Journal of Applied Poultry Research最新文献

The aim of the current study was to evaluate the influence of stressors on histomoniasis development and lateral transmission of Histomonas meleagridis. In the following experiments, half of the birds in each pen were inoculated with H. meleagridis to study disease transmission and progression. Birds were infected at 5 wk of age (experiments 1 and 3) or at 2 wk of age (experiment 2). Disease progression was evaluated by infection rate, mortality rate, and pathologic lesions in the ceca and liver. Reported results were applicable for directly infected birds as lateral transmission was not induced in these experiments. In experiment 1, the results showed high electrolyte, low-density diet (HE + LD), feed withdrawal (FW), caused higher infection rates and increase lesion scores in the liver and ceca compared to con. Experiment 2 further investigated the influence of low-density diet (LD) in conjunction with coccidiosis (LD + C) or feed withdrawal (LD + FW). All treatments had higher infection rates, mortality rates, ceca and liver scores compared to PC. In experiment 3, birds were fed diets containing naturally occurring aflatoxin at 0 ppb (AFLB1), 6.26 ppb (AFLB1 Low), or 19.82 ppb (AFLB1 High). No significant differences among treatments were observed. Though lateral transmission was not induced by theses stressors, the results of these experiments demonstrated that low-density diets, feed withdrawal and/or coccidial infection facilitated more severe histomoniasis infection.

Ensuring good water quality is one of the key management strategies to promote optimal broiler health and performance. A few studies have assessed the microbial status of drinking water for poultry, but there is insufficient information on biofilm in the drinking water lines within the poultry housing facilities. The buildup of microbes in the drinking water system could potentially result in biofilm formation which eventually deteriorates water quality. Hence, in this preliminary study, we sought to evaluate biofilm formation in the drinking water lines of selected broiler houses and characterize their microbial composition. Three random houses in each of 5 farms were visited representing 15 total houses used in this study. Using a borescope, we confirmed the presence of biofilm in 4 water lines per house on each farm, and a sterile gauze swab was used to collect the biofilm from these water lines. All biofilm samples were analyzed for the total aerobic plate count (APC), presence of yeasts and molds (YM), and Enterobacteriaceae (EB). The data were analyzed with ANOVA, and means were separated with Tukey's HSD test at P ≤ 0.05 using JMP software. All 15 houses evaluated had aerobic bacteria population and YM, whereas 7 out of the 15 houses had EB counts. For APC, there were significant differences across the farms (P < 0.0001) with Farm 1 having the highest APC (3.65 Log₁₀ CFU/mL) and Farm 5 having the lowest APC (2.05 Log₁₀ CFU/mL). For YM, significant differences existed across farms (P < 0.0001), Farm 2 had the highest counts (4.44 Log₁₀ CFU/mL), whereas Farm 5 had the lowest count (1.19 Log₁₀ CFU/mL). EB was detected in 3 out of the 5 farms and the counts were not statistically different (P = 0.07). Based on a sample size of 15 commercial broiler houses, these results suggest the need to evaluate water lines for biofilm and develop effective mitigations.

Feeding breeder hens diets enriched with omega-3 fatty acids (n-3 FA) has previously been shown to increase their progeny's immunocompetence. During an experiment to assess the effects of maternal-fed n-3 FA on broiler behavior, broiler chickens experienced an unexpected disease outbreak. Here, we present the broiler offspring's body weight, uniformity, and feed intake data. Broiler breeders were fed diets with or without flaxseed (n-3 FA source) in the rearing or laying period. Two cohorts of broiler offspring were hatched and placed in 24 mixed-sex pens per cohort. Broiler offspring were weighed weekly, and uniformity (CV%) was calculated by sex on a pen level. Cumulative feed intake was recorded, and feed conversion ratio (FCR) was estimated per pen. Cohort 1 was diagnosed with infectious bronchitis at 2 wk, and Cohort 2 at 5 d of age and was further diagnosed with avian reovirus. Broiler offspring weighed 41% less than the target weight at 6 wk of age. Flaxseed fed to breeders during the laying period resulted in lighter offspring weight at 6 wk of age (z = 3.98, P < 0.001). Uniformity was not affected by maternal diet (χ² = 6.51, P = 0.26). Maternal rearing diet (F = 3.35, P = 0.07), but not laying diet (F = 0.65, P = 0.42) nor their interaction (F = 2.34, P = 0.13) affected feed intake. Flaxseed rearing (F = 4.54, P = 0.04) and laying (F = 6.24, P = 0.02) diets increased offspring FCR, broilers from broiler breeders fed flaxseed throughout had the poorest feed conversion (P < 0.03). The study showed that maternal-fed flaxseed diets did not modulate the impact of disease on the growth performance of broiler chickens.

The presence of pathogens, e.g., Escherichia coli (E. coli), in chicken manure can potentially lead to serious infections and foodborne diseases when spread on land as organic fertilizer. Therefore, it is essential to inactivate these bacteria before land application. The aim of the present study was to determine the survival of E. coli and the temperature development in compost piles during composting of chicken manure with a typically low carbon/nitrogen (C/N) ratio and moisture content (MC). In a summer and winter trial, chicken manure piles were stacked in 1) uncovered static piles, 2) covered static piles, and 3) periodically turned piles. Samples were inoculated with a nonpathogenic E. coli strain at levels of 10⁷ cfu/g and placed at subsurface and center locations of the piles. Within 24 h, E. coli were undetectable by direct count in all piles and at all sample locations. By d 28, all samples were also negative for E. coli by enrichment. Despite the suboptimal composting conditions with an initial C/N ratio of 10:1 and an MC below 40%, temperatures within all piles mainly exceeded 50°C within the first 24 h. Statistical analyses showed that the sample location and the total hours at temperatures ≥50 and 55°C in the piles had significant influences on the survival of E. coli in the chicken manure compost. The season and manure treatment method had no significant effects on the presence of E. coli.

In addition to the whole white-flowered pea, pea protein concentrates and pea hulls can be utilized in animal nutrition. In particular, fermentable carbohydrates and fibers in peas and pea products seem to contribute to intestinal health and health maintenance in poultry, due to their prebiotic effect on the intestinal microbiota. This study was conducted to investigate the effect of different proportions of peas (P), pea protein concentrate (PPC) and pea hulls (PH) in complete feed mixtures for broilers on growth and slaughter performance as well as intestinal microbiota. Twenty diets with varying proportions of peas and pea products were fed to male broilers from d 1 to 34. Short-chain fatty acid analysis and 16S sequencing were used to examine the ileal and cecal microbiota for selected feeding groups. Overall, the attained fattening performances were at a high level. The use of peas and pea products did not affect body weight on d 34 or slaughter performance. The use of pea hulls up to 6% resulted in the highest overall feed intake and overall feed conversion ratio (P < 0.001). Microbiota composition and ileal bacterial metabolites were unchanged. Microbiota changes in the cecum were found between dietary treatments for several subdominant microbial genera that preferentially ferment carbohydrates. This study has shown that peas and pea products are well-suited as feedstuffs for feeding broilers when used appropriately. Furthermore, the intestinal microbiota responded with an increased abundance of nonpathogenic genera that may help maintain intestinal microbial homeostasis.

Recommendations for the optimal stocking density (SD) of chicks within transport boxes have not previously been published, with current recommendations lacking scientific support. As a result of concerns from welfare organizations regarding high SD in delivery boxes, a field trial was conducted at a commercial hatchery to understand SD effects on chick stress and box microclimate. Lohmann LSL-Lite chicks (n = 3,630) were placed in plastic transport boxes (58 × 46 cm) for a 7-h simulated transport period (uncontrolled humidity; 27°C). The SD treatments (trt) used were 80, 100, or 120 chicks/box (33.4, 26.7, or 22.2 cm²/chick). Group body weight (BW); vent temperature; concentrations of corticosterone, electrolytes, and glucose; and yolk sac weights were measured pre- and post-trt. Temperature and relative humidity (RH) were recorded every 5 min in the boxes. Thermal images of the boxes were taken every h for box floor and chick surface temperature and to calculate spatial area used per chick. Body weight, vent temperature, yolk sac weights, and corticosterone concentration did not differ between SD trt post-trt. Box temperature and RH increased with increasing SD. Thermal images showed the minimum temperature was lowest, and temperature variability was greatest, in the 80 trt compared to the 100 and 120 trts. The spatial area used per chick differed between trt and chicks occupied less than the total spatial area available in all trt. In conclusion, within the conditions used in this study, altering SD did not affect bird wellbeing, but reducing the density increased temperature variability within the boxes.

The chicken gut microbiota plays important roles in host physiology and well-being. It can be impacted by several management and environmental factors like the use of antibiotic growth promoters (AGP) and heat stress (HS). Probiotics, essential oils (EO), and vitamins (such as folic acid) are bioactive substances that could potentially modulate the gut microbiota and promote its resilience to stressful environmental factors, especially when supplied as early as during embryonic development. This study evaluated the gut microbiota modulating potential of in ovo delivered probiotics, folic acid (FA), and in ovo + in-water delivered EO in broiler chickens, as compared to an in-feed AGP, under an HS challenge. Results from this study indicate that HS, AGP, and in ovo + in-water EO treatments modified chicken ceca bacterial populations and suggest that the microbiota-mediated role of AGP in growth promotion is related to improved biosynthesis of essential nutrients (amino acids and vitamins especially) and utilization of carbon sources derived from host diet and microbiome.

On-farm nutrient segregation is influenced by manufacturing techniques, pellet-to-fine ratio (P:F), and feed line length. Additional research to understand nutrient segregation over time is warranted. Therefore, a study was conducted to determine how feed and nutrients travel throughout a commercial poultry house over a 5-d period. High P:F feed (85:15) was fed to commercial turkeys as part of a standard grow-out. Two experiments were conducted concurrently, differing in feed sample collection techniques. Samples were collected from 5 feed pan locations (FPL), designated at every 15 m of the 75 m feed lines. In experiment 1, residual feed was collected for analysis. In experiment 2, different feed pans were emptied of residual feed and then filled before collection. Measured variables included P:F, near-infrared spectrophotometer (NIRS) predicted nutrients, gross energy, phytase activity, amino acids (AA), and mineral concentrations. Data were analyzed in a repeated measure ANOVA using PROC MIXED in SAS. In experiment 1, residual feed consisted mostly of fines (∼73%), and nutrient composition of the feed was similar on each day (P > 0.05). In experiment 2, P:F and Cu concentration varied day by day (P < 0.001), owing to feed flow dynamics in the feed bin. Only proline varied by FPL (P = 0.050). Neither day of sample collection nor FPL affected crude protein, crude fiber, ash, gross energy, and phytase activity of the feed (P > 0.05). Overall, these data support augering high P:F feed through short feed lines for an even distribution of nutrients throughout the house.

The aim of this study was to investigate the effects of early dextrose (Dex) feeding on subsequent growth performance of broilers. A total of 700 male day-old broiler chicks were randomly allocated into 50 floor pens (in a balanced completely randomized design with 2 treatments) receiving either a control corn–soybean meal-based diet (control treatment) or a diet in which corn was partially (5%) replaced by Dex Monohydrate (Dex treatment). The performance data were recorded at 7, 20, 30, 40 d. Samples of the birds were slaughtered at 7, and 40 d of age, and their carcass, serum, and intestinal morphology traits were analyzed. The results showed that early feeding of the Dex resulted in significant improvement in weight gain (WG) during d 1 to 7 (P < 0.01), 21-30 (P < 0.05), and 1-40 (P < 0.01), as well as the carcass traits at d 40 (P < 0.05). Feeding Dex increased serum glucose, total protein, globulin, triiodothyronine (T3), and T₃/T₄ ratio (P < 0.05). Duodenal villi height, crypt depth, and villus to crypt ratio (V/C) were affected (P < 0.05) by early Dex feeding. In conclusion, early feeding of a highly available carbohydrate source (Dex) improves subsequent growth performance and carcass traits of broilers.

Citrus sinensis (sweet orange) seeds are sources of significant quantities of bioactive compounds and dietary fiber which have shown a range of biological activities in humans but are essentially discarded with abundant waste production. The aim of this study was to evaluate the impact of C. sinensis seed powder on the morphological and histological development of the small intestine of broiler chickens. A total of 480-day-old Cobb 500 broilers chicks were divided into 4 groups with 6 replicates and 20 chicks per pen, namely control (T): fed only standard diet; CSS-0.25: standard diet + 0.25% C. sinensis seed powder; CSS-0.50: standard diet + 0.5% C. sinensis seed powder and CSS-0.75: standard diet + 0.75% C. sinensis seed powder over 42 d in a completely randomized design. The results indicated that a diet containing 0.75% of C. sinensis seed powder significantly (P < 0.05) increased the weight and length of the small intestine and its 3 segments. Furthermore, villi height, villi/crypt ratio, and crypt depth in the jejunal and ileal sections of the intestine increased significantly (P < 0.05) with 0.5% and 0.75% C. sinensis seed powder supplementation. In addition, weight gain and feed conversion ratio were significantly affected in the 0.5 and 0.75% groups on d 21 and 42. In conclusion, supplementation with 0.5 and 0.75% C. sinensis seed powder improves intestinal development and intestinal health in chickens.