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.

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.

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.

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.

The effects of feeding yeast bioactives to broiler breeders and/or their offspring on growth performance, gut development, and immune function in broiler chickens challenged with Eimeria.

Yeast bioactives (YB) may stimulate broiler breeders (BB) to increase deposition of immunoglobulins (Ig) in eggs. We investigated the effects of feeding YB (mixture of derivatives from whole yeast subjected to enzymatic hydrolysis) to BB and/or their offspring on growth performance, gut development, and immune function in broiler chickens challenged with Eimeria. The BB (Ross 708 ♀ and Ross ♂) were assigned to 2 groups (60 ♀ and 10 ♂) and fed basal or basal diet supplemented with 500 g of YB/Mt. A total of 250 fertile eggs per treatment were collected, incubated, hatched, and sexed. Additional egg samples were analyzed for IgA and IgY contents. A total of 160 broiler chicks (80 ♀ and 80 ♂) from each breeder experimental group were placed in cages based on sex and BW resulting in 32 cages for each BB treatment group. Cages (16 per BB treatment group) were allocated to basal broiler chick diet or basal diet supplemented with 500 g of YB/Mt. On day 9, half of each BB by broiler chick dietary treatments was challenged with 1 mL of Eimeria culture (100,000 oocysts of Eimeria acervulina and 25,000 oocysts of Eimeria maxima). On day 14, all birds were necropsied for intestinal lesion scores and samples. Feeding YB to BB increased (P < 0.05) IgA concentration in egg yolk. Eimeria challenge decreased (P < 0.05) pancreas weight, jejunal villus height (VH), and growth performance but increased spleen weight, intestinal mass and jejunal mucosa IgA concentration. Independent of Eimeria challenge, feeding YB to BB and/or to chicks resulted in higher (P < 0.001) jejunal VH compared with feeding it to BB only or not at all. In conclusion, Eimeria challenge reduced growth performance and had negative effects on indices of intestinal function and health. Feeding YB to BB increased deposition of IgA in hatching eggs and improved jejunal VH independent of Eimeria challenge when fed to BB and/or to broiler chicks.