Impact of feeding n-3 fatty acids to layer breeders and their offspring on concentration of antibody titres against infectious bronchitis, and Newcastle diseases and plasma fatty acids in the offspring.

1. The impact of feeding sources of n-3 fatty acids (FA) to ISA Brown and Shaver White breeders and their offspring on antibody titres and plasma FA profile was examined.2. Breeders were fed either a control diet (CON); CON + 1% microalgae (DMA: Aurantiochytrium limacinum) as a source of docosahexaenoic acid; or CON + 2.6% of a co-extruded mixture of full-fat flaxseed (FFF) as a source of α-linolenic acid. Day-old female offspring were assigned to diets (breeder-offspring): 1) CON-CON, 2) CON-DMA, 3) CON - FFF, 4) DMA - CON, 5) DMA - DMA, 6) FFF - CON or 7) FFF - FFF, followed by a standard layer diet through 18 weeks of age (WOA) to 42 WOA.3. Antibody titres against infectious bronchitis (IBV) and Newcastle disease (NDV) were measured at six days and six WOA, and plasma FA profile was measured at 18 and 42 WOA.4. Pullets from FFF-fed breeders had higher antibody titres against IBV and NDV than pullets fed DMA (P < 0.05). Feeding FFF to offspring increased plasma ∑n-3 FA at 18 and 42 WOA, whereas feeding DMA to offspring reduced ∑n-6 FA at 18 WOA.5. In conclusion, independent of breeder strain, alpha linoleic acid (ALA) and DHA sources showed varied responses. Feeding breeders FFF increased plasma concentration of antibody titres and n-3 FA whereas DMA reduced plasma concentration of ∑n-6 FA.

Growth performance, breast yield, gastrointestinal ecology and plasma biochemical profile in broiler chickens fed multiple doses of a blend of red, brown and green seaweeds.

1. A total of 864 d old (male) Ross × Ross 708 broiler chicks were allocated to 48 floor pens (12 pens/treatment and 18 birds/pen) to investigate dose-response of a blend of seaweeds (SB) on growth performance, breast yield, jejunal histomorphology, microbial metabolites and community and plasma biochemical profile. 2. A maize-soybean meal diet was formulated with 0, 5, 10 or 20 g/kg of SB. Diets were formulated for a three-phase feeding programme (starter: d 0-10, grower: d 11-24, and finisher: d 25-42) and met or exceeded Aviagen nutrient specifications. Diets were allocated to pens (n = 12) balanced for body weight (BW). Birds had free access to feed and water, BW and feed intake (FI) were monitored by phase. One bird per pen was randomly selected on d 42, bled for plasma, and samples for intestinal tissue and caecal digesta were taken. Microbial DNA was extracted and submitted for microbial community profile using the Illumina Miseq® platform. 3. In the starter phase, SB linearly (P ≤ 0.01) improved BW, body weight gain (BWG), and FCR. However, the improvement was quadratic, such that there was no further improvement beyond 5 g/kg SB inclusion. Growth performance response to SB in the grower phase was similar to the starter phase, with the exception of FCR (P > 0.05). Overall, from d 0-42, a linear and quadratic (P < 0.01) response was observed for final BW (d 42), whereby birds fed 5, 10 and 20 g/kg SB were heavier than control by 166, 183 and 180 g, respectively. A quadratic (P = 0.03) effect was observed for breast yield in response to SB. There was a quadratic reduction (P < 0.05) in gamma-glutamyl transferase (GGT) and a linear increase in glutamate dehydrogenase (GDH) in response to SB. Supplemental SB linearly reduced (P ≤ 0.04) the relative abundance of phylum Bacteroidetes and Proteobacteria, and increased the abundance of phylum Firmicutes (linearly; P = 0.02) and Actinobacteria (quadratically; P = 0.03). 4. The data indicated that the optimal inclusion for SB was between 5 and 10 g/kg for improved growth performance and breast yield. However, increased abundance of Firmicutes and actinobacteria in the caecal digesta suggested that the higher doses enhanced prebiotic effects of seaweed components.

Impact of combined ß-glucanase and xylanase enzymes on growth performance, nutrients utilization and gut microbiota in broiler chickens fed corn or wheat-based diets.

The effects of a xylanase and ß-glucanase (XB) blend (2,500 U of xylanase and 250 U of ß-glucanase per kg of complete feed) on growth performance, nutrients utilization and digesta microbiota in broiler chickens were investigated. A total of 140 day-old male Ross 308 broiler chicks were randomly assigned to 7 replicate cages and fed experimental diets. Diets were based on either corn or wheat without or with supplemental XB. Performance was monitored weekly and excreta were collected from d 17 to 20 for nutrients digestibility and AMEn measurements. On d 21, jejunal contents were collected for viscosity determination whereas ileal and cecal contents were obtained for microbial analysis by Illumina sequencing. Microbial data were analyzed using QIIME and PLS-DA whilst other data were analyzed using SAS. Birds fed wheat diets had higher (P < 0.001) BWG (3.4%) than birds fed corn-based diet whilst birds fed XB had better BWG (4%) and FCR (7%) than birds fed non-XB diets. Birds fed wheat diet had higher (P < 0.001) NDF (46.5%) and less (P = 0.01) CP (-5.4%) digestibility compared to birds fed corn-based diet. XB reduced (P < 0.001) jejunal digesta viscosity to a greater extent in wheat diet (-31%) than in corn-based diet (-10%). Birds fed wheat-based diet with XB had higher (3.5%) starch digestibility than birds fed this diet without XB. Janthinobacterium was associated with non-XB corn-based diet, whereas Ruminococcus, Lachnospiraceae, Lactobacillaceae, Peptostreptococcaceae, Clostridiales, Acidovorax and Blautia were associated with XB corn-based diet in the ileum. A relatively similar microbiome clustering was observed in wheat-based treatments in the cecum. There were no significant (P ≥ 0.05) correlations between selected ileal or cecal bacterial taxa and AMEn. Diet impacted growth performance but XB was efficacious across diet types, implying that degradation of dietary fibrous components by feed enzymes may stimulate performance in young birds. Data provided significant insight on ileal and cecal microbial profile associated with the dietary types and XB; however their functional roles require further investigations.

Efficacy of New 6-Phytase from Buttiauxella spp. on Growth Performance and Nutrient Retention in Broiler Chickens Fed Corn Soybean Meal-based Diets.

A total of 420 day-old male Ross chicks were weighed at d 1 of life and assigned to test diets to assess the efficacy of a new Buttiauxella spp. phytase expressed in Trichoderma reesei. Diets were: positive control (PC) adequate in nutrients and negative control (NC) diet (40% and 17% less available phosphorous (P) and calcium (Ca), respectively) supplemented with 6 levels of phytase 0, 250, 500, 750, 1,000, and 2,000 phytase units (FTU)/kg of diet. All diets had titanium dioxide as digestibility marker and each diet was allocated to ten cages (6 birds/cage). Diets were fed for 3 wk to measure growth performance, apparent retention (AR) on d 17 to 21 and bone ash and ileal digestibility (AID) on d 22. Growth performance and nutrient utilization was lower (p<0.05) for NC vs PC birds. Phytase response in NC birds was linear (p<0.05) with 2,000 FTU showing the greatest improvement on body weight gain (20%), feed conversion (7.4%), tibia ash (18%), AR of Ca (38%), AR of P (51%) and apparent metabolizable energy corrected for nitrogen (5.1%) relative to NC. Furthermore, phytase at ≥750 FTU resulted in AID of total AA commensurate to that of PC fed birds and at ≥1,000 FTU improved (p<0.05) AR of P, dry matter, and N beyond that of the lower doses of phytase and PC diet. In conclusion, the result from this study showed that in addition to increased P and Ca utilization, the new Buttiauxella phytase enhanced growth performance and utilization of other nutrients in broiler chickens in a dose-dependent manner.

Growth performance, nutrient utilization, and digesta characteristics in broiler chickens fed corn or wheat diets without or with supplemental xylanase.

Efficacy of supplemental xylanase on growth performance, nutrient utilization, and digesta characteristics in broiler chickens fed corn- or wheat-based diets was investigated. In experiment 1, 192 male broilers (8 birds/pen; n = 6) were fed 4 diets (corn or wheat without or with 1,250 xylanase units/kg) in 2 phases (starter, d 0-21 and grower, d 22-42). There was no interaction (P > 0.05) between diet and xylanase on performance (d 0-42). Wheat diets resulted (P < 0.01) in better performance than corn diets, whereas xylanase-fed birds had improved (P < 0.01) BW gain (2,457 vs. 2,275 g) and feed per gain (1.677 vs. 1.762) relative to birds not fed xylanase. In experiment 2, TiO2 (0.3%) was added in starter diets used in experiment 1, allocated to 13-d-old broiler chicks (n = 6) housed in cages (6 birds/cage) and fed up to d 21. Excreta samples were obtained from d 17 to 20 and birds were euthanized on d 21 for digesta. Corn diets had a greater concentration (10.7 vs. 9.8%) of insoluble nonstarch polysaccharides (NSP) than wheat diets, which in turn had more than twice the concentration of soluble NSP. There was an interaction (P < 0.03) between diet type and xylanase on jejunal digesta viscosity but not (P > 0.10) on apparent ileal digestibilities of nutrients, cecal volatile fatty acids, and AMEn. In this context, diet type influenced (P < 0.05) cecal volatile fatty acids and retention of nutrients and fiber but did not affect (P = 0.45) AMEn. In contrast, xylanase-fed birds showed higher (P < 0.05) ceca digesta acetic acid, apparent ileal digestibilities of nutrients, and retention of components. As a result, birds fed xylanase had higher AMEn (3,059 vs. 2,995 kcal/kg; P < 0.01) compared with birds not fed xylanase. Although wheat diets had superior growth performance, the AMEn was similar in both diets. Xylanase improved growth performance and AMEn independent of diet type, suggesting hydrolysis of both soluble and insoluble NSP.

Effect of supplementing direct-fed microbials on broiler performance, nutrient digestibilities, and immune responses.

Direct-fed microbials (DFM) are used to improve livestock health and performance. The effects of 2 DFM products, a blend of 3 Bacillus strains (DFMB) and a Propionibacteriumspp. (DFMP), on broiler performance, nutrient utilization, and immune responses were investigated. Day-old (n = 120) male broilers were divided into 24 groups of 5 birds and fed 3 wheat-based diets in mash form (8 groups per diet) from d 1 to 22. The control diet was fed without or with 7.5 × 10(4) cfu/g of either DFMB or DFMP. From d 19 to 21 fecal samples were collected for determination of total tract apparent retention (TTAR) of nutrients and AMEn. On d 21, feed intake and BW were determined. On d 22, 5 birds per treatment were killed by cervical dislocation to collect jejunal and ileal contents for determination of digesta viscosity and apparent ileal digestibility (AID) of nutrients, respectively, and ileum, cecal tonsil, and spleen tissues for Toll-like receptors (TLR) and cytokine expressions. Compared with the control, DFM did not affect BW gain and feed intake but DFMP reduced G:F (P < 0.01). Compared with the control (2,875 kcal/kg), birds fed on DFMB and DFMP had higher AMEn (2,979 and 2,916 kcal/kg, respectively; P < 0.05), whereas both DFM reduced the AID of DM (P < 0.001) and CP (P < 0.01). Furthermore, DFMP reduced TTAR of NDF (29.0 vs. 18.4%; P < 0.001), whereas both DFM increased TTAR of DM and fat (P < 0.001). Supplementing DFMP downregulated ileal expression of TLR-2b, IL-2, IL-4, IL-6, IL-10, and IL-13, whereas DFMB downregulated TLR-2b, IL-2, IL-4, and IL-6 in all 3 tissues, IL-10 in the spleen, and upregulated IL-13 in the spleen. In conclusion, the DFM did not improve performance but increased the AMEn of diet by possibly increasing DM and fat retention. Overall, both DFM showed an antiinflammatory effect in the ileum, but DFMB had more effects on local and systemic immunity than DFMP.

Growth and physiological responses of growing pigs to wheat-corn distillers dried grains with solubles.

Gaining a detailed knowledge on the impact of a feedstuff on pig growth and physiological responses is critical for its effective utilization. Thus, the purpose of this study was to investigate the effect of distillers dried grains with solubles derived from co-fermentation of wheat and corn (wcDDGS) on performance, carcass and visceral organ weights, whole-body O2 consumption and heat production (HP) in growing barrows. The experimental diets were as follows: corn-soybean meal diet (Control), Control + 15% wcDDGS and Control + 30% wcDDGS. In Exp. 1, 48 pair-housed pigs of average BW 18.6 ± 1.5 kg (mean ± SD) were allotted to the 3 diets (n = 8). Pigs had free access to water and feed for a 28-day period during which ADG and ADFI were calculated weekly. Thereafter, 1 pig/pen was killed to measure carcass and visceral organ weights. Overall, wcDDGS linearly decreased (p < 0.05) ADFI and ADG but had no effect on G:F (p > 0.10). The ADFI was 1.55, 1.45 and 1.36 kg/day for diets containing 0, 15 and 30% wcDDGS respectively; corresponding values for ADG were 0.79, 0.75 and 0.67 kg/day respectively. A linear decline (p = 0.01) in eviscerated hot carcass weight was observed as dietary wcDDGS increased. In Exp. 2, 18 pigs of average BW 20.4 ± 2.4 kg (mean ± SD) were individually housed in metabolism crates and fed the 3 diets (n = 6) at 550 kcal ME kg BW(-0.60) day for a 16-day period followed by measurement of O2 consumption using an indirect calorimeter. Diet had no effect (p > 0.10) on whole-body O2 consumption and HP. In conclusion, increasing wcDDGS content in growing pig diets linearly reduced ADFI, ADG and eviscerated hot carcass weight but had no effect on G:F, visceral organ weights or HP.

Growth performance, organ weights, and blood parameters of broilers fed diets containing expeller-extracted canola meal.

A study was conducted to determine the effect of including expeller-extracted canola meal (EECM) in diets for broilers on performance, thyroid gland size, liver and kidney sizes, blood serum concentration of triiodothyronine and tetraiodothyronine, hemoglobin content in blood, hematocrit, and histology of liver and kidney. A total of 200 male broiler chicks (1 d old) were divided into 40 groups of 5 birds balanced for BW and fed 5 diets in a completely randomized design (8 groups/diet) from d 1 to 21 of age. The diets were a complete corn-soybean meal-based basal diet with 0, 10, 20, 30, or 40% of EECM. Diets were formulated to have the same ME, CP, Ca, nonphytate P, and standardized ileal digestible Met and Lys contents. The EECM contained (% of DM) 37.8% CP, 0.74% Met, 2.14% Lys, 1.62% Thr, 1.61% Val, and 7.64 µmol/g of glucosinolates. An increase in dietary level of EECM from 0 to 40% resulted in a linear decrease in feed intake (P < 0.001) by 4.8 g/21-d period for each 1% increase in EECM and in BW gain (P < 0.001) by 6.0 g/21-d period for each 1% increase in EECM. However, dietary EECM linearly increased liver weight relative to live BW (P < 0.001) and serum tetraiodothyronine concentration (P = 0.019). An increase in dietary level of EECM from 0 to 40% did not result in a significant increase in kidney weight relative to live BW. There was no effect of EECM on heart and thyroid gland weights relative to live BW or on the blood hemoglobin content, hematocrit, and serum triiodothyronine concentration. In conclusion, an increase in dietary level of EECM resulted in reduced growth performance and may interfere with liver function, likely because of increased dietary concentration of glucosinolates. Thus, the amount of EECM included in broiler diets should be based on the desired growth performance and the cost of the EECM.

Effect of Escherichia coli lipopolysaccharide challenge on eggshell, tibia, and keel bone attributes in ISA brown hens exposed to dietary n-3 fatty acids prior to onset of lay.

The impact of Escherichia coli lipopolysaccharide (LPS) challenge on eggshell, tibia, and keel bone characteristics in ISA brown hens derived from breeders and pullets fed omega-3 polyunsaturated fatty acids (n-3 PUFA) was examined. The breeders were fed the following diets: 1) Control (CON); 2) CON + 1% microalgae as the source of docosahexaenoic acid (DHA); and 3) CON + 2.6% of a co-extruded mixture of full-fat flaxseed and pulses as a source of α-linolenic acid (ALA). During the pullet phase, offspring from breeders fed CON were fed CON or supplemented diets, and offspring from supplemented diets either continued with respective n-3 PUFA diets or CON. At 18 weeks of age (WOA), pullets were fed a common layer diet to 42 WOA. A total of 5 birds were selected based on the average body weight (BW) of each treatment and moved to an individual cage at 41 WOA. Three days before the end of 42 WOA, all the birds were weighed and subcutaneously injected with either saline or 4 mg LPS/kg BW. Eggs were recorded, labeled, and kept for egg quality analyses. At 42 WOA, birds were necropsied for tibia and keel bone samples. Administration of LPS reduced eggshell breaking strength, eggshell weight, tibia, and keel bone ash content (P < 0.05). Specifically, LPS challenged hens had 14.9, 11.1, 9.2, and 11.6% lower eggshell breaking strength, eggshell weight, keel, and tibia ash content, respectively relative to unchallenged hens. Hens from breeders and pullets fed n-3 PUFA had similar (P > 0.05) eggshell, tibia, and keel bone attributes to control hens. In conclusion, the provision of ALA and DHA to breeders and their offspring did not alleviate the negative effects of LPS on eggshell, tibia, and keel bone characteristics in laying hens.

Impact of fiber on growth, plasma, gastrointestinal and excreta attributes in broiler chickens and turkey poults fed corn- or wheat-based diets with or without multienzyme supplement.

Effects of fiber on growth performance, gizzard attributes, ileal digesta viscosity, plasma uric acid (PUA) and excreta characteristics were investigated in broiler chickens (experiment 1) and turkey poults (experiment 2) fed corn or wheat-based diets with or without multienzyme supplement (MES). Fibrous diets were created by adding 10% corn distillers dried grains with solubles or wheat middlings in corn or wheat-based diets, respectively. The MES had main activities of xylanase and ß-glucanase. A total of 960-d old Ross x Ross 708 male chicks and 720-d old male Hybrid toms were allocated to eight grain, fiber and MES combinations to give 6 replicates per combination. In each experiment, birds had free access to feed and water for 28 days. Excreta samples were collected for 3-d prior to the end and on d 28, body weight and feed intake were recorded, birds bled and subsequently necropsied for gastrointestinal samples. There was an interaction (P ≤ 0.036) between grain, fiber and MES in broilers final body weight (FBW) and BW gain (BWG). In this context, high fiber corn diets reduced FBW and BWG and supplementation of MES improved these parameters. Broilers fed corn had a higher (P < 0.05) FBW (1,462 vs. 1,424 g) and BWG (1,416 vs. 1,378 g) than birds fed wheat diets. Broilers fed corn-based diets without fiber diets had a higher ileal viscosity and excreta moisture compared to birds fed wheat-based and high fiber diets. Broilers fed low fiber wheat diets without MES had higher (P < 0.05) PUA concentration compared to birds fed low fiber corn diets without MES. Poults fed wheat diets had a higher (P < 0.05) FBW (1,441 vs. 1,408 g) and BWG (1,376 vs. 1,343 g) than poults fed corn diet. The MES supplementation in corn-based diets rich in fiber increased (P = 0.03) gizzard weight in poults. In conclusion, there were varied growth and physiological responses in broilers and turkey suggesting the need for refining enzyme application for different poultry species.

Metabolizable energy and standardized ileal digestible amino acid contents of expeller-extracted canola meal fed to broiler chicks.

An experiment was conducted to determine the standardized ileal digestible amino acid (AA) and AMEn contents of expeller-extracted canola meal (EECM) fed to broiler chicks. One hundred forty-four broiler chicks were divided into 24 groups of 6 birds balanced for BW and fed 4 diets in a completely randomized design (6 groups per diet) from d 14 to 21 of age. The diets were a corn-soybean meal-based basal diet formulated to meet NRC nutrient requirements, the basal diet with energy- and AA-yielding ingredients replaced by 30% of either solvent-extracted canola meal (SECM) or EECM, and a low-protein casein-cornstarch-based diet. The SECM, which is commonly used in formulating poultry diets, was fed for comparison with EECM, whereas the casein-cornstarch-based diet was fed to estimate basal endogenous AA losses for determining standardized ileal digestibility of AA. All 4 diets contained titanium oxide (0.3%) as an indigestible marker, and nutrient digestibility and retention were determined by the substitution method. From d 19 to 21, excreta samples were collected for AMEn determination. On d 21, the birds were killed by cervical dislocation, and contents of the whole ileum were obtained for determination of AA digestibility. Expeller-extracted canola meal had greater (P<0.05) standardized ileal digestible contents of Gly, Leu, Ser, Thr, Asp, and Glu and tended to have greater (P<0.10) standardized ileal digestible contents of Ile, Lys, Phe, Ala, and Tyr than SECM. Compared with SECM, EECM had greater (P<0.001) AMEn (2,694 vs. 1,801 kcal/kg). The results show that the EECM evaluated in the current study had greater standardized ileal digestible AA and AMEn contents than SECM, and hence, it may be a better source of protein and energy for broiler chicks than SECM. The standardized ileal digestible AA and AMEn values of EECM used in the current study could be used when formulating broiler chicken diets using the same to minimize the N excretion and feeding cost.

Standardized ileal amino acid digestibility in dry-extruded expelled soybean meal, extruded canola seed-pea, feather meal, and poultry by-product meal for broiler chickens.

Ileal digestibility of amino acids (AA) in dry-extruded expelled soybean meal (DESBM), co-extruded canola seed-pea blend (ECSP, 50:50 wt/wt basis), poultry by-product meal (PBPM), and feather meal (FM) were determined in broiler chicks. For each ingredient, 5 samples each collected on different occasions were evaluated. Birds (n = 180 for each sample) were fed a commercial starter diet from d 1 to 15 of age followed by the test diets from d 15 to 21. Dry-extruded expelled soybean meal, ECSP, PBPM, and FM were included in the test diets at 95.3, 95.3, 38.4, and 28.4%, respectively, as the sole source of AA and balanced for minerals and vitamins. Chromic oxide (0.3%) was included in all diets as a digestibility marker. Each diet (5 per ingredient) was randomly assigned to 6 replicate cages, each with 6 birds. On d 21, birds were killed to collect ileal digesta for determining the apparent ileal AA digestibility on cage basis. The standardized ileal digestibility (SID) values were calculated using ileal endogenous AA losses previously determined in our laboratory. The apparent ileal digestibility of AA ranged from 78 to 91%, 68 to 83%, 51 to 81%, and 39 to 74% for DESBM, ECSP, PBPM, and FM, respectively. The respective ranges for SID values were 83 to 96%, 72 to 85%, 58 to 86%, and 42 to 78%. Among the indispensable AA, the lowest SID was observed for Thr in all test ingredients, whereas the highest SID was observed for Phe except in ECSP in which Arg had the highest SID. The SID of Lys (CV) were 91% (2.8%), 79% (2.0%), 78% (7.4%), and 60% (10%) for DESBM, ECSP, PBPM, and FM, respectively, whereas the SID of TSAA (CV) were 88% (4.5%), 77% (2.4%), 74% (9.0%), and 55% (18%), respectively. These SID AA data will help nutritionists to formulate broiler diets that more closely match the birds' requirements and minimize nutrient excess.

The effect of alternative feeding strategies on the feeding motivation of broiler breeder pullets.

Due to genetic selection for fast growth and high breast meat yield, commercial strains of broiler chickens and broiler breeders are predisposed to high feed intake; however, feeding broiler breeders ad libitum impairs their health and reproductive performance. Broiler breeders are feed-restricted throughout rearing to maintain health and performance, yet feed restriction results in hunger, feeding frustration and lack of satiety. The objective of this study was to examine the effect of alternative feeding strategies, including feed additives (separately or combined) and a fixed non-daily feeding schedule, on the feeding motivation and welfare of broiler breeders during rearing. At 3 weeks of age, 180 Ross 308 breeder pullets were allocated to 90 cages and fed with one of five isocaloric treatments: (1) daily control diet (control), (2) daily calcium propionate diet (CaP), (3) daily soybean hull diet (SBH), (4) daily alternative diet (alternative: CaP + SBH) and (5) 4/3 control diet (four on-feed days and three non-consecutive off-feed days per week). The CaP diet included calcium propionate at 1.4% from 3 to 6 weeks of age, and at 3.2% from 7 to 12 weeks of age, and the SBH diet contained soybean hulls included at 40%. The alternative diet included both soybean hulls and calcium propionate at the same inclusion rate as the SBH and CaP diets, respectively. Pullets were weighed and scored for feather coverage every week. A feed intake test was conducted at 3, 4, 8, 10 and 11 weeks of age for 10 min during on- and off-feed days. At 12 weeks of age, feather samples were analysed for fault bars. Data were analysed using linear mixed regression models, with cage nested in the models and age as a repeated measure. At 4 weeks of age, pullets fed soybean hull-enriched diets (SBH and alternative diets) and those on the 4/3 schedule had lower feed intake than control pullets (P = 0.02). Feathers from pullets fed the SBH diet had fewer fault bars than those fed the CaP diet (P = 0.04). The results indicated that the inclusion of soybean hulls (alone or combined with calcium propionate) and a 4/3 feeding schedule can reduce feeding motivation of broiler breeders during early rearing.

n-3 fatty acids fed to ISA brown and Shaver white breeders and their female progeny during rearing: Impact on egg production, eggshell, and select bone attributes from 18 to 42 weeks of age.

The impact of feeding sources of n-3 fatty acids (FA) to ISA brown and Shaver white breeders and their female offspring during rearing on egg production, eggshell, tibia, and keel bone attributes was examined. Breeders were fed Control (CON) or CON + 1% dried microalgae (DMA: Aurantiochytrium limacinum) as the source of docosahexaenoic acid or CON + 2.6% of a coextruded mixture of full-fat flaxseed (FFF) and pulses as a source of α-linolenic acid. Day-old offspring were fed 1) breeder CON-pullet CON (CON-CON), 2) breeder CON-pullet DMA (CON-DMA), 3) breeder CON-pullet FFF (CON-FFF), 4) breeder DMA-pullet CON (DMA-CON), 5) breeder DMA-pullet DMA (DMA-DMA), 6) breeder FFF-pullet CON (FFF-CON), and 7) breeder FFF-pullet FFF (FFF-FFF). At 18 wk of age (WOA), pullets were fed a common layer diet to 42 WOA for egg production and bone quality assessments. There was no (P > 0.05) interaction between strains and diets and the main effect of diets on egg production, egg mass, and eggshell quality. There was an interaction (P = 0.008) between strain and diet on egg weight (EW); however, the strain effect on EW (P < 0.001) was such that ISA brown had heavier eggs than Shaver white. Shaver white had higher (P < 0.001) eggshell %, eggshell, and tibia breaking strength (BS), as well as tibia ash concentration compared with ISA brown hens. In contrast, ISA brown hens exhibited heavier (P < 0.05) tibia and keel bones. Feeding breeders DMA and pullets both sources of n-3 FA increased tibia medullary ash concentration compared with other diets (P < 0.001). Shaver white hens showed greater decline in tibia BS (83.7 vs. 96.3%) and ash content (84.1 vs. 94.3%) than ISA brown hens from 18 to 42 WOA (P < 0.05). Strain and diets exhibited independent effects on eggshell, tibia, and keel attributes. Provision of α-linolenic acid and docosahexaenoic acid to breeders and offspring improved tibia medullary ash concentration at 42 WOA.

Impact of feeding microalgae (Aurantiochytrium limacinum) and co-extruded mixture of full-fat flaxseed as sources of n-3 fatty acids to ISA brown and Shaver white breeders and progeny on pullet skeletal attributes at hatch through to 18 weeks of age.

Impact of feeding n-3 fatty acids (FA) to ISA brown and Shaver white breeders and their progeny on bone development in pullets was investigated. Breeders were fed Control (CON); CON + 1% microalgae (DMA: Aurantiochytrium limacinum) as the source of docosahexaenoic acid; and CON + 2.6% of a co-extruded mixture of full-fat flaxseed (FFF) and pulses mixture as source of α-linolenic acid. Test diets (DMA and FFF) were balanced for total n-3 FA and n-6: n-3 FA ratio. Samples of day-old progeny were euthanized for bone mineral content (BMC) and tibia collagen type II. The remaining pullets were fed posthatch treatments as follows: from breeder CON: CON (CON-CON), DMA (CON-DMA), and FFF (CON-FFF), from breeder DMA: CON (DMA-CON) and DMA (DMA-DMA) and from breeder FFF: CON (FFF-CON) and FFF (FFF-FFF). A total of 60 pullets per posthatch diets were reared in cages (12 pullets/cage, n = 5) with free access to feed and water, bled at 6, 12, and 18 wk of age (WOA) for bone turnover markers and necropsied at 18 WOA for tibia and femur samples. Day-old pullets from breeder fed CON had greater BMC (P < 0.001) relative to those from breeders fed other diets. There was strain and diet interaction (P ≤ 0.024) on tibia breaking strength (TBS) and tibia cortical ash concentration at 18 WOA such that diet responses were only observed in Shaver white pullets. In this context, TBS of DMA-DMA and FFF-FFF was greater than for pullets originating from CON breeder, and the cortical ash weight of DMA-DMA and FFF-FFF pullets was 23.8 and 20.2%, respectively, higher than for CON-CON pullets. In conclusions, the strain effects were strong on tibia attributes on 18-week-old pullets. Breeder feeding of n-3 FA was more effective when concomitant with posthatch feeding of n-3 FA in supporting the skeletal strength and cortical bone development in Shaver white pullets. Further investigations are warranted to establish the impact these strategies on skeletal health during laying cycle.

Nucleotide-rich yeast extract fed to broiler chickens challenged with Eimeria: impact on growth performance, jejunal histomorphology, immune system, and apparent retention of dietary components and caloric efficiency1.

Nucleotide-rich yeast extract (YN) was investigated for its effects on growth performance, jejunal histomorphology and mucosal immunoglobulin A (IgA), immune organs weight and apparent retention (AR) of components in broiler chickens challenged with Eimeria. A total of 336 day-old male chicks (Ross x Ross 708) were placed in floor pens and provided a corn-soybean meal-based diet without or with YN (500 g/mt) (n = 14). On day 10, 7 replicates per diet were orally administered with 1 mL of sporulated E. acervulina and E. maxima oocysts and the rest (non-challenged control) administered equivalent distilled water creating a 2 × 2 factorial arrangement for the post-challenge period (day 11 to 35). Feed intake (FI), BWG, and FCR responses were measured in pre- and post-challenge periods. Excreta samples were collected on day 14 to 17 and 31 to 34 for oocyst count and AR of components, respectively. On day 15 and 35, 5 birds/pen were necropsied for intestinal samples. Spleen, bursa, and thymus weights were also recorded at both time points and breast yield on day 35. Diet had no effect (P > 0.05) on pre-challenge growth performance. Interaction (P = 0.046) between Eimeria and YN on FI was such that Eimeria challenge increased FI (day 11 to 35) in non-YN birds. There was no interaction (P > 0.05) between Eimeria and YN on other post-challenge responses. Eimeria reduced (P < 0.05) BWG, FCR, caloric efficiency, day 15 jejunal villi height and IgA concentration, and increased (P < 0.01) day 15 spleen weight. On day 35, YN increased bursa weight (1.57 vs. 1.78 mg/g BW, P = 0.04). There was a tendency for an interaction effect (P = 0.09) on day 35 thymus weight, such that in challenged birds, YN fed birds tended to have a lighter thymus relative to non-YN fed birds. In conclusions, independent of Eimeria challenge, supplemental YN had no effect on growth performance, caloric efficiency, and intestinal function but increased immune organ weights.

The effect of alternative feeding strategies for broiler breeder pullets: 2. Welfare and performance during lay.

Feeding broiler breeders to satiety has negative consequences on their health and reproduction. Alternative feeding strategies during rearing can improve welfare, although their implications during lay are not well understood. The objective was to examine the effect of rearing feeding treatments on the reproductive performance and feeding behavior of broiler breeders under simulated commercial conditions. At 3 wk of age, 1,680 Ross 308 pullets were allocated to 24 pens under 1 of 4 isocaloric treatments: 1) daily control diet; 2) daily alternative diet (40% soybean hulls and 1 to 5% calcium propionate); 3) 4/3 control diet (4 on-feed days, 3 non-consecutive off-feed days per week); and 4) graduated control diet. Feeding frequency of the graduated treatment varied with age and finished on a daily basis. At 23 wk of age, group sizes were adjusted to 40 hens, and 5 mature Yield Plus Males roosters were introduced to each pen. Pens were under the same daily feeding management and same diet during lay. The performance of broiler breeders (growth rate, body weight uniformity, and reproductive performance) was determined until 64 wk of age. At the end of lay, feeding motivation was examined with a feed intake test and a compensatory feeding test. Data were analyzed using linear mixed regression models, with pen nested in the models and age as a repeated measure. The laying rate of hens reared on the graduated treatment decreased slower compared to control hens, resulting in a higher cumulative egg production (178.2 ± 3.8 eggs/hen) than control hens (165.2 ± 3.8 eggs/hen, P < 0.01) by 64 wk of age. Hens reared on non-daily feeding treatments laid lighter eggs with relatively heavier yolks and had higher feed intake at the end of lay than hens fed daily during rearing (P = 0.02). In conclusion, rearing feeding treatments impacted the growth rate and body weight uniformity during lay, feeding motivation at the end of lay, and the laying rate and hatchability depending on hens' age.

Growth performance, apparent retention of components, and excreta dry matter content in Shaver White pullets (5 to 16 week of age) in response to dietary supplementation of graded levels of a single strain Bacillus subtilis probiotic.

Administered in adequate amounts, probiotics can be an alternative to antibiotic growth promoters in poultry production. This study evaluated dose response of a single strain of Bacillus subtilis (SSB, DSM29784) on growth performance, apparent retention (AR) of components, and excreta DM content in pullets. A basal corn-soybean meal diet was formulated to meet the specifications for grower (week 5 to 10) and developer (week 11 to 16) phases. In each phase, SSB was added to the basal diet to create 4 test diets: 0 (control, CON), 1.1E+08 (low; LSSB), 2.2E+08 (medium; MSSB), or 1.1E+09 (high; HSSB) CFU of SSB/kg of feed. All diets had TiO2 (0.5%) as a digestibility marker. A total of 720 day-old Shaver White chicks were placed in 48 cages (15 pullets per cage) and reared on a commercial antibiotic free diet for a 4-wk period. At the beginning of week 5, treatments were allocated based on cage BW (n = 12). Birds had free access to feed and water throughout. The BW, BW uniformity, feed intake (FI) and FCR were obtained weekly. Excreta was collected at the end of each phase for AR of DM, organic matter, CP, neutral detergent fiber, minerals, and AME, as well as excreta DM content. In response to SSB inclusion, BW improved in a linear (P < 0.005) and quadratic (P < 0.0001) manner in grower. FI decreased in a linear and quadratic pattern (P < 0.05, week 8 to 10) in grower, and linearly (P < 0.05) across the developer phase. Overall FCR improved in linear and quadratic pattern (P < 0.01) in the grower phase. In both the phases, AME improved in a quadratic pattern (P < 0.05). Inclusion of SSB had a linear reduction (P < 0.0001) in excreta moisture content in the grower phase. In summary, these results demonstrate that B. subtilis probiotic improved performance through enhanced nutrient utilization and reduced excreta moisture content indicating improved pullet gut health.

Effects of rearing and adult laying housing systems on medullary, pneumatic and radius bone attributes in 73-wk old Lohmann LSL lite hens1.

We determine interactive effect of a combined model of housing systems for rearing pullets and raising adult birds on bone quality. The LSL-Lite pullets were reared in either an aviary system (A) or conventional cages (C). At week 16, the birds were transferred either to the same housing type through the adult stage (A-A or C-C, for rearing and adult phase, respectively) or to enriched system (A-E or C-E, respectively). In the rearing stage, C cages housed 16 pullets/cage (week 0 to 6) and 8 pullets/cage (week 6 to 16) with a space allowance of 145 and 290 cm2/pullet, respectively; the rearing aviary housed 756 pullets/enclosure allowing 285 cm2/pullet (week 0 to 6) and 754 cm2/pullet (week 6 to 16). In the adult phase, C cages were 58.4 cm wide × 66.0 cm deep (482 cm2/pullet, 8 pullets/cage). For adult A, a commercial multi-tier aviary provided a space allowance >1000 cm2/hen system with litter area. Enriched system housed 60 birds/cage at 750 cm2/bird with perches, nest, and scratch mat. Bone samples were collected from the adult phase (week 73) and analysed for bone quality indices including bone breaking strength (BBS), total bone weight (TBW), ash content of the medullary (femur and tibia), pneumatic (humerus and keel), and radius bones. The A-A hens had the greatest (P < 0.05) TBW for medullary (femur and tibia) and pneumatic (humerus and keel) bones compared with hens from other housing models with exception of C-E hens. In addition, ash content was heavier (P = 0.048) for both A-A and C-E managed birds compared to the other housing. Birds in C-C system had the least score (P < 0.05) for TBW and ash content in all bone types. Regardless of the housing system, BBS was correlated (r = 0.60; P < 0.01) with the amount of ash and TBW, particularly for humerus and tibia. The results provide an insight on the impact of type of housing system in rearing and production stages on late cycle bone quality.

Interactive effects of calcium and top-dressed 25-hydroxy vitamin D3 on egg production, egg shell quality, and bones attributes in aged Lohmann LSL-lite layers1.

Calcium and vitamin D are critical in attenuating metabolic Ca insufficiency often observed in older hens. We investigated interactive effects of dietary Ca and top-dressed 25-hydroxy vitamin D3 (25OHD3) on egg production, eggshell quality (thickness, EST, and breaking strength, ESBS), serum Ca, kidney, liver, and bones attributes in 74-wk old Lohmann LSL-lite layers. A total of 4 levels of Ca (3.0, 3.5, 4.0, and 4.5%) and 3 levels of 25OHD3 (0, 69, and 138 µg/kg) were tested. All diets had basal level of 3,300 IU of vitamin D3/kg, were allocated to 84 individually housed hens (n = 7), and fed to 81 wk of age. Dual-energy X-ray absorptiometry was used to measure bone mineral content (BMC) and density (BMD) in left ulna, femur, and tibia at week 74 (13 spare birds, baseline) and week 81. Birds fed diets containing 3.0, 3.5, 4.0, and 4.5% Ca consumed 3.4, 4.1, 4.2, and 4.8 Ca g/b/d. Interaction (P < 0.05) between Ca and 25OHD3 was such that 25OHD3 linearly increased egg weight and percentage of eggs graded as jumbo (≥70 g) at 3.0, 3.5, and 4.5% Ca levels. There was no interaction (P > 0.05) between Ca and 25OHD3 on the rest of the parameters. Calcium increased EST and ESBS quadratically (P < 0.05), EST increased with Ca intake up to 4.1 g of Ca/b/d whereas Ca intakes (3.4 and 4.8 g of Ca/b/d) had poor ESBS relative to intermediate Ca intakes. Kidney ash concentration increased linearly (P = 009) with Ca intake. However, BMC and BMD in ulna, tibia, and femur declined (P < 0.05) at week 81 relative to baseline. In conclusion, top dressed 25OHD3 linearly increased egg weight at various Ca intakes with no negative effect on eggshell quality or bone attributes. Feeding 4.1 to 4.2 g of Ca/b/d improved eggshell quality, however, higher intake deteriorated eggshell quality and increased renal ash accumulation with no benefit on skeletal integrity.