccidiosis, puede predisponer a las aves a enteritis necrótica (NE) causada por cepas de Clostridium perfringens positivas a la presencia del gene netB. La detección de Eimeria spp., C. perfringens y del gene netB se examinó en el polvo sedimentado de parvadas de pollos de engorde bajo condiciones experimentales y de campo. Se recolectaron muestras de polvo por sedimentación en placa dos veces por semana de dos parvadas experimentales inoculadas con tres especies de Eimeria patógena en pollitos de nueve días, seguidas de C. perfringens positiva al gene netB cinco días después para producir enteritis necrótica subclínica y clínica. Una parvada no inoculada se muestreó semanalmente desde el día cero y sirvió como parvada control. Se recolectaron 227 muestras adicionales de polvo de parvadas de pollos de engorde comerciales al final del lote (6 a 7 semanas de edad; una muestra de polvo por raspado por parvada). En las parvadas con enteritis necrótica subclínica y clínica, se detectaron niveles altos de Eimeria spp. y de C. perfringens después de la inoculación seguida de una disminución gradual con el tiempo. En la parvada control, C. perfringens y el gene netB se detectaron en niveles bajos. No fue evidente ningún efecto significativo de la ubicación del muestreo sobre la carga de Eimeria spp., C. perfringens y del gene netB dentro de las casetas. Estos resultados proporcionan evidencia de que las copias genéticas de Eimeria spp., C. perfringens y del gene y netB se pueden medir fácilmente en muestras de polvo de instalaciones avícolas recolectadas mediante sedimentación en placa y pueden proporcionar un método de muestreo alternativo para monitorear coccidiosis y el estado de enteritis necrótica en la parvada. Se requieren más estudios para evaluar la utilidad de tal prueba en parvadas comerciales.

A Microencapsulated Mixture of Eugenol and Garlic Tincture Supplementation Mitigates the Effect of Necrotic Enteritis on Intestinal Integrity and Increases Goblet Cells in Broilers.

This study was conducted to examine the effects of a plant extract mixture, a microencapsulated product composed of eugenol and garlic tincture (PE), on intestinal health in broilers under necrotic enteritis (NE) challenge. A total of 960 d-old mixed-sex Cobb 500 chicks were randomly distributed to 48-floor pens housing 20 birds per pen. Six treatments were applied: UC, unchallenged control; CC, challenged control; PE, challenged group plus PE; AM, challenged group plus antimicrobial (AM); FAP, challenged group plus a full dose of AM with PE; HAP, challenged group plus a half dose of AM with PE in starter, grower and finisher phases. Birds in the challenged groups were inoculated with Eimeria spp. on d 9 and Clostridiumperfringens on d 14. On d 16, the CC group had increased serum fluorescein isothiocyanate dextran (FITC-d), reduced villus surface area, goblet cell number, upregulated CLDN1, JAM2 genes and reduced microbial diversity compared to the UC group (p < 0.05). Birds fed PE had reduced FITC-d, increased goblet cell number and Bifidobacterium compared to the CC group (p < 0.05). Birds fed PE had reduced CLDN5 expression in male birds, and Bacteroides spp. in female birds than CC group (p < 0.05). These findings suggest that PE supplementation mitigates the effect of NE by improving the intestinal health of birds.

Potential of blended organic acids to improve performance and health of broilers infected with necrotic enteritis.

Organic acids (OA) and their blends have been shown to positively affect performance and health of broilers. However, the data in the literature are not consistent. This study examined the potential of blended short-chain fatty acids (SCFA) with medium-chain fatty acids (MCFA) as alternatives to antibiotic growth promoters (AGP) on performance, health and welfare of broilers infected with necrotic enteritis (NE). The additives used were: A) a blend of SCFA, MCFA, and a phenolic compound (SMP); B) a blend of free and buffered SCFA with MCFA (SMF); C) a blend of free and buffered SCFA with a high concentration of MCFA (SHM). A total of 1,404 Ross 308 one-day-old male parental chicks were randomly distributed into 78-floor pens with 13 replicates of 18 birds each. Six treatments were the following: T1, unchallenged control (UCC); T2, challenged control (CHC); T3, challenged group plus zinc bacitracin (BAC); T4, challenged group plus additive SMP; T5, challenged group plus additive SMF; T6, challenged group plus additive SHM. Challenged birds were gavaged with Eimeria spp. on d 9 and Clostridium perfringens EHE-NE18 on d 14. Post NE challenge and cumulatively, BWG, FCR, and nutrient digestibility of birds were compromised (P < 0.05) by NE challenge indicating a successful induction of sub-clinical NE. Additive SHM had higher BWG compared to CHC and BAC groups (P = 0.001; d 10 to 24) but not different from SMP and SMF groups (P > 0.05). All the 3 additive groups had lower FCR compared to CHC (P = 0.001; d 0 to 35), and exhibited similar jejunal lesions (d 16) compared to BAC and apparent ileal protein digestibility (d 21) compared to UCC and BAC groups (P > 0.05). Birds in additive SHM group had a higher concentration of serum IgA compared to all groups (P = 0.001) except additive SMF (P > 0.05; d 21). All the additive groups had lower footpad dermatitis and hock burns compared to CHC (P < 0.05). The findings suggest the potential of blended OA as alternatives to BAC to protect broilers from NE indicated by improved FCR, immunity, digestibility, and bird welfare.

Monoglyceride Blend Reduces Mortality, Improves Nutrient Digestibility, and Intestinal Health in Broilers Subjected to Clinical Necrotic Enteritis Challenge.

This study evaluated the potential of monoglyceride blend (MG) and buffered formic acid (FA) as alternatives to antibiotics in the performance and intestinal health of broilers under clinical necrotic enteritis (NE) challenge. A total of 544 as-hatched Ross 308 broiler chicks were randomly distributed to 32-floor pens housing 17 birds per pen. The four treatments were: NC-non-additive control; ZBS-antibiotic group supplemented with zinc bacitracin and salinomycin; MG-additive MG supplementation in the starter phase only; and MGFA-additive MG in starter phase and FA in grower and finisher phases. All birds were challenged with Eimeria spp. and Clostridium perfringens. Results showed that the NC group had lower BWG and higher FCR than the ZBS group in the grower and overall period (p < 0.05). The NC group had higher NE-caused mortality (days 14 to 17) than the ZBS group (p < 0.05). Birds fed MG had lower NE-caused mortality than the NC group (p < 0.05). Birds fed MG had upregulated jejunal tight junction protein1 (TJP1) and immunoglobulin (IgG) on day 16 and improved gross energy digestibility on day 24 than the NC group (p < 0.05). These findings suggest that supplementation of MG may improve intestinal health and protect birds from clinical NE occurrence.

Nano-sized Zinc in Broiler Chickens: Effects on Growth Performance, Zinc Concentration in Organs, and Intestinal Morphology.

The effects of dietary supplementation of zinc (Zn) sources and concentrations were investigated on growth performance, absorption into tissues, fecal excretion, nutrient retention, and intestinal morphology in broilers fed a corn-soybean meal basal diet. A total of 525 one-day-old chicks (Ross 308) were assigned based on body weight to seven dietary treatments. There were five replicate pens for each treatment and 15 broilers per replicate pen. The dietary treatments included a basal diet (control, without supplementing Zn), and basal diet supplemented with Zn, as inorganic zinc sulfate (ZnS; 110 mg/kg); organic Zn-methionine (ZnM; 110 mg/kg); hot-melt extruded (HME) 25 zinc sulfate (27.5 mg/kg); HME50 zinc sulfate (55 mg/kg); HME75 zinc sulfate (82.5 mg/kg); or HME100 zinc sulfate (110 mg/kg) for 35 days in two phases (d 1-21, phase I and d 22-35, phase II). Bodyweight and feed efficiency of broiler chicks fed diets supplemented with increasing dietary concentrations of HME-Zn improved linearly during the study period (P<0.05). Compared to the control treatment, the ZnS, ZnM, and HME diets increased Zn concentrations in the serum and liver. Inorganic ZnS supply resulted in the highest Zn concentration in excreta. Increasing supplemented Zn content in diets as HME linearly increased Zn concentration in the excreta, serum, liver, and tibia. Broiler chicks fed diets supplemented with increasing concentrations of HME increased villus height (VH; linear and quadratic) of the jejunum and VH of the ileum (linear). Increasing concentrations of dietary Zn supplied as HME resulted in linearly enhanced dry matter, gross energy, and nitrogen retention of broilers on day 21. These results suggest that dietary HME-Zn at a lower level (55 ppm) shows the same growth performance as common ZnSO4 at 110 ppm.

Dietary supplementation of Neem (Azadirachta indica) leaf extracts improved growth performance and reduced production cost in broilers.

BACKGROUND AND AIM: Global trend to remove the antibiotic growth promoter (AGP) from animals contributes to the exploration of successful measures to sustain production and reduces the intestinal diseases in the post-AGP era. Plant extracts, therefore, have been used to improve performance and intestinal health. Here, we conducted a study to evaluate the effects of neem (Azadirachta indica) leaf extracts (NLE) as alternatives to AGPs in broiler chickens. MATERIALS AND METHODS: Sixty day-old broiler chicks were assigned to 12-floor pens, each stocked with five birds and divided into three treatment groups of four pens per treatment. The groups were: Negative control, basal diet without additives; positive control, basal diet with antibiotics and vitamins; and NLE treated group, basal diet supplemented with 0.1% aqua extract of neem leaves. RESULTS: Overall feed intake was significantly (p≤0.05) highest in the positive control. Higher body weight, higher dressing percentage, and lower feed conversion ratio were observed in birds treated with NLE compared to the negative control group (p≤0.05) but not the positive control group (p>0.05). There was no significant variation in hematology between different groups. Furthermore, the economic evaluation indicated that the NLE treatment was found cheaper than control and antibiotic treatment in cost-benefit analysis. CONCLUSION: We suggest NLE might be a cheaper alternative to antibiotics in broiler production as indicated by improved body weight and feed efficiency.

Investigating Meat Quality of Broiler Chickens Fed on Heat Processed Diets Containing Corn Distillers Dried Grains with Solubles.

The present study investigated the effects of feed form and distiller's dried grain with solubles (DDGS) on meat quality and fatty acids profile of broiler chickens. A total of 720 broilers (Ross 308; average BW [body weight] 541±5.7 g) were randomly allotted to six treatments. Birds were fed three different feed forms (mash; SP, simple pellet; EP, expanded pellet) and DDGS (0 or 200 g kg-1) in a 3×2 factorial arrangement. The addition of DDGS and EP to the diet resulted in increased shear force of breast meat. Moreover, DDGS inclusion in the diet reduced the concentration of stearic acid and behenic acid in thigh meat. Pelleting (SP and EP) of the diets increased palmitic acid content in the thigh, whereas the linolenic acid content decreased. The breast mass was higher with EP and SP diets than with the mash diet. Feed processing led to increased pectoralis muscle and drum mass compared to mash-fed chickens. In conclusion, our results demonstrated that EP decreased thigh linolenic acid and meat shear force. In addition, DDGS supplementation in broiler hampers meat quality by increasing the shear force.

Evaluation of high nutrient diets on litter performance of heat-stressed lactating sows.

OBJECTIVE: The present study investigated the litter performance of multiparous sows fed 3% and 6% densified diets at farrowing to weaning during summer with mean maximum room temperature of 30.5°C. METHODS: A total of 60 crossbred multiparous sows were allotted to one of three treatments based on body weight according to a completely randomized design. Three different nutrient levels based on NRC were applied as standard diet (ST; metabolizable energy, 3,300 kcal/kg), high nutrient level 1 (HE1; ST+3% higher energy and 16.59% protein) and high nutrient level 2 (HE2; ST+6% higher energy and 17.04% protein). RESULTS: There was no variation in the body weight change. However, backfat thickness change tended to reduce in HE1 in comparison to ST treatment. Dietary treatments had no effects on feed intake, daily energy intake and weaning-to-estrus interval in lactating sows. Litter size, litter weight at weaning and average daily gain of piglets were significantly greater in sows in HE1 compared with ST, however, no difference was observed between HE2 and ST. Increasing the nutrient levels had no effects on the blood urea nitrogen, glucose, triglyceride, and creatinine at post-farrowing and weaning time. The concentration of follicle stimulating hormone, cortisol and insulin were not affected by dietary treatments either in post-farrowing or weaning time. The concentration of blood luteinizing hormone of sows in ST treatment was numerically less than sows in HE2 treatment at weaning. Milk and colostrum compositions such as protein, fat and lactose were not affected by the treatments. CONCLUSION: An energy level of 3,400 kcal/kg (14.23 MJ/kg) with 166 g/kg crude protein is suggested as the optimal level of dietary nutrients for heat stressed lactating sows with significant beneficial effects on litter size.