When laying hen diets are enriched with omega-3 polyunsaturated fatty acids to generate value-added eggs for human consumption markets, concentrations of alpha-linolenic (ALA), eicosapentaenoic (EPA), and docosahexaenoic acids (DHA) in the yolk can reach 250 mg/50 g whole egg. Flaxseed, a rich source of ALA, is commonly used for omega-3 enrichment; however, the impact of dietary flaxseed source (extracted oil vs. milled seed) on fatty acid transfer to egg yolk in laying hens is unknown. Therefore, transfer of ALA, EPA, and DHA into egg yolk from extracted flaxseed oil or milled flaxseed was evaluated in Hy-Line W-36 laying hens over an 8-week feeding period (25 to 33 wk old). Hens (n = 132) were randomly housed with 3 birds/cage (4 replicates/treatment) for each of the 11 treatment groups. Diets were isocaloric and consisted of a control diet, 5 flaxseed oil diets (0.5, 1.0, 2.0, 3.0, or 5.0% flaxseed oil), and 5 milled flaxseed diets (calculated flaxseed oil concentration from milled flaxseed 0.5, 1.0, 2.0, 3.0, 5.0%). Increasing dietary concentrations of flaxseed oil and milled flaxseed resulted in increased ALA, EPA, and DHA concentration in egg yolk, and fatty acid deposition from flaxseed oil was 2 times greater compared to milled flaxseed when fed at the same dietary inclusions (P < 0.01). Egg yolk EPA and DHA concentrations were not different due to oil or milled source (P = 0.21); however, increasing dietary inclusion rates of flaxseed oil from either source increased yolk EPA and DHA (P < 0.01). Hens fed either flaxseed oil or milled flaxseed resulted in reduced BW change as dietary concentrations increased (P = 0.02). Feed efficiency increased as flaxseed oil increased in concentration, while feeding milled flaxseed decreased feed efficiency (P = 0.01). Analysis of the nitrogen corrected apparent metabolizable energy of flaxseed oil resulted in 7,488 kcal/kg on an as-fed basis. Dietary flaxseed oil improved feed efficiency and increased ALA deposition into yolk compared to a milled source, demonstrating flaxseed oil to be a viable alternative for ALA egg enrichment.

Venous blood gas and chemistry reference ranges were determined for commercial Hy-Line W-36 pullets and laying hens utilizing the portable i-STAT®1 analyzer and CG8+ cartridges. A total of 632 samples were analyzed from birds between 4 and 110 wk of age. Reference ranges were established for pullets (4 to 15 wk), first cycle laying hens (20 to 68 wk), and second cycle (post molt) laying hens (70 to 110 wk) for the following traits: sodium (Na mmol/L), potassium (K mmol/L), ionized calcium (iCa mmol/L), glucose (Glu mg/dl), hematocrit (Hct% Packed Cell Volume [PCV]), pH, partial pressure carbon dioxide (PCO2 mm Hg), partial pressure oxygen (PO2 mm Hg), total concentration carbon dioxide (TCO2 mmol/L), bicarbonate (HCO3 mmol/L), base excess (BE mmol/L), oxygen saturation (sO2%), and hemoglobin (Hb g/dl). Data were analyzed using ANOVA to investigate the effect of production status as categorized by bird age. Trait relationships were evaluated by linear correlation and their spectral decomposition. All traits differed significantly among pullets and mature laying hens in both first and second lay cycles. Levels for K, iCa, Hct, pH, TCO2, HCO3, BE, sO2, and Hb differed significantly between first cycle and second cycle laying hens. Many venous blood gas and chemistry parameters were significantly correlated. The first 3 eigenvalues explained ∼2/3 of total variation. The first 2 principal components (PC) explained 51% of the total variation and indicated acid-balance and relationship between blood O2 and CO2. The third PC explained 16% of variation and seems to be related to blood iCa. Establishing reference ranges for pullet and laying hen blood gas and chemistry with the i-STAT®1 handheld unit provides a mechanism to further investigate pullet and layer physiology, evaluate metabolic disturbances, and may potentially serve as a means to select breeder candidates with optimal blood gas or chemistry levels on-farm.

There is a trend to use more alternative lipids in poultry diets, either through animal-vegetable blends, distillers corn oil, or yellow grease. This has resulted in the use of lipids in poultry diets with a higher concentration of unsaturated fatty acids, which have a greater potential for peroxidation. The objective of this experiment was to determine the effects of peroxidized corn oil on broiler performance, dietary AMEn, and abdominal fat pad weight. The same refined corn oil sample was divided into 3 subsamples, 2 of which were exposed to different peroxidative processes. The 3 diets contained the unperoxidized corn oil (UO), a slowly peroxidized corn oil (SO; heated for 72 h at 95°C with compressed air flow rate of 12 L/min), or a rapidly peroxidized corn oil (RO; heated for 12 h at 185°C with compressed air flow rate of 12 L/min). Diets were fed from 0 to 14 d of age with each lipid fed at a 5% inclusion rate, continuing on from 15 to 27 d of age with each lipid fed at a 10% inclusion rate. There were 6 Ross 708 broiler chicks per cage with 10 replicates for each of the 3 dietary treatments. Abdominal fat pad and excreta collection was performed on d 27. Body weight gain, feed intake and feed efficiency were measured for the 0 to 14 and 0 to 27 d periods. The increased level of peroxidation reduced AMEn in broiler diets (UO = 3,490 kcal/kg; SO = 3,402 kcal/kg; RO = 3,344 kcal/kg on an as-is basis; SEM = 12.9, P ≤ 0.01). No significant treatment differences were observed among oil supplemented birds for BW gain, feed intake, feed efficiency, or abdominal fat pad weight. In conclusion, corn oil peroxidation status resulted in a decrease in dietary AMEn, but had minimal effects on broiler performance or fat pad weights.

and Implications The extraction of corn oil from DDGS has led to an increase in the utilization of coil oil in poultry diets. This corn oil has the opportunity to undergo peroxidation during storage or processing. Therefore it is important to understand the effects of peroxidation of corn oil on growth and performance of broiler chicks. Broiler chicks were provided corn-soybean based diets containing unperoxidized corn oil (UPO), slowly peroxidized corn oil (SO; heated for 72 h at 95ᵒC), and rapidly peroxidized corn oil (RO; heated for 7 h at 185ᵒC). Corn oil was added at a 5% inclusion 0-14 d and 10% inclusion 15-27 d. A fourth treatment consisted of a supplemental oil-free diet to be used to determine the apparent metabolizable energy nitrogen corrected (AMEn) of each corn oil diet. As expected the diets without supplemental oil resulted in reduced performance, but no significant differences were observed among oil-supplemented birds for body weight gain, feed intake, or feed conversion ratio (FCR). There was a significant difference in abdominal fat pad (AFP) weights of the broilers fed RO corn oil compared to the birds fed UPO corn oil. Analysis of samples for AMEn content is underway and will be reported shortly. Corn oil peroxidation status had minimal effects on broiler performance, but did result in differences in energy utilization as indicated by AFP weight.

and Implications The objective of this experiment was to investigate how different dietary ω-3 sources affect lameness and bone integrity of commercial broiler chickens from hatching to finishing. One hundred and twenty male Ross 308 broiler chicks were assigned to three dietary treatments; control, flaxseed oil and fish oil for 4 consecutive weeks. From week 1 to 4, broilers were visually assigned a lameness score (2 non-lame to 5 non-ambulatory) and a bone integrity score (score 2 normal bones to 5 bird was non-ambulatory and was removed from the trial). There were no observed differences for the dietary treatment and week interaction for lameness or bone integrity (P = 1.00). There was no observed lameness or bone integrity differences (P ≥ 0.93) between dietary treatments. There were no observed differences for lameness (P = 0.92) and bone integrity differences (P = 1.00) over the four consecutive weeks. In conclusion, regardless of dietary treatment, birds in this study were not lame and had normal bone integrity.

and Implications The objective of this experiment was to investigate how different dietary omega-3 sources affect commercial broiler behavior from hatch to market weight. One hundred and twenty male 308 Ross broiler chicks were enrolled into the study. Three dietary treatments were compared; Control, Flaxseed-and Fish-oil. Fifteen pens were randomly selected and one focal-bird was watched continually for three periods of time. One behavior, two postures, and an unknown category were collected. Week by dietary treatment interaction was not significant for any broiler behaviors (P ≥ 0.49). There was no dietary treatment effect observed for any broiler behaviors (P ≥ 0.32). There was no observed difference for percentage of time spent at the feeder between week 1 and 4 (P = 0.14). However, there was a difference for percentage of time spent active (P < 0.0001), inactive (P = 0.0004) and unknown (P = 0.01) between week 1 and 4. Within the context of this work, the selected omega-3 dietary sources did not affect broiler behavior between weeks 1 and 4. Independent of dietary treatment, broilers increased the percentage of time spent inactive by week 4 of the study.