Raising backyard chickens is an ever-growing hobby in the United States. These flocks can be a substrate for respiratory disease amplification and transmission to commercial facilities. Five hundred fifty-four chickens from 41 backyard flocks were sampled in this study. ELISA kits were used to detect antibodies against avian influenza (AI), infectious laryngotracheitis (ILT), Newcastle disease (ND), infectious bronchitis (IB), Ornithobacterium rhinotracheale (ORT), Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS). All visited flock owners answered a biosecurity questionnaire that assessed biosecurity measures. The questionnaire revealed that backyard poultry owners lack simple biosecurity measures such as use of dedicated shoes, their chicken sources are unreliable, and few of them benefit from veterinary oversight. Only one flock had a clear vaccination history against ND and IB. ORT, ND, IB, MS, MG, and ILT were the most seroprevalent in backyard poultry flocks with 97% (41/42), 77.5% (31/40), 75% (30/40), 73% (31/42), 69% (29/42), and 45% (19/42), respectively. The vaccinated flock was not considered in these calculations. When examining the distance between backyard flocks and the nearest commercial poultry facility, ND and MG were significantly more likely to be found in backyard flocks close to (<4 miles) whereas ORT was significantly more likely in backyard chickens located far from (>4 miles) commercial poultry. Birds purchased directly from National Poultry Improvement Plan hatcheries showed a reduced ND, MG, and MS antibody prevalence. Wearing dedicated shoes decreased MS antibody-positive birds. Finally, history of wild bird contact had a clear effect on an increased seroprevalence of NDV and MG. Serological results suggest that backyard poultry flocks have the potential to serve as a reservoir or amplifier for poultry respiratory diseases. The information generated in this project should direct extension efforts toward emphasizing the importance of small flock biosecurity and chick acquisition sources.

This study was to create an ω-3 (n-3) fatty-acid-enriched chicken product using defatted green microalgae (DGA, Nannochloropsis oceanica) biomass out of biofuel research. Hatching Ross broiler chicks were fed a corn-soybean meal diet containing 0 (control), 2, 4, 8, or 16% DGA for 6 weeks (n = 6 cages/diet). The DGA inclusion resulted in a linear (p < 0.001) increase in total n-3 fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) in plasma, liver, breast, and thigh at weeks 3 and 6. The increase in the breast EPA + DHA by the 16% DGA diet reached 60-fold (p < 0.0001) over the control. The 8 and 4% DGA diets elevated (p < 0.05) liver mRNA levels of Δ-9 (88%) and Δ-6 (96) desaturases. In conclusion, 8-16% of the DGA can be added in diets for broilers to produce a n-3 fatty-acid-enriched chicken meat.

Background The potential for dietary microalgae to enrich eggs of laying hens with ω-3 (n–3) fatty acids, and the mechanisms involved, are unclear. Objectives The aim of this study was to determine the effects and molecular regulation of a defatted Nannochloropsis oceanica microalgae (DNOM) biomass on the enrichment of the eggs and tissues of laying hens with ω-3 fatty acids. Methods Fifty Shaver-White Leghorn hens (46 wk of age, body weight: 1.70 ± 0.27 kg) were individually caged (n = 10) and fed a corn-soy–based diet supplemented with DNOM at 0% (control), 2.86%, 5.75%, 11.5%, and 23% for 6 wk. Fatty acid profiles, health status, and related gene expression in eggs, blood, and tissues were performed at weeks 0, 2, 4, and 6. Data were analyzed by a combination of 1-factor ANOVA and correlation between DNOM doses and measures. Results The DNOM produced linear (P &lt; 0.01) enrichments of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and total ω-3 fatty acids in the egg yolk (R2 &gt; 0.9) and of DHA in the liver, breast, and thigh (R2 = 0.66–0.82). Concentrations of EPA + DHA in the egg yolk and these 3 tissues of hens fed 11.5% and 23% DNOM were 1.4–2.1, 0.6–1, 3.3–5.3, and 6–7 times greater (P &lt; 0.001) than those in the controls, respectively. The DNOM caused dose-dependent elevations (P &lt; 0.01) of malic enzyme and elongases 3, 4, and 5 mRNA levels (R2 = 0.97, 0.78, 0.97, and 0.86, respectively), along with increased (P &lt; 0.01) Δ5- and Δ6-desaturases and decreased (P &lt; 0.01) Δ9-desaturase and acyl-coenzyme A thioesterase 4 mRNA levels in the liver. Conclusions Feeding DNOM to laying hens produced dose-dependent enrichments of DHA in their eggs, liver, and muscles by regulating key genes involved in the elongation and desaturation of polyunsaturated fatty acids. Our findings will help produce DHA-enriched eggs.

No abstract

No abstract